MIPS: Rework smt cmdline parameters

Provide a generic smt parameters interface aligned with s390
to allow users to limit smt usage and threads per core.

It replaced previous undocumented "nothreads

MIPS: Rework smt cmdline parameters

Provide a generic smt parameters interface aligned with s390
to allow users to limit smt usage and threads per core.

It replaced previous undocumented "nothreads" parameter for
smp-cps which is ambiguous and does not cover smp-mt.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

show more ...

treewide: Trace IPIs sent via smp_send_reschedule()

To be able to trace invocations of smp_send_reschedule(), rename the
arch-specific definitions of it to arch_smp_send_reschedule() and wrap it
int

treewide: Trace IPIs sent via smp_send_reschedule()

To be able to trace invocations of smp_send_reschedule(), rename the
arch-specific definitions of it to arch_smp_send_reschedule() and wrap it
into an smp_send_reschedule() that contains a tracepoint.

Changes to include the declaration of the tracepoint were driven by the
following coccinelle script:

@func_use@
@@
smp_send_reschedule(...);

@include@
@@
#include <trace/events/ipi.h>

@no_include depends on func_use && !include@
@@
#include <...>
+
+ #include <trace/events/ipi.h>

[csky bits]
[riscv bits]
Signed-off-by: Valentin Schneider <vschneid@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Guo Ren <guoren@kernel.org>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Link: https://lore.kernel.org/r/20230307143558.294354-6-vschneid@redhat.com

show more ...

mips/cpu: Mark play_dead() __noreturn

play_dead() doesn't return. Annotate it as such. By extension this
also makes arch_cpu_idle_dead() noreturn.

Acked-by: Florian Fainelli <f.fainelli@gmail.com

mips/cpu: Mark play_dead() __noreturn

play_dead() doesn't return. Annotate it as such. By extension this
also makes arch_cpu_idle_dead() noreturn.

Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Link: https://lore.kernel.org/r/2897b51a9b8beb5b594fe66fb1d3a479ddd2a0e2.1676358308.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>

show more ...

MIPS: arch_send_call_function_single_ipi() calling conventions change

Use mp_ops->send_ipi_single() instead of mp_ops->send_ipi_mask() in
arch_send_call_function_single_ipi(). send_ipi_single() can

MIPS: arch_send_call_function_single_ipi() calling conventions change

Use mp_ops->send_ipi_single() instead of mp_ops->send_ipi_mask() in
arch_send_call_function_single_ipi(). send_ipi_single() can send
IPI signal to a special cpu more efficiently.

Signed-off-by: Liangliang Huang <huangll@lemote.com>
Reviewed-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

show more ...

MIPS: kexec: Make a framework for both jumping and halting on nonboot CPUs

The existing implementation lets machine_kexec() CPU jump to reboot code
buffer, whereas other CPUs to relocated_kexec_smp_

MIPS: kexec: Make a framework for both jumping and halting on nonboot CPUs

The existing implementation lets machine_kexec() CPU jump to reboot code
buffer, whereas other CPUs to relocated_kexec_smp_wait. The natural way to
bring up an SMP new kernel would be to let CPU0 do it while others being
halted. For those failing to do so, fall back to the jumping method.

Signed-off-by: Dengcheng Zhu <dzhu@wavecomp.com>
[paul.burton@mips.com: Guard kexec_nonboot_cpu_jump with CONFIG_SMP]
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/20570/
Cc: pburton@wavecomp.com
Cc: ralf@linux-mips.org
Cc: linux-mips@linux-mips.org
Cc: rachel.mozes@intel.com

show more ...

MIPS: VDSO: Prevent use of smp_processor_id()

VDSO code should not be using smp_processor_id(), since it is executed
in user mode.
Introduce a VDSO-specific path which will cause a compile-time
or l

MIPS: VDSO: Prevent use of smp_processor_id()

VDSO code should not be using smp_processor_id(), since it is executed
in user mode.
Introduce a VDSO-specific path which will cause a compile-time
or link-time error (depending upon support for __compiletime_error) if
the VDSO ever incorrectly attempts to use smp_processor_id().

