Commit Graph

2361 Commits

Author SHA1 Message Date
Rabin Vincent e54ad8c562 MIPS: Don't add leading spacing to command lines
The leading spaces don't affect functionality but are unnecessary.

Signed-off-by: Rabin Vincent <rabinv@axis.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13180/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:20 +02:00
James Hogan 105c22c5cf MIPS: genex: Indent delay slots & clean whitespace
Various branches and jumps in noreorder parts of genex.S don't have
their delay slot instructions indented conventionally with the extra
space.

Fix these, as well as various other inconsistent whitespace problems in
this file, such as spaces used after some opcodes instead of a tab.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13196/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:20 +02:00
Paul Burton 2db003a5dd MIPS: Support extended ASIDs
Add support for extended ASIDs as determined by the Config4.AE bit.
Since the only supported CPUs known to implement this are Netlogic XLP
and MIPS I6400, select this variable ASID support based upon
CONFIG_CPU_XLP and CONFIG_CPU_MIPSR6.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Jayachandran C. <jchandra@broadcom.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13211/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:20 +02:00
Paul Burton 4edf00a46b MIPS: Retrieve ASID masks using function accepting struct cpuinfo_mips
In preparation for supporting variable ASID masks, retrieve ASID masks
using functions in asm/cpu-info.h which accept struct cpuinfo_mips. This
will allow those functions to determine the ASID mask based upon the CPU
in a later patch. This also allows for the r3k & r8k cases to be handled
in Kconfig, which is arguably cleaner than the previous #ifdefs.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13210/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:20 +02:00
James Hogan 9b5c339958 MIPS: Add & use CP0_EntryHi ASID definitions
Add definitions for the ASID field in CP0_EntryHi (along with the soon
to be used ASIDX field), and use them in a few previously hardcoded
cases.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Manuel Lauss <manuel.lauss@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13205/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:18 +02:00
Sergey Ryazanov e8b5325ca3 MIPS: make PCI_DMA_BUS_IS_PHYS=1 constant
No one of supported MIPS machines has an IOMMU unit, so we can safely define
PCI_DMA_BUS_IS_PHYS = 1. Also remove iommu flag from the pci controller
structure, since it is useless.

Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Cc: Linux MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/7604/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:17 +02:00
Leonid Yegoshin 7939469da2 MIPS64: signal: Fix o32 sigaction syscall
MIPS32 o32 ABI sigaction() processing on MIPS64 n64 kernel was incorrectly
set to processing aka rt_sigaction() variant only.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: paul.burton@imgtec.com
Cc: richard@nod.at
Cc: luto@amacapital.net
Cc: alex.smith@imgtec.com
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: mpe@ellerman.id.au
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11321/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:16 +02:00
Tony Wu 201233e6b5 MIPS: traps: remove unused variable
flags is indeed unused.

Signed-off-by: Tony Wu <tung7970@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11699/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:15 +02:00
Huacai Chen 380cd582c0 MIPS: Loongson-3: Fast TLB refill handler
Loongson-3A R2 has pwbase/pwfield/pwsize/pwctl registers in CP0 (this
is very similar to HTW) and lwdir/lwpte/lddir/ldpte instructions which
can be used for fast TLB refill.

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

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Steven J . Hill <sjhill@realitydiluted.com>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12754/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:15 +02:00
Huacai Chen 06e4814eec MIPS: Loongson: Invalidate special TLBs when needed
Loongson-2 has a 4 entry itlb which is a subset of jtlb, Loongson-3 has
a 4 entry itlb and a 4 entry dtlb which are subsets of jtlb. We should
write diag register to invalidate itlb/dtlb when flushing jtlb because
itlb/dtlb are not totally transparent to software.

For Loongson-3A R2 (and newer), we should invalidate ITLB, DTLB, VTLB
and FTLB before we enable/disable FTLB.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Steven J . Hill <sjhill@realitydiluted.com>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12753/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:14 +02:00
Huacai Chen b2edcfc814 MIPS: Loongson: Add Loongson-3A R2 basic support
Loongson-3 CPU family:

Code-name       Brand-name       PRId
Loongson-3A R1  Loongson-3A1000  0x6305
Loongson-3A R2  Loongson-3A2000  0x6308
Loongson-3B R1  Loongson-3B1000  0x6306
Loongson-3B R2  Loongson-3B1500  0x6307

Features of R2 revision of Loongson-3A:

  - Primary cache includes I-Cache, D-Cache and V-Cache (Victim Cache).
  - I-Cache, D-Cache and V-Cache are 16-way set-associative, linesize is
     64 bytes.
  - 64 entries of VTLB (classic TLB), 1024 entries of FTLB (8-way
     set-associative).
  - Supports DSP/DSPv2 instructions, UserLocal register and Read-Inhibit/
     Execute-Inhibit.

[ralf@linux-mips.org: Resolved merge conflicts.]

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Steven J . Hill <sjhill@realitydiluted.com>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12751/
Patchwork: https://patchwork.linux-mips.org/patch/13136/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:14 +02:00
James Hogan 50af501cd8 MIPS: Add and use watch register field definitions
The files watch.c and ptrace.c contain various magic masks for
WatchLo/WatchHi register fields. Add some definitions to mipsregs.h for
these registers and make use of them in both watch.c and ptrace.c,
hopefully making them more readable.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12729/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:13 +02:00
James Hogan e233c73378 MIPS: Add and use CAUSEF_WP definition
do_watch() clears bit 22 of cause without using a CAUSEF_* definition
from mipsregs.h. Add a definition for this bit (CAUSEF_WP) and make use
of it. Also use clear_c0_cause() instead of manual read/modify/write.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12728/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:13 +02:00
Andrzej Hajda ba837d3871 MIPS: module: fix incorrect IS_ERR_VALUE macro usages
IS_ERR_VALUE macro should be used only with unsigned long type.
Specifically it works incorrectly with longer types.

The patch follows conclusion from discussion on LKML [1][2].

[1]: http://permalink.gmane.org/gmane.linux.kernel/2120927
[2]: http://permalink.gmane.org/gmane.linux.kernel/2150581

[ralf@linux-mips.org: While it may not immediately be obvious, the type
of st_value in the end is an unsigned long equivalent so the invocation
of IS_ERR_VALUE() was valid but I'm applying the patch anyway for
clarity.]

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12553/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:11 +02:00
Florian Fainelli 37808d62af MIPS: BMIPS: Pretty print BMIPS5200 processor name
Just to ease debugging of multiplatform kernel, make sure we print
"Broadcom BMIPS5200" for the BMIPS5200 implementation instead of
Broadcom BMIPS5000.

Fixes: 68e6a78373 ("MIPS: BMIPS: Add PRId for BMIPS5200 (Whirlwind)")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13014/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:07 +02:00
Matt Redfearn 919beb4eed MIPS: KASLR: Print relocation Information on boot
When debugging a relocated kernel, the addresses of the relocated
symbols and the offset applied is essential information. If the kernel
is compiled with debugging information, then print this information
during bootup using the same function as the panic notifier.

[ralf@linux-mips.org: Fixed spelling mistake pointed out by
Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>.]

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Aaro Koskinen <aaro.koskinen@nokia.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Cc: Jaedon Shin <jaedon.shin@gmail.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: kernel-hardening@lists.openwall.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12989/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:04 +02:00
Matt Redfearn 405bc8fd12 MIPS: Kernel: Implement KASLR using CONFIG_RELOCATABLE
This patch adds KASLR to the MIPS kernel.

Entropy is derived from the banner, which will change every build and
random_get_entropy() which should provide additional runtime entropy.
Additionally the bootloader may pass entropy via the /chosen/kaslr-seed
node in device tree.

The kernel is relocated by up to RANDOMIZE_BASE_MAX_OFFSET bytes from
its link address (PHYSICAL_START). Because relocation happens so early
in the kernel boot, the amount of physical memory has not yet been
determined. This means the only way to limit relocation within the
available memory is via Kconfig.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: kernel-hardening@lists.openwall.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12990/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:03 +02:00
Matt Redfearn 61cd52d4e4 MIPS: bootmem: When relocatable, free memory below kernel
The kernel reserves all memory before the _end symbol as bootmem,
however, once the kernel can be relocated elsewhere in memory this may
result in a large amount of wasted memory. The assumption is that the
memory between the link and relocated address of the kernel may be
released back to the available memory pool.

Memory statistics for a Malta with the kernel relocating by
16Mb, without the patch:
Memory: 105952K/131072K available (4604K kernel code, 242K rwdata,
892K rodata, 1280K init, 183K bss, 25120K reserved, 0K cma-reserved)
And with the patch:
Memory: 122336K/131072K available (4604K kernel code, 242K rwdata,
892K rodata, 1280K init, 183K bss, 8736K reserved, 0K cma-reserved)

The 16Mb offset is removed from the reserved region and added back to
the available region.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Aaro Koskinen <aaro.koskinen@nokia.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Cc: Jaedon Shin <jaedon.shin@gmail.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: kernel-hardening@lists.openwall.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12986/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:03 +02:00
Matt Redfearn af09ab5e3f MIPS: Call relocate_kernel if CONFIG_RELOCATABLE=y
If CONFIG_RELOCATABLE is enabled, call relocate_kernel.

This function will return the entry point of the relocated kernel if
copy/relocate is sucessful or the original entry point if not. The stack
pointer must then be pointed into the new image.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: kernel-hardening@lists.openwall.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12984/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:03 +02:00
Matt Redfearn 279b991b24 MIPS: Kernel: Add relocate.c
arch/mips/kernel/relocate.c contains the functions necessary to relocate
the kernel elsewhere in memory

The kernel makes a copy of itself at the new address. It uses the
relocation table inserted by the relocs tool to fix symbol references
within the new image.

