In commit 8393c524a2 (MIPS: tlbex: Fix a missing statement for
HUGETLB), the TLB Refill handler was fixed so that non-OCTEON targets
would work properly with huge pages. The change was incorrect in that
it broke the OCTEON case.
The problem is shown here:
xxx0: df7a0000 ld k0,0(k1)
.
.
.
xxxc0: df610000 ld at,0(k1)
xxxc4: 335a0ff0 andi k0,k0,0xff0
xxxc8: e825ffcd bbit1 at,0x5,0x0
xxxcc: 003ad82d daddu k1,at,k0
.
.
.
In the non-octeon case there is a destructive test for the huge PTE
bit, and then at 0, $k0 is reloaded (that is what the 8393c524a2
patch added).
In the octeon case, we modify k1 in the branch delay slot, but we
never need k0 again, so the new load is not needed, but since k1 is
modified, if we do the load, we load from a garbage location and then
get a nested TLB Refill, which is seen in userspace as either SIGBUS
or SIGSEGV (depending on the garbage).
The real fix is to only do this reloading if it is needed, and never
where it is harmful.
Signed-off-by: David Daney <david.daney@cavium.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: stable@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8151/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Use the regular tlb_do_page_fault_0 (no write) handler to handle
the RI and XI exceptions. Also skip the RI/XI validation check
on TLB load handler since it's redundant when the CPU has
unique RI/XI exceptions.
Singed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7339/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The Hardware Page Table Walker aims to speed up TLB refill exceptions
by handling them in the hardware level instead of having a software
TLB refill handler. However, a TLB refill exception can still be
thrown in certain cases such as, synchronus exceptions, or address
translation or memory errors during the HTW operation. As a result of
which, HTW must not be considered a complete replacement for the TLB
refill software handler, but rather a fast-path for it.
For HTW to work, the PWBase register must contain the task's page
global directory address so the HTW will kick in on TLB refill
exceptions.
Due to HTW being a separate engine embedded deep in the CPU pipeline,
we need to restart the HTW everytime a PTE changes to avoid HTW
fetching a old entry from the page tables. It's also necessary to
restart the HTW on context switches to prevent it from fetching a
page from the previous process. Finally, since HTW is using the
entryhi register to write the translations to the TLB, it's necessary
to stop the HTW whenever the entryhi changes (eg for tlb probe
perations) and enable it back afterwards.
== Performance ==
The following trivial test was used to measure the performance of the
HTW. Using the same root filesystem, the following command was used
to measure the number of tlb refill handler executions with and
without (using 'nohtw' kernel parameter) HTW support. The kernel was
modified to use a scratch register as a counter for the TLB refill
exceptions.
find /usr -type f -exec ls -lh {} \;
HTW Enabled:
TLB refill exceptions: 12306
HTW Disabled:
TLB refill exceptions: 17805
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/7336/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit
Commit 1d40cfcd34
Author: Ralf Baechle <ralf@linux-mips.org>
Date: Fri Jul 15 15:23:23 2005 +0000
Avoid SMP cacheflushes. This is a minor optimization of startup but
will also avoid smp_call_function from doing stupid things when called
from a CPU that is not yet marked online.
missed an appropriate cache flush of TLB refill handler because that time it was
at fixed location CAC_BASE. After years the refill handler in EBASE vector
is not at that location and can be allocated in some another memory and needs
I-cache sync as other TLB exception vectors.
Besides that, the new function - local_flash_icache_range() was introduced
to avoid SMP cacheflushes.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: paul.gortmaker@windriver.com
Cc: jchandra@broadcom.com
Cc: linux-kernel@vger.kernel.org
Cc: david.daney@cavium.com
Patchwork: https://patchwork.linux-mips.org/patch/7312/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
In commit 2c8c53e28f (MIPS: Optimize TLB handlers for Octeon CPUs)
build_r4000_tlb_refill_handler() is modified. But it doesn't compatible
with the original code in HUGETLB case. Because there is a copy & paste
error and one line of code is missing. It is very easy to produce a bug
with LTP's hugemmap05 test.
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Binbin Zhou <zhoubb@lemote.com>
Cc: <stable@vger.kernel.org>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/7496/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
For para-virtualized guests running under KVM or other equivalent
hypervisor.
Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: Andreas Herrmann <andreas.herrmann@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: kvm@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7004/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The fast handler only supports 64-bit kernels.
Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: Andreas Herrmann <andreas.herrmann@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: kvm@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7010/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit f4ae17aa0f [MIPS: mm: Use scratch for
PGD when !CONFIG_MIPS_PGD_C0_CONTEXT] broke microMIPS kernel builds. This
patch refactors that code similar to what was done for the 'clear_page'
and 'copy_page' functions.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6744/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Basic Loongson-3 CPU support include CPU probing and TLB/cache
initializing.
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Hongliang Tao <taohl@lemote.com>
Signed-off-by: Hua Yan <yanh@lemote.com>
Tested-by: Alex Smith <alex.smith@imgtec.com>
Reviewed-by: Alex Smith <alex.smith@imgtec.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
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/6630
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
If current_cpu_type() is pre-defined in cpu-feature-overrides.h, This
may save about 10k for the compressed kernel image(vmlinuz).