[Matt Redfearn <matt.redfearn@imgtec.com>: Move before change to
smp_processor_id in series]

Signed-off-by: Paul Burton <paul.burton@mips.com>
Signed-off-by: Matt Redfearn <matt.redfearn@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/17932/
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@linux-mips.org

show more ...

MIPS: Allow __cpu_number_map to be larger than NR_CPUS

In systems where the CPU id space is sparse, this allows a smaller
NR_CPUS to be chosen, thus keeping internal data structures smaller.

Signed

MIPS: Allow __cpu_number_map to be larger than NR_CPUS

In systems where the CPU id space is sparse, this allows a smaller
NR_CPUS to be chosen, thus keeping internal data structures smaller.

Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: Carlos Munoz <cmunoz@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17388/
[jhogan@kernel.org: Add depends on SMP to fix
"warning: symbol value '' invalid for MIPS_NR_CPU_NR_MAP"]
Signed-off-by: James Hogan <jhogan@kernel.org>

show more ...

MIPS: SMP: Constify smp ops

smp_ops providers do not modify their ops structures, so they should be
made const for robustness. Since currently the MIPS kernel is not mapped
with memory protection, t

MIPS: SMP: Constify smp ops

smp_ops providers do not modify their ops structures, so they should be
made const for robustness. Since currently the MIPS kernel is not mapped
with memory protection, this does not in itself provide any security
benefit, but it still makes sense to make this change.

There are also slight code size efficincies from the structure being
made read-only, saving 128 bytes of kernel text on a
pistachio_defconfig.
Before:
text data bss dec hex filename
7187239 1772752 470224 9430215 8fe4c7 vmlinux
After:
text data bss dec hex filename
7187111 1772752 470224 9430087 8fe447 vmlinux

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Doug Ledford <dledford@redhat.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Joe Perches <joe@perches.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Steven J. Hill <steven.hill@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16784/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

show more ...

MIPS: SMP: move asmlinkage before return type

Make the code like the rest of the kernel.

Link: http://lkml.kernel.org/r/756d3fb543e981b9284e756fa27616725a354b28.1499284835.git.joe@perches.com
Signe

MIPS: SMP: move asmlinkage before return type

Make the code like the rest of the kernel.

Link: http://lkml.kernel.org/r/756d3fb543e981b9284e756fa27616725a354b28.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

MIPS: kexec: remove SMP_DUMP

SMP_DUMP has been added as a new IPI signal when kexec support was added
for Cavium Octeon CPUs ('commit 7aa1c8f47e7e ("MIPS: kdump: Add support")'.
However, the new sig

MIPS: kexec: remove SMP_DUMP

SMP_DUMP has been added as a new IPI signal when kexec support was added
for Cavium Octeon CPUs ('commit 7aa1c8f47e7e ("MIPS: kdump: Add support")'.
However, the new signal doesn't appear to ever have a proper handler
added (octeon_message_functions[] array has an empty handler for it),
and generic IPI handlers now trigger a BUG() on unhandled signal.

As the method is unused remove it completely and replace its only
invocation with a smp_call_function().

[ralf@linux-mips.org: Renumber SMP_ASK_C0COUNT to avoid numbering gaps.]

Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14630/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

show more ...

MIPS: SMP: Remove cpu_callin_map

The previous commit made cpu_callin_map redundant, since it is no longer
used to signal secondary CPUs starting, or going offline. Remove it now.

Signed-off-by: Mat

MIPS: SMP: Remove cpu_callin_map

The previous commit made cpu_callin_map redundant, since it is no longer
used to signal secondary CPUs starting, or going offline. Remove it now.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Qais Yousef <qsyousef@gmail.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Yang Shi <yang.shi@windriver.com>
Cc: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14503/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

show more ...

