Commit Graph

2196 Commits

Author SHA1 Message Date
Maciej W. Rozycki f6a31da501 MIPS: BREAK instruction interpretation corrections
Add the missing microMIPS BREAK16 instruction code interpretation and
reshape code removing instruction fetching duplication and the separate
call to `do_trap_or_bp' in the MIPS16 path.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9696/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-08 01:09:55 +02:00
Maciej W. Rozycki 68893e0051 MIPS: Correct MIPS16 BREAK code interpretation
Correct the interpretation of the immediate MIPS16 BREAK instruction
code embedded in the instruction word across bits 10:5 rather than 11:6
as current code implies, fixing the interpretation of integer overflow
and divide by zero traps.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9695/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-08 01:09:53 +02:00
Maciej W. Rozycki 1f6d2c29b0 MIPS: Use `FPU_CSR_ALL_X' in `__build_clear_fpe'
Replace a hardcoded numeric bitmask for FCSR cause bits with
`FPU_CSR_ALL_X' in `__build_clear_fpe'.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9684/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-08 01:09:20 +02:00
Maciej W. Rozycki 27e28e8ec4 MIPS: Normalise code flow in the CpU exception handler
Changes applied to `do_cpu' over time reduced the use of the SIGILL
issued with `force_sig' at the end to a single CU3 case only in the
switch statement there.  Move that `force_sig' call over to right where
required then and toss out the pile of gotos now not needed to skip over
the call, replacing them with regular breaks out of the switch.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9683/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-08 01:09:18 +02:00
Maciej W. Rozycki 4a7c237182 MIPS: Reindent R6 RI exception emulation
Fold a nested `if' statement for the R6 case in `do_ri' into its
containing `if' block, removing excessive indentation causing code to
extend beyond 79 columns.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9679/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-08 01:09:06 +02:00
Maciej W. Rozycki a49dc4276e MIPS: ELF: Drop `get_fp_abi'
Commit 46490b57 [MIPS: kernel: elf: Improve the overall ABI and FPU mode
checks] reduced `get_fp_abi' to an elaborate pass-through.  Drop it
then.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9677/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-08 01:09:01 +02:00
Maciej W. Rozycki 241e9c465f MIPS: Correct the comment for and reformat `movf_func'
Correct a copy-and-paste issue with the description for `movf_func'
referring to `movt_func'.  Reformat the former function to match the
latter.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9675/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-08 01:08:54 +02:00
Maciej W. Rozycki f6c70ff4de MIPS: Clarify the comment for `__cpu_has_fpu'
Reword the comment for `__cpu_has_fpu' to make it unambiguous this code
is for external floating-point units only, generally MIPS I processors
using the original CP1 hardware interface.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9673/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-08 01:08:49 +02:00
Maciej W. Rozycki 1f44377900 MIPS: Correct the comment for FPU emulator traps
Adjust the explanatory comment for FPU emulator traps according to
ba3049ed [MIPS: Switch FPU emulator trap to BREAK instruction.];
originally coming from `do_ade'.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9672/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-08 01:08:47 +02:00
Huacai Chen f14ceff755 MIPS: perf: Add hardware perf events support for Loongson-3
This patch enable hardware performance counter support for Loongson-3's
perf events.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/9618/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:22:17 +02:00
Joshua Kinard 3057739138 MIPS: Add R16000 detection
This allows the kernel to correctly detect an R16000 MIPS CPU on systems that
have those.  Otherwise, such systems will detect the CPU as an R14000, due to
similarities in the CPU PRId value.

Signed-off-by: Joshua Kinard <kumba@gentoo.org>
Cc: Linux MIPS List <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/9092/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:22:13 +02:00
Andrew Bresticker f45e388ff0 MIPS: Provide fallback reboot/poweroff/halt implementations
If a machine-specific hook is not implemented for restart, poweroff,
or halt, fall back to halting secondary CPUs, disabling interrupts,
and spinning.  In the case of restart, attempt to restart the system
via do_kernel_restart() (which will call any registered restart
handlers) before halting.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9600/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:21:58 +02:00
Andrew Bresticker ea925a72a2 MIPS: smp: Make stop_this_cpu() actually stop the CPU
Since cpu_wait() enables interrupts upon return, CPUs which have
entered stop_this_cpu() may still end up handling interrupts.
This can lead to the softlockup detector firing on a panic or
restart/poweroff/halt.  Just disable interrupts and spin to ensure
nothing else runs on the CPU once it has entered stop_this_cpu().

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9601/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:21:58 +02:00
Toma Tabacu e6baf0e0b6 MIPS: LLVMLinux: Fix a 'cast to type not present in union' error.
Remove a cast to the 'mips16e_instruction' union inside an if
condition and instead do an assignment to a local
'union mips16e_instruction' variable's 'full' member before the if
statement and use this variable in the if condition.

This is the error message reported by clang:
arch/mips/kernel/branch.c:38:8: error: cast to union type from type 'unsigned short' not present in union
                if (((union mips16e_instruction)inst).ri.opcode
                     ^                          ~~~~

The changed code can be compiled successfully by both gcc and clang.

Signed-off-by: Toma Tabacu <toma.tabacu@imgtec.com>
Signed-off-by: Daniel Sanders <daniel.sanders@imgtec.com>
Cc: Andreas Herrmann <andreas.herrmann@caviumnetworks.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Manuel Lauss <manuel.lauss@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9312/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:21:46 +02:00
Kevin Cernekee 9127dc478c MIPS: Let __dt_register_buses accept a single bus type
Some machines only have one bus type to register (e.g. "simple-bus").

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: f.fainelli@gmail.com
Cc: jaedon.shin@gmail.com
Cc: abrestic@chromium.org
Cc: tglx@linutronix.de
Cc: jason@lakedaemon.net
Cc: jogo@openwrt.org
Cc: arnd@arndb.de
Cc: computersforpeace@gmail.com
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8845/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:21:38 +02:00
Deng-Cheng Zhu 262f1c9291 MIPS: csrc-sb1250: Implement read_sched_clock
Use sb1250 hpt for sched_clock source. This implementation will give high
resolution cputime accounting.

Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: macro@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9488/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:21:33 +02:00
Deng-Cheng Zhu 0dc886aba2 MIPS: csrc-sb1250: Remove FSF mail address from GPL notice
This is to make checkpatch.pl happy for the next patch. It would otherwise
say --

ERROR: Do not include the paragraph about writing to the Free Software
Foundation's mailing address from the sample GPL notice. The FSF has
changed addresses in the past, and may do so again. Linux already includes
a copy of the GPL.

Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: macro@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9487/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:21:33 +02:00
Deng-Cheng Zhu 02710fc851 MIPS: csrc-sb1250: Extract hpt cycle acquisition from sb1250_hpt_read
This is to prepare for the upcoming read_sched_clock implementation, which
will also need to get cycles from the high precision timer.

Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: macro@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9486/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:21:33 +02:00
Deng-Cheng Zhu a6071af914 MIPS: cevt-txx9: Implement read_sched_clock
Use txx9 up-counter for sched_clock source. This implementation will give
high resolution cputime accounting.

Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: macro@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9484/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:21:30 +02:00
Deng-Cheng Zhu 7cb24b7003 MIPS: csrc-ioasic: Implement read_sched_clock
Use DEC I/O ASIC's free-running counter for sched_clock source. This
implementation will give high resolution cputime accounting.

Acked-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: macro@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9482/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:21:28 +02:00
Deng-Cheng Zhu 317adb12e5 MIPS: csrc-ioasic: Remove FSF mail address from GPL notice
This is to make checkpatch.pl happy for the next patch. It would otherwise
say --

ERROR: Do not include the paragraph about writing to the Free Software
Foundation's mailing address from the sample GPL notice. The FSF has
changed addresses in the past, and may do so again. Linux already includes
a copy of the GPL.

Acked-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: macro@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9481/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:21:28 +02:00
Deng-Cheng Zhu 27acdea8fe MIPS: csrc-bcm1480: Implement read_sched_clock
Use the ZBbus cycle counter for sched_clock source. This implementation
will give high resolution cputime accounting.

Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: macro@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9480/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:21:27 +02:00
Deng-Cheng Zhu 788049e2d5 MIPS: csrc-bcm1480: Remove FSF mail address from GPL notice
This is to make checkpatch.pl happy for the next patch. It would otherwise
say --

ERROR: Do not include the paragraph about writing to the Free Software
Foundation's mailing address from the sample GPL notice. The FSF has
changed addresses in the past, and may do so again. Linux already includes
a copy of the GPL.

Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: macro@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9479/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:21:27 +02:00
Deng-Cheng Zhu e9cef549c3 MIPS: csrc-r4k: Implement read_sched_clock
Use c0 count register for sched_clock source. This implementation will give
high resolution cputime accounting.

Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: macro@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9478/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:21:27 +02:00
James Hogan e934945db7 MIPS, ttyFDC: Add early FDC console support
Add support for early console of MIPS Fast Debug Channel (FDC) on
channel 1 with a call very early from the MIPS setup_arch().

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9145/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-31 12:04:12 +02:00
James Hogan e38df288a9 MIPS: idle: Workaround wait + FDC problems
On certain cores (namely proAptiv and P5600) incoming data via a Fast
Debug Channel (FDC) while the core is blocked on a wait instruction will
cause the wait not to wake up even when another interrupt is received.
This makes an idle target stop as soon as you send FDC data to it, until
the debug probe interrupts it and restarts the wait instruction.

This is worked around by avoiding using r4k_wait on these cores if
CONFIG_MIPS_EJTAG_FDC_TTY is enabled (which would imply the user intends
to use the FDC).

[ralf@linux-mips.org: Fix conflict.]

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9144/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-31 12:04:12 +02:00
James Hogan 8f7ff02796 MIPS: Read CPU IRQ line that FDC to routed to
Read the CPU IRQ line reportedly used for the Fast Debug Channel (FDC)
interrupt from the IntCtl register and store it in cp0_fdc_irq where
platform implementations of the new weak platform function
get_c0_fdc_int() can refer to it.

[ralf@linux-mips.org: Fixed conflict.]

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/9140/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-31 12:04:12 +02:00
James Hogan 9b3274bd58 MIPS: Add arch CDMM definitions and probing
Add architectural definitions and probing for the MIPS Common Device
Memory Map (CDMM) region. When supported and enabled at a particular
physical address, this region allows some number of per-CPU devices to
be discovered and controlled via MMIO.

A bit exists in Config3 to determine whether the feature is present, and
a CDMMBase CP0 register allows the region to be enabled at a particular
physical address.

[ralf@linux-mips.org: Sort conflict with other patches.]

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9178/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-31 12:04:12 +02:00
James Hogan 4a91d8fb61 MIPS: Allow shared IRQ for timer & perf counter
Before release 2 of the architecture there weren't separate interrupt
pending bits for the local CPU interrupts (timer & perf counter
overflow), so when they were connected to the same interrupt line the
timer handler had to call the performance counter handler before knowing
whether a timer interrupt was actually pending.

Now another CPU local interrupt, for the Fast Debug Channel (FDC), can
also be routed to an arbitrary interrupt line. It isn't scalable to keep
adding cross-calls between handlers for these cases of shared interrupt
lines, especially since the FDC could in theory share its interrupt line
with the performance counter, timer, or both.

Fortunately since release 2 of the architecture separate interrupt
pending bits do exist in the Cause register. This allows local
interrupts which share an interrupt line to have separate handlers using
IRQF_SHARED. Unfortunately they can't easily have their own irqchip as
there is no generic way to individually mask them.

Enable this sharing to happen by removing the special case for when the
perf count shares an IRQ with the timer. cp0_perfcount_irq and
cp0_compare_irq can then be set to the same value with shared interrupt
handlers registered for both of them.

Pre-R2 code should be unaffected. cp0_perfcount_irq will always be -1
and the timer handler will contnue to call into the perf counter
handler.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9131/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-31 12:04:12 +02:00
James Hogan a1ec0e1883 MIPS: perf: Allow sharing IRQ with timer
When requesting the performance counter overflow interrupt, pass flags
which are compatible with the cevt-r4k driver, in particular
IRQF_SHARED so that the two handlers can share the same IRQ. This is
possible since release 2 of the architecture where there are separate
pending interrupt bits for the timer interrupt and the performance
counter interrupt.

This will be necessary since the FDC interrupt can also be arbitrarily
routed to a CPU interrupt, possibly sharing with the timer, the
performance counters, or both, and it isn't scalable to have all the
handlers able to call other handlers that may be on the same IRQ line.

Shared handlers must also have a unique device pointer so they can be
individually removed, so &mipspmu is now passed in for that instead of
NULL.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9129/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-31 12:04:12 +02:00
Ralf Baechle f0c5b8944b MIPS: cevt-r4k: Cleanup c0_compare_interrupt.
The attempt to get gcc to generate best possible code turned
c0_compare_interrupt() into a bit of Italian pasta code.  Tweak for
sanity.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-31 12:04:12 +02:00
James Hogan 7dfe819803 MIPS: cevt-r4k: Make interrupt handler shared
Make the cevt-r4k interrupt handler shared so that other interrupt
handlers (specifically the performance counter overflow handler and fast
debug channel interrupt handler) can share the same interrupt line.

This simply imvolves returning IRQ_NONE when no timer interrupt has been
handled to allow other handlers to run, and passing IRQF_SHARED when
setting up the IRQ handler so that other handlers (with compatible
flags) can be registered.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9128/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-31 12:04:12 +02:00
James Hogan 7eca5b1460 MIPS: Remove redundant IPTI==IPPCI logic
The situation where the timer interrupt is on the same line as the
performance counter interrupt is handled in per_cpu_trap_init() by
setting cp0_perfcount_irq to -1, so there is no need to duplicate the
logic conditional upon cp0_perfcount_irq >= 0 in perf
(init_hw_perf_events()) and oprofile (mipsxx_init()).

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9125/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-31 12:04:12 +02:00
James Hogan 3ba5040af0 MIPS: cevt-r4k: Use CAUSEF_TI, CAUSEF_PCI constants
Use CAUSEF_TI and CAUSEF_PCI constants from asm/mipsregs.h rather than
the magic values (1 << 30) and (1 << 26).

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9124/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-31 12:04:12 +02:00
James Hogan 19971c0bcb MIPS: cevt-r4k: Move handle_perf_irq() out of header
Long ago, commit 8531a35e5e ("[MIPS] SMTC: Fix SMTC dyntick support.")
moved handle_perf_irq() out of cevt-r4k.c into a header so it could be
shared with cevt-smtc.c.

Slightly less long ago, commit b633648c5a ("MIPS: MT: Remove SMTC
support") removed all traces of SMTC support, including cevt-smtc.c,
leaving cevt-r4k.c once again the sole user of handle_perf_irq(),
therefore move it back into cevt-r4k.c from the header.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9123/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-31 12:04:12 +02:00
James Hogan 539cb89fbd MIPS: KVM: Add base guest MSA support
Add base code for supporting the MIPS SIMD Architecture (MSA) in MIPS
KVM guests. MSA cannot yet be enabled in the guest, we're just laying
the groundwork.

As with the FPU, whether the guest's MSA context is loaded is stored in
another bit in the fpu_inuse vcpu member. This allows MSA to be disabled
when the guest disables it, but keeping the MSA context loaded so it
doesn't have to be reloaded if the guest re-enables it.