If copy/relocation is sucessful then the entry point of the new kernel
is returned, otherwise fall back to starting the kernel in place.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: kernel-hardening@lists.openwall.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12985/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:02 +02:00
Matt Redfearn 069fd76627 MIPS: Reserve space for relocation table
When CONFIG_RELOCATABLE is enabled, add a new section in the memory map
to be filled with relocation data.

CONFIG_RELOCATION_TABLE_SIZE allows the amount of space reserved to be
adjusted if necessary.

The relocs tool will populate this reserved space with relocation
information. The space is reserved within the elf by filling it with
0's, and an invalid entry is left at the start of the space such that
kernel relocation will be aborted if the table is empty.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Aaro Koskinen <aaro.koskinen@nokia.com>
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: kernel-hardening@lists.openwall.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12982/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:02 +02:00
Matt Redfearn a400bed6d1 MIPS: scall: Handle seccomp filters which redirect syscalls
Commit d218af7849 ("MIPS: scall: Always run the seccomp syscall
filters") modified the syscall code to always call the seccomp filters,
but missed the case where a filter may redirect the syscall, as
revealed by the seccomp_bpf self test.

The syscall path now restores the syscall from the stack after the
filter rather than saving it locally. Syscall number checking and
syscall function table lookup is done after the filter may have run such
that redirected syscalls are also checked, and executed.

The regular path of syscall number checking and pointer lookup is also
made more consistent between ABIs with scall64-64.S being the reference.

With this patch in place, the seccomp_bpf self test now passes
TRACE_syscall.syscall_redirected and TRACE_syscall.syscall_dropped on
all MIPS ABIs.

Fixes: d218af7849 ("MIPS: scall: Always run the seccomp syscall filters")
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Eric B Munson <emunson@akamai.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: IMG-MIPSLinuxKerneldevelopers@imgtec.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12916/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:00 +02:00
Matt Redfearn 5050e91fa6 MIPS: Support sending SIG_SYS to 32bit userspace from 64bit kernel
The seccomp_bpf self test revealed that a 64bit kernel delivered an
invalid SIG_SYS to a 32bit userspace, because it was falling into the
default of the switch statement. Add a case to handle delivering the
signal.

With this patch, the seccomp_bpf self test now passes the TRAP.handler
case with O32 and N32 userlands.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Amanieu d'Antras <amanieu@gmail.com>
Cc: Alex Smith <alex.smith@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: IMG-MIPSLinuxKerneldevelopers@imgtec.com
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12915/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:00 +02:00
Zubair Lutfullah Kakakhel b5a6455cde MIPS: Detect DSP v3 support
DSPv3 is supported on all MIPSr6 systems which indicate support for DSPv2.

This doesn't require any changes to the kernel's handling of DSP
resources. The patch is to detect support and indicate it in /proc/cpuinfo

DSP v3 introduces a new instruction BPOSGE32C

Signed-off-by: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12918/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:57 +02:00
Florian Fainelli 738a3f7902 MIPS: BMIPS: Add early CPU initialization code
Port the stblinux-3.3 code to perform a bunch of CPU-specific initialization,
make it compatible with run-time detection of the CPU, and unroll the
brcmstb-specific macros: BDEV_RB(), BDEV_UNSET.

The "pref 30" disabling is done as a quirk. This is a preliminary change to
allow the use of the "rotr" instruction gated by cpu_has_rixi.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: john@phrozen.org
Cc: cernekee@gmail.com
Cc: jon.fraser@broadcom.com
Cc: pgynther@google.com
Cc: paul.burton@imgtec.com
Cc: ddaney.cavm@gmail.com
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12504/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:55 +02:00
Ralf Baechle 04cc89d120 MIPS: Make flush_thread
Avoids function calls to an empty function.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:54 +02:00
Paul Burton 5d3c792583 MIPS: Support R_MIPS_PC{16,21,26} rel-style relocs
MIPS32 code uses rel-style relocs, and MIPS32r6 modules may include
R_MIPS_PC16, R_MIPS_PC21 & R_MIPS_PC26 relocations. We thus need to
support these relocations in order to load MIPS32r6 kernel modules. This
patch adds such support, which is similar to the rela-style support in
module-rela.c but making use of the implicit addend from the instruction
encoding.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Steven J. Hill <sjhill@realitydiluted.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12435/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:54 +02:00
Paul Burton ad8319ea46 MIPS: Support R_MIPS_PC{21,26} rela-style relocs
MIPS64 code uses rela-style relocs, and MIPS64r6 modules may include the
new R_MIPS_PC21 & R_MIPS_PC26 relocations. We thus need to support these
relocations in order to load MIPS64r6 kernel modules. They are similar
to the existing R_MIPS_PC16 relocation but applying to a wider field.
Implement support for them by genericising the existing R_MIPS_PC16
implementation such that it can be used for different field widths, and
calling it for all 3 reloc types.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Alex Smith <alex.smith@imgtec.com>
Cc: Steven J. Hill <sjhill@realitydiluted.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12434/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:54 +02:00
Steven J. Hill 55d791f37c MIPS: module: Make consistent use of pr_*()
The module relocation handling code has inconsistent use of printk() and
pr_*() functions. Convert printk() calls to use pr_err() and pr_warn().

[paul.burton@imgtec.com: Do the same thing in module.c]

Signed-off-by: Steven J. Hill <sjhill@realitydiluted.com>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12433/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:53 +02:00
Paul Burton 43aff742b6 MIPS: Probe the M6250 CPU
Support probing the M6250 CPU now that cases for handling it have been
added where required in the core MIPS kernel code.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: Joshua Kinard <kumba@gentoo.org>
Cc: 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/12375/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:53 +02:00
Paul Burton eba20a3a37 MIPS: Probe the P6600 core
Support probing the P6600 core now that cases for handling it have been
added throughout the core MIPS kernel code.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: 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/12344/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:52 +02:00
Paul Burton 1091bfa20b MIPS: Add P6600 cases to CPU switch statements
Add cases supporting the P6600 CPU to various switch statements in
core MIPS kernel code that define behaviour dependent upon the CPU.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Joshua Kinard <kumba@gentoo.org>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Petri Gynther <pgynther@google.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12343/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:52 +02:00
Paul Burton 6609ccdc85 MIPS: smp-cps: Stop printing EJTAG exceptions to UART
When CONFIG_MIPS_CPS_NS16550 is enabled, some register state is dumped
to the UART when an exception is taken via the BEV on secondary cores.
EJTAG exceptions are architecturally expected to be handled by the BEV
even when Status.BEV is 0. This effectively means that if userland
executes an sdbbp instruction on a secondary core then the kernel dumps
register state to the UART even though the exception is perfectly normal
& expected. Prevent this by simply not dumping information to the UART
for EJTAG exceptions.

Fixes: 609cf6f229 ("MIPS: CPS: Early debug using an ns16550-compatible UART")
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12341/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:51 +02:00
Paul Burton 6422a91385 MIPS: smp-cps: Add nothreads kernel parameter
When debugging a new system or core it can be useful to disable the use
of multithreading. Introduce a "nothreads" kernel command line parameter
that can be set in order to do so.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Niklas Cassel <niklas.cassel@axis.com>
Cc: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12340/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:50 +02:00
Paul Burton 5a3e7c02d8 MIPS: smp-cps: Support MIPSr6 Virtual Processors
Introduce support for bringing up Virtual Processors in MIPSr6 systems
as CPUs, much like their VPE parallel from the now-deprecated MT ASE.
The existing mips_cps_boot_vpes function fits the MIPSr6 architecture
pretty well - it can now simply write the mask of running VPs to the
VC_RUN register, rather than looping through each & starting or stopping
as appropriate as is done for VPEs from the MT ASE. Thus the VP support
is in general an extension & simplification of the existing MT ASE VPE
(aka SMVP) support.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Niklas Cassel <niklas.cassel@axis.com>
Cc: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12339/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:50 +02:00
Paul Burton 87a70bcdb4 MIPS: smp-cps: Skip core setup if coherent
In preparation for supporting MIPSr6 multithreading (ie. VPs) which will
begin execution from the core reset vector, skip core level setup if the
core is already coherent. This is never the case when a core is first
started, since boot_core explicitly clears the cores GCR_Cx_COH_EN
register, and always the case when secondary VPs start since the first
VP to start will have enabled coherence after initialising the core &
its caches.