MIPS: smp.c: Introduce mechanism for freeing and allocating IPIs

For the MIPS remote processor implementation, we need additional IPIs to
talk to the remote processor. Since MIPS GIC reserves exactl

MIPS: smp.c: Introduce mechanism for freeing and allocating IPIs

For the MIPS remote processor implementation, we need additional IPIs to
talk to the remote processor. Since MIPS GIC reserves exactly the right
number of IPI IRQs required by Linux for the number of VPs in the
system, this is not possible without releasing some recources.

This commit introduces mips_smp_ipi_allocate() which allocates IPIs to a
given cpumask. It is called as normal with the cpu_possible_mask at
bootup to initialise IPIs to all CPUs. mips_smp_ipi_free() may then be
used to free IPIs to a subset of those CPUs so that their hardware
resources can be reused.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Lisa Parratt <Lisa.Parratt@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Qais Yousef <qsyousef@gmail.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-remoteproc@vger.kernel.org
Cc: lisa.parratt@imgtec.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14285/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

show more ...

MIPS: c-r4k: Exclude sibling CPUs in SMP calls

When performing SMP calls to foreign cores, exclude sibling CPUs from
the provided map, as we already handle the local core on the current
CPU. This pr

MIPS: c-r4k: Exclude sibling CPUs in SMP calls

When performing SMP calls to foreign cores, exclude sibling CPUs from
the provided map, as we already handle the local core on the current
CPU. This prevents an SMP call from for example core 0, VPE 1 to VPE 0
on the same core.

In the process the cpu_foreign_map cpumask is turned into an array of
cpumasks, so that each CPU has its own version of it which excludes
sibling CPUs. r4k_op_needs_ipi() is also updated to reflect that cache
management SMP calls are not needed when all CPUs are siblings (i.e.
there are no foreign CPUs according to the new cpu_foreign_map[]
semantics which exclude siblings).

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: Felix Fietkau <nbd@nbd.name>
Cc: Jayachandran C. <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13801/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

show more ...

MIPS: SMP: Update cpu_foreign_map on CPU disable

When a CPU is disabled via CPU hotplug, cpu_foreign_map is not updated.
This could result in cache management SMP calls being sent to offline
CPUs in

MIPS: SMP: Update cpu_foreign_map on CPU disable

When a CPU is disabled via CPU hotplug, cpu_foreign_map is not updated.
This could result in cache management SMP calls being sent to offline
CPUs instead of online siblings in the same core.

Add a call to calculate_cpu_foreign_map() in the various MIPS cpu
disable callbacks after set_cpu_online(). All cases are updated for
consistency and to keep cpu_foreign_map strictly up to date, not just
those which may support hardware multithreading.

Fixes: cccf34e9411c ("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: David Daney <david.daney@cavium.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Hongliang Tao <taohl@lemote.com>
Cc: Hua Yan <yanh@lemote.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13799/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

show more ...

MIPS: SMP: Don't increment irq_count multiple times for call function IPIs

The majority of SMP platforms handle their IPIs through do_IRQ()
which calls irq_{enter/exit}(). When a call function IPI i

MIPS: SMP: Don't increment irq_count multiple times for call function IPIs

The majority of SMP platforms handle their IPIs through do_IRQ()
which calls irq_{enter/exit}(). When a call function IPI is received,
smp_call_function_interrupt() is called which also calls
irq_{enter,exit}(), meaning irq_count is raised twice.

When tick broadcasting is used (which is implemented via a call
function IPI), this incorrectly causes all CPU idle time on the core
receiving broadcast ticks to be accounted as time spent servicing
IRQs, as account_process_tick() will account as such if irq_count is
greater than 1. This results in 100% CPU usage being reported on a
core which receives its ticks via broadcast.

This patch removes the SMP smp_call_function_interrupt() wrapper which
calls irq_{enter,exit}(). Platforms which handle their IPIs through
do_IRQ() now call generic_smp_call_function_interrupt() directly to
avoid incrementing irq_count a second time. Platforms which don't
(loongson, sgi-ip27, sibyte) call generic_smp_call_function_interrupt()
wrapped in irq_{enter,exit}().

Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10770/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

show more ...

MIPS: c-r4k: Fix cache flushing for MT cores

MT_SMP is not the only SMP option for MT cores. The MT_SMP option
allows more than one VPE per core to appear as a secondary CPU in the
system. Because o

MIPS: c-r4k: Fix cache flushing for MT cores

MT_SMP is not the only SMP option for MT cores. The MT_SMP option
allows more than one VPE per core to appear as a secondary CPU in the
system. Because of how CM works, it propagates the address-based
cache ops to the secondary cores but not the index-based ones.
Because of that, the code does not use IPIs to flush the L1 caches on
secondary cores because the CM would have done that already. However,
the CM functionality is independent of the type of SMP kernel so even in
non-MT kernels, IPIs are not necessary. As a result of which, we change
the conditional to depend on the CM presence. Moreover, since VPEs on
the same core share the same L1 caches, there is no need to send an
IPI on all of them so we calculate a suitable cpumask with only one
VPE per core.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: <stable@vger.kernel.org> # 3.15+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10654/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

show more ...

MIPS: SMP: Fix build error.

CC arch/mips/kernel/smp.o
arch/mips/kernel/smp.c: In function ‘start_secondary’:
arch/mips/kernel/smp.c:149:2: error: passing argument 2 of ‘cpumask_set_cpu’ disca

MIPS: SMP: Fix build error.

CC arch/mips/kernel/smp.o
arch/mips/kernel/smp.c: In function ‘start_secondary’:
arch/mips/kernel/smp.c:149:2: error: passing argument 2 of ‘cpumask_set_cpu’ discards ‘volatile’ qualifier from pointer target type [-Werror]
cpumask_set_cpu(cpu, &cpu_callin_map);
^
In file included from ./arch/mips/include/asm/processor.h:14:0,
from ./arch/mips/include/asm/thread_info.h:15,
from include/linux/thread_info.h:54,
from include/asm-generic/preempt.h:4,
from arch/mips/include/generated/asm/preempt.h:1,
from include/linux/preempt.h:18,
from include/linux/interrupt.h:8,
from arch/mips/kernel/smp.c:24:
include/linux/cpumask.h:272:91: note: expected ‘struct cpumask *’ but argument is of type ‘volatile struct cpumask_t *’
static inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
^
arch/mips/kernel/smp.c: In function ‘smp_prepare_boot_cpu’:
arch/mips/kernel/smp.c:211:2: error: passing argument 2 of ‘cpumask_set_cpu’ discards ‘volatile’ qualifier from pointer target type [-Werror]
cpumask_set_cpu(0, &cpu_callin_map);
^
In file included from ./arch/mips/include/asm/processor.h:14:0,
from ./arch/mips/include/asm/thread_info.h:15,
from include/linux/thread_info.h:54,
from include/asm-generic/preempt.h:4,
from arch/mips/include/generated/asm/preempt.h:1,
from include/linux/preempt.h:18,
from include/linux/interrupt.h:8,
from arch/mips/kernel/smp.c:24:
include/linux/cpumask.h:272:91: note: expected ‘struct cpumask *’ but argument is of type ‘volatile struct cpumask_t *’
static inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
^
arch/mips/kernel/smp.c: In function ‘__cpu_up’:
arch/mips/kernel/smp.c:221:10: error: passing argument 2 of ‘cpumask_test_cpu’ discards ‘volatile’ qualifier from pointer target type [-Werror]
while (!cpumask_test_cpu(cpu, &cpu_callin_map))
^
In file included from ./arch/mips/include/asm/processor.h:14:0,
from ./arch/mips/include/asm/thread_info.h:15,
from include/linux/thread_info.h:54,
from include/asm-generic/preempt.h:4,
from arch/mips/include/generated/asm/preempt.h:1,
from include/linux/preempt.h:18,
from include/linux/interrupt.h:8,
from arch/mips/kernel/smp.c:24:
include/linux/cpumask.h:294:90: note: expected ‘const struct cpumask *’ but argument is of type ‘volatile struct cpumask_t *’
static inline int cpumask_test_cpu(int cpu, const struct cpumask *cpumask)
^
cc1: all warnings being treated as errors
make[2]: *** [arch/mips/kernel/smp.o] Error 1
make[1]: *** [arch/mips/kernel] Error 2
make: *** [arch/mips] Error 2

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

show more ...

mips: fix obsolete cpumask_of_cpu usage.