New assembly code is added for saving and restoring the MSA context,
restoring only the upper half of the MSA context (for if the FPU context
is already loaded) and for saving/clearing and restoring MSACSR (which
can itself cause an MSA FP exception depending on the value). The MSACSR
is restored before returning to the guest if MSA is already enabled, and
the existing FP exception die notifier is extended to catch the possible
MSA FP exception and step over the ctcmsa instruction.

The helper function kvm_own_msa() is added to enable MSA and restore
the MSA context if it isn't already loaded, which will be used in a
later patch when the guest attempts to use MSA for the first time and
triggers an MSA disabled exception.

The existing FPU helpers are extended to handle MSA. kvm_lose_fpu()
saves the full MSA context if it is loaded (which includes the FPU
context) and both kvm_lose_fpu() and kvm_drop_fpu() disable MSA.

kvm_own_fpu() also needs to lose any MSA context if FR=0, since there
would be a risk of getting reserved instruction exceptions if CU1 is
enabled and we later try and save the MSA context. We shouldn't usually
hit this case since it will be handled when emulating CU1 changes,
however there's nothing to stop the guest modifying the Status register
directly via the comm page, which will cause this case to get hit.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
2015-03-27 21:25:19 +00:00
James Hogan 98e91b8457 MIPS: KVM: Add base guest FPU support
Add base code for supporting FPU in MIPS KVM guests. The FPU cannot yet
be enabled in the guest, we're just laying the groundwork.

Whether the guest's FPU context is loaded is stored in a bit in the
fpu_inuse vcpu member. This allows the FPU to be disabled when the guest
disables it, but keeping the FPU context loaded so it doesn't have to be
reloaded if the guest re-enables it.

An fpu_enabled vcpu member stores whether userland has enabled the FPU
capability (which will be wired up in a later patch).

New assembly code is added for saving and restoring the FPU context, and
for saving/clearing and restoring FCSR (which can itself cause an FP
exception depending on the value). The FCSR is restored before returning
to the guest if the FPU is already enabled, and a die notifier is
registered to catch the possible FP exception and step over the ctc1
instruction.

The helper function kvm_lose_fpu() is added to save FPU context and
disable the FPU, which is used when saving hardware state before a
context switch or KVM exit (the vcpu_get_regs() callback).

The helper function kvm_own_fpu() is added to enable the FPU and restore
the FPU context if it isn't already loaded, which will be used in a
later patch when the guest attempts to use the FPU for the first time
and triggers a co-processor unusable exception.

The helper function kvm_drop_fpu() is added to discard the FPU context
and disable the FPU, which will be used in a later patch when the FPU
state will become architecturally UNPREDICTABLE (change of FR mode) to
force a reload of [stale] context in the new FR mode.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
2015-03-27 21:25:14 +00:00
James Hogan 64bedffe49 MIPS: Clear [MSA]FPE CSR.Cause after notify_die()
When handling floating point exceptions (FPEs) and MSA FPEs the Cause
bits of the appropriate control and status register (FCSR for FPEs and
MSACSR for MSA FPEs) are read and cleared before enabling interrupts,
presumably so that it doesn't have to go through the pain of restoring
those bits if the process is pre-empted, since writing those bits would
cause another immediate exception while still in the kernel.

The bits aren't normally ever restored again, since userland never
expects to see them set.

However for virtualisation it is necessary for the kernel to be able to
restore these Cause bits, as the guest may have been interrupted in an
FP exception handler but before it could read the Cause bits. This can
be done by registering a die notifier, to get notified of the exception
when such a value is restored, and if the PC was at the instruction
which is used to restore the guest state, the handler can step over it
and continue execution. The Cause bits can then remain set without
causing further exceptions.

For this to work safely a few changes are made:
- __build_clear_fpe and __build_clear_msa_fpe no longer clear the Cause
  bits, and now return from exception level with interrupts disabled
  instead of enabled.
- do_fpe() now clears the Cause bits and enables interrupts after
  notify_die() is called, so that the notifier can chose to return from
  exception without this happening.
- do_msa_fpe() acts similarly, but now actually makes use of the second
  argument (msacsr) and calls notify_die() with the new DIE_MSAFP,
  allowing die notifiers to be informed of MSA FPEs too.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
2015-03-27 21:25:06 +00:00
James Hogan 466aec5f29 Revert "MIPS: Don't assume 64-bit FP registers for context switch"
This reverts commit 02987633df.

The basic premise of the patch was incorrect since MSA context
(including FP state) is saved using st.d which stores two consecutive
64-bit words in memory rather than a single 128-bit word. This means
that even with big endian MSA, the FP state is still in the first 64-bit
word.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9168/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-27 19:42:48 +01:00
Paul Burton ac9ad83bc3 MIPS: prevent FP context set via ptrace being discarded
If a ptracee has not used the FPU and the ptracer sets its FP context
using PTRACE_POKEUSR, PTRACE_SETFPREGS or PTRACE_SETREGSET then that
context will be discarded upon either the ptracee using the FPU or a
further write to the context via ptrace. Prevent this loss by recording
that the task has "used" math once its FP context has been written to.
The context initialisation code that was present for the PTRACE_POKEUSR
case is reused for the other 2 cases to provide consistent behaviour
for the different ptrace requests.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9166/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-27 19:42:47 +01:00
Paul Burton ad70c13a93 MIPS: Ensure FCSR cause bits are clear after invoking FPU emulator
When running the emulator to handle an instruction that raised an FP
unimplemented operation exception, the FCSR cause bits were being
cleared. This is done to ensure that the kernel does not take an FP
exception when later restoring FP context to registers. However, this
was not being done when the emulator is invoked in response to a
coprocessor unusable exception. This happens in 2 cases:

  - There is no FPU present in the system. In this case things were
    OK, since the FP context is never restored to hardware registers
    and thus no FP exception may be raised when restoring FCSR.

  - The FPU could not be configured to the mode required by the task.
    In this case it would be possible for the emulator to set cause
    bits which are later restored to hardware if the task migrates
    to a CPU whose associated FPU does support its mode requirements,
    or if the tasks FP mode requirements change.

Consistently clear the cause bits after invoking the emulator, by moving
the clearing to process_fpemu_return and ensuring this is always called
before the tasks FP context is restored. This will make it easier to
catch further paths invoking the emulator in future, as will be
introduced in further patches.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9165/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-27 19:42:46 +01:00
Paul Burton 091be550a7 MIPS: clear MSACSR cause bits when handling MSA FP exception
Much like for traditional scalar FP exceptions, the cause bits in the
MSACSR register need to be cleared following an MSA FP exception.
Without doing so the exception will simply be raised again whenever
the kernel restores MSACSR from a tasks saved context, leading to
undesirable spurious exceptions. Clear the cause bits from the
handle_msa_fpe function, mirroring the way handle_fpe clears the
cause bits in FCSR.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9164/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-27 19:42:45 +01:00
Paul Burton 631afc65e8 MIPS: Push .set mips64r* into the functions needing it
The {save,restore}_fp_context{,32} functions require that the assembler
allows the use of sdc instructions on any FP register, and this is
acomplished by setting the arch to mips64r2 or mips64r6
(using MIPS_ISA_ARCH_LEVEL_RAW).

However this has the effect of enabling the assembler to use mips64
instructions in the expansion of pseudo-instructions. This was done in
the (now-reverted) commit eec43a224c "MIPS: Save/restore MSA context
around signals" which led to my mistakenly believing that there was an
assembler bug, when in reality the assembler was just emitting mips64
instructions. Avoid the issue for future commits which will add code to
r4k_fpu.S by pushing the .set MIPS_ISA_ARCH_LEVEL_RAW directives into
the functions that require it, and remove the spurious assertion
declaring the assembler bug.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
[james.hogan@imgtec.com: Rebase on v4.0-rc1 and reword commit message to
 reflect use of MIPS_ISA_ARCH_LEVEL_RAW]
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9612/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-27 19:42:42 +01:00
Alex Dowad e2c5aaa5fd mips: copy_thread(): rename 'arg' argument to 'kthread_arg'
The 'arg' argument to copy_thread() is only ever used when forking a new
kernel thread. Hence, rename it to 'kthread_arg' for clarity (and consistency
with do_fork() and other arch-specific implementations of copy_thread()).

Signed-off-by: Alex Dowad <alexinbeijing@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Alex Smith <alex@alex-smith.me.uk>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Eunbong Song <eunb.song@samsung.com>
Cc: linux-mips@linux-mips.org (open list:MIPS)
Patchwork: https://patchwork.linux-mips.org/patch/9546/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-24 15:15:34 +01:00
Steven J. Hill c5b367835c MIPS: Add support for XPA.
Add support for extended physical addressing (XPA) so that
32-bit platforms can access equal to or greater than 40 bits
of physical addresses.

NOTE:
      1) XPA and EVA are not the same and cannot be used
         simultaneously.
      2) If you configure your kernel for XPA, the PTEs
         and all address sizes become 64-bit.
      3) Your platform MUST have working HIGHMEM support.

Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9355/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-19 17:39:49 +01:00
Rusty Russell 8dd928915a mips: fix up obsolete cpu function usage.
Thanks to spatch, plus manual removal of "&*".  Then a sweep for
for_each_cpu_mask => for_each_cpu.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: linux-mips@linux-mips.org
2015-03-05 15:25:06 +10:30
Linus Torvalds a135c717d5 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS updates from Ralf Baechle:
 "This is the main pull request for MIPS:

   - a number of fixes that didn't make the 3.19 release.

   - a number of cleanups.

   - preliminary support for Cavium's Octeon 3 SOCs which feature up to
     48 MIPS64 R3 cores with FPU and hardware virtualization.

   - support for MIPS R6 processors.

     Revision 6 of the MIPS architecture is a major revision of the MIPS
     architecture which does away with many of original sins of the
     architecture such as branch delay slots.  This and other changes in
     R6 require major changes throughout the entire MIPS core
     architecture code and make up for the lion share of this pull
     request.

   - finally some preparatory work for eXtendend Physical Address
     support, which allows support of up to 40 bit of physical address
     space on 32 bit processors"

     [ Ahh, MIPS can't leave the PAE brain damage alone.  It's like
       every CPU architect has to make that mistake, but pee in the snow
       by changing the TLA.  But whether it's called PAE, LPAE or XPA,
       it's horrid crud   - Linus ]

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (114 commits)
  MIPS: sead3: Corrected get_c0_perfcount_int
  MIPS: mm: Remove dead macro definitions
  MIPS: OCTEON: irq: add CIB and other fixes
  MIPS: OCTEON: Don't do acknowledge operations for level triggered irqs.
  MIPS: OCTEON: More OCTEONIII support
  MIPS: OCTEON: Remove setting of processor specific CVMCTL icache bits.
  MIPS: OCTEON: Core-15169 Workaround and general CVMSEG cleanup.
  MIPS: OCTEON: Update octeon-model.h code for new SoCs.
  MIPS: OCTEON: Implement DCache errata workaround for all CN6XXX
  MIPS: OCTEON: Add little-endian support to asm/octeon/octeon.h
  MIPS: OCTEON: Implement the core-16057 workaround
  MIPS: OCTEON: Delete unused COP2 saving code
  MIPS: OCTEON: Use correct instruction to read 64-bit COP0 register
  MIPS: OCTEON: Save and restore CP2 SHA3 state
  MIPS: OCTEON: Fix FP context save.
  MIPS: OCTEON: Save/Restore wider multiply registers in OCTEON III CPUs
  MIPS: boot: Provide more uImage options
  MIPS: Remove unneeded #ifdef __KERNEL__ from asm/processor.h
  MIPS: ip22-gio: Remove legacy suspend/resume support
  mips: pci: Add ifdef around pci_proc_domain
  ...
2015-02-21 19:41:38 -08:00
Aleksey Makarov 69f7cd4724 MIPS: OCTEON: Delete unused COP2 saving code
Commit 2c952e06e4 ("MIPS: Move cop2 save/restore to switch_to()")
removes assembler code to store COP2 registers.  Commit
a36d8225bc ("MIPS: OCTEON: Enable use of FPU") mistakenly
restores it

Fixes: a36d8225bc ("MIPS: OCTEON: Enable use of FPU")
Signed-off-by: Aleksey Makarov <aleksey.makarov@auriga.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: David Daney <david.daney@cavium.com>
Patchwork: https://patchwork.linux-mips.org/patch/8937/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-02-20 15:30:23 +01:00
Chandrakala Chavva 2d98cae6e3 MIPS: OCTEON: Use correct instruction to read 64-bit COP0 register
Use dmfc0/dmtc0 instructions for reading CvmMemCtl COP0 register,
its a 64-bit wide.

Signed-off-by: Chandrakala Chavva <cchavva@caviumnetworks.com>
Signed-off-by: Aleksey Makarov <aleksey.makarov@auriga.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: David Daney <david.daney@cavium.com>
Patchwork: https://patchwork.linux-mips.org/patch/8936/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-02-20 15:29:36 +01:00
David Daney 6b3a287e63 MIPS: OCTEON: Save and restore CP2 SHA3 state
Allocate new save space, and then save/restore the registers if
OCTEON III.

Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: Aleksey Makarov <aleksey.makarov@auriga.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8935/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-02-20 15:29:08 +01:00
David Daney d6e41525e3 MIPS: OCTEON: Fix FP context save.
It wasn't being saved on task switch.

Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: Aleksey Makarov <aleksey.makarov@auriga.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8934/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-02-20 15:28:51 +01:00
David Daney ac655fb762 MIPS: OCTEON: Save/Restore wider multiply registers in OCTEON III CPUs
The wide multiplier is twice as wide, so we need to save twice as much
state.  Detect the multiplier type (CPU type) at start up and install
model specific handlers.

[aleksey.makarov@auriga.com:
	conflict resolution,
	support for old compilers]

Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: Leonid Rosenboim <lrosenboim@caviumnetworks.com>
Signed-off-by: Aleksey Makarov <aleksey.makarov@auriga.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8933/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-02-20 15:28:29 +01:00
Steven J. Hill a5770df095 MIPS: Add set/clear CP0 macros for PageGrain register
Build set and clear macros for the PageGrain register.

Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9289/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-02-20 12:55:18 +01:00
Ralf Baechle 661af35e5f Merge branch 'mipsr6-for-3.20' of git://git.linux-mips.org/pub/scm/mchandras/linux into mips-for-linux-next 2015-02-19 16:00:34 +01:00
James Hogan ca5d25642e MIPS: Export MSA functions used by lose_fpu(1) for KVM
Export the _save_msa asm function used by the lose_fpu(1) macro to GPL
modules so that KVM can make use of it when it is built as a module.

This fixes the following build error when CONFIG_KVM=m and
CONFIG_CPU_HAS_MSA=y due to commit f798217dfd ("KVM: MIPS: Don't leak
FPU/DSP to guest"):

ERROR: "_save_msa" [arch/mips/kvm/kvm.ko] undefined!

Fixes: f798217dfd (KVM: MIPS: Don't leak FPU/DSP to guest)
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 3.15+
Patchwork: https://patchwork.linux-mips.org/patch/9261/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-02-19 15:59:44 +01:00
James Hogan 3ce465e04b MIPS: Export FP functions used by lose_fpu(1) for KVM
Export the _save_fp asm function used by the lose_fpu(1) macro to GPL
modules so that KVM can make use of it when it is built as a module.