One notable side effect of this patch is that eva_init gets called
slightly earlier, prior to mips_cps_core_init rather than after it.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12338/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:50 +02:00
Paul Burton f12401d721 MIPS: smp-cps: Pull boot config retrieval out of mips_cps_boot_vpes
The mips_cps_boot_vpes function previously included code to retrieve
pointers to the core & VPE boot configuration structs. These structures
were used both by mips_cps_boot_vpes and by its mips_cps_core_entry
callsite. In preparation for skipping the call to mips_cps_boot_vpes on
some invocations of mips_cps_core_entry, pull the calculation of those
pointers out into a separate function such that it can continue to be
shared.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Niklas Cassel <niklas.cassel@axis.com>
Cc: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12337/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:50 +02:00
Paul Burton 3dbc997161 MIPS: smp-cps: Pull cache init into a function
In preparation for further modifications to mips_cps_core_entry, pull
the L1 cache initialisation out into a separate function. This both
makes the code in mips_cps_core_entry read more clearly, particularly
when modifying it, and shortens it which will become important as code
is added that needs to continue to fit within the reset vector.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12336/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:49 +02:00
Paul Burton ba1c0a490a MIPS: smp-cps: Ensure our VP ident calculation is correct
When bringing up a CPU, ensure that its local ID as provided by the GIC
matches up with our calculation of it. This is vital, since if the
condition doesn't hold then we won't have configured interrupts
correctly for the VP.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Niklas Cassel <niklas.cassel@axis.com>
Cc: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12335/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:49 +02:00
Markos Chandras 0f2a148448 MIPS: pm-cps: Avoid offset overflow on MIPSr6
This is similar to commit 934c79231c ("MIPS: asm: r4kcache: Add MIPS
R6 cache unroll functions"). The CACHE instruction has been redefined
for MIPSr6 and it reduced its offset field to 8 bits. This leads to
micro-assembler field overflow warnings when booting SMP MIPSr6 cores
like the following one:

Call Trace:
[<ffffffff8010af88>] show_stack+0x68/0x88
[<ffffffff8056ddf0>] dump_stack+0x68/0x88
[<ffffffff801305bc>] warn_slowpath_common+0x8c/0xc8
[<ffffffff80130630>] warn_slowpath_fmt+0x38/0x48
[<ffffffff80125814>] build_insn+0x514/0x5c0
[<ffffffff806ee134>] cps_gen_cache_routine.isra.3+0xe0/0x1b8
[<ffffffff806ee570>] cps_pm_init+0x364/0x9ec
[<ffffffff80100538>] do_one_initcall+0x90/0x1a8
[<ffffffff806e8c14>] kernel_init_freeable+0x160/0x21c
[<ffffffff8056b6a0>] kernel_init+0x10/0xf8
[<ffffffff801059f8>] ret_from_kernel_thread+0x14/0x1c

We fix this by incrementing the base register on every loop.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12329/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:48 +02:00
Markos Chandras 04d83f9485 MIPS: traps: Make sure secondary cores have a sane ebase register
We shouldn't trust that the secondary cores will have a sane ebase register
(either from the bootloader or during the hardware design phase) so use the
ebase address as calculated by the boot CPU.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Petri Gynther <pgynther@google.com>
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12328/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:48 +02:00
Paul Burton f270d881fa MIPS: Detect MIPSr6 Virtual Processor support
MIPSr6 introduces support for "Virtual Processors", which are
conceptually similar to VPEs from the now-deprecated MT ASE. Detect
whether the system supports VPs using the VP bit in Config5, adding
cpu_has_vp for use by later patches.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: Joshua Kinard <kumba@gentoo.org>
Cc: Steven J. Hill <sjhill@realitydiluted.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12327/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:47 +02:00
Aaro Koskinen 99a7a234c8 MIPS: panic immediately when panic_on_oops
MIPS wants to sleep 5 seconds before panicking when panic_on_oops is set,
with no apparent reason. Remove this feature, since some users may want
their systems to fail as quickly as possible.

Users who want to delay reboot after panic can use PANIC_TIMEOUT.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-mips@linux-mips.org
Cc: linux-parisc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12845/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:44 +02:00
David Daney b8c8f66507 MIPS: Add CPU identifiers and probing for Cavium CN73xx and CNF75xx processors.
Add new processor identifiers for Cavium CN73xx and CNF75xx
processors, and probe for them in cpu-probe.c

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12311/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:01:38 +02:00
Paul Burton 8a3c8b48ac MIPS: Use copy_s.fmt rather than copy_u.fmt
In revision 1.12 of the MSA specification, the copy_u.w instruction has
been removed for MIPS32 & the copy_u.d instruction has been removed for
MIPS64. Newer toolchains (eg. Codescape SDK essentials 2015.10) will
complain about this like so:

arch/mips/kernel/r4k_fpu.S:290: Error: opcode not supported on this
processor: mips32r2 (mips32r2) `copy_u.w $1,$w26[3]'

Since we always copy to the width of a GPR, simply use copy_s instead of
copy_u to fix this.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 4.3.x+
Patchwork: https://patchwork.linux-mips.org/patch/13061/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:04 +02:00
Leonid Yegoshin 41fa29e4d8 MIPS64: R6: R2 emulation bugfix
Error recovery pointers for fixups was improperly set as ".word"
which is unsuitable for MIPS64.

Replaced by STR(PTR)

[ralf@linux-mips.org: Apply changes as requested in the review process.]

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Markos Chandras <markos.chandras@imgtec.com>
Fixes: b0a668fb20 ("MIPS: kernel: mips-r2-to-r6-emul: Add R2 emulator for MIPS R6")
Cc: macro@linux-mips.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: <stable@vger.kernel.org> # 4.0+
Patchwork: https://patchwork.linux-mips.org/patch/9911/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:04 +02:00
Huacai Chen a95d069204 MIPS: Reserve nosave data for hibernation
After commit 92923ca3aa ("mm: meminit: only set page reserved
in the memblock region"), the MIPS hibernation is broken. Because pages
in nosave data section should be "reserved", but currently they aren't
set to "reserved" at initialization. This patch makes hibernation work
again.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Steven J . Hill <sjhill@realitydiluted.com>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12888/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:03 +02:00
James Hogan a7e89326b4 MIPS: Fix watchpoint restoration
Commit f51246efee ("MIPS: Get rid of finish_arch_switch().") moved the
__restore_watch() call from finish_arch_switch() (i.e. after resume()
returns) to before the resume() call in switch_to(). This results in
watchpoints only being restored when a task is descheduled, preventing
the watchpoints from being effective most of the time, except due to
chance before the watchpoints are lazily removed.

Fix the call sequence from switch_to() through to
mips_install_watch_registers() to pass the task_struct pointer of the
next task, instead of using current. This allows the watchpoints for the
next (non-current) task to be restored without reintroducing
finish_arch_switch().

Fixes: f51246efee ("MIPS: Get rid of finish_arch_switch().")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 4.3.x-
Patchwork: https://patchwork.linux-mips.org/patch/12726/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:02 +02:00
James Hogan 81a76d7119 MIPS: Avoid using unwind_stack() with usermode
When showing backtraces in response to traps, for example crashes and
address errors (usually unaligned accesses) when they are set in debugfs
to be reported, unwind_stack will be used if the PC was in the kernel
text address range. However since EVA it is possible for user and kernel
address ranges to overlap, and even without EVA userland can still
trigger an address error by jumping to a KSeg0 address.

Adjust the check to also ensure that it was running in kernel mode. I
don't believe any harm can come of this problem, since unwind_stack() is
sufficiently defensive, however it is only meant for unwinding kernel
code, so to be correct it should use the raw backtracing instead.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 3.15+
Patchwork: https://patchwork.linux-mips.org/patch/11701/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
(cherry picked from commit d2941a975ac745c607dfb590e92bb30bc352dad9)
2016-05-09 12:00:02 +02:00
James Hogan a816b306c6 MIPS: Don't unwind to user mode with EVA
When unwinding through IRQs and exceptions, the unwinding only continues
if the PC is a kernel text address, however since EVA it is possible for
user and kernel address ranges to overlap, potentially allowing
unwinding to continue to user mode if the user PC happens to be in the
kernel text address range.

Adjust the check to also ensure that the register state from before the
exception is actually running in kernel mode, i.e. !user_mode(regs).

I don't believe any harm can come of this problem, since the PC is only
output, the stack pointer is checked to ensure it resides within the
task's stack page before it is dereferenced in search of the return
address, and the return address register is similarly only output (if
the PC is in a leaf function or the beginning of a non-leaf function).

However unwind_stack() is only meant for unwinding kernel code, so to be
correct the unwind should stop there.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 3.15+
Patchwork: https://patchwork.linux-mips.org/patch/11700/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:02 +02:00
Florian Fainelli f6cc0ee98b MIPS: BMIPS: Fill in current_cpu_data.core
Read the core ID in bmips_smp_finish() for BMIPS5000 CPUs to get appropriate
processor parenting in set_cpu_sibling_map().

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: john@phrozen.org
Cc: cernekee@gmail.com
Cc: jon.fraser@broadcom.com
Cc: jaedon.shin@gmail.com
Cc: dragan.stancevic@gmail.com
Cc: jogo@openwrt.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12380/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:01 +02:00
Ralf Baechle f241265fdc MIPS: BMIPS: Make whitespacely correct.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:01 +02:00
Florian Fainelli 21b30c00f3 MIPS: BMIPS: Add Whirlwind (BMIPS5200) initialization code
Import bmips_5xxx_init.S from the stblinux-3.3 tree, and to make sure that this
would work nicely with a BMIPS multiplatform kernel (with BMIPS330, BMIPS43XX
and BMIPS5000 enabled), update soft_reset to check for the BMIPS5200 processor
id (PRID_IMP_BMIPS5200) and execute bmips_5xxx_init for these processors to
bring them online.

Tested on 7425, 7429 and 7435 with CPU hotplug. 7435 SMP still needs some
additional changes in the L1 interrupt area to work properly with interrupt
affinity.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: john@phrozen.org
Cc: cernekee@gmail.com
Cc: jon.fraser@broadcom.com
Cc: jaedon.shin@gmail.com
Cc: dragan.stancevic@gmail.com
Cc: jogo@openwrt.org
Patchwork: https://patchwork.linux-mips.org/patch/12377/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:01 +02:00
Florian Fainelli cbbda6e7c9 MIPS: BMIPS: Fix PRID_IMP_BMIPS5000 masking for BMIPS5200
BMIPS5000 have a PrID value of 0x5A00 and BMIPS5200 have a PrID value of
0x5B00, which, masked with 0x5A00, returns 0x5A00. Update all conditionals on
the PrID to cover both variants since we are going to need this to enable
BMIPS5200 SMP. The existing check, masking with 0xFF00 would not cover
BMIPS5200 at all.