Plus, it's weird.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

MIPS: Move CPU topology macros to topology.h

The correct position is topology.h, and this fix macros redefinition
problems for Netlogic.

[ralf@linux-mips.org: Fix build - the original patch broke m

MIPS: Move CPU topology macros to topology.h

The correct position is topology.h, and this fix macros redefinition
problems for Netlogic.

[ralf@linux-mips.org: Fix build - the original patch broke most
configurations.]

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: Jayachandran C. <jchandra@broadcom.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/7575/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

show more ...

MIPS: Support CPU topology files in sysfs

This patch is prepared for Loongson's NUMA support, it offer meaningful
sysfs files such as physical_package_id, core_id, core_siblings and
thread_siblings

MIPS: Support CPU topology files in sysfs

This patch is prepared for Loongson's NUMA support, it offer meaningful
sysfs files such as physical_package_id, core_id, core_siblings and
thread_siblings in /sys/devices/system/cpu/cpu?/topology.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Reviewed-by: Andreas Herrmann <andreas.herrmann@caviumnetworks.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/7184/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

show more ...

MIPS: introduce cpu_coherent_mask

Add a mask of CPUs which are currently known to be operating coherently.
This is setup initially to be all present CPUs, but in a subsequent
patch CPUs in a MIPS Co

MIPS: introduce cpu_coherent_mask

Add a mask of CPUs which are currently known to be operating coherently.
This is setup initially to be all present CPUs, but in a subsequent
patch CPUs in a MIPS Coherent Processing System will be cleared in this
mask as they enter non-coherent idle states. This will be used in order
to determine when a CPU within a CPS system may need to be powered back
up, but may also be used in future to optimise away wakeups for cache
operations or TLB invalidations.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>

show more ...

MIPS: Loongson 3: Add CPU hotplug support

Tips of Loongson's CPU hotplug:
1, To fully shutdown a core in Loongson 3, the target core should go to
CKSEG1 and flush all L1 cache entries at first. T

MIPS: Loongson 3: Add CPU hotplug support

Tips of Loongson's CPU hotplug:
1, To fully shutdown a core in Loongson 3, the target core should go to
CKSEG1 and flush all L1 cache entries at first. Then, another core
(usually Core 0) can safely disable the clock of the target core. So
play_dead() call loongson3_play_dead() via CKSEG1 (both uncached and
unmmaped).
2, The default clocksource of Loongson is MIPS. Since clock source is a
global device, timekeeping need the CP0' Count registers of each core
be synchronous. Thus, when a core is up, we use a SMP_ASK_C0COUNT IPI
to ask Core-0's Count.

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/6639
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

show more ...

MIPS: Whitespace cleanup.

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-b

MIPS: Whitespace cleanup.

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>

show more ...

MIPS: kdump: Add support

[ralf@linux-mips.org: Original patch by Maxim Uvarov <muvarov@gmail.com>
with plenty of further shining, polishing, debugging and testing by me.]

Signed-off-by: Maxim Uvaro

MIPS: kdump: Add support

[ralf@linux-mips.org: Original patch by Maxim Uvarov <muvarov@gmail.com>
with plenty of further shining, polishing, debugging and testing by me.]

Signed-off-by: Maxim Uvarov <muvarov@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: kexec@lists.infradead.org
Cc: horms@verge.net.au
Patchwork: https://patchwork.linux-mips.org/patch/1025/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

show more ...

atomic: use <linux/atomic.h>

This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>

Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Er

atomic: use <linux/atomic.h>

This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>

Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...