This fixes the following build error when CONFIG_KVM=m due to commit
f798217dfd ("KVM: MIPS: Don't leak FPU/DSP to guest"):

ERROR: "_save_fp" [arch/mips/kvm/kvm.ko] undefined!

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Fixes: f798217dfd (KVM: MIPS: Don't leak FPU/DSP to guest)
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 3.10+
Patchwork: https://patchwork.linux-mips.org/patch/9260/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-02-19 15:58:51 +01:00
Markos Chandras 46490b5725 MIPS: kernel: elf: Improve the overall ABI and FPU mode checks
The previous implementation did not cover all possible FPU combinations
and it silently allowed ABI incompatible objects to be loaded with the
wrong ABI. For example, the previous logic would set the FP_64 ABI as
the matching ABI for an FP_XX object combined with an FP_64A object.
This was wrong, and the matching ABI should have been FP_64A.
The previous logic is now replaced with a new one which determines
the appropriate FPU mode to be used rather than the FP ABI. This has
the advantage that the entire logic is much simpler since it is the FPU
mode we are interested in rather than the FP ABI resulting to code
simplifications. This also removes the now obsolete FP32XX_HYBRID_FPRS
option.

Cc: Matthew Fortune <Matthew.Fortune@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:39 +00:00
Markos Chandras 13e45f0957 MIPS: kernel: process: Do not allow FR=0 on MIPS R6
A prctl() call to set FR=0 for MIPS R6 should not be allowed
since FR=1 is the only option for R6 cores.

Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Matthew Fortune <matthew.fortune@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:38 +00:00
Markos Chandras 7c151d3d5d MIPS: Make use of the ERETNC instruction on MIPS R6
The ERETNC instruction, introduced in MIPS R5, is similar to the ERET
one, except it does not clear the LLB bit in the LLADDR register.
This feature is necessary to safely emulate R2 LL/SC instructions.
However, on context switches, we need to clear the LLAddr/LLB bit
in order to make sure that an SC instruction from the new thread
will never succeed if it happens to interrupt an LL operation on the
same address from the previous thread.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:37 +00:00
Leonid Yegoshin b0a668fb20 MIPS: kernel: mips-r2-to-r6-emul: Add R2 emulator for MIPS R6
MIPS R6 removed quite a few R2 instructions. However, there
is plenty of <R6 userland code so we add an in-kernel emulator
so we can still be able to execute all R2 userland out there.

The emulator comes with a handy debugfs under /mips/ directory
(r2-emul-stats) to provide some basic statistics of the
instructions that are being emulated.

Below are some statistics from booting a minimal buildroot image:

Instruction     Total   BDslot
------------------------------
movs            236969  0
hilo            56686   0
muls            55279   0
divs            10941   0
dsps            0       0
bops            1       0
traps           0       0
fpus            0       0
loads           214981  17
stores          103364  0
llsc            56898   0
dsemul          150418  0
jr              370158
bltzl           43
bgezl           1594
bltzll          0
bgezll          0
bltzal          39
bgezal          39
beql            14503
bnel            138741
blezl           0
bgtzl           3988

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:37 +00:00
Markos Chandras 5aed9da128 MIPS: Add LLB bit and related feature for the Config 5 CP0 register
The LLBIT (bit 4) in the Config5 CP0 register indicates the software
availability of the Load-Linked bit. This bit is only set by hardware
and it has the following meaning:

0: LLB functionality is not supported
1: LLB functionality is supported. The following feature are also
supported:

- ERETNC instruction. Similar to ERET but it does not clear the LLB
bit in the LLAddr register.
- CP0 LLAddr/LLB bit must be set
- LLbit is software accessible through the LLAddr[0]

This will be used later on to emulate R2 LL/SC instructions.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:36 +00:00
Markos Chandras 28d6f93d20 MIPS: Emulate the new MIPS R6 BNEZC and JIALC instructions
MIPS R6 uses the <R6 sdc2 opcode for the new BNEZC and JIALC instructions

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:35 +00:00
Markos Chandras 69b9a2fd05 MIPS: Emulate the new MIPS R6 BEQZC and JIC instructions
MIPS R6 uses the <R6 ldc2 opcode for the new BEQZC and JIC instructions

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:35 +00:00
Markos Chandras 84fef63012 MIPS: Emulate the new MIPS R6 BALC instruction
MIPS R6 uses the <R6 swc2 opcode for the new BALC instructions.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:35 +00:00
Markos Chandras 10d962d534 MIPS: Emulate the new MIPS R6 BNVC, BNEC and BNEZLAC instructions
MIPS R6 uses the <R6 DADDI opcode for the new BNVC, BNEC and
BNEZLAC instructions.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:34 +00:00
Markos Chandras c893ce38b2 MIPS: Emulate the new MIPS R6 BOVC, BEQC and BEQZALC instructions
MIPS R6 uses the <R6 ADDI opcode for the new BOVC, BEQC and
BEQZALC instructions.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:34 +00:00
Markos Chandras 8467ca0122 MIPS: Emulate the new MIPS R6 branch compact (BC) instruction
MIPS R6 uses the <R6 LWC2 opcode for the new BC instruction.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:34 +00:00
Markos Chandras f1b44067c1 MIPS: Emulate the new MIPS R6 B{L,G}T{Z,}{AL,}C instructions
MIPS R6 added the following four instructions which share the
BGTZ and BGTZL opcode:

BLTZALC: Compact branch-and-link if GPR rt is < to zero
BGTZALC: Compact branch-and-link if GPR rt is > to zero
BLTZL  : Compact branch if GPR rt is < to zero
BGTZL  : Compact branch if GPR rt is > to zero
BLTC   : Compact branch if GPR rs is less than GPR rt
BLTUC  : Similar to BLTC but unsigned

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:33 +00:00
Markos Chandras a8ff66f52d MIPS: Emulate the new MIPS R6 B{L,G}Ε{Z,}{AL,}C instructions
MIPS R6 added the following four instructions which share the
BLEZ and BLEZL opcodes:

BLEZALC: Compact branch-and-link if GPR rt is <= to zero
BGEZALC: Compact branch-and-link if GPR rt is >= to zero
BLEZC  : Compact branch if GPR rt is <= to zero
BGEZC  : Compact branch if GPR rt is >= to zero
BGEC   : Compact branch if GPR rs is less than or equal to GPR rt
BGEUC  : Similar to BGEC but unsigned.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:33 +00:00
Markos Chandras c8a34581ec MIPS: Emulate the BC1{EQ,NE}Z FPU instructions
MIPS R6 introduced the following two branch instructions for COP1:

BC1EQZ: Branch if Cop1 (FPR) Register Bit 0 is Equal to Zero
BC1NEZ: Branch if Cop1 (FPR) Register Bit 0 is Not Equal to Zero

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:32 +00:00
Markos Chandras 319824eabc MIPS: kernel: branch: Do not emulate the branch likelies on MIPS R6
MIPS R6 removed the BLTZL, BGEZL, BLTZAL, BGEZAL, BEQL, BNEL, BLEZL,
BGTZL branch likely instructions so we must not try to emulate them on
MIPS R6 if the R2-to-R6 emulator is not present.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:32 +00:00
Markos Chandras 5f9f41c474 MIPS: kernel: Prepare the JR instruction for emulation on MIPS R6
The MIPS R6 JR instruction is an alias to the JALR one, so it may
need emulation for non-R6 userlands.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:31 +00:00
Markos Chandras fee313d4b8 MIPS: kernel: syscall: Set the appropriate ISA level for MIPS R6
MIPS R6 changed the opcodes for LL/SC instructions so we need to set
the appropriate ISA level.

Cc: Matthew Fortune <Matthew.Fortune@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:29 +00:00
Leonid Yegoshin 0593a44c64 MIPS: kernel: unaligned: Add support for the MIPS R6
The load/store unaligned instructions have been removed in MIPS R6
so we need to re-implement the related macros using the regular
load/store instructions. Moreover, the load/store from coprocessor 2
instructions have been reallocated in Release 6 so we will handle them
in the emulator instead.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:28 +00:00
Markos Chandras acac4108df MIPS: kernel: cps-vec: Replace "addi" with "addiu"
The "addi" instruction will trap on overflows which is not something
we need in this code, so we replace that with "addiu".

Link: http://www.linux-mips.org/archives/linux-mips/2015-01/msg00430.html
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: <stable@vger.kernel.org> # v3.15+
Cc: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:28 +00:00
Markos Chandras 938c12824b MIPS: kernel: genex: Set correct ISA level
The jr instruction opcode has changed in R6 so make sure
the correct ISA level is set prior using that instruction.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:28 +00:00
Leonid Yegoshin 8d5b9b771e MIPS: kernel: r4k_fpu: Add support for MIPS R6
Add the MIPS R6 related preprocessor definitions for FPU signal
related functions. MIPS R6 only has FR=1 so avoid checking that
bit on the C0/Status register.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:27 +00:00
Leonid Yegoshin 207083b1da MIPS: kernel: r4k_switch: Add support for MIPS R6
Add the MIPS R6 related preprocessor definitions for save/restore
FPU related functions. We also set the appropriate ISA level
so the final return instruction "jr ra" will produce the correct
opcode on R6.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:27 +00:00
Leonid Yegoshin 9c7d576868 MIPS: kernel: traps: Add MIPS R6 related definitions
Add MIPS R6 support to cache and ftlb exceptions, as well as
to the hwrena and ebase register configuration.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:27 +00:00
Markos Chandras 515a6393db MIPS: kernel: proc: Add MIPS R6 support to /proc/cpuinfo
Print 'mips64r6' and/or 'mips32r6' if the kernel is running on
a MIPS R6 core.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:26 +00:00
Markos Chandras 6ebb496ffc MIPS: kernel: entry.S: Add MIPS R6 related definitions
The instruction hazard barrier in the form of:

jr.hb	ra
nop

is valid on MIPS R6 as well.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:26 +00:00
Leonid Yegoshin 8b8aa636f0 MIPS: kernel: cpu-probe.c: Add support for MIPS R6
Add MIPS R6 support when decoding the config0 c0 register.
Also add MIPS R6 support when examining the ebase c0 register
to get the core number and when getting the shadow set number
from the srsctl c0 register.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:25 +00:00
Leonid Yegoshin 54dac95083 MIPS: kernel: cevt-r4k: Add MIPS R6 to the c0_compare_interrupt handler
Just like MIPS R2, in MIPS R6 it is possible to determine if a
timer interrupt has happened or not.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:25 +00:00
Leonid Yegoshin 180b1e3bfe MIPS: kernel: cpu-bugs64: Do not check R6 cores for existing 64-bit bugs
The current HW bugs checked in cpu-bugs64, do not apply to R6 cores
and they cause compilation problems due to removed <R6 instructions,
so do not check for them for the time being.

Reviewed-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:24 +00:00
Markos Chandras a7e07b1ae5 MIPS: asm: spram: Add new symbol for MIPS scratch pad storage
MIPS R6, just like MIPS R2, have scratch pad storage, so add a new
symbol which is selected by MIPS R2 and R6.

Link: http://www.linux-mips.org/archives/linux-mips/2015-01/msg00389.html
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:20 +00:00
Markos Chandras 4e0748f5be MIPS: Use generic checksum functions for MIPS R6
The following instructions have been removed from MIPS R6

ulw, ulh, swl, lwr, lwl, swr.

However, all of them are used in the MIPS specific checksum implementation.
As a result of which, we will use the generic checksum on MIPS R6

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:19 +00:00
Leonid Yegoshin b2498af56a MIPS: Add MIPS generic QEMU probe support
Add a case in cpu_probe_mips for the MIPS generic QEMU processor ID.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-16 10:01:24 +00:00
Leonid Yegoshin 4695089f03 MIPS: Add cases for CPU_QEMU_GENERIC
Add a CPU_QEMU_GENERIC case to various switch statements.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-16 10:01:24 +00:00
Markos Chandras ed4cbc81ad MIPS: HTW: Prevent accidental HTW start due to nested htw_{start, stop}
activate_mm() and switch_mm() call get_new_mmu_context() which in turn
can enable the HTW before the entryhi is changed with the new ASID.
Since the latter will enable the HTW in local_flush_tlb_all(),
then there is a small timing window where the HTW is running with the
new ASID but with an old pgd since the TLBMISS_HANDLER_SETUP_PGD
hasn't assigned a new one yet. In order to prevent that, we introduce a
simple htw counter to avoid starting HTW accidentally due to nested
htw_{start,stop}() sequences. Moreover, since various IPI calls can
enforce TLB flushing operations on a different core, such an operation
may interrupt another htw_{stop,start} in progress leading inconsistent
updates of the htw_seq variable. In order to avoid that, we disable the
interrupts whenever we update that variable.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: <stable@vger.kernel.org> # 3.17+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9118/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-02-16 10:55:26 +01:00
Andrey Ryabinin cb9e3c292d mm: vmalloc: pass additional vm_flags to __vmalloc_node_range()
For instrumenting global variables KASan will shadow memory backing memory
for modules.  So on module loading we will need to allocate memory for
shadow and map it at address in shadow that corresponds to the address
allocated in module_alloc().

__vmalloc_node_range() could be used for this purpose, except it puts a
guard hole after allocated area.  Guard hole in shadow memory should be a
problem because at some future point we might need to have a shadow memory
at address occupied by guard hole.  So we could fail to allocate shadow
for module_alloc().

Now we have VM_NO_GUARD flag disabling guard page, so we need to pass into
__vmalloc_node_range().  Add new parameter 'vm_flags' to
__vmalloc_node_range() function.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:42 -08:00
Andy Lutomirski f56141e3e2 all arches, signal: move restart_block to struct task_struct
If an attacker can cause a controlled kernel stack overflow, overwriting
the restart block is a very juicy exploit target.  This is because the
restart_block is held in the same memory allocation as the kernel stack.

Moving the restart block to struct task_struct prevents this exploit by
making the restart_block harder to locate.

Note that there are other fields in thread_info that are also easy
targets, at least on some architectures.

It's also a decent simplification, since the restart code is more or less
identical on all architectures.

[james.hogan@imgtec.com: metag: align thread_info::supervisor_stack]
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: David Miller <davem@davemloft.net>
Acked-by: Richard Weinberger <richard@nod.at>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Steven Miao <realmz6@gmail.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Tested-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chen Liqin <liqin.linux@gmail.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12 18:54:12 -08:00
Paul Burton 9791554b45 MIPS,prctl: add PR_[GS]ET_FP_MODE prctl options for MIPS
Userland code may be built using an ABI which permits linking to objects
that have more restrictive floating point requirements. For example,
userland code may be built to target the O32 FPXX ABI. Such code may be
linked with other FPXX code, or code built for either one of the more
restrictive FP32 or FP64. When linking with more restrictive code, the
overall requirement of the process becomes that of the more restrictive
code. The kernel has no way to know in advance which mode the process
will need to be executed in, and indeed it may need to change during
execution. The dynamic loader is the only code which will know the
overall required mode, and so it needs to have a means to instruct the
kernel to switch the FP mode of the process.