Fixes: 68e6a78373 ("MIPS: BMIPS: Add PRId for BMIPS5200 (Whirlwind)")
Fixes: 6465460c92 ("MIPS: BMIPS: change compile time checks to runtime checks")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: john@phrozen.org
Cc: cernekee@gmail.com
Cc: jogo@openwrt.org
Cc: jaedon.shin@gmail.com
Cc: jfraser@broadcom.com
Cc: pgynther@google.com
Cc: dragan.stancevic@gmail.com
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12279/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:01 +02:00
Paul Burton 578bffc82e MIPS: Don't BUG_ON when no IPI domain is found
Commit fbde2d7d82 ("MIPS: Add generic SMP IPI support") introduced
code that BUG_ON's in the case of a kernel that supports IPI domains but
does not have one at runtime. This case is possible on Malta where for
IPIs we may use either the GIC (which has an IPI IRQ domain
implementation) or core-local software interrupts between VPEs (which do
not currently have an IPI IRQ domain implementation). We can not know
which will be used until runtime when we know whether a GIC is actually
present, and if we run on a system with multiple VPEs and no GIC then
the BUG_ON is hit.

Commit 19fb5818ed ("IPS: Fix broken malta qemu") worked around this
for the single-core single-VPE case typically seen using QEMU, but does
not catch the multi-VPE case. This patch removes the insufficient CPU
presence check that was added and works around the bug differently,
effectively reverting that commit.

A simple way to reproduce this bug is by using QEMU, which partially
implements the MT ASE but does not implement the GIC as of version 2.5.
Using "-cpu 34Kf -smp 2" will present a system with 2 VPEs in one core &
no GIC, hitting the BUG_ON.

Given that we're post-merge-window on the way to v4.6, avoid this by
just returning from mips_smp_ipi_init when no IPI IRQ domain is found.
Ideally at some point all IPI implementations would be converted to the
same IPI IRQ domain interface & we'd be able to restore the check.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qsyousef@gmail.com>
Fixes: fbde2d7d82 ("MIPS: Add generic SMP IPI support")
Fixes: 19fb5818ed ("IPS: Fix broken malta qemu")
Reverts: 19fb5818ed ("IPS: Fix broken malta qemu")
Cc: Qais Yousef <qsyousef@gmail.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Alex Smith <alex.smith@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13007/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:00 +02:00
Corey Minyard c80e1b62ff MIPS: Fix crash registers on non-crashing CPUs
As part of handling a crash on an SMP system, an IPI is send to
all other CPUs to save their current registers and stop.  It was
using task_pt_regs(current) to get the registers, but that will
only be accurate if the CPU was interrupted running in userland.
Instead allow the architecture to pass in the registers (all
pass NULL now, but allow for the future) and then use get_irq_regs()
which should be accurate as we are in an interrupt.  Fall back to
task_pt_regs(current) if nothing else is available.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13050/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-09 12:00:00 +02:00
Arnaldo Carvalho de Melo c5dfd78eb7 perf core: Allow setting up max frame stack depth via sysctl
The default remains 127, which is good for most cases, and not even hit
most of the time, but then for some cases, as reported by Brendan, 1024+
deep frames are appearing on the radar for things like groovy, ruby.

And in some workloads putting a _lower_ cap on this may make sense. One
that is per event still needs to be put in place tho.

The new file is:

  # cat /proc/sys/kernel/perf_event_max_stack
  127

Chaging it:

  # echo 256 > /proc/sys/kernel/perf_event_max_stack
  # cat /proc/sys/kernel/perf_event_max_stack
  256

But as soon as there is some event using callchains we get:

  # echo 512 > /proc/sys/kernel/perf_event_max_stack
  -bash: echo: write error: Device or resource busy
  #

Because we only allocate the callchain percpu data structures when there
is a user, which allows for changing the max easily, its just a matter
of having no callchain users at that point.

Reported-and-Tested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/20160426002928.GB16708@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-27 10:20:39 -03:00
Maciej W. Rozycki 3d50a7fb42 MIPS: traps.c: Verify the ISA for microMIPS RDHWR emulation
Make sure it's the microMIPS rather than MIPS16 ISA before emulating
microMIPS RDHWR.  Mostly needed as an optimisation for configurations
where `cpu_has_mmips' is hardcoded to 0 and also a good measure in case
we add further microMIPS instructions to emulate in the future, as the
corresponding MIPS16 encoding is ADDIUSP, not supposed to trap.

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12282/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-04-04 15:25:34 +02:00
Paul Burton 04211a5746 MIPS: Bail on unsupported module relocs
When an unsupported reloc is encountered in a module, we currently
blindly branch to whatever would be at its entry in the reloc handler
function pointer arrays. This may be NULL, or if the unsupported reloc
has a type greater than that of the supported reloc with the highest
type then we'll dereference some value after the function pointer array
& branch to that. The result is at best a kernel oops.

Fix this by checking that the reloc type has an entry in the function
pointer array (ie. is less than the number of items in the array) and
that the handler is non-NULL, returning an error code to fail the module
load if no handler is found.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12432/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-04-03 12:32:10 +02:00
Maciej W. Rozycki 3b143cca6e MIPS: traps: Correct the SIGTRAP debug ABI in `do_watch' and `do_trap_or_bp'
Follow our own rules set in <asm/siginfo.h> for SIGTRAP signals issued
from `do_watch' and `do_trap_or_bp' by setting the signal code to
TRAP_HWBKPT and TRAP_BRKPT respectively, for Watch exceptions and for
those Breakpoint exceptions whose originating BREAK instruction's code
does not have a special meaning.  Keep Trap exceptions unaffected as
these are not debug events.

No existing user software is expected to examine signal codes for these
signals as SI_KERNEL has been always used here.  This change makes the
MIPS port more like other Linux ports, which reduces the complexity and
provides for performance improvement in GDB.

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Luis Machado <lgustavo@codesourcery.com>
Cc: linux-mips@linux-mips.org
Cc: gdb@sourceware.org
Patchwork: https://patchwork.linux-mips.org/patch/12758/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-04-03 12:32:09 +02:00
Adam Buchbinder 92a76f6d85 MIPS: Fix misspellings in comments.
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: trivial@kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12617/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-04-03 12:32:09 +02:00
Ralf Baechle 62d8e64423 MIPS: Wire up preadv2 and pwrite2 syscalls.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-04-03 09:41:34 +02:00
Paul Burton fa8ff601d7 MIPS: Fix MSA ld unaligned failure cases
Copying the content of an MSA vector from user memory may involve TLB
faults & mapping in pages. This will fail when preemption is disabled
due to an inability to acquire mmap_sem from do_page_fault, which meant
such vector loads to unmapped pages would always fail to be emulated.
Fix this by disabling preemption later only around the updating of
vector register state.

This change does however introduce a race between performing the load
into thread context & the thread being preempted, saving its current
live context & clobbering the loaded value. This should be a rare
occureence, so optimise for the fast path by simply repeating the load if
we are preempted.

Additionally if the copy failed then the failure path was taken with
preemption left disabled, leading to the kernel typically encountering
further issues around sleeping whilst atomic. The change to where
preemption is disabled avoids this issue.

Fixes: e4aa1f153a "MIPS: MSA unaligned memory access support"
Reported-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: James Cowgill <James.Cowgill@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: stable <stable@vger.kernel.org> # v4.3
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12345/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-03-29 14:18:18 +02:00
Qais Yousef 19fb5818ed MIPS: Fix broken malta qemu
Malta defconfig compiles with GIC on. Hence when compiling for SMP it causes
the new IPI code to be activated. But on qemu malta there's no GIC causing a
BUG_ON(!ipidomain) to be hit in mips_smp_ipi_init().

Since in that configuration one can only run a single core SMP (!), skip IPI
initialisation if we detect that this is the case. It is a sensible
behaviour to introduce and should keep such possible configuration to run
rather than die hard unnecessarily.

Signed-off-by: Qais Yousef <qsyousef@gmail.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12892/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-03-29 14:18:18 +02:00
Alexander Potapenko be7635e728 arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections
KASAN needs to know whether the allocation happens in an IRQ handler.
This lets us strip everything below the IRQ entry point to reduce the
number of unique stack traces needed to be stored.

Move the definition of __irq_entry to <linux/interrupt.h> so that the
users don't need to pull in <linux/ftrace.h>.  Also introduce the
__softirq_entry macro which is similar to __irq_entry, but puts the
corresponding functions to the .softirqentry.text section.

Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-25 16:37:42 -07:00
Linus Torvalds 1a46712aa9 This is the bulk of GPIO changes for kernel v4.6:
Core changes:
 
 - The gpio_chip is now a *real device*. Until now the gpio chips
   were just piggybacking the parent device or (gasp) floating in
   space outside of the device model. We now finally make GPIO chips
   devices. The gpio_chip will create a gpio_device which contains
   a struct device, and this gpio_device struct is kept private.
   Anything that needs to be kept private from the rest of the kernel
   will gradually be moved over to the gpio_device.
 
 - As a result of making the gpio_device a real device, we have added
   resource management, so devm_gpiochip_add_data() will cut down on
   overhead and reduce code lines. A huge slew of patches convert
   almost all drivers in the subsystem to use this.
 