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1901/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The M5150 core is a 32-bit MIPS RISC which implements the
MIPS Architecture Release-5 in a 5-stage pipeline.
In addition, it includes the MIPS Architecture Virtualization Module
that enables virtualization of operating systems,
which provides a scalable, trusted, and secure execution environment.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6596/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Add a CPU_P5600 case to various switch statements, doing the same thing
as for CPU_PROAPTIV.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6408/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The 1074K is a multiprocessing coherent processing system (CPS) based
on modified 74K cores. This patch makes the 1074K an actual unique
CPU type, instead of a 74K derivative, which it is not.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Reviewed-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6389/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>. Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6320/
The proAptiv Multiprocessing System is a power efficient multi-core
microprocessor for use in system-on-chip (SoC) applications.
The proAptiv Multiprocessing System combines a deep pipeline
with multi-issue out of order execution for improved computational
throughput. The proAptiv Multiprocessing System can contain one to
six MIPS32r3 proAptiv cores, system level coherence
manager with L2 cache, optional coherent I/O port, and optional
floating point unit.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6134/
Allow usage of scratch register for current pgd even when
MIPS_PGD_C0_CONTEXT is not configured. MIPS_PGD_C0_CONTEXT is set
for 64r2 platforms to indicate availability of Xcontext for saving
cpuid, thus freeing Context to be used for saving PGD. This option
was also tied to using a scratch register for storing PGD.
This commit will allow usage of scratch register to store the current
pgd if one can be allocated for the platform, even when
MIPS_PGD_C0_CONTEXT is not set. The cpuid will be kept in the CP0
Context register in this case.
The code to store the current pgd for the TLB miss handler is now
generated in all cases. When scratch register is available, the PGD
is also stored in the scratch register.
Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Patchwork: https://patchwork.linux-mips.org/patch/5906/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The definition of the CP0 register used to save the smp processor
id is repicated in many files, move them all to thread_info.h.
Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5708/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
o Move current_cpu_type() to a separate header file
o #ifdefing on supported CPU types lets modern GCC know that certain
code in callers may be discarded ideally turning current_cpu_type() into
a function returning a constant.
o Use current_cpu_type() rather than direct access to struct cpuinfo_mips.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5833/
Pull MIPS fixes from Ralf Baechle:
"MIPS fixes for 3.11. Half of then is for Netlogic the remainder
touches things across arch/mips.
Nothing really dramatic and by rc1 standards MIPS will be in fairly
good shape with this applied. Tested by building all MIPS defconfigs
of which with this pull request four platforms won't build. And yes,
it boots also on my favorite test systems"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
MIPS: kvm: Kconfig: Drop HAVE_KVM dependency from VIRTUALIZATION
MIPS: Octeon: Fix DT pruning bug with pip ports
MIPS: KVM: Mark KVM_GUEST (T&E KVM) as BROKEN_ON_SMP
MIPS: tlbex: fix broken build in v3.11-rc1
MIPS: Netlogic: Add XLP PIC irqdomain
MIPS: Netlogic: Fix USB block's coherent DMA mask
MIPS: tlbex: Fix typo in r3000 tlb store handler
MIPS: BMIPS: Fix thinko to release slave TP from reset
MIPS: Delete dead invocation of exception_exit().
Commit 6ba045f9fb (MIPS: Move generated code
to .text for microMIPS) deleted tlbmiss_handler_setup_pgd_array, but some
references were not converted. Fix that to enable building a MIPS kernel.
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: Jayachandran C. <jchandra@broadcom.com>
Acked-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5589/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
commit 6ba045f (MIPS: Move generated code to .text for microMIPS)
causes a panic at boot. The handler builder should test against
handle_tlbs_end, not handle_tlbs.
Signed-off-by: Tony Wu <tung7970@gmail.com>
Acked-by: Jayachandran C. <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5600/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
commit 3747069b25e419f6b51395f48127e9812abc3596 upstream.
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications. For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.
After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out. Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.
Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
and are flagged as __cpuinit -- so if we remove the __cpuinit from
the arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
related content into no-ops as early as possible, since that will get
rid of these warnings. In any case, they are temporary and harmless.
Here, we remove all the MIPS __cpuinit from C code and __CPUINIT
from asm files. MIPS is interesting in this respect, because there
are also uasm users hiding behind their own renamed versions of the
__cpuinit macros.
[1] https://lkml.org/lkml/2013/5/20/589
[ralf@linux-mips.org: Folded in Paul's followup fix.]
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5494/
Patchwork: https://patchwork.linux-mips.org/patch/5495/
Patchwork: https://patchwork.linux-mips.org/patch/5509/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Prepare of a next patch which will call tlbmiss_handler_setup_pgd on
microMIPS. MicroMIPS complains if the called code s not in the .text
section. To fix this we generate code into space reserved in
arch/mips/mm/tlb-funcs.S
While there, move the rest of the generated functions (handle_tlbl,
handle_tlbs, handle_tlbm) to the same file.
Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5542/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
When having enabled MIPS_PGD_C0_CONTEXT, trap_init() might call the
generated tlbmiss_handler_setup_pgd before it was committed to memory,
causing boot failures:
trap_init()
|- per_cpu_trap_init()
| |- TLBMISS_HANDLER_SETUP()
| |- tlbmiss_handler_setup_pgd()
|- flush_tlb_handlers()
To avoid this, move flush_tlb_handlers() into build_tlb_refill_handler()
right after they were generated. We can do this as the cache handling is
initialized just before creating the tlb handlers.
This issue was introduced in 3d8bfdd030
("MIPS: Use C0_KScratch (if present) to hold PGD pointer.").
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Jayachandran C <jchandra@broadcom.com>
Cc: David Daney <david.daney@cavium.com>
Patchwork: https://patchwork.linux-mips.org/patch/5539/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS R2 documents state that an execution hazard barrier is needed
after a TLBR before reading EntryLo.
Original patch by Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/5526/
The invalid value for scratch register is -1, so update the checks of
the form (scratch_reg > 0) to be (scratch_reg >= 0). This will fix
the case in Netlogic XLP where the scratch_reg can be 0.
Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5444/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
XLR/XLP COP0 scratch is register 22, sel 0-7. Add a function
c0_kscratch() which returns the scratch register for the platform,
and use the return value while generating TLB handlers.
Setup kscratch_mask to 0xf for XLR/XLP since the config4 register
does not exist. This allows the kernel to allocate scratch registers
0-3 if needed.
Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5445/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This reverts commit d532f3d267.
The original commit has several problems:
1) Doesn't work with 64-bit kernels.
2) Calls TLBMISS_HANDLER_SETUP() before the code is generated.
3) Calls TLBMISS_HANDLER_SETUP() twice in per_cpu_trap_init() when
only one call is needed.
[ralf@linux-mips.org: Also revert the bits of the ASID patch which were
hidden in the KVM merge.]
Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: "Steven J. Hill" <Steven.Hill@imgtec.com>
Cc: David Daney <david.daney@cavium.com>
Patchwork: https://patchwork.linux-mips.org/patch/5242/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
All exceptions must be taken in microMIPS mode, never in classic
MIPS mode or the kernel falls apart. A few NOP instructions are
used to maintain the correct alignment of microMIPS versions of
the exception vectors.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Changes for pure microMIPS cores to dynamically determine the ASID
size at boot time.
Includes bug fix https://patchwork.linux-mips.org/patch/5230/
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Original patch by Ralf Baechle and removed by Harold Koerfgen
with commit f67e4ffc79905482c3b9b8c8dd65197bac7eb508. This
allows for more generic kernels since the size of the ASID
and corresponding masks can be determined at run-time. This
patch is also required for the new Aptiv cores and has been
tested on Malta and Malta Aptiv platforms.
[ralf@linux-mips.org: Added relevant part of fix
https://patchwork.linux-mips.org/patch/5213/]
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This and the next patch resolve memory corruption problems while CPU
hotplug. Without these patches, memory corruption can triggered easily
as below:
On a quad-core MIPS platform, use "spawn" of UnixBench-5.1.3 (http://
code.google.com/p/byte-unixbench/) and a CPU hotplug script like this
(hotplug.sh):
while true; do
echo 0 >/sys/devices/system/cpu/cpu1/online
echo 0 >/sys/devices/system/cpu/cpu2/online
echo 0 >/sys/devices/system/cpu/cpu3/online
sleep 1
echo 1 >/sys/devices/system/cpu/cpu1/online
echo 1 >/sys/devices/system/cpu/cpu2/online
echo 1 >/sys/devices/system/cpu/cpu3/online
sleep 1
done
Run "hotplug.sh" and then run "spawn 10000", spawn will get segfault
after a few minutes.
This patch:
Currently, clear_page()/copy_page() are generated by Micro-assembler
dynamically. But they are unavailable until uasm_resolve_relocs() has
finished because jump labels are illegal before that. Since these
functions are shared by every CPU, we only call build_clear_page()/
build_copy_page() only once at boot time. Without this patch, programs
will get random memory corruption (segmentation fault, bus error, etc.)
while CPU Hotplug (e.g. one CPU is using clear_page() while another is
generating it in cpu_cache_init()).
For similar reasons we modify build_tlb_refill_handler()'s invocation.
V2:
1, Rework the code to make CPU#0 can be online/offline.
2, Introduce cpu_has_local_ebase feature since some types of MIPS CPU
need a per-CPU tlb_refill_handler().
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Hongbing Hu <huhb@lemote.com>
Acked-by: David Daney <david.daney@cavium.com>
Patchwork: http://patchwork.linux-mips.org/patch/4994/
Acked-by: John Crispin <blogic@openwrt.org>
tlbmiss_handler_setup_pgd is run-time generated code and it was convenient
to pretend the symbol was an array in the generator but a function for
the users. LTO gcc won't tolerate this kind of lie anymore so solve the
problem through a cast and function pointer instead.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Having received another series of whitespace patches I decided to do this
once and for all rather than dealing with this kind of patches trickling
in forever.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
David Daney