This patch introduces 2 new options to the prctl syscall which provide
such a capability. The FP mode of the process is represented as a
simple bitmask combining a number of mode bits mirroring those present
in the hardware. Userland can either retrieve the current FP mode of
the process:

  mode = prctl(PR_GET_FP_MODE);

or modify the current FP mode of the process:

  err = prctl(PR_SET_FP_MODE, new_mode);

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Matthew Fortune <matthew.fortune@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8899/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-02-12 12:30:29 +01:00
James Hogan ae58d882bf MIPS: cevt-r4k: Drop GIC special case
The cevt-r4k driver used to call into the GIC driver to find whether the
timer was pending, but only with External Interrupt Controller (EIC)
mode, where the Cause.IP bits can't be used as they encode the interrupt
priority level (Cause.RIPL) instead.

However commit e9de688dac ("irqchip: mips-gic: Support local
interrupts") changed the condition from cpu_has_veic to gic_present.
This fails on cores such as P5600 which have a GIC but the local
interrupts aren't routable by the GIC, causing c0_compare_int_usable()
to consider the interrupt unusable so r4k_clockevent_init() fails.

The previous behaviour, added in commit 98b67c37db ("MIPS: Add EIC
support for GIC."), wasn't really correct either as far as I can tell,
since P5600 apparently supports EIC mode too, and in any case the use of
Cause.TI with r2 should have been sufficient anyway since commit
010c108d7a ("MIPS: PowerTV: Fix support for timer interrupts with > 64
external IRQs").

Therefore drop the call into the gic driver altogether, and add a
comment in c0_compare_int_pending() to clarify that Cause.TI does get
checked since MIPS r2.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Fixes: e9de688dac ("irqchip: mips-gic: Support local interrupts")
Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Steven J. Hill <steven.hill@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9077/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-02-05 14:56:53 +01:00
Lars Persson c2d9f17757 MIPS: Fix syscall_get_nr for the syscall exit tracing.
Register 2 is alredy overwritten by the return value when
syscall_trace_leave() is called.

Signed-off-by: Lars Persson <larper@axis.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9187/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-02-04 16:40:09 +01:00
James Hogan 39148e94e3 MIPS: fork: Fix MSA/FPU/DSP context duplication race
There is a race in the MIPS fork code which allows the child to get a
stale copy of parent MSA/FPU/DSP state that is active in hardware
registers when the fork() is called. This is because copy_thread() saves
the live register state into the child context only if the hardware is
currently in use, apparently on the assumption that the hardware state
cannot have been saved and disabled since the initial duplication of the
task_struct. However preemption is certainly possible during this
window.

An example sequence of events is as follows:

1) The parent userland process puts important data into saved floating
   point registers ($f20-$f31), which are then dirty compared to the
   process' stored context.

2) The parent process calls fork() which does a clone system call.

3) In the kernel, do_fork() -> copy_process() -> dup_task_struct() ->
   arch_dup_task_struct() (which uses the weakly defined default
   implementation). This duplicates the parent process' task context,
   which includes a stale version of its FP context from when it was
   last saved, probably some time before (1).

4) At some point before copy_process() calls copy_thread(), such as when
   duplicating the memory map, the process is desceduled. Perhaps it is
   preempted asynchronously, or perhaps it sleeps while blocked on a
   mutex. The dirty FP state in the FP registers is saved to the parent
   process' context and the FPU is disabled.

5) When the process is rescheduled again it continues copying state
   until it gets to copy_thread(), which checks whether the FPU is in
   use, so that it can copy that dirty state to the child process' task
   context. Because of the deschedule however the FPU is not in use, so
   the child process' context is left with stale FP context from the
   last time the parent saved it (some time before (1)).

6) When the new child process is scheduled it reads the important data
   from the saved floating point register, and ends up doing a NULL
   pointer dereference as a result of the stale data.

This use of saved floating point registers across function calls can be
triggered fairly easily by explicitly using inline asm with a current
(MIPS R2) compiler, but is far more likely to happen unintentionally
with a MIPS R6 compiler where the FP registers are more likely to get
used as scratch registers for storing non-fp data.

It is easily fixed, in the same way that other architectures do it, by
overriding the implementation of arch_dup_task_struct() to sync the
dirty hardware state to the parent process' task context *prior* to
duplicating it, rather than copying straight to the child process' task
context in copy_thread(). Note, the FPU hardware is not disabled so the
parent process may continue executing with the live register context,
but now the child process is guaranteed to have an identical copy of it
at that point.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reported-by: Matthew Fortune <matthew.fortune@imgtec.com>
Tested-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9075/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-01-31 00:44:19 +01:00
James Hogan d76e9b9fc5 MIPS: traps: Fix inline asm ctc1 missing .set hardfloat
Commit 842dfc11ea ("MIPS: Fix build with binutils 2.24.51+") in v3.18
enabled -msoft-float and sprinkled ".set hardfloat" where necessary to
use FP instructions. However it missed enable_restore_fp_context() which
since v3.17 does a ctc1 with inline assembly, causing the following
assembler errors on Mentor's 2014.05 toolchain:

{standard input}: Assembler messages:
{standard input}:2913: Error: opcode not supported on this processor: mips32r2 (mips32r2) `ctc1 $2,$31'
scripts/Makefile.build:257: recipe for target 'arch/mips/kernel/traps.o' failed

Fix that to use the new write_32bit_cp1_register() macro so that ".set
hardfloat" is automatically added when -msoft-float is in use.

Fixes 842dfc11ea ("MIPS: Fix build with binutils 2.24.51+")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 3.18+, depends on "MIPS: mipsregs.h: Add write_32bit_cp1_register()"
Patchwork: https://patchwork.linux-mips.org/patch/9173/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-01-30 23:05:04 +01:00
Hemmo Nieminen c7754e7510 MIPS: Fix kernel lockup or crash after CPU offline/online
As printk() invocation can cause e.g. a TLB miss, printk() cannot be
called before the exception handlers have been properly initialized.
This can happen e.g. when netconsole has been loaded as a kernel module
and the TLB table has been cleared when a CPU was offline.

Call cpu_report() in start_secondary() only after the exception handlers
have been initialized to fix this.

Without the patch the kernel will randomly either lockup or crash
after a CPU is onlined and the console driver is a module.

Signed-off-by: Hemmo Nieminen <hemmo.nieminen@iki.fi>
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: stable@vger.kernel.org
Cc: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8953/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-01-29 23:54:07 +01:00
Felix Fietkau a3e6c1eff5 MIPS: IRQ: Fix disable_irq on CPU IRQs
If the irq_chip does not define .irq_disable, any call to disable_irq
will defer disabling the IRQ until it fires while marked as disabled.
This assumes that the handler function checks for this condition, which
handle_percpu_irq does not. In this case, calling disable_irq leads to
an IRQ storm, if the interrupt fires while disabled.

This optimization is only useful when disabling the IRQ is slow, which
is not true for the MIPS CPU IRQ.

Disable this optimization by implementing .irq_disable and .irq_enable

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: stable@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8949/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-01-16 14:03:17 +01:00
James Hogan c3f134fb39 MIPS: smp-mt,smp-cmp: Enable all HW IRQs on secondary CPUs
Commit 18743d2781 ("irqchip: mips-gic: Stop using per-platform mapping
tables") in v3.19-rc1 changed the routing of IPIs through the GIC to go
to the HW0 IRQ pin along with the rest of the GIC interrupts, rather
than to HW1 and HW2 pins.

This breaks SMP boot using the CMP or MT SMP implementations because HW0
doesn't get unmasked when secondary CPUs are initialised so the IPIs
will never interrupt secondary CPUs (nor any other interrupts routed
through the GIC).

Commit ff1e29ade4 ("MIPS: smp-cps: Enable all hardware interrupts on
secondary CPUs") fixed this in advance for the CPS SMP implementation by
unmasking all hardware interrupt lines for secondary CPUs, so lets do
the same for the CMP and MT implementations.

Fixes: 18743d2781 ("irqchip: mips-gic: Stop using per-platform mapping tables")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9025/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-01-16 13:02:40 +01:00
Ed Swierk e967ef022e MIPS: Fix restart of indirect syscalls
When 32-bit MIPS userspace invokes a syscall indirectly via syscall(number,
arg1, ..., arg7), the kernel looks up the actual syscall based on the given
number, shifts the other arguments to the left, and jumps to the syscall.

If the syscall is interrupted by a signal and indicates it needs to be
restarted by the kernel (by returning ERESTARTNOINTR for example), the
syscall must be called directly, since the number is no longer the first
argument, and the other arguments are now staged for a direct call.

Before shifting the arguments, store the syscall number in pt_regs->regs[2].
This gets copied temporarily into pt_regs->regs[0] after the syscall returns.
If the syscall needs to be restarted, handle_signal()/do_signal() copies the
number back to pt_regs->reg[2], which ends up in $v0 once control returns to
userspace.

Signed-off-by: Ed Swierk <eswierk@skyportsystems.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8929/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-01-16 00:35:45 +01:00
James Cowgill fd75a33e00 MIPS: ELF: fix loading o32 binaries on 64-bit kernels
Commit 90cee759f0 ("MIPS: ELF: Set FP mode according to .MIPS.abiflags")
introduced checking of the .MIPS.abiflags ELF section but did so through
the native sized "elfhdr" and "elf_phdr" structures regardless whether the
ELF was actually 32-bit or 64-bit. This produces wrong results when trying
to use a 64-bit kernel to load o32 ELF files.

Change the uses of the generic elf structures to their 32-bit versions.
Since the code bails out on any 64-bit cases, this is OK until they are
implemented.

Fixes: 90cee759f0 ("MIPS: ELF: Set FP mode according to .MIPS.abiflags")
Signed-off-by: James Cowgill <James.Cowgill@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: Maciej W. Rozycki <macro@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/8932/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-01-15 15:59:28 +01:00
Ralf Baechle 389cdc5d35 MIPS: Wire up execveat(2).
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-01-13 15:53:09 +01:00
Jaedon Shin ad8f723afb MIPS: Use phys_addr_t instead of phys_t
Ralf Baechle says:
 "This should have been part of the merge commit c0222ac086 (Merge
  branch 'upstream' of git://git.linux-mips.org/pub/scm/-
  ralf/upstream-linus) but I forgot to mention the need for this in my
  pull request"

Signed-off-by: Jaedon Shin <jaedon.shin@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-12 15:36:13 -08:00
Linus Torvalds c0222ac086 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS updates from Ralf Baechle:
 "This is an unusually large pull request for MIPS - in parts because
  lots of patches missed the 3.18 deadline but primarily because some
  folks opened the flood gates.

   - Retire the MIPS-specific phys_t with the generic phys_addr_t.
   - Improvments for the backtrace code used by oprofile.
   - Better backtraces on SMP systems.
   - Cleanups for the Octeon platform code.
   - Cleanups and fixes for the Loongson platform code.
   - Cleanups and fixes to the firmware library.
   - Switch ATH79 platform to use the firmware library.
   - Grand overhault to the SEAD3 and Malta interrupt code.
   - Move the GIC interrupt code to drivers/irqchip
   - Lots of GIC cleanups and updates to the GIC code to use modern IRQ
     infrastructures and features of the kernel.
   - OF documentation updates for the GIC bindings
   - Move GIC clocksource driver to drivers/clocksource
   - Merge GIC clocksource driver with clockevent driver.
   - Further updates to bring the GIC clocksource driver up to date.
   - R3000 TLB code cleanups
   - Improvments to the Loongson 3 platform code.
   - Convert pr_warning to pr_warn.
   - Merge a bunch of small lantiq and ralink fixes that have been
     staged/lingering inside the openwrt tree for a while.
   - Update archhelp for IP22/IP32
   - Fix a number of issues for Loongson 1B.
   - New clocksource and clockevent driver for Loongson 1B.
   - Further work on clk handling for Loongson 1B.
   - Platform work for Broadcom BMIPS.
   - Error handling cleanups for TurboChannel.
   - Fixes and optimization to the microMIPS support.
   - Option to disable the FTLB.
   - Dump more relevant information on machine check exception
   - Change binfmt to allow arch to examine PT_*PROC headers
   - Support for new style FPU register model in O32
   - VDSO randomization.
   - BCM47xx cleanups
   - BCM47xx reimplement the way the kernel accesses NVRAM information.
   - Random cleanups
   - Add support for ATH25 platforms
   - Remove pointless locking code in some PCI platforms.
   - Some improvments to EVA support
   - Minor Alchemy cleanup"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (185 commits)
  MIPS: Add MFHC0 and MTHC0 instructions to uasm.
  MIPS: Cosmetic cleanups of page table headers.
  MIPS: Add CP0 macros for extended EntryLo registers
  MIPS: Remove now unused definition of phys_t.
  MIPS: Replace use of phys_t with phys_addr_t.
  MIPS: Replace MIPS-specific 64BIT_PHYS_ADDR with generic PHYS_ADDR_T_64BIT
  PCMCIA: Alchemy Don't select 64BIT_PHYS_ADDR in Kconfig.
  MIPS: lib: memset: Clean up some MIPS{EL,EB} ifdefery
  MIPS: iomap: Use __mem_{read,write}{b,w,l} for MMIO
  MIPS: <asm/types.h> fix indentation.
  MAINTAINERS: Add entry for BMIPS multiplatform kernel
  MIPS: Enable VDSO randomization
  MIPS: Remove a temporary hack for debugging cache flushes in SMTC configuration
  MIPS: Remove declaration of obsolete arch_init_clk_ops()
  MIPS: atomic.h: Reformat to fit in 79 columns
  MIPS: Apply `.insn' to fixup labels throughout
  MIPS: Fix microMIPS LL/SC immediate offsets
  MIPS: Kconfig: Only allow 32-bit microMIPS builds
  MIPS: signal.c: Fix an invalid cast in ISA mode bit handling
  MIPS: mm: Only build one microassembler that is suitable
  ...
2014-12-11 17:56:37 -08:00
Ralf Baechle 15d45cce3a MIPS: Replace use of phys_t with phys_addr_t.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 22:47:31 +01:00
Prem Karat ccd3988086 MIPS: Enable VDSO randomization
Based on commit 1091458d09 (mmap randomization)

For 32-bit address spaces randomize within a
16MB space, for 64-bit within a 256MB space.