 - Building on making the GPIO a real device, we add the first step
   of a new userspace ABI: the GPIO character device. We take small
   steps here, so we first add a pure *information* ABI and the tool
   "lsgpio" that will list all GPIO devices on the system and all
   lines on these devices. We can now discover GPIOs properly from
   userspace. We still have not come up with a way to actually *use*
   GPIOs from userspace.
 
 - To encourage people to use the character device for the future,
   we have it always-enabled when using GPIO. The old sysfs ABI is
   still opt-in (and can be used in parallel), but is marked as
   deprecated. We will keep it around for the foreseeable future,
   but it will not be extended to cover ever more use cases.
 
 Cleanup:
 
 - Bjorn Helgaas removed a whole slew of per-architecture <asm/gpio.h>
   includes. This dates back to when GPIO was an opt-in feature and
   no shared library even existed: just a header file with proper
   prototypes was provided and all semantics were up to the arch to
   implement. These patches make the GPIO chip even more a proper
   device and cleans out leftovers of the old in-kernel API here
   and there. Still some cruft is left but it's very little now.
 
 - There is still some clamping of return values for .get() going
   on, but we now return sane values in the vast majority of drivers
   and the errorpath is sanitized. Some patches for powerpc, blackfin
   and unicore still drop in.
 
 - We continue to switch the ARM, MIPS, blackfin, m68k local GPIO
   implementations to use gpiochip_add_data() and cut down on code
   lines.
 
 - MPC8xxx is converted to use the generic GPIO helpers.
 
 - ATH79 is converted to use the generic GPIO helpers.
 
 New drivers:
 
 - WinSystems WS16C48
 
 - Acces 104-DIO-48E
 
 - F81866 (a F7188x variant)
 
 - Qoric (a MPC8xxx variant)
 
 - TS-4800
 
 - SPI serializers (pisosr): simple 74xx shift registers connected
   to SPI to obtain a dirt-cheap output-only GPIO expander.
 
 - Texas Instruments TPIC2810
 
 - Texas Instruments TPS65218
 
 - Texas Instruments TPS65912
 
 - X-Gene (ARM64) standby GPIO controller
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Merge tag 'gpio-v4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for kernel v4.6.  There is quite a
  lot of interesting stuff going on.

  The patches to other subsystems and arch-wide are ACKed as far as
  possible, though I consider things like per-arch <asm/gpio.h> as
  essentially a part of the GPIO subsystem so it should not be needed.

  Core changes:

   - The gpio_chip is now a *real device*.  Until now the gpio chips
     were just piggybacking the parent device or (gasp) floating in
     space outside of the device model.

     We now finally make GPIO chips devices.  The gpio_chip will create
     a gpio_device which contains a struct device, and this gpio_device
     struct is kept private.  Anything that needs to be kept private
     from the rest of the kernel will gradually be moved over to the
     gpio_device.

   - As a result of making the gpio_device a real device, we have added
     resource management, so devm_gpiochip_add_data() will cut down on
     overhead and reduce code lines.  A huge slew of patches convert
     almost all drivers in the subsystem to use this.

   - Building on making the GPIO a real device, we add the first step of
     a new userspace ABI: the GPIO character device.  We take small
     steps here, so we first add a pure *information* ABI and the tool
     "lsgpio" that will list all GPIO devices on the system and all
     lines on these devices.

     We can now discover GPIOs properly from userspace.  We still have
     not come up with a way to actually *use* GPIOs from userspace.

   - To encourage people to use the character device for the future, we
     have it always-enabled when using GPIO.  The old sysfs ABI is still
     opt-in (and can be used in parallel), but is marked as deprecated.

     We will keep it around for the foreseeable future, but it will not
     be extended to cover ever more use cases.

  Cleanup:

   - Bjorn Helgaas removed a whole slew of per-architecture <asm/gpio.h>
     includes.

     This dates back to when GPIO was an opt-in feature and no shared
     library even existed: just a header file with proper prototypes was
     provided and all semantics were up to the arch to implement.  These
     patches make the GPIO chip even more a proper device and cleans out
     leftovers of the old in-kernel API here and there.

     Still some cruft is left but it's very little now.

   - There is still some clamping of return values for .get() going on,
     but we now return sane values in the vast majority of drivers and
     the errorpath is sanitized.  Some patches for powerpc, blackfin and
     unicore still drop in.

   - We continue to switch the ARM, MIPS, blackfin, m68k local GPIO
     implementations to use gpiochip_add_data() and cut down on code
     lines.

   - MPC8xxx is converted to use the generic GPIO helpers.

   - ATH79 is converted to use the generic GPIO helpers.

  New drivers:

   - WinSystems WS16C48

   - Acces 104-DIO-48E

   - F81866 (a F7188x variant)

   - Qoric (a MPC8xxx variant)

   - TS-4800

   - SPI serializers (pisosr): simple 74xx shift registers connected to
     SPI to obtain a dirt-cheap output-only GPIO expander.

   - Texas Instruments TPIC2810

   - Texas Instruments TPS65218

   - Texas Instruments TPS65912

   - X-Gene (ARM64) standby GPIO controller"

* tag 'gpio-v4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (194 commits)
  Revert "Share upstreaming patches"
  gpio: mcp23s08: Fix clearing of interrupt.
  gpiolib: Fix comment referring to gpio_*() in gpiod_*()
  gpio: pca953x: Fix pca953x_gpio_set_multiple() on 64-bit
  gpio: xgene: Fix kconfig for standby GIPO contoller
  gpio: Add generic serializer DT binding
  gpio: uapi: use 0xB4 as ioctl() major
  gpio: tps65912: fix bad merge
  Revert "gpio: lp3943: Drop pin_used and lp3943_gpio_request/lp3943_gpio_free"
  gpio: omap: drop dev field from gpio_bank structure
  gpio: mpc8xxx: Slightly update the code for better readability
  gpio: mpc8xxx: Remove *read_reg and *write_reg from struct mpc8xxx_gpio_chip
  gpio: mpc8xxx: Fixup setting gpio direction output
  gpio: mcp23s08: Add support for mcp23s18
  dt-bindings: gpio: altera: Fix altr,interrupt-type property
  gpio: add driver for MEN 16Z127 GPIO controller
  gpio: lp3943: Drop pin_used and lp3943_gpio_request/lp3943_gpio_free
  gpio: timberdale: Switch to devm_ioremap_resource()
  gpio: ts4800: Add IMX51 dependency
  gpiolib: rewrite gpiodev_add_to_list
  ...
2016-03-17 21:05:32 -07:00
Linus Torvalds 710d60cbf1 Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull cpu hotplug updates from Thomas Gleixner:
 "This is the first part of the ongoing cpu hotplug rework:

   - Initial implementation of the state machine

   - Runs all online and prepare down callbacks on the plugged cpu and
     not on some random processor

   - Replaces busy loop waiting with completions

   - Adds tracepoints so the states can be followed"

More detailed commentary on this work from an earlier email:
 "What's wrong with the current cpu hotplug infrastructure?

   - Asymmetry

     The hotplug notifier mechanism is asymmetric versus the bringup and
     teardown.  This is mostly caused by the notifier mechanism.

   - Largely undocumented dependencies

     While some notifiers use explicitely defined notifier priorities,
     we have quite some notifiers which use numerical priorities to
     express dependencies without any documentation why.

   - Control processor driven

     Most of the bringup/teardown of a cpu is driven by a control
     processor.  While it is understandable, that preperatory steps,
     like idle thread creation, memory allocation for and initialization
     of essential facilities needs to be done before a cpu can boot,
     there is no reason why everything else must run on a control
     processor.  Before this patch series, bringup looks like this:

       Control CPU                     Booting CPU

       do preparatory steps
       kick cpu into life

                                       do low level init

       sync with booting cpu           sync with control cpu

       bring the rest up

   - All or nothing approach

     There is no way to do partial bringups.  That's something which is
     really desired because we waste e.g.  at boot substantial amount of
     time just busy waiting that the cpu comes to life.  That's stupid
     as we could very well do preparatory steps and the initial IPI for
     other cpus and then go back and do the necessary low level
     synchronization with the freshly booted cpu.

   - Minimal debuggability

     Due to the notifier based design, it's impossible to switch between
     two stages of the bringup/teardown back and forth in order to test
     the correctness.  So in many hotplug notifiers the cancel
     mechanisms are either not existant or completely untested.

   - Notifier [un]registering is tedious

     To [un]register notifiers we need to protect against hotplug at
     every callsite.  There is no mechanism that bringup/teardown
     callbacks are issued on the online cpus, so every caller needs to
     do it itself.  That also includes error rollback.

  What's the new design?

     The base of the new design is a symmetric state machine, where both
     the control processor and the booting/dying cpu execute a well
     defined set of states.  Each state is symmetric in the end, except
     for some well defined exceptions, and the bringup/teardown can be
     stopped and reversed at almost all states.

     So the bringup of a cpu will look like this in the future:

       Control CPU                     Booting CPU

       do preparatory steps
       kick cpu into life

                                       do low level init

       sync with booting cpu           sync with control cpu

                                       bring itself up

     The synchronization step does not require the control cpu to wait.
     That mechanism can be done asynchronously via a worker or some
     other mechanism.

     The teardown can be made very similar, so that the dying cpu cleans
     up and brings itself down.  Cleanups which need to be done after
     the cpu is gone, can be scheduled asynchronously as well.

  There is a long way to this, as we need to refactor the notion when a
  cpu is available.  Today we set the cpu online right after it comes
  out of the low level bringup, which is not really correct.