Test Results:
------------
Without Patch (VDSO is not randomized)
---------------------------------------
root@Maleo:~# ./aslr vdso
FAIL: ASLR not functional (vdso always at 0x7fff7000)

root@Maleo:~# ./aslr rekey vdso
pre_val==cur_val
value=0x7fff7000

With patch:(VDSO is randmoized and doesn't interfere with stack)
----------------------------------------------------------------
root@cavium-octeon2:~# ./aslr rekey vdso
pre_val!=cur_val
previous_value=0x7f830ea2
current_value=0x776e2000
root@cavium-octeon2:~# ./aslr rekey vdso
pre_val!=cur_val
previous_value=0x7fb0cea2
current_value=0x77209000
root@cavium-octeon2:~# ./aslr rekey vdso
pre_val!=cur_val
previous_value=0x7f985ea2
current_value=0x7770c000
root@cavium-octeon2:~# ./aslr rekey vdso
pre_val!=cur_val
previous_value=0x7fbc6ea2
current_value=0x7fe25000

Maps file output:
-------------------------
root@cavium-octeon2:~# ./aslr rekey maps
78584000-785a5000 rwxp 00000000 00:00 0                                  [heap]
7f9d0000-7f9f1000 rw-p 00000000 00:00 0                                  [stack]
7ffa5000-7ffa6000 r-xp 00000000 00:00 0                                  [vdso]

root@cavium-octeon2:~# ./aslr rekey maps
77de0000-77e01000 rwxp 00000000 00:00 0                                  [heap]
7f91b000-7f93c000 rw-p 00000000 00:00 0                                  [stack]
7ff99000-7ff9a000 r-xp 00000000 00:00 0                                  [vdso]

root@cavium-octeon2:~# ./aslr rekey maps
77d7f000-77da0000 rwxp 00000000 00:00 0                                  [heap]
7fc2a000-7fc4b000 rw-p 00000000 00:00 0                                  [stack]
7fe09000-7fe0a000 r-xp 00000000 00:00 0                                  [vdso]

root@cavium-octeon2:~# ./aslr rekey maps
7794c000-7794d000 r-xp 00000000 00:00 0                                  [vdso]
77e4b000-77e6c000 rwxp 00000000 00:00 0                                  [heap]
7f6e7000-7f708000 rw-p 00000000 00:00 0                                  [stack]
root@cavium-octeon2:~#

Signed-off-by: Prem Karat <pkarat@mvista.com>
Cc: linux-mips@linux-mips.org
Cc: sergei.shtylyov@cogentembedded.com
Cc: ddaney.cavm@gmail.com
Patchwork: https://patchwork.linux-mips.org/patch/6812
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:38 +01:00
Maciej W. Rozycki 0e525e48f7 MIPS: Apply `.insn' to fixup labels throughout
Fix the issue with the ISA bit being lost in fixups that jump to labels
placed just before a section switch.  Such a switch leads to the ISA bit
being lost, because GAS concludes there is no code that follows and
therefore the label refers to data.  Use the `.insn' pseudo-op to
convince the tool this is not the case.

This lack of label annotation leads to microMIPS compilation errors
like:

mips-linux-gnu-ld: arch/mips/built-in.o: .fixup+0x3b8: Unsupported jump between ISA modes; consider recompiling with interlinking enabled.
mips-linux-gnu-ld: final link failed: Bad value

Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8483/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:36 +01:00
Maciej W. Rozycki 2fabc7d25d MIPS: signal.c: Fix an invalid cast in ISA mode bit handling
Fix:

arch/mips/kernel/signal.c: In function 'handle_signal':
arch/mips/kernel/signal.c:533:21: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
  unsigned int tmp = (unsigned int)current->mm->context.vdso;
                     ^
arch/mips/kernel/signal.c:536:9: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
  vdso = (void *)tmp;
         ^
cc1: all warnings being treated as errors

when building a 64-bit kernel.

This is not really a supported configuration, but the cast is wrong
either way, Linux makes the assumption that sizeof(void *) equals
sizeof(unsigned long) and therefore the latter type is expected to be
used where integer operations have to be applied to pointers for some
reason.

Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8480/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:36 +01:00
Markos Chandras 26b40ef1aa MIPS: traps: Dump the PageGrain and Wired registers on MC
They can be useful to determine how the MMU is configured on a MC
exception.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8401/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:31 +01:00
Markos Chandras 31ec86b854 MIPS: traps: Dump the HTW registers on a MC exception
The HTW registers can be useful to debug a MC exception.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8400/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:31 +01:00
Markos Chandras 314727fe5c MIPS: traps: Replace printk with pr_err for MC exceptions
printk should not be used without a KERN_ facility level

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8399/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:30 +01:00
Andrew Bresticker a331ce63c8 clocksource: mips-gic: Combine with GIC clockevent driver
Combine the GIC clocksource driver with the GIC clockevent driver from
arch/mips/kernel/cevt-gic.c and remove the clockevent driver's separate
Kconfig symbol.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8132/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:15 +01:00
Andrew Bresticker fa5635a277 MIPS: Move GIC clocksource driver to drivers/clocksource/
Move the GIC clocksource driver to drivers/clocksource/mips-gic-timer.c.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8133/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:14 +01:00
Kevin Cernekee 84988c0681 MIPS: Create a helper function for DT setup
A couple of platforms register two buses and call of_platform_populate().
Move this into a common function to reduce duplication.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: f.fainelli@gmail.com
Cc: mbizon@freebox.fr
Cc: jogo@openwrt.org
Cc: jfraser@broadcom.com
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8167/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:12 +01:00
Kevin Cernekee 68e6a78373 MIPS: BMIPS: Add PRId for BMIPS5200 (Whirlwind)
This is a dual core (quad thread) BMIPS5000.  It needs a little extra
code to boot the second core (CPU2/CPU3), but for now we can treat it the
same as a single core BMIPS5000.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: f.fainelli@gmail.com
Cc: mbizon@freebox.fr
Cc: jogo@openwrt.org
Cc: jfraser@broadcom.com
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8166/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:12 +01:00
Kevin Cernekee d8010ceba6 MIPS: BMIPS: Let each platform customize the CPU1 IRQ mask
On some chips like bcm3384, "other stuff" gets wired up to CPU1's IE_IRQ1
input, generating spurious IRQs.  In this case we want the platform code
to be able to mask it off.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: f.fainelli@gmail.com
Cc: mbizon@freebox.fr
Cc: jogo@openwrt.org
Cc: jfraser@broadcom.com
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8163/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:11 +01:00
Kevin Cernekee 3677a28362 MIPS: BMIPS: Explicitly configure reset vectors prior to secondary boot
The secondary CPU's reset vector needs to be set to KSEG1 for a cold
boot (release from reset), or KSEG0 for a warm restart.  On a cold boot
KSEG0 may be unavailable (BMIPS4380), and on a warm restart KSEG1 may
be unavailable (XKS01 mode on 4380 or 5000).

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: f.fainelli@gmail.com
Cc: mbizon@freebox.fr
Cc: jogo@openwrt.org
Cc: jfraser@broadcom.com
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8161/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:10 +01:00
Jon Fraser 230b6ff575 MIPS: BMIPS: Mask off timer IRQs when hot-unplugging a CPU
CPU interrupts need to be disabled on a cpu being taken down.
When a cpu is hot-plugged out of the system the following sequence occurs.

On the CPU where the hotplug sequence was initiated:
    cpu_down
        _cpu_down {
            __cpu_notify(CPU_DOWN_PREPARE
            __stop_machine(take_cpu_down
                wait for cpu to run disable code.
            __cpu_die
        }

On the CPU  being disabled:
    take_cpu_down
        __cpu_disable {
            mp_ops->cpu_disable
                bmips_cpu_disable
                    clear_c0_status(IE_IRQ5) (added)
            cpu_notify(CPU_DYING...
        }

Before the cpu_notifier is called with CPU_DYING, all interrupts on the
dying cpu must be disabled.  This guarantees that before tick_notify is
called with the CPU_DYING event and sets the clock device pointer to
NULL, there can not be any more clock interrupts.

When this wasn't done, an unfortunately-timed timer interrupt sometimes
caused hangs immediately prior to system suspend:

    Debug PM is not enabled. To enable partial suspend, rebuild kernel with CONFIG_PM_DEBUG
    Pass 1 out of 1,PM: Syncing filesystems ... mode=none, tp1=done.
    1, flags=5, cycle_tp=, sleep=
    Freezing user space processes ... (elapsed 0.01 seconds) done.
    Freezing remaining freezable tasks ... (elapsed 0.01 seconds) done.
    PM: suspend of devices complete after 54.199 msecs
    PM: late suspend of devices complete after 0.172 msecs
    Disabling non-boot CPUs ...
    SMP: CPU1 is offline
    INFO: rcu_sched detected stalls on CPUs/tasks: { 3} (detected by 0, t=62537 jiffies)
    Call Trace:
    [<804baa78>] dump_stack+0x8/0x34
    [<8008a2d8>] __rcu_pending+0x4b8/0x55c
    [<8008adf4>] rcu_check_callbacks+0x78/0x180
    [<80037830>] update_process_times+0x40/0x6c
    [<80072fe4>] tick_sched_timer+0x74/0xe4
    [<80050180>] __run_hrtimer.clone.30+0x64/0x140
    [<80051150>] hrtimer_interrupt+0x19c/0x4bc
    [<8000cdb8>] c0_compare_interrupt+0x50/0x88
    [<80081b18>] handle_irq_event_percpu+0x5c/0x2f4
    [<80086490>] handle_percpu_irq+0x8c/0xc0
    [<800811b4>] generic_handle_irq+0x34/0x54
    [<800067dc>] do_IRQ+0x18/0x2c
    [<8000375c>] plat_irq_dispatch+0xd0/0x128
    [<80004a04>] ret_from_irq+0x0/0x4
    [<80004c40>] r4k_wait+0x20/0x40
    [<80006b6c>] cpu_idle+0x98/0xf0
    [<805d3988>] start_kernel+0x424/0x440

Signed-off-by: Jon Fraser <jfraser@broadcom.com>
Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: f.fainelli@gmail.com
Cc: mbizon@freebox.fr
Cc: jogo@openwrt.org
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8160/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:10 +01:00
Jon Fraser fa01067259 MIPS: BMIPS: Allow BMIPS3300 to utilize SMP ebase relocation code
BMIPS3300 processors do not have the hardware to support SMP, but with a
small tweak, the SMP ebase relocation code allows BMIPS3300-based
platforms to reuse the S2/S3 power management code from BMIPS4380-based
chips.  Normally this is as simple as adding one line to prom_init():

    board_ebase_setup = &bmips_ebase_setup;

Signed-off-by: Jon Fraser <jfraser@broadcom.com>
Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: f.fainelli@gmail.com
Cc: mbizon@freebox.fr
Cc: jogo@openwrt.org
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8159/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:10 +01:00
Kevin Cernekee fc45578793 MIPS: BMIPS: Introduce helper function to change the reset vector
This will need to be called from a few different places, and the logic
is starting to get a bit hairy (with the need for IPIs, CPU bug
workarounds, and hazards).

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: f.fainelli@gmail.com
Cc: mbizon@freebox.fr
Cc: jogo@openwrt.org
Cc: jfraser@broadcom.com
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8158/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:10 +01:00
Kevin Cernekee bdb2e05c90 MIPS: BMIPS: Align secondary boot sequence with latest firmware releases
On some older BMIPS5200 (dual core / quad thread) platforms, the
PROM code set up CPU2/CPU3 so they would be started through an NMI
instead of through the ACTION register.  But this was incompatible with
some power management features that were later added, so the scheme was
changed so that Linux is fully responsible for booting CPU2/CPU3.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: f.fainelli@gmail.com
Cc: mbizon@freebox.fr
Cc: jogo@openwrt.org
Cc: jfraser@broadcom.com
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8157/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:10 +01:00
Paul Burton f4af6fb2fc MIPS: Kconfig option to better exercise/debug hybrid FPRs
The hybrid FPR scheme exists to allow for compatibility between existing
FP32 code and newly compiled FP64A code. Such code should hopefully be
rare in the real world, and for the moment is difficult to come across.
All code except that built for the FP64 ABI can correctly execute using
the hybrid FPR scheme, so debugging the hybrid FPR implementation can
be eased by forcing all such code to use it. This is undesirable in
general due to the trap & emulate overhead of the hybrid FPR
implementation, but is a very useful option to have for debugging.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7680/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:08 +01:00
Paul Burton 90cee759f0 MIPS: ELF: Set FP mode according to .MIPS.abiflags
This patch reads the .MIPS.abiflags section when it is present, and sets
the FP mode of the task accordingly. Any loaded ELF files which do not
contain a .MIPS.abiflags section will continue to observe the previous
behaviour, that is FR=1 if EF_MIPS_FP64 is set else FR=0.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7681/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:07 +01:00
Paul Burton 4227a2d4ef MIPS: Support for hybrid FPRs
Hybrid FPRs is a scheme where scalar FP registers are 64b wide, but
accesses to odd indexed single registers use bits 63:32 of the
preceeding even indexed 64b register. In this mode all FP code
except that built for the plain FP64 ABI can execute correctly. Most
notably a combination of FP64A & FP32 code can execute correctly,
allowing for existing FP32 binaries to be linked with new FP64A binaries
that can make use of 64 bit FP & MSA.

Hybrid FPRs are implemented by setting both the FR & FRE bits, trapping
& emulating single precision FP instructions (via Reserved Instruction
exceptions) whilst allowing others to execute natively. It therefore has
a penalty in terms of execution speed, and should only be used when no
fully native mode can be. As more binaries are recompiled to use either
the FPXX or FP64(A) ABIs, the need for hybrid FPRs should diminish.
However in the short to mid term it allows for a gradual transition
towards that world, rather than a complete ABI break which is not
feasible for some users & not desirable for many.

A task will be executed using the hybrid FPR scheme when its
TIF_HYBRID_FPREGS flag is set & TIF_32BIT_FPREGS is clear. A further
patch will set the flags as necessary, this patch simply adds the
infrastructure necessary for the hybrid FPR mode to work.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7683/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:07 +01:00
Paul Burton d175ed2bd6 MIPS: Ensure Config5.UFE is clear on boot
As is done for UFR, ensure that userland cannot directly manipulate the
mode by clearing the UFE bit during boot.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7677/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:07 +01:00
Paul Burton adac5d535d MIPS: detect presence of the FRE & UFR bits
Detect the presence of the Config5 FRE & UFE bits, as indicated by the
FREP bit in FPIR. Record this as a CPU option bit, and provide a
cpu_has_fre macro to ease checking of that option bit.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7678/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:06 +01:00
Ralf Baechle 4ff3fccd86 MIPS: Remove __strlen_user().
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:00 +01:00
Andrew Bresticker 4060bbe993 MIPS: Move gic.h to include/linux/irqchip/mips-gic.h
Now that the MIPS GIC irqchip lives in drivers/irqchip/, move
its header over to include/linux/irqchip/.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8129/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:59 +01:00
Andrew Bresticker 387904ff84 irqchip: mips-gic: Export function to read counter width
Export the function gic_get_count_width to read the width of
the GIC global counter from GIC_SH_CONFIG.  Update the GIC
clocksource driver to use this new function.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8124/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:57 +01:00
Andrew Bresticker e9de688dac irqchip: mips-gic: Support local interrupts
The MIPS GIC supports 7 local interrupts, 2 of which are the GIC
local watchdog and count/compare timer.  The remainder are CPU
interrupts which may optionally be re-routed through the GIC.
GIC hardware IRQs 0-6 are now used for local interrupts while
hardware IRQs 7+ are used for external (shared) interrupts.

Note that the 5 CPU interrupts may not be re-routable through
the GIC.  In that case mapping will fail and the vectors reported
in C0_IntCtl should be used instead.  gic_get_c0_compare_int() and
gic_get_c0_perfcount_int() will return the correct IRQ number to
use for the C0 timer and perfcounter interrupts based on the
routability of those interrupts through the GIC.

A separate irq_chip, with callbacks that mask/unmask the local
interrupt on all CPUs, is used for the C0 timer and performance
counter interrupts since all other platforms do not use the percpu
IRQ API for those interrupts.

Malta, SEAD-3, and the GIC clockevent driver have been updated
to use local interrupts and the R4K clockevent driver has been
updated to poll for C0 timer interrupts through the GIC when
the GIC is present.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7819/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:56 +01:00
Andrew Bresticker 18743d2781 irqchip: mips-gic: Stop using per-platform mapping tables
Now that the GIC properly uses IRQ domains, kill off the per-platform
routing tables that were used to make the GIC appear transparent.