  The proper mechanism is to set it to available, i.e. cpu local
  threads, like softirqd, hotplug thread etc. can be scheduled on that
  cpu, and once it finished all booting steps, it's set to online, so
  general workloads can be scheduled on it.  The reverse happens on
  teardown.  First thing to do is to forbid scheduling of general
  workloads, then teardown all the per cpu resources and finally shut it
  off completely.

  This patch series implements the basic infrastructure for this at the
  core level.  This includes the following:

   - Basic state machine implementation with well defined states, so
     ordering and prioritization can be expressed.

   - Interfaces to [un]register state callbacks

     This invokes the bringup/teardown callback on all online cpus with
     the proper protection in place and [un]installs the callbacks in
     the state machine array.

     For callbacks which have no particular ordering requirement we have
     a dynamic state space, so that drivers don't have to register an
     explicit hotplug state.

     If a callback fails, the code automatically does a rollback to the
     previous state.

   - Sysfs interface to drive the state machine to a particular step.

     This is only partially functional today.  Full functionality and
     therefor testability will be achieved once we converted all
     existing hotplug notifiers over to the new scheme.

   - Run all CPU_ONLINE/DOWN_PREPARE notifiers on the booting/dying
     processor:

       Control CPU                     Booting CPU

       do preparatory steps
       kick cpu into life

                                       do low level init

       sync with booting cpu           sync with control cpu
       wait for boot
                                       bring itself up

                                       Signal completion to control cpu

     In a previous step of this work we've done a full tree mechanical
     conversion of all hotplug notifiers to the new scheme.  The balance
     is a net removal of about 4000 lines of code.

     This is not included in this series, as we decided to take a
     different approach.  Instead of mechanically converting everything
     over, we will do a proper overhaul of the usage sites one by one so
     they nicely fit into the symmetric callback scheme.

     I decided to do that after I looked at the ugliness of some of the
     converted sites and figured out that their hotplug mechanism is
     completely buggered anyway.  So there is no point to do a
     mechanical conversion first as we need to go through the usage
     sites one by one again in order to achieve a full symmetric and
     testable behaviour"

* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  cpu/hotplug: Document states better
  cpu/hotplug: Fix smpboot thread ordering
  cpu/hotplug: Remove redundant state check
  cpu/hotplug: Plug death reporting race
  rcu: Make CPU_DYING_IDLE an explicit call
  cpu/hotplug: Make wait for dead cpu completion based
  cpu/hotplug: Let upcoming cpu bring itself fully up
  arch/hotplug: Call into idle with a proper state
  cpu/hotplug: Move online calls to hotplugged cpu
  cpu/hotplug: Create hotplug threads
  cpu/hotplug: Split out the state walk into functions
  cpu/hotplug: Unpark smpboot threads from the state machine
  cpu/hotplug: Move scheduler cpu_online notifier to hotplug core
  cpu/hotplug: Implement setup/removal interface
  cpu/hotplug: Make target state writeable
  cpu/hotplug: Add sysfs state interface
  cpu/hotplug: Hand in target state to _cpu_up/down
  cpu/hotplug: Convert the hotplugged cpu work to a state machine
  cpu/hotplug: Convert to a state machine for the control processor
  cpu/hotplug: Add tracepoints
  ...
2016-03-15 13:50:29 -07:00
Linus Torvalds df2e37c814 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
 "The 4.6 pile of irq updates contains:

   - Support for IPI irqdomains to support proper integration of IPIs to
     and from coprocessors.  The first user of this new facility is
     MIPS.  The relevant MIPS patches come with the core to avoid merge
     ordering issues and have been acked by Ralf.

   - A new command line option to set the default interrupt affinity
     mask at boot time.

   - Support for some more new ARM and MIPS interrupt controllers:
     tango, alpine-msix and bcm6345-l1

   - Two small cleanups for x86/apic which we merged into irq/core to
     avoid yet another branch in x86 with two tiny commits.

   - The usual set of updates, cleanups in drivers/irqchip.  Mostly in
     the area of ARM-GIC, arada-37-xp and atmel chips.  Nothing
     outstanding here"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (56 commits)
  irqchip/irq-alpine-msi: Release the correct domain on error
  irqchip/mxs: Fix error check of of_io_request_and_map()
  irqchip/sunxi-nmi: Fix error check of of_io_request_and_map()
  genirq: Export IRQ functions for module use
  irqchip/gic/realview: Support more RealView DCC variants
  Documentation/bindings: Document the Alpine MSIX driver
  irqchip: Add the Alpine MSIX interrupt controller
  irqchip/gic-v3: Always return IRQ_SET_MASK_OK_DONE in gic_set_affinity
  irqchip/gic-v3-its: Mark its_init() and its children as __init
  irqchip/gic-v3: Remove gic_root_node variable from the ITS code
  irqchip/gic-v3: ACPI: Add redistributor support via GICC structures
  irqchip/gic-v3: Add ACPI support for GICv3/4 initialization
  irqchip/gic-v3: Refactor gic_of_init() for GICv3 driver
  x86/apic: Deinline _flat_send_IPI_mask, save ~150 bytes
  x86/apic: Deinline __default_send_IPI_*, save ~200 bytes
  dt-bindings: interrupt-controller: Add SoC-specific compatible string to Marvell ODMI
  irqchip/mips-gic: Add new DT property to reserve IPIs
  MIPS: Delete smp-gic.c
  MIPS: Make smp CMP, CPS and MT use the new generic IPI functions
  MIPS: Add generic SMP IPI support
  ...
2016-03-15 12:48:48 -07:00
Linus Torvalds d37a14bb5f Merge branch 'core-resources-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull ram resource handling changes from Ingo Molnar:
 "Core kernel resource handling changes to support NVDIMM error
  injection.

  This tree introduces a new I/O resource type, IORESOURCE_SYSTEM_RAM,
  for System RAM while keeping the current IORESOURCE_MEM type bit set
  for all memory-mapped ranges (including System RAM) for backward
  compatibility.

  With this resource flag it no longer takes a strcmp() loop through the
  resource tree to find "System RAM" resources.

  The new resource type is then used to extend ACPI/APEI error injection
  facility to also support NVDIMM"

* 'core-resources-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ACPI/EINJ: Allow memory error injection to NVDIMM
  resource: Kill walk_iomem_res()
  x86/kexec: Remove walk_iomem_res() call with GART type
  x86, kexec, nvdimm: Use walk_iomem_res_desc() for iomem search
  resource: Add walk_iomem_res_desc()
  memremap: Change region_intersects() to take @flags and @desc
  arm/samsung: Change s3c_pm_run_res() to use System RAM type
  resource: Change walk_system_ram() to use System RAM type
  drivers: Initialize resource entry to zero
  xen, mm: Set IORESOURCE_SYSTEM_RAM to System RAM
  kexec: Set IORESOURCE_SYSTEM_RAM for System RAM
  arch: Set IORESOURCE_SYSTEM_RAM flag for System RAM
  ia64: Set System RAM type and descriptor
  x86/e820: Set System RAM type and descriptor
  resource: Add I/O resource descriptor
  resource: Handle resource flags properly
  resource: Add System RAM resource type
2016-03-14 15:15:51 -07:00
James Hogan d825c06bfe MIPS: smp.c: Fix uninitialised temp_foreign_map
When calculate_cpu_foreign_map() recalculates the cpu_foreign_map
cpumask it uses the local variable temp_foreign_map without initialising
it to zero. Since the calculation only ever sets bits in this cpumask
any existing bits at that memory location will remain set and find their
way into cpu_foreign_map too. This could potentially lead to cache
operations suboptimally doing smp calls to multiple VPEs in the same
core, even though the VPEs share primary caches.

Therefore initialise temp_foreign_map using cpumask_clear() before use.

Fixes: cccf34e941 ("MIPS: c-r4k: Fix cache flushing for MT cores")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12759/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-03-13 10:59:19 +01:00
Ingo Molnar fe36d8912c Merge branch 'linus' into irq/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-08 12:26:07 +01:00
Maciej W. Rozycki e723e3f7f9 MIPS: traps: Fix SIGFPE information leak from `do_ov' and `do_trap_or_bp'
Avoid sending a partially initialised `siginfo_t' structure along SIGFPE
signals issued from `do_ov' and `do_trap_or_bp', leading to information
leaking from the kernel stack.

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-03-04 22:52:32 +01:00
Ingo Molnar bc94b99636 Linux 4.5-rc6
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Merge tag 'v4.5-rc6' into core/resources, to resolve conflict

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-04 12:12:08 +01:00
Thomas Gleixner fc6d73d674 arch/hotplug: Call into idle with a proper state
Let the non boot cpus call into idle with the corresponding hotplug state, so
the hotplug core can handle the further bringup. That's a first step to
convert the boot side of the hotplugged cpus to do all the synchronization
with the other side through the state machine. For now it'll only start the
hotplug thread and kick the full bringup of the cpu.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: Rik van Riel <riel@redhat.com>
Cc: Rafael Wysocki <rafael.j.wysocki@intel.com>
Cc: "Srivatsa S. Bhat" <srivatsa@mit.edu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: http://lkml.kernel.org/r/20160226182341.614102639@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-03-01 20:36:57 +01:00
Daniel Sanders 51ff5d7767 MIPS: Avoid variant of .type unsupported by LLVM Assembler
The target independent parts of the LLVM Lexer considers 'fault@function'
to be a single token representing the 'fault' symbol with a 'function'
modifier. However, this is not the case in the .type directive where
'function' refers to STT_FUNC from the ELF standard.

Although GAS accepts it, '.type symbol@function' is an undocumented form of
this directive. The documentation specifies a comma between the symbol and
'@function'.