This includes:
 - removing the mapping tables and the support for applying them,
 - moving GIC IPI support to the GIC driver,
 - properly routing the i8259 through the GIC on Malta, and
 - updating IRQ assignments on SEAD-3 when the GIC is present.

Platforms no longer will pass an interrupt mapping table to gic_init.
Instead, they will pass the CPU interrupt vector (2 - 7) that they
expect the GIC to route interrupts to.  Note that in EIC mode this
value is ignored and all GIC interrupts are routed to EIC vector 1.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7816/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:56 +01:00
Andrew Bresticker 8a19b8f194 MIPS: Move GIC to drivers/irqchip/
Move GIC irqchip support to drivers/irqchip/ and rename the Kconfig
option from IRQ_GIC to MIPS_GIC to avoid confusion with the ARM GIC.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7812/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:54 +01:00
Andrew Bresticker ff1e29ade4 MIPS: smp-cps: Enable all hardware interrupts on secondary CPUs
Currently interrupt vectors 2 and 5 are left disabled on secondary CPUs.
Since systems using CPS must also have a GIC, which is responsible for
routing all external interrupts and can map them to any hardware interrupt
vector, enable the remaining vectors.  The two software interrupt vectors
are left disabled since they are not used with CPS.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7803/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:53 +01:00
Andrew Bresticker a669efc4a3 MIPS: Add hook to get C0 performance counter interrupt
The hardware perf event driver and oprofile interpret the global
cp0_perfcount_irq differently: in the hardware perf event driver
it is an offset from MIPS_CPU_IRQ_BASE and in oprofile it is the
actual IRQ number.  This still works most of the time since
MIPS_CPU_IRQ_BASE is usually 0, but is clearly wrong.  Since the
performance counter interrupt may vary from platform to platform
like the C0 timer interrupt, add the optional get_c0_perfcount_int
hook which returns the IRQ number of the performance counter.
The hook should return < 0 if the performance counter interrupt is
shared with the timer.  If the hook is not present, the CPU vector
reported in C0_IntCtl (cp0_perfcount_irq) is used.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7805/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:53 +01:00
Andrew Bresticker 079a460176 MIPS: i8259: Use IRQ domains
Create a legacy IRQ domain for the 16 i8259 interrupts.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7804/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:52 +01:00
Andrew Bresticker f64e55dcbf MIPS: Set vint handler when mapping CPU interrupts
When mapping an interrupt in the CPU IRQ domain, set the vint handler
for that interrupt if the CPU uses vectored interrupt handling.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7802/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:52 +01:00
Andrew Bresticker 85f7cdacbb MIPS: Provide a generic plat_irq_dispatch
For platforms which boot with device-tree or have correctly chained
all external interrupt controllers, a generic plat_irq_dispatch() can
be used.  Implement a plat_irq_dispatch() which simply handles all the
pending interrupts as reported by C0_Cause.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7801/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:52 +01:00
Andrew Bresticker afe8dc2547 MIPS: Rename mips_cpu_intc_init() -> mips_cpu_irq_of_init()
mips_cpu_intc_init() is used for DT-based initialization of the CPU
IRQ domain.  Give it a more appropriate name.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7800/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:52 +01:00
Andrew Bresticker 0f84c30535 MIPS: Always use IRQ domains for CPU IRQs
Use an IRQ domain for the 8 CPU IRQs in both the DT and non-DT cases.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7799/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:51 +01:00
Markos Chandras 97f4ad29da MIPS: cpu: Add 'noftlb' kernel command line option to disable the FTLB
Add new 'noftlb' kernel command line option to disable the FTLB.
Since the kernel command line is not available when probing and
enabling the CPU features in cpu_probe(), we let the kernel configure
the FTLB during the config4 decode operation and we disable the FTLB later
on, once the command line has become available to us. This should have
no negative effects since FTLB isn't used so early in the boot process.
FTLB increases the effective TLB size leading to less TLB misses. However,
sometimes it's useful to be able to disable it when debugging memory related
core features or other hardware components.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/7586/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:51 +01:00
Joe Perches 7178d2cdd9 mips: Convert pr_warning to pr_warn
Use the much more common pr_warn instead of pr_warning
with the goal of removing pr_warning eventually.

Other miscellanea:

o Coalesce formats
o Realign arguments

Signed-off-by: Joe Perches <joe@perches.com>
Cc: linux-mips <linux-mips@linux-mips.org>
Cc: LKML <linux-kernel@vger.kernel.org>
Patchwork: https://patchwork.linux-mips.org/patch/7935/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:51 +01:00
Eunbong Song 856839b768 MIPS: Add arch_trigger_all_cpu_backtrace() function
Currently, arch_trigger_all_cpu_backtrace() is defined in only x86 and
sparc which have an NMI.  But in case of softlockup, it could be possible
to dump backtrace of all cpus. and this could be helpful for debugging.

for example, if system has 2 cpus.

	CPU 0				CPU 1
 acquire read_lock()

				try to do write_lock()

 ,,,
 missing read_unlock()

In this case, softlockup will occur becasuse CPU 0 does not call
read_unlock().  And dump_stack() print only backtrace for "CPU 0". If
CPU1's backtrace is printed it's very helpful.

[ralf@linux-mips.org: Fixed whitespace and formatting issues.]

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8200/
2014-11-24 07:44:49 +01:00
Ralf Baechle 635c990706 MIPS: Remove useless parentheses
Based on the spatch

@@
expression e;
@@
- return (e);
+ return e;

with heavy hand editing because some of the changes are either whitespace
or identation only or result in excessivly long lines.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:49 +01:00
Steven J. Hill b4da18b371 MIPS: Fix address type used for early memory detection.
In 'early_parse_mem' the data type used for the start
and size of a memory region specified on the command line
is incorrect. If 64-bit addressing is used, the value
gets truncated.

Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8456/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:07 +01:00
Markos Chandras 76cff82943 MIPS: kernel: cps-vec: Set ISA level to mips32r2 for the MIPS MT ASE
Fixes the following build warnings:
arch/mips/kernel/cps-vec.S: Assembler messages:
arch/mips/kernel/cps-vec.S:228: Warning: the `mt' extension requires
MIPS32 revision 2 or greater
[...]
arch/mips/kernel/cps-vec.S: Assembler messages:
arch/mips/kernel/cps-vec.S:345: Warning: the `mt' extension requires
MIPS32 revision 2 or greater

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <Paul.Burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7355/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:06 +01:00
Paul Burton 14fa12df1d MIPS: fix EVA & non-SMP non-FPU FP context signal handling
The save_fp_context & restore_fp_context pointers were being assigned
to the wrong variables if either:

  - The kernel is configured for UP & runs on a system without an FPU,
    since b2ead52828 "MIPS: Move & rename
    fpu_emulator_{save,restore}_context".

  - The kernel is configured for EVA, since ca750649e0 "MIPS: kernel:
    signal: Prevent save/restore FPU context in user memory".

This would lead to FP context being clobbered incorrectly when setting
up a sigcontext, then the garbage values being saved uselessly when
returning from the signal.

Fix by swapping the pointer assignments appropriately.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: stable@vger.kernel.org # v3.15+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8230/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:06 +01:00
Markos Chandras cf0a8aa022 MIPS: cpu-probe: Set the FTLB probability bit on supported cores
Make use of the Config6/FLTBP bit to set the probability of a TLBWR
instruction to hit the FTLB or the VTLB. A value of 0 (which may be
the default value on certain cores, such as proAptiv or P5600)
means that a TLBWR instruction will never hit the VTLB which
leads to performance limitations since it effectively decreases
the number of available TLB slots.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: <stable@vger.kernel.org> # v3.15+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8368/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:05 +01:00
Kevin Cernekee 4ec8f9e9b0 MIPS: BMIPS: Fix ".previous without corresponding .section" warnings
Commit 078a55fc82 ("Delete __cpuinit/__CPUINIT usage from MIPS code")
removed our __CPUINIT directives, so now the ".previous" directives
are superfluous.  Remove them.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: f.fainelli@gmail.com
Cc: mbizon@freebox.fr
Cc: jogo@openwrt.org
Cc: jfraser@broadcom.com
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8156/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:05 +01:00
Rafał Miłecki 7f0dd7683c MIPS: Fix info about plat_setup in arch_mem_init comment
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7607/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:04 +01:00
Masanari Iida 3dc4bf310a MIPS: rtlx: Remove KERN_DEBUG from pr_debug() arguments in rtlx.c
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7938/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:44:04 +01:00
Maciej W. Rozycki 935c2dbec4 MIPS: jump_label.c: Handle the microMIPS J instruction encoding
Implement the microMIPS encoding of the J instruction for the purpose of
the static keys feature, fixing a crash early on in bootstrap as the
kernel is unhappy seeing the ISA bit set in jump table entries.  Make
sure the ISA bit correctly reflects the instruction encoding chosen for
the kernel, 0 for the standard MIPS and 1 for the microMIPS encoding.

Also make sure the instruction to patch is a 32-bit NOP in the microMIPS
mode as by default the 16-bit short encoding is assumed

Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8516/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-19 18:22:09 +01:00
Maciej W. Rozycki 99436f7d69 MIPS: jump_label.c: Correct the span of the J instruction
Correct the check for the span of the 256MB segment addressable by the J
instruction according to this instruction's semantics.  The calculation
of the jump target is applied to the address of the delay-slot
instruction that immediately follows.  Adjust the check accordingly by
adding 4 to `e->code' that holds the address of the J instruction
itself.

Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8515/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-19 18:22:08 +01:00
Huacai Chen 7352c8b13d MIPS: Loongson: Set Loongson-3's ISA level to MIPS64R1
In CPU manual Loongson-3 is MIPS64R2 compatible, but during tests we
found that its EI/DI instructions have problems. So we just set the ISA
level to MIPS64R1.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/8320/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-19 18:22:07 +01:00
Huacai Chen cc94ea3115 MIPS: Loongson: Fix the write-combine CCA value setting
All Loongson-2/3 processors support _CACHE_UNCACHED_ACCELERATED, not
only Loongson-3A.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/8319/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-19 18:22:07 +01:00
Manuel Lauss 842dfc11ea MIPS: Fix build with binutils 2.24.51+
Starting with version 2.24.51.20140728 MIPS binutils complain loudly
about mixing soft-float and hard-float object files, leading to this
build failure since GCC is invoked with "-msoft-float" on MIPS:

{standard input}: Warning: .gnu_attribute 4,3 requires `softfloat'
  LD      arch/mips/alchemy/common/built-in.o
mipsel-softfloat-linux-gnu-ld: Warning: arch/mips/alchemy/common/built-in.o
 uses -msoft-float (set by arch/mips/alchemy/common/prom.o),
 arch/mips/alchemy/common/sleeper.o uses -mhard-float

To fix this, we detect if GAS is new enough to support "-msoft-float" command
option, and if it does, we can let GCC pass it to GAS;  but then we also need
to sprinkle the files which make use of floating point registers with the
necessary ".set hardfloat" directives.

Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com>
Cc: Linux-MIPS <linux-mips@linux-mips.org>
Cc: Matthew Fortune <Matthew.Fortune@imgtec.com>
Cc: Markos Chandras <Markos.Chandras@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/8355/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-07 15:07:36 +01:00
Zubair Lutfullah Kakakhel 30fa0530ff MIPS: CMA: Do not reserve memory if not required
Even if CMA is disabled, the for_each_memblock macro expands
to run reserve_bootmem once. Hence, reserve_bootmem attempts to
reserve location 0 of size 0.

Add a check to avoid that.

Issue was highlighted during testing with EVA enabled.
resrve_bootmem used to exit gracefully when passed arguments to
reserve 0 size location at 0 without EVA.

But with EVA enabled, macros would point to different addresses
and the code would trigger a BUG.

Signed-off-by: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Tested-by: Markos Chandras <markos.chandras@imgtec.com>
Tested-by: Huacai Chen <chenhc@lemote.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8231/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-10-29 02:59:25 +01:00
Ralf Baechle 5df4c8dbbc MIPS: Wire up bpf syscall.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-10-27 03:37:42 +01:00
Markos Chandras 9d26024c96 MIPS: idle: Remove leftover __pastwait symbol and its references
The __pastwait symbol was only used by the address_is_in_r4k_wait_irqoff
function but this is no longer used since the SMTC removal in commit
b633648c5a ('MIPS: MT: Remove SMTC support'). That symbol also led to
build failures under certain random configuration due to the way the
compiler compiled the r4k_wait_irqoff function. If that function was
called multiple times, the __pastwait symbol was redefined breaking the
build like this:

CHK     include/generated/compile.h
CC      arch/mips/kernel/idle.o
{standard input}: Assembler messages:
{standard input}:527: Error: symbol `__pastwait' is already defined

Link: http://www.linux-mips.org/cgi-bin/mesg.cgi?a=linux-mips&i=1244879922.24479.30.camel%40falcon
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/7791/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-10-23 19:24:05 +02:00
Linus Torvalds ab074ade9c Merge git://git.infradead.org/users/eparis/audit
Pull audit updates from Eric Paris:
 "So this change across a whole bunch of arches really solves one basic
  problem.  We want to audit when seccomp is killing a process.  seccomp
  hooks in before the audit syscall entry code.  audit_syscall_entry
  took as an argument the arch of the given syscall.  Since the arch is
  part of what makes a syscall number meaningful it's an important part
  of the record, but it isn't available when seccomp shoots the
  syscall...

  For most arch's we have a better way to get the arch (syscall_get_arch)
  So the solution was two fold: Implement syscall_get_arch() everywhere
  there is audit which didn't have it.  Use syscall_get_arch() in the
  seccomp audit code.  Having syscall_get_arch() everywhere meant it was
  a useless flag on the stack and we could get rid of it for the typical
  syscall entry.