Signed-off-by: Scott Egerton <Scott.Egerton@imgtec.com>
Signed-off-by: Daniel Sanders <daniel.sanders@imgtec.com>
Reviewed-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12587/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-02-29 11:23:49 +01:00
Qais Yousef 7eb8c99db2 MIPS: Delete smp-gic.c
We now have a generic IPI layer that will use GIC automatically
if it's compiled in.

Signed-off-by: Qais Yousef <qais.yousef@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: <jason@lakedaemon.net>
Cc: <marc.zyngier@arm.com>
Cc: <jiang.liu@linux.intel.com>
Cc: <linux-mips@linux-mips.org>
Cc: <lisa.parratt@imgtec.com>
Cc: Qais Yousef <qsyousef@gmail.com>
Link: http://lkml.kernel.org/r/1449580830-23652-19-git-send-email-qais.yousef@imgtec.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-02-25 10:56:58 +01:00
Qais Yousef bb11cff327 MIPS: Make smp CMP, CPS and MT use the new generic IPI functions
This commit does several things to avoid breaking bisectability.

	1- Remove IPI init code from irqchip/mips-gic
	2- Implement the new irqchip->send_ipi() in irqchip/mips-gic
	3- Select GENERIC_IRQ_IPI Kconfig symbol for MIPS_GIC
	4- Change MIPS SMP to use the generic IPI implementation

Only the SMP variants that use GIC were converted as it's the only irqchip that
will have the support for generic IPI for now.

Signed-off-by: Qais Yousef <qais.yousef@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: <jason@lakedaemon.net>
Cc: <marc.zyngier@arm.com>
Cc: <jiang.liu@linux.intel.com>
Cc: <linux-mips@linux-mips.org>
Cc: <lisa.parratt@imgtec.com>
Cc: Qais Yousef <qsyousef@gmail.com>
Link: http://lkml.kernel.org/r/1449580830-23652-18-git-send-email-qais.yousef@imgtec.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-02-25 10:56:58 +01:00
Qais Yousef fbde2d7d82 MIPS: Add generic SMP IPI support
Use the new generic IPI layer to provide generic SMP IPI support if the irqchip
supports it.

Signed-off-by: Qais Yousef <qais.yousef@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: <jason@lakedaemon.net>
Cc: <marc.zyngier@arm.com>
Cc: <jiang.liu@linux.intel.com>
Cc: <linux-mips@linux-mips.org>
Cc: <lisa.parratt@imgtec.com>
Cc: Qais Yousef <qsyousef@gmail.com>
Link: http://lkml.kernel.org/r/1449580830-23652-17-git-send-email-qais.yousef@imgtec.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-02-25 10:56:58 +01:00
Linus Walleij d98312f774 MIPS: txx9: switch to gpiochip_add_data()
We're planning to remove the gpiochip_add() function to swith
to gpiochip_add_data() with NULL for data argument.

Cc: linux-mips@linux-mips.org
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-19 09:51:44 +01:00
Daniel Wagner f4d3d50419 mips: Differentiate between 32 and 64 bit ELF header
Depending on the configuration either the 32 or 64 bit version of
elf_check_arch() is defined. parse_crash_elf{32|64}_headers() does
some basic verification of the ELF header via
vmcore_elf{32|64}_check_arch() which happen to map to elf_check_arch().
Since the implementation 32 and 64 bit version of elf_check_arch()
differ, we use the wrong type:

   In file included from include/linux/elf.h:4:0,
                    from fs/proc/vmcore.c:13:
   fs/proc/vmcore.c: In function 'parse_crash_elf64_headers':
>> arch/mips/include/asm/elf.h:228:23: error: initialization from incompatible pointer type [-Werror=incompatible-pointer-types]
     struct elfhdr *__h = (hdr);     \
                          ^
   include/linux/crash_dump.h:41:37: note: in expansion of macro 'elf_check_arch'
    #define vmcore_elf64_check_arch(x) (elf_check_arch(x) || vmcore_elf_check_arch_cross(x))
                                        ^
   fs/proc/vmcore.c:1015:4: note: in expansion of macro 'vmcore_elf64_check_arch'
      !vmcore_elf64_check_arch(&ehdr) ||
       ^

Therefore, we rather define vmcore_elf{32|64}_check_arch() as a
basic machine check and use it also in binfm_elf?32.c as well.

Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Suggested-by: Maciej W. Rozycki <macro@imgtec.com>
Reviewed-by: Maciej W. Rozycki <macro@imgtec.com>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12529/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-02-11 11:38:22 +01:00
Paul Burton 3af5a67c86 MIPS: Fix early CM probing
Commit c014d164f2 ("MIPS: Add platform callback before initializing
the L2 cache") added a platform_early_l2_init function in order to allow
platforms to probe for the CM before L2 initialisation is performed, so
that CM GCRs are available to mips_sc_probe.

That commit actually fails to do anything useful, since it checks
mips_cm_revision to determine whether it should call mips_cm_probe but
the result of mips_cm_revision will always be 0 until mips_cm_probe has
been called. Thus the "early" mips_cm_probe call never occurs.

Fix this & drop the useless weak platform_early_l2_init function by
simply calling mips_cm_probe from setup_arch. For platforms that don't
select CONFIG_MIPS_CM this will be a no-op, and for those that do it
removes the requirement for them to call mips_cm_probe manually
(although doing so isn't harmful for now).

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Aaro Koskinen <aaro.koskinen@nokia.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Jaedon Shin <jaedon.shin@gmail.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12475/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-02-09 17:18:31 +01:00
Ralf Baechle e6c058f9b2 MIPS: Wire up copy_file_range syscall.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-02-05 17:15:42 +01:00
Maciej W. Rozycki 7aa7047100 MIPS: traps.c: Correct microMIPS RDHWR emulation
Fix the code to fetch and decode the whole 32-bit instruction.  This
only really matters with the `noulri' kernel parameter as all microMIPS
processors are supposed to have all the hardware registers we support.

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12281/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-02-02 02:16:29 +01:00
Maciej W. Rozycki 10f6d99f0f MIPS: traps.c: Don't emulate RDHWR in the CpU #0 exception handler
In the regular MIPS instruction set RDHWR is encoded with the SPECIAL3
(011111) major opcode.  Therefore it cannot trigger the CpU (Coprocessor
Unusable) exception, and certainly not for coprocessor 0, as the opcode
does not overlap with any of the older ISA reservations, i.e. LWC0
(110000), SWC0 (111000), LDC0 (110100) or SDC0 (111100).  The closest
match might be SDC3 (111111), possibly causing a CpU #3 exception,
however our code does not handle it anyway.  A quick check with a MIPS I
and a MIPS III processor:

CPU0 revision is: 00000220 (R3000)
CPU0 revision is: 00000440 (R4400SC)

indeed indicates that the RI (Reserved Instruction) exception is
triggered.  It's only LL and SC that require emulation in the CpU #0
exception handler as they reuse the LWC0 and SWC0 opcodes respectively.

In the microMIPS instruction set RDHWR is mandatory and triggering the
RI exception is required on unimplemented or disabled register accesses.
Therefore emulating the microMIPS instruction in the CpU #0 exception
handler is not required either.

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12280/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-02-02 02:16:11 +01:00
James Hogan 76e5846d3b MIPS: Properly disable FPU in start_thread()
start_thread() (called for execve(2)) clears the TIF_USEDFPU flag
without atomically disabling the FPU. With a preemptive kernel, an
unfortunately timed preemption after this could result in another
task (or KVM guest) being scheduled in with the FPU still enabled, since
lose_fpu_inatomic() only turns it off if TIF_USEDFPU is set.

Use lose_fpu(0) instead of the separate FPU / MSA management, which
should do the right thing (drop FPU properly and atomically without
saving state) and will be more future proof.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12302/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-02-01 23:36:03 +01:00
Toshi Kani 35d98e93fe arch: Set IORESOURCE_SYSTEM_RAM flag for System RAM
Set IORESOURCE_SYSTEM_RAM in flags of resource ranges with
"System RAM", "Kernel code", "Kernel data", and "Kernel bss".

Note that:

 - IORESOURCE_SYSRAM (i.e. modifier bit) is set in flags when
   IORESOURCE_MEM is already set. IORESOURCE_SYSTEM_RAM is defined
   as (IORESOURCE_MEM|IORESOURCE_SYSRAM).

 - Some archs do not set 'flags' for children nodes, such as
   "Kernel code".  This patch does not change 'flags' in this
   case.

Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mips@linux-mips.org
Cc: linux-mm <linux-mm@kvack.org>
Cc: linux-parisc@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: sparclinux@vger.kernel.org
Link: http://lkml.kernel.org/r/1453841853-11383-7-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-30 09:49:57 +01:00
Linus Torvalds e2464688b5 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 for 4.5 plus some 4.4 fixes.

  The executive summary:

   - ATH79 platform improvments, use DT bindings for the ATH79 USB PHY.
   - Avoid useless rebuilds for zboot.
   - jz4780: Add NEMC, BCH and NAND device tree nodes
   - Initial support for the MicroChip's DT platform.  As all the device
     drivers are missing this is still of limited use.
   - Some Loongson3 cleanups.
   - The unavoidable whitespace polishing.
   - Reduce clock skew when synchronizing the CPU cycle counters on CPU
     startup.
   - Add MIPS R6 fixes.
   - Lots of cleanups across arch/mips as fallout from KVM.
   - Lots of minor fixes and changes for IEEE 754-2008 support to the
     FPU emulator / fp-assist software.
   - Minor Ralink, BCM47xx and bcm963xx platform support improvments.
   - Support SMP on BCM63168"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (84 commits)
  MIPS: zboot: Add support for serial debug using the PROM
  MIPS: zboot: Avoid useless rebuilds
  MIPS: BMIPS: Enable ARCH_WANT_OPTIONAL_GPIOLIB
  MIPS: bcm63xx: nvram: Remove unused bcm63xx_nvram_get_psi_size() function
  MIPS: bcm963xx: Update bcm_tag field image_sequence
  MIPS: bcm963xx: Move extended flash address to bcm_tag header file
  MIPS: bcm963xx: Move Broadcom BCM963xx image tag data structure
  MIPS: bcm63xx: nvram: Use nvram structure definition from header file
  MIPS: bcm963xx: Add Broadcom BCM963xx board nvram data structure
  MAINTAINERS: Add KVM for MIPS entry
  MIPS: KVM: Add missing newline to kvm_err()
  MIPS: Move KVM specific opcodes into asm/inst.h
  MIPS: KVM: Use cacheops.h definitions
  MIPS: Break down cacheops.h definitions
  MIPS: Use EXCCODE_ constants with set_except_vector()
  MIPS: Update trap codes
  MIPS: Move Cause.ExcCode trap codes to mipsregs.h
  MIPS: KVM: Make kvm_mips_{init,exit}() static
  MIPS: KVM: Refactor added offsetof()s
  MIPS: KVM: Convert EXPORT_SYMBOL to _GPL
  ...
2016-01-24 12:50:56 -08:00
Ralf Baechle 07d17f0969 Merge branch '4.4-fixes' into mips-for-linux-next 2016-01-24 04:14:40 +01:00
James Hogan 1b505defe0 MIPS: Use EXCCODE_ constants with set_except_vector()
The first argument to set_except_vector is the ExcCode, which we now
have definitions for. Lets make use of them.

Signed-off-by: James Hogan <james.hogan@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
Patchwork: https://patchwork.linux-mips.org/patch/11894/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-01-24 03:28:21 +01:00
James Hogan 555fae60b2 MIPS: ptrace: Drop cp0_tcstatus from regoffset_table[]
The cp0_tcstatus member of struct pt_regs was removed along with the
rest of SMTC in v3.16, commit b633648c5a ("MIPS: MT: Remove SMTC
support"), however recent uprobes support in v4.3 added back a reference
to it in the regoffset_table[] in ptrace.c. Remove it.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Fixes: 40e084a506 ("MIPS: Add uprobes support.")
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11920/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-01-24 02:24:24 +01:00
Linus Walleij 6ea6b7faf0 MIPS: TXx9: Be sure to clamp return value
As we want gpio_chip .get() calls to be able to return negative
error codes and propagate to drivers, we need to go over all
drivers and make sure their return values are clamped to [0,1].
We do this by using the ret = !!(val) design pattern.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: linux-mips@linux-mips.org
Cc: linux-gpio@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11923/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-01-24 02:22:14 +01:00
Jaedon Shin 2549cc967e MIPS: Fix macro typo
Change the CONFIG_MIPS_CMDLINE_EXTEND to CONFIG_MIPS_CMDLINE_DTB_EXTEND
to resolve the EXTEND_WITH_PROM macro.

Signed-off-by: Jaedon Shin <jaedon.shin@gmail.com>
Fixes: 2024972ef5 ("MIPS: Make the kernel arguments from dtb available")
Reviewed-by: Alexander Sverdlin <alexander.svedlin@gmail.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Aaro Koskinen <aaro.koskinen@nokia.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11909/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-01-24 02:12:25 +01:00
Matt Redfearn 497e803ebf MIPS: smp-cps: Ensure secondary cores start with EVA disabled
The kernel currently assumes that a core will start up in legacy mode
using the exception base provided through the CM GCR registers. If a
core has been configured in hardware to start in EVA mode, these
assumptions will fail.

This patch ensures that secondary cores are initialized to meet these
assumptions.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11907/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-01-24 02:09:53 +01:00
Huacai Chen db0dbd57d5 MIPS: sync-r4k: reduce skew while synchronization
While synchronization, count register will go backwards for the master.
If synchronise_count_master() runs before synchronise_count_slave(),
skew becomes even more. The skew is very harmful for CPU hotplug (CPU0
do synchronization with CPU1, then CPU0 do synchronization with CPU2
and CPU0's count goes backwards, so it will be out of sync with CPU1).

After the commit cf9bfe55f2 (MIPS: Synchronize MIPS count one
CPU at a time), we needn't evaluate count_reference at the beginning of
synchronise_count_master() any more. Thus, we evaluate the initcount (It
seems like count_reference is redundant) in the 2nd loop. Since we write
the count register in the last loop, we don't need additional barriers
(the existing memory barriers are enough).

Moreover, I think we loop 3 times is enough to get a primed instruction
cache, this can also get less skew than looping 5 times.

Comments are also updated in this patch.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
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/12163/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-01-24 01:31:51 +01:00
Maciej W. Rozycki 503943e0e5 MIPS: Add IEEE Std 754 conformance mode selection
Add an `ieee754=' kernel parameter to control IEEE Std 754 conformance
mode.

Use separate flags copied from the respective CPU feature flags, and
adjusted according to the conformance mode selected, to make binaries
requesting individual NaN encoding modes accepted or rejected as needed.
Update the initial setting for FCSR and, in the full FPU emulation mode,
its read-only mask accordingly.  Accept the mode selection requested for
legacy processors as well.

As with the EF_MIPS_NAN2008 ELF file header flag adjust both ABS2008 and
NAN2008 bits at the same time, to match the choice made for hardware
currently implemented.

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Fortune <Matthew.Fortune@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11481/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-01-20 00:39:20 +01:00
Maciej W. Rozycki 93adeaf6da MIPS: Determine the presence of IEEE Std 754-2008 features
Determine the presence of and the amount of control available over IEEE
Std 754-2008 features.

In the case of a hardware FPU being used examine the FIR register for
the presence of the HAS2008 bit and then the FCSR register for the
writability of the ABS2008 and NAN2008 bits and the hardwired state of
each of these bits if read-only.  Update the initial FCSR contents used
for threads and the FCSR writability mask accordingly.

For full FPU emulation and MIPS32 or MIPS64 processors make the FCSR
ABS2008 and NAN2008 bits writable.

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Fortune <Matthew.Fortune@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11480/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-01-20 00:39:20 +01:00
Maciej W. Rozycki 2b5e869ecf MIPS: ELF: Interpret the NAN2008 file header flag
Handle the EF_MIPS_NAN2008 ELF file header flag and refuse execution
where there is no support in the FPU for the NaN encoding mode requested
by a binary invoked.  Ensure that the setting of the bit in the binary
matches one in any intepreter used.  Set the thread's initial FCSR
contents according to the value of the EF_MIPS_NAN2008.

Set the values of the FCSR ABS2008 and NAN2008 bits both to the same
value if possible, to take the approach taken with existing FPU hardware
into account.  As of now all implementations have both bits hardwired to
the same value, that is both are fixed at 0 or both are fixed at 1, even
though the architecture allows for implementations where the amount of
control implemented with each of these two individual bits is
independent of each other.

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Fortune <Matthew.Fortune@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11479/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-01-20 00:39:20 +01:00
Maciej W. Rozycki eb4bc076ff ELF: Also pass any interpreter's file header to `arch_check_elf'
Also pass any interpreter's file header to `arch_check_elf' so that any
architecture handler can have a look at it if needed.

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Matthew Fortune <Matthew.Fortune@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11478/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-01-20 00:39:20 +01:00
Maciej W. Rozycki 90d53a91fb MIPS: math-emu: Add IEEE Std 754-2008 NaN encoding emulation
Implement IEEE Std 754-2008 NaN encoding wired to the state of the
FCSR.NAN2008 bit.  Make the interpretation of the quiet bit in NaN data
as follows:

* in the legacy mode originally defined by the MIPS architecture the
  value of 1 denotes an sNaN whereas the value of 0 denotes a qNaN,

* in the 2008 mode introduced with revision 5 of the MIPS architecture
  the value of 0 denotes an sNaN whereas the value of 1 denotes a qNaN,
  following the definition of the preferred NaN encoding introduced with
  IEEE Std 754-2008.

In the 2008 mode, following the requirement of the said standard, quiet
an sNaN where needed by setting the quiet bit to 1 and leaving all the
NaN payload bits unchanged.

Update format conversion operations according to the rules set by IEEE
Std 754-2008 and the MIPS architecture.  Specifically:

* propagate NaN payload bits through conversions between floating-point
  formats such that as much information as possible is preserved and
  specifically a conversion from a narrower format to a wider format and
  then back to the original format does not change a qNaN payload in any
  way,

* conversions from a floating-point to an integer format where the
  source is a NaN, infinity or a value that would convert to an integer
  outside the range of the result format produce, under the default
  exception handling, the respective values defined by the MIPS
  architecture.

In full FPU emulation set the FIR.HAS2008 bit to 1, however do not make
any further FCSR bits writable.

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Fortune <Matthew.Fortune@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11477/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-01-20 00:39:20 +01:00
Maciej W. Rozycki 9519ef37a4 MIPS: Define the legacy-NaN and 2008-NaN features
Allocate CPU option bits and define macros for the legacy-NaN and
2008-NaN IEEE Std 754 MIPS architecture features.  Unconditionally mark
the legacy-NaN feature as present across hardware and emulated
floating-point configurations.

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Fortune <Matthew.Fortune@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11475/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-01-20 00:39:20 +01:00