  The other changes inside the audit system aren't grand, fixed some
  records that had invalid spaces.  Better locking around the task comm
  field.  Removing some dead functions and structs.  Make some things
  static.  Really minor stuff"

* git://git.infradead.org/users/eparis/audit: (31 commits)
  audit: rename audit_log_remove_rule to disambiguate for trees
  audit: cull redundancy in audit_rule_change
  audit: WARN if audit_rule_change called illegally
  audit: put rule existence check in canonical order
  next: openrisc: Fix build
  audit: get comm using lock to avoid race in string printing
  audit: remove open_arg() function that is never used
  audit: correct AUDIT_GET_FEATURE return message type
  audit: set nlmsg_len for multicast messages.
  audit: use union for audit_field values since they are mutually exclusive
  audit: invalid op= values for rules
  audit: use atomic_t to simplify audit_serial()
  kernel/audit.c: use ARRAY_SIZE instead of sizeof/sizeof[0]
  audit: reduce scope of audit_log_fcaps
  audit: reduce scope of audit_net_id
  audit: arm64: Remove the audit arch argument to audit_syscall_entry
  arm64: audit: Add audit hook in syscall_trace_enter/exit()
  audit: x86: drop arch from __audit_syscall_entry() interface
  sparc: implement is_32bit_task
  sparc: properly conditionalize use of TIF_32BIT
  ...
2014-10-19 16:25:56 -07:00
Linus Torvalds 857b50f5d0 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS updates from Ralf Baechle:
 "This is the MIPS pull request for the next kernel:

   - Zubair's patch series adds CMA support for MIPS.  Doing so it also
     touches ARM64 and x86.
   - remove the last instance of IRQF_DISABLED from arch/mips
   - updates to two of the MIPS defconfig files.
   - cleanup of how cache coherency bits are handled on MIPS and
     implement support for write-combining.
   - platform upgrades for Alchemy
   - move MIPS DTS files to arch/mips/boot/dts/"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (24 commits)
  MIPS: ralink: remove deprecated IRQF_DISABLED
  MIPS: pgtable.h: Implement the pgprot_writecombine function for MIPS
  MIPS: cpu-probe: Set the write-combine CCA value on per core basis
  MIPS: pgtable-bits: Define the CCA bit for WC writes on Ingenic cores
  MIPS: pgtable-bits: Move the CCA bits out of the core's ifdef blocks
  MIPS: DMA: Add cma support
  x86: use generic dma-contiguous.h
  arm64: use generic dma-contiguous.h
  asm-generic: Add dma-contiguous.h
  MIPS: BPF: Add new emit_long_instr macro
  MIPS: ralink: Move device-trees to arch/mips/boot/dts/
  MIPS: Netlogic: Move device-trees to arch/mips/boot/dts/
  MIPS: sead3: Move device-trees to arch/mips/boot/dts/
  MIPS: Lantiq: Move device-trees to arch/mips/boot/dts/
  MIPS: Octeon: Move device-trees to arch/mips/boot/dts/
  MIPS: Add support for building device-tree binaries
  MIPS: Create common infrastructure for building built-in device-trees
  MIPS: SEAD3: Enable DEVTMPFS
  MIPS: SEAD3: Regenerate defconfigs
  MIPS: Alchemy: DB1300: Add touch penirq support
  ...
2014-10-18 14:24:36 -07:00
Linus Torvalds 0429fbc0bd Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
Pull percpu consistent-ops changes from Tejun Heo:
 "Way back, before the current percpu allocator was implemented, static
  and dynamic percpu memory areas were allocated and handled separately
  and had their own accessors.  The distinction has been gone for many
  years now; however, the now duplicate two sets of accessors remained
  with the pointer based ones - this_cpu_*() - evolving various other
  operations over time.  During the process, we also accumulated other
  inconsistent operations.

  This pull request contains Christoph's patches to clean up the
  duplicate accessor situation.  __get_cpu_var() uses are replaced with
  with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr().

  Unfortunately, the former sometimes is tricky thanks to C being a bit
  messy with the distinction between lvalues and pointers, which led to
  a rather ugly solution for cpumask_var_t involving the introduction of
  this_cpu_cpumask_var_ptr().

  This converts most of the uses but not all.  Christoph will follow up
  with the remaining conversions in this merge window and hopefully
  remove the obsolete accessors"

* 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits)
  irqchip: Properly fetch the per cpu offset
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix
  ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write.
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t
  Revert "powerpc: Replace __get_cpu_var uses"
  percpu: Remove __this_cpu_ptr
  clocksource: Replace __this_cpu_ptr with raw_cpu_ptr
  sparc: Replace __get_cpu_var uses
  avr32: Replace __get_cpu_var with __this_cpu_write
  blackfin: Replace __get_cpu_var uses
  tile: Use this_cpu_ptr() for hardware counters
  tile: Replace __get_cpu_var uses
  powerpc: Replace __get_cpu_var uses
  alpha: Replace __get_cpu_var
  ia64: Replace __get_cpu_var uses
  s390: cio driver &__get_cpu_var replacements
  s390: Replace __get_cpu_var uses
  mips: Replace __get_cpu_var uses
  MIPS: Replace __get_cpu_var uses in FPU emulator.
  arm: Replace __this_cpu_ptr with raw_cpu_ptr
  ...
2014-10-15 07:48:18 +02:00
Linus Torvalds ba1a96fc7d Merge branch 'x86-seccomp-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 seccomp changes from Ingo Molnar:
 "This tree includes x86 seccomp filter speedups and related preparatory
  work, which touches core seccomp facilities as well.

  The main idea is to split seccomp into two phases, to be able to enter
  a simple fast path for syscalls with ptrace side effects.

  There's no substantial user-visible (and ABI) effects expected from
  this, except a change in how we emit a better audit record for
  SECCOMP_RET_TRACE events"

* 'x86-seccomp-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86_64, entry: Use split-phase syscall_trace_enter for 64-bit syscalls
  x86_64, entry: Treat regs->ax the same in fastpath and slowpath syscalls
  x86: Split syscall_trace_enter into two phases
  x86, entry: Only call user_exit if TIF_NOHZ
  x86, x32, audit: Fix x32's AUDIT_ARCH wrt audit
  seccomp: Document two-phase seccomp and arch-provided seccomp_data
  seccomp: Allow arch code to provide seccomp_data
  seccomp: Refactor the filter callback and the API
  seccomp,x86,arm,mips,s390: Remove nr parameter from secure_computing
2014-10-14 02:27:06 +02:00
Markos Chandras 8a574cfa26 MIPS: mcount: Adjust stack pointer for static trace in MIPS32
Every mcount() call in the MIPS 32-bit kernel is done as follows:

[...]
move at, ra
jal _mcount
addiu sp, sp, -8
[...]

but upon returning from the mcount() function, the stack pointer
is not adjusted properly. This is explained in details in 58b69401c7
(MIPS: Function tracer: Fix broken function tracing).

Commit ad8c396936 ("MIPS: Unbreak function tracer for 64-bit kernel.)
fixed the stack manipulation for 64-bit but it didn't fix it completely
for MIPS32.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: <stable@vger.kernel.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7792/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-09-26 11:41:17 +02:00
Eric Paris 91397401bb ARCH: AUDIT: audit_syscall_entry() should not require the arch
We have a function where the arch can be queried, syscall_get_arch().
So rather than have every single piece of arch specific code use and/or
duplicate syscall_get_arch(), just have the audit code use the
syscall_get_arch() code.

Based-on-patch-by: Richard Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Cc: linux-alpha@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-ia64@vger.kernel.org
Cc: microblaze-uclinux@itee.uq.edu.au
Cc: linux-mips@linux-mips.org
Cc: linux@lists.openrisc.net
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Cc: user-mode-linux-devel@lists.sourceforge.net
Cc: linux-xtensa@linux-xtensa.org
Cc: x86@kernel.org
2014-09-23 16:21:26 -04:00
Markos Chandras 4f12b91d2d MIPS: cpu-probe: Set the write-combine CCA value on per core basis
Different cores use different CCA values to achieve write-combine
memory writes. For cores that do not support write-combine we
set the default value to CCA:2 (uncached, non-coherent) which is the
default value as set by the kernel.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7402/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-09-22 13:35:53 +02:00
Zubair Lutfullah Kakakhel f46493826a MIPS: DMA: Add cma support
Adds cma support to the MIPS architecture.

cma uses memblock. However, mips uses bootmem.
bootmem is informed about any regions reserved by memblock

dma api is modified to use cma reserved memory regions when available

Tested using cma_test. cma_test is a simple driver that assigns blocks
of memory from cma reserved sections.

Signed-off-by: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Cc: catalin.marinas@arm.com
Cc: will.deacon@arm.com
Cc: tglx@linutronix.de
Cc: mingo@redhat.com
Cc: hpa@zytor.com
Cc: arnd@arndb.de
Cc: gregkh@linuxfoundation.org
Cc: m.szyprowski@samsung.com
Cc: x86@kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-arch@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7360/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-09-22 13:35:52 +02:00
Andy Lutomirski a4412fc948 seccomp,x86,arm,mips,s390: Remove nr parameter from secure_computing
The secure_computing function took a syscall number parameter, but
it only paid any attention to that parameter if seccomp mode 1 was
enabled.  Rather than coming up with a kludge to get the parameter
to work in mode 2, just remove the parameter.

To avoid churn in arches that don't have seccomp filters (and may
not even support syscall_get_nr right now), this leaves the
parameter in secure_computing_strict, which is now a real function.

For ARM, this is a bit ugly due to the fact that ARM conditionally
supports seccomp filters.  Fixing that would probably only be a
couple of lines of code, but it should be coordinated with the audit
maintainers.

This will be a slight slowdown on some arches.  The right fix is to
pass in all of seccomp_data instead of trying to make just the
syscall nr part be fast.

This is a prerequisite for making two-phase seccomp work cleanly.

Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-s390@vger.kernel.org
Cc: x86@kernel.org
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Kees Cook <keescook@chromium.org>
2014-09-03 14:58:17 -07:00
Christoph Lameter 35898716b4 mips: Replace __get_cpu_var uses
__get_cpu_var() is used for multiple purposes in the kernel source. One of
them is address calculation via the form &__get_cpu_var(x).  This calculates
the address for the instance of the percpu variable of the current processor
based on an offset.

Other use cases are for storing and retrieving data from the current
processors percpu area.  __get_cpu_var() can be used as an lvalue when
writing data or on the right side of an assignment.

__get_cpu_var() is defined as :

#define __get_cpu_var(var) (*this_cpu_ptr(&(var)))

__get_cpu_var() always only does an address determination. However, store
and retrieve operations could use a segment prefix (or global register on
other platforms) to avoid the address calculation.

this_cpu_write() and this_cpu_read() can directly take an offset into a
percpu area and use optimized assembly code to read and write per cpu
variables.

This patch converts __get_cpu_var into either an explicit address
calculation using this_cpu_ptr() or into a use of this_cpu operations that
use the offset.  Thereby address calculations are avoided and less registers
are used when code is generated.

At the end of the patch set all uses of __get_cpu_var have been removed so
the macro is removed too.

The patch set includes passes over all arches as well. Once these operations
are used throughout then specialized macros can be defined in non -x86
arches as well in order to optimize per cpu access by f.e.  using a global
register that may be set to the per cpu base.

Transformations done to __get_cpu_var()

1. Determine the address of the percpu instance of the current processor.

	DEFINE_PER_CPU(int, y);
	int *x = &__get_cpu_var(y);

    Converts to

	int *x = this_cpu_ptr(&y);

2. Same as #1 but this time an array structure is involved.

	DEFINE_PER_CPU(int, y[20]);
	int *x = __get_cpu_var(y);

    Converts to

	int *x = this_cpu_ptr(y);

3. Retrieve the content of the current processors instance of a per cpu
variable.

	DEFINE_PER_CPU(int, y);
	int x = __get_cpu_var(y)

   Converts to

	int x = __this_cpu_read(y);

4. Retrieve the content of a percpu struct

	DEFINE_PER_CPU(struct mystruct, y);
	struct mystruct x = __get_cpu_var(y);

   Converts to

	memcpy(&x, this_cpu_ptr(&y), sizeof(x));

5. Assignment to a per cpu variable

	DEFINE_PER_CPU(int, y)
	__get_cpu_var(y) = x;

   Converts to

	__this_cpu_write(y, x);

6. Increment/Decrement etc of a per cpu variable

	DEFINE_PER_CPU(int, y);
	__get_cpu_var(y)++

   Converts to

	__this_cpu_inc(y)

Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-26 13:45:51 -04:00
Ralf Baechle 42944521af MIPS: Wire up new syscalls getrandom and memfd_create.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-26 03:03:40 +02:00
Markos Chandras 56d2960958 MIPS: CPS: Initialize EVA before bringing up VPEs from secondary cores
The CPS code is doing several memory loads when configuring the VPEs
from secondary cores, so the segmentation control registers must be
initialized in time otherwise the kernel will crash with strange
TLB exceptions.

Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: http://patchwork.linux-mips.org/patch/7424/
Signed-off-by: James Hogan <james.hogan@imgtec.com>
2014-08-26 02:18:57 +02:00
Markos Chandras ad61ba23f1 MIPS: scall64-o32: Fix indirect syscall detection
Commit 4c21b8fd8f (MIPS: seccomp: Handle indirect system calls (o32))
added indirect syscall detection for O32 processes running on MIPS64
but it did not work as expected. The reason is the the scall64-o32
implementation differs compared to scall32-o32. In the former, the v0
(syscall number) register contains the absolute syscall number
(4000 + X) whereas in the latter it contains the relative syscall
number (X). Fix the code to avoid doing an extra addition, and load
the v0 register directly to the first argument for syscall_trace_enter.
Moreover, set the .reorder assembler option in order to have better
control on this part of the assembly code.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: http://patchwork.linux-mips.org/patch/7481/
Cc: <stable@vger.kernel.org> # v3.15+
Signed-off-by: James Hogan <james.hogan@imgtec.com>
2014-08-26 02:18:56 +02:00
Yang Wei 014365f583 MIPS: perf: Mark pmu interupt IRQF_NO_THREAD
In RT kernel, I ran into the following calltrace, so PMU interrupts cannot
be threaded

in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/0
INFO: lockdep is turned off.
Call Trace:
[<ffffffff8088595c>] dump_stack+0x1c/0x50
[<ffffffff801a958c>] __might_sleep+0x13c/0x148
[<ffffffff80891c54>] rt_spin_lock+0x3c/0xb0
[<ffffffff801ad29c>] __wake_up+0x3c/0x80
[<ffffffff80243ba4>] perf_event_wakeup+0x8c/0xf8
[<ffffffff80243c50>] perf_pending_event+0x40/0x78
[<ffffffff8023d88c>] irq_work_run+0x74/0xc0
[<ffffffff80152640>] mipsxx_pmu_handle_shared_irq+0x110/0x228
[<ffffffff8015276c>] mipsxx_pmu_handle_irq+0x14/0x30
[<ffffffff801ffda4>] handle_irq_event_percpu+0xbc/0x470
[<ffffffff80204478>] handle_percpu_irq+0x98/0xc8
[<ffffffff801ff284>] generic_handle_irq+0x4c/0x68
[<ffffffff8089748c>] do_IRQ+0x2c/0x48
[<ffffffff80105864>] plat_irq_dispatch+0x64/0xd0

[ralf@linux-mips.org: I don't see why based on this register dump the
handler should be marked IRQF_NO_THREAD - but the handler is manipulating
per-CPU resources so we don't want it to be rescheduled to another CPU.]

Signed-off-by: Yang Wei <Wei.Yang@windriver.com>
Cc: a.p.zijlstra@chello.nl
Cc: paulus@samba.org
Cc: mingo@redhat.com
Cc: acme@kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7506/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-26 02:18:51 +02:00
Yang Wei 91ffaa2783 MIPS: kdump: Set correct value to kexec_indirection_page variable
Since there is not indirection page in crash type, so the vaule of the head
field of kimage structure is not equal to the address of indirection page but
IND_DONE. so we have to set kexec_indirection_page variable to the address of
the head field of image structure.

[ralf@linux-mips.org: Don't add pointless empty line, fix trailing
whitespace damage.]

Signed-off-by: Yang Wei <Wei.Yang@windriver.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7499/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-25 16:33:44 +02:00
Markos Chandras 6521d9a436 MIPS: CPS: Initialize EVA before bringing up VPEs from secondary cores
The CPS code is doing several memory loads when configuring the VPEs
from secondary cores, so the segmentation control registers must be
initialized in time otherwise the kernel will crash with strange
TLB exceptions.

Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: http://patchwork.linux-mips.org/patch/7424/
Signed-off-by: James Hogan <james.hogan@imgtec.com>
2014-08-19 18:24:41 +02:00
Markos Chandras 5245689900 MIPS: scall64-o32: Fix indirect syscall detection
Commit 4c21b8fd8f (MIPS: seccomp: Handle indirect system calls (o32))
added indirect syscall detection for O32 processes running on MIPS64
but it did not work as expected. The reason is the the scall64-o32
implementation differs compared to scall32-o32. In the former, the v0
(syscall number) register contains the absolute syscall number
(4000 + X) whereas in the latter it contains the relative syscall
number (X). Fix the code to avoid doing an extra addition, and load
the v0 register directly to the first argument for syscall_trace_enter.
Moreover, set the .reorder assembler option in order to have better
control on this part of the assembly code.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: http://patchwork.linux-mips.org/patch/7481/
Cc: <stable@vger.kernel.org> # v3.15+
Signed-off-by: James Hogan <james.hogan@imgtec.com>
2014-08-19 18:24:40 +02:00
Yang Wei ec756d45b7 MIPS: perf: Mark pmu interupt IRQF_NO_THREAD
In RT kernel, I ran into the following calltrace, so PMU interrupts cannot
be threaded

in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/0
INFO: lockdep is turned off.
Call Trace:
[<ffffffff8088595c>] dump_stack+0x1c/0x50
[<ffffffff801a958c>] __might_sleep+0x13c/0x148
[<ffffffff80891c54>] rt_spin_lock+0x3c/0xb0
[<ffffffff801ad29c>] __wake_up+0x3c/0x80
[<ffffffff80243ba4>] perf_event_wakeup+0x8c/0xf8
[<ffffffff80243c50>] perf_pending_event+0x40/0x78
[<ffffffff8023d88c>] irq_work_run+0x74/0xc0
[<ffffffff80152640>] mipsxx_pmu_handle_shared_irq+0x110/0x228
[<ffffffff8015276c>] mipsxx_pmu_handle_irq+0x14/0x30
[<ffffffff801ffda4>] handle_irq_event_percpu+0xbc/0x470
[<ffffffff80204478>] handle_percpu_irq+0x98/0xc8
[<ffffffff801ff284>] generic_handle_irq+0x4c/0x68
[<ffffffff8089748c>] do_IRQ+0x2c/0x48
[<ffffffff80105864>] plat_irq_dispatch+0x64/0xd0

[ralf@linux-mips.org: I don't see why based on this register dump the
handler should be marked IRQF_NO_THREAD - but the handler is manipulating
per-CPU resources so we don't want it to be rescheduled to another CPU.]

Signed-off-by: Yang Wei <Wei.Yang@windriver.com>
Cc: a.p.zijlstra@chello.nl
Cc: paulus@samba.org
Cc: mingo@redhat.com
Cc: acme@kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7506/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-18 22:14:39 +02:00
Linus Torvalds 63b12bdb0d Merge branch 'signal-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc
Pull arch signal handling cleanup from Richard Weinberger:
 "This patch series moves all remaining archs to the get_signal(),
  signal_setup_done() and sigsp() functions.

  Currently these archs use open coded variants of the said functions.
  Further, unused parameters get removed from get_signal_to_deliver(),
  tracehook_signal_handler() and signal_delivered().

  At the end of the day we save around 500 lines of code."

* 'signal-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc: (43 commits)
  powerpc: Use sigsp()
  openrisc: Use sigsp()
  mn10300: Use sigsp()
  mips: Use sigsp()
  microblaze: Use sigsp()
  metag: Use sigsp()
  m68k: Use sigsp()
  m32r: Use sigsp()
  hexagon: Use sigsp()
  frv: Use sigsp()
  cris: Use sigsp()
  c6x: Use sigsp()
  blackfin: Use sigsp()
  avr32: Use sigsp()
  arm64: Use sigsp()
  arc: Use sigsp()
  sas_ss_flags: Remove nested ternary if
  Rip out get_signal_to_deliver()
  Clean up signal_delivered()
  tracehook_signal_handler: Remove sig, info, ka and regs
  ...
2014-08-09 09:58:12 -07:00
Linus Torvalds e669830526 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS updates from Ralf Baechle:
 "This is the main pull request for 3.17.  It contains:

   - misc Cavium Octeon, BCM47xx, BCM63xx and Alchemy  updates
   - MIPS ptrace updates and cleanups
   - various fixes that will also go to -stable
   - a number of cleanups and small non-critical fixes.
   - NUMA support for the Loongson 3.
   - more support for MSA
   - support for MAAR
   - various FP enhancements and fixes"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (139 commits)
  MIPS: jz4740: remove unnecessary null test before debugfs_remove
  MIPS: Octeon: remove unnecessary null test before debugfs_remove_recursive
  MIPS: ZBOOT: implement stack protector in compressed boot phase
  MIPS: mipsreg: remove duplicate MIPS_CONF4_FTLBSETS_SHIFT
  MIPS: Bonito64: remove a duplicate define
  MIPS: Malta: initialise MAARs
  MIPS: Initialise MAARs
  MIPS: detect presence of MAARs
  MIPS: define MAAR register accessors & bits
  MIPS: mark MSA experimental
  MIPS: Don't build MSA support unless it can be used
  MIPS: consistently clear MSA flags when starting & copying threads
  MIPS: 16 byte align MSA vector context
  MIPS: disable preemption whilst initialising MSA
  MIPS: ensure MSA gets disabled during boot
  MIPS: fix read_msa_* & write_msa_* functions on non-MSA toolchains
  MIPS: fix MSA context for tasks which don't use FP first
  MIPS: init upper 64b of vector registers when MSA is first used
  MIPS: save/disable MSA in lose_fpu
  MIPS: preserve scalar FP CSR when switching vector context
  ...
2014-08-07 08:47:00 -07:00
Linus Torvalds bb2cbf5e93 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
 "In this release:

   - PKCS#7 parser for the key management subsystem from David Howells
   - appoint Kees Cook as seccomp maintainer
   - bugfixes and general maintenance across the subsystem"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (94 commits)
  X.509: Need to export x509_request_asymmetric_key()
  netlabel: shorter names for the NetLabel catmap funcs/structs
  netlabel: fix the catmap walking functions
  netlabel: fix the horribly broken catmap functions
  netlabel: fix a problem when setting bits below the previously lowest bit
  PKCS#7: X.509 certificate issuer and subject are mandatory fields in the ASN.1
  tpm: simplify code by using %*phN specifier
  tpm: Provide a generic means to override the chip returned timeouts
  tpm: missing tpm_chip_put in tpm_get_random()
  tpm: Properly clean sysfs entries in error path
  tpm: Add missing tpm_do_selftest to ST33 I2C driver
  PKCS#7: Use x509_request_asymmetric_key()
  Revert "selinux: fix the default socket labeling in sock_graft()"
  X.509: x509_request_asymmetric_keys() doesn't need string length arguments
  PKCS#7: fix sparse non static symbol warning
  KEYS: revert encrypted key change
  ima: add support for measuring and appraising firmware
  firmware_class: perform new LSM checks
  security: introduce kernel_fw_from_file hook
  PKCS#7: Missing inclusion of linux/err.h
  ...
2014-08-06 08:06:39 -07:00
Richard Weinberger 7c4f563507 mips: Use sigsp()
Use sigsp() instead of the open coded variant.

Signed-off-by: Richard Weinberger <richard@nod.at>
2014-08-06 13:04:30 +02:00
Richard Weinberger 81d103bf80 mips: Use get_signal() signal_setup_done()
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.

Signed-off-by: Richard Weinberger <richard@nod.at>
2014-08-06 13:03:08 +02:00
Ralf Baechle 475d5928b7 Merge branch '3.16-fixes' into mips-for-linux-next 2014-08-02 00:07:03 +02:00
Paul Burton 1f6c52ff72 MIPS: detect presence of MAARs
Detect the presence of MAAR using the MRP bit in Config5, and record
that presence using a CPU option bit. A cpu_has_maar macro will then
allow code to conditionalise upon the presence of MAARs.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7330/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:45 +02:00
Paul Burton 7daef8f261 MIPS: consistently clear MSA flags when starting & copying threads
The TIF_MSA_CTX_LIVE flag (indicating that a task has MSA context which
needs to be preserved) was being cleared in start_thread, but the
TIF_USEDMSA flag (indicating that a task has used MSA in this timeslice)
was not. In copy_thread neither flag was cleared, but both need to be.
Without clearing these flags the kernel will proceed to attempt to save
MSA context when the task is context switched out, and if the task had
not used MSA in the meantime then it will fail because MSA or the FPU
are disabled. The end result is typically:

  do_cpu invoked from kernel context![#1]:
  CPU: 0 PID: 99 Comm: sh Not tainted 3.16.0-rc4-00025-g6dc9476-dirty #88
  task: 8f23dc60 ti: 8f1d8000 task.ti: 8f1d8000
  ...
  Call Trace:
  [<8010edbc>] resume+0x5c/0x280
  [<80481e0c>] __schedule+0x370/0x800
  [<80104838>] work_resched+0x8/0x2c

Fix by consistently clearing both flags in both functions.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7309/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:45 +02:00
Paul Burton 762a1f4388 MIPS: disable preemption whilst initialising MSA
Preemption must be disabled throughout the process of enabling the FPU,
enabling MSA & initialising the vector registers. Without doing so it
is possible to lose the FPU or MSA whilst initialising them causing
that initialisation to fail.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7307/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:44 +02:00
Paul Burton 3587ea888b MIPS: ensure MSA gets disabled during boot
The kernel relies upon MSA being disabled when a task begins running,
so that it can initialise or restore context in response to the
resulting MSA disabled exception. Previously the state of MSA following
boot was left as it was before the kernel ran, where MSA could
potentially have been enabled. Explicitly disable it during boot to
prevent any problems.

As a nice side effect the code reads a little better too.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7306/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:44 +02:00
Paul Burton 732c0c3c70 MIPS: fix MSA context for tasks which don't use FP first
If a task does not execute scalar FP instructions prior to using MSA
then the flags indicating that the task has live MSA context were not
being set. The upper 64b of each vector register would then be lost
upon the tasks first context switch after using MSA.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7500/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:44 +02:00
Paul Burton c9017757c5 MIPS: init upper 64b of vector registers when MSA is first used
When a task first makes use of MSA we need to ensure that the upper
64b of the vector registers are set to some value such that no
information can be leaked to it from the previous task to use MSA
context on the CPU. The architecture formerly specified that these
bits would be cleared to 0 when a scalar FP instructions wrote to the
aliased FP registers, which would have implicitly handled this as the
kernel restored scalar FP context. However more recent versions of the
specification now state that the value of the bits in such cases is
unpredictable. Initialise them explictly to be sure, and set all the
bits to 1 rather than 0 for consistency with the least significant
64b.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7497/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:44 +02:00
Paul Burton b83406735a MIPS: preserve scalar FP CSR when switching vector context
Switching the vector context implicitly saves & restores the state of
the aliased scalar FP data registers, however the scalar FP control
& status register is distinct from the MSA control & status register.
In order to allow scalar FP to function correctly in programs using
MSA, the scalar CSR needs to be saved & restored along with the MSA
vector context.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7301/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:43 +02:00
Paul Burton f7a46fa7bb MIPS: save/restore MSACSR register on context switch
I added a field for the MSACSR register in struct mips_fpu_struct, but
never actually made use of it... This is a clear bug. Save and restore
the MSACSR register along with the vector registers.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7300/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:43 +02:00
Jeffrey Deans 31521a7a64 MIPS: GIC: Generalise check for pending interrupts
Move most of the functionality of gic_get_int() into a new function
gic_get_int_mask() which takes a bitmask of interrupts in which the
caller is interested, and returns the subset which are pending for the
current CPU.

This allows CP0 IRQ dispatch routines to check only the GIC interrupts
which are routed to a particular CPU interrupt input.

gic_get_int() is reimplemented using gic_get_int_mask() and is retained
for use by any platforms for which gic_get_int() is sufficient.

Signed-off-by: Jeffrey Deans <jeffrey.deans@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7376/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:41 +02:00
Jeffrey Deans 6096e114f5 MIPS: GIC: Prevent array overrun
A GIC interrupt which is declared as having a GIC_MAP_TO_NMI_MSK
mapping causes the cpu parameter to gic_setup_intr() to be increased
to 32, causing memory corruption when pcpu_masks[] is written to again
later in the function.

Signed-off-by: Jeffrey Deans <jeffrey.deans@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: stable@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7375/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:40 +02:00
Jeffrey Deans b0a88ae502 MIPS: GIC: Remove GIC_FLAG_IPI
irq-gic.c:gic_get_int() masks out interrupts from the pending set which
aren’t in the pcpu_mask. Only interrupts marked with GIC_FLAG_IPI were
set in pcpu_mask, meaning that peripheral interrupts also had to be
marked as IPIs. Remove the use of GIC_FLAG_IPI and allow the flags
member of struct gic_intr_map to be zero.

Signed-off-by: Jeffrey Deans <jeffrey.deans@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7374/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:40 +02:00
Jeffrey Deans 822350bc90 MIPS: GIC: move GIC interrupt bitmap declarations
Several bitmaps are declared in arch/mips/include/asm/gic.h, but the
scope of their use is limited to arch/mips/kernel/irq-gic.c. Move the
declarations from the header file to the C file.

Signed-off-by: Jeffrey Deans <jeffrey.deans@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7372/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:40 +02:00
Leonid Yegoshin 6575b1d417 MIPS: kernel: cpu-probe: Detect unique RI/XI exceptions
Detect if the core supports unique exception codes for the
Read-Inhibit and Execute-Inhibit exceptions and set the
option accordingly. The RI/XI exception support is detected
by setting the 27th bit (IEC) of the PageGrain C0 register
and reading back the value of that register to verify the
bit is enabled.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7340/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:40 +02:00
Leonid Yegoshin 5890f70f15 MIPS: Use dedicated exception handler if CPU supports RI/XI exceptions
Use the regular tlb_do_page_fault_0 (no write) handler to handle
the RI and XI exceptions. Also skip the RI/XI validation check
on TLB load handler since it's redundant when the CPU has
unique RI/XI exceptions.

Singed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7339/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:39 +02:00
Markos Chandras 3d528b326d MIPS: kernel: cpu-probe: Add support for the HardWare Table Walker
Detect if the core implements the HTW and set the option accordingly.
Also, add a new kernel parameter called 'nohtw' allowing
the user to disable the htw support and fallback to the software
refill handler.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7335/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:39 +02:00
Markos Chandras e647e6b5b3 MIPS: cpu: Add new cpu option for Hardware Table Walker.
Moreover, report hardware page table walker support as 'htw' in the ASE
list of /proc/cpuinfo, if the core implements this feature.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7334/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:38 +02:00
James Hogan 560b461be1 MIPS: perf: Add hardware events for P5600
Add cases in perf_event_mipsxx.c for CPU_P5600. All the event numbers
listed for proAptiv also apply to P5600, so we use mipsxxcore_event_map2
and mipsxxcore_cache_map2 too, but the P5600 has 8-bit event numbers so
bit 8 (256) of the user ABI config is used for the parity bit (to
specify odd/even counter events).

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7242/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:38 +02:00
James Hogan 67dca66751 MIPS: perf: Allow for more perf events
In mipsxx_pmu_map_raw_event(), set event_id to base_id after the cpu
type conditional code to allow that code to override the base_id to use
more bits from the config and a higher bit for parity.

This will allow cores with up to 512 events between all even/odd
counters (an 8-bit event id) such as P5600 to use bit 8 for parity.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7243/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-02 00:06:38 +02:00