mips, kexec: fix the incorrect ifdeffery and dependency of CONFIG_KEXEC

The select of KEXEC for CRASH_DUMP in kernel/Kconfig.kexec will be
dropped, then compiling errors will be triggered if below config items are
set:

===
CONFIG_CRASH_CORE=y
CONFIG_KEXEC_CORE=y
CONFIG_CRASH_DUMP=y
===

--------------------------------------------------------------------
mipsel-linux-ld: kernel/kexec_core.o: in function `kimage_free':
kernel/kexec_core.c:(.text+0x2200): undefined reference to `machine_kexec_cleanup'
mipsel-linux-ld: kernel/kexec_core.o: in function `__crash_kexec':
kernel/kexec_core.c:(.text+0x2480): undefined reference to `machine_crash_shutdown'
mipsel-linux-ld: kernel/kexec_core.c:(.text+0x2488): undefined reference to `machine_kexec'
mipsel-linux-ld: kernel/kexec_core.o: in function `kernel_kexec':
kernel/kexec_core.c:(.text+0x29b8): undefined reference to `machine_shutdown'
mipsel-linux-ld: kernel/kexec_core.c:(.text+0x29c0): undefined reference to `machine_kexec'
--------------------------------------------------------------------

Here, change the dependency of building kexec_core related object files,
and the ifdeffery in mips from CONFIG_KEXEC to CONFIG_KEXEC_CORE.

Link: https://lkml.kernel.org/r/20231208073036.7884-4-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202311302042.sn8cDPIX-lkp@intel.com/
Cc: Eric DeVolder <eric_devolder@yahoo.com>
Cc: Ignat Korchagin <ignat@cloudflare.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

MIPS: SMP_CPS: Switch to hotplug core state synchronization

Switch to the CPU hotplug core state tracking and synchronization
mechanim. This unfortunately requires to add dead reporting to the non CPS
platforms as CPS is the only user, but it allows an overall consolidation
of this functionality.

No functional change intended.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Helge Deller <deller@gmx.de> # parisc
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck
Link: https://lore.kernel.org/r/20230512205256.803238859@linutronix.de

mips/cpu: Expose play_dead()'s prototype definition

Include <asm/smp.h> to make sure play_dead() matches its prototype going
forward.

Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Link: https://lkml.kernel.org/r/20230216184249.ogaqsaykottpxtcb@treble
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>

mips: clean up kernel-doc in cavium-octeon/*.c

Convert function comments to kernel-doc notation to remove
kernel-doc warnings in arch/mips/cavium-octeon/*.c.
Also clean up the comments in a few places.

arch/mips/cavium-octeon/flash_setup.c:66: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Module/ driver initialization.
--
arch/mips/cavium-octeon/setup.c:308: warning: expecting prototype for Return non zero if we are currently running in the Octeon simulator(). Prototype was for octeon_is_simulation() instead
arch/mips/cavium-octeon/setup.c:314: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Return true if Octeon is in PCI Host mode. This means
arch/mips/cavium-octeon/setup.c:334: warning: expecting prototype for Get the clock rate of Octeon(). Prototype was for octeon_get_clock_rate() instead
arch/mips/cavium-octeon/setup.c:351: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Write to the LCD display connected to the bootbus. This display
arch/mips/cavium-octeon/setup.c:380: warning: expecting prototype for Return the console uart passed by the bootloader(). Prototype was for octeon_get_boot_uart() instead
arch/mips/cavium-octeon/setup.c:386: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Get the coremask Linux was booted on.
arch/mips/cavium-octeon/setup.c:399: warning: expecting prototype for Check the hardware BIST results for a CPU(). Prototype was for octeon_check_cpu_bist() instead
arch/mips/cavium-octeon/setup.c:432: warning: expecting prototype for Reboot Octeon(). Prototype was for octeon_restart() instead
arch/mips/cavium-octeon/setup.c:452: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Permanently stop a core.
arch/mips/cavium-octeon/setup.c:475: warning: expecting prototype for Halt the system(). Prototype was for octeon_halt() instead
arch/mips/cavium-octeon/setup.c:520: warning: expecting prototype for Return a string representing the system type(). Prototype was for octeon_board_type_string() instead
arch/mips/cavium-octeon/setup.c:661: warning: expecting prototype for Early entry point for arch setup(). Prototype was for prom_init() instead
--
arch/mips/cavium-octeon/smp.c:100: warning: Function parameter or member 'cpu' not described in 'octeon_send_ipi_single'
arch/mips/cavium-octeon/smp.c:100: warning: Function parameter or member 'action' not described in 'octeon_send_ipi_single'
arch/mips/cavium-octeon/smp.c:100: warning: expecting prototype for Cause the function described by call_data to be executed on the passed(). Prototype was for octeon_send_ipi_single() instead
arch/mips/cavium-octeon/smp.c:119: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Detect available CPUs, populate cpu_possible_mask
arch/mips/cavium-octeon/smp.c:210: warning: Function parameter or member 'cpu' not described in 'octeon_boot_secondary'
arch/mips/cavium-octeon/smp.c:210: warning: Function parameter or member 'idle' not described in 'octeon_boot_secondary'
arch/mips/cavium-octeon/smp.c:210: warning: expecting prototype for Firmware CPU startup hook(). Prototype was for octeon_boot_secondary() instead
arch/mips/cavium-octeon/smp.c:236: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* After we've done initial boot, this function is called to allow the
arch/mips/cavium-octeon/smp.c:258: warning: Function parameter or member 'max_cpus' not described in 'octeon_prepare_cpus'
arch/mips/cavium-octeon/smp.c:258: warning: expecting prototype for Callout to firmware before smp_init(). Prototype was for octeon_prepare_cpus() instead
arch/mips/cavium-octeon/smp.c:276: warning: expecting prototype for Last chance for the board code to finish SMP initialization before(). Prototype was for octeon_smp_finish() instead

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Aditya Srivastava <yashsri421@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: linux-mips@vger.kernel.org
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: No need to check CPU 0 in {loongson3,bmips,octeon}_cpu_disable()

After commit 9cce844abf07 ("MIPS: CPU#0 is not hotpluggable"),
c->hotpluggable is 0 for CPU 0 and it will not generate a control
file in sysfs for this CPU:

[root@linux loongson]# cat /sys/devices/system/cpu/cpu0/online
cat: /sys/devices/system/cpu/cpu0/online: No such file or directory
[root@linux loongson]# echo 0 > /sys/devices/system/cpu/cpu0/online
bash: /sys/devices/system/cpu/cpu0/online: Permission denied

So no need to check CPU 0 in {loongson3,bmips,octeon}_cpu_disable(),
just remove them.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: OCTEON: smp: make internal symbols static

Make internal symbols static.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21192/
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@linux-mips.org

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

MIPS: SMP: Allow boot_secondary SMP op to return errors

Allow the boot_secondary SMP op to return an error to __cpu_up(), which
will in turn return it to its caller.

This will allow SMP implementations to return errors quickly in cases
they they know have failed, rather than relying upon __cpu_up()
eventually timing out waiting for the cpu_running completion.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17014/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

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>

MIPS: Add missing include files

After the split of linux/sched.h, several platforms in arch/mips stopped building.

Add the respective additional #include statements to fix the problem I first
tried adding these into asm/processor.h, but ran into circular header
dependencies with that which I could not figure out.

The commit I listed as causing the problem is the branch merge, as there is
likely a combination of multiple patches in that branch.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Cc: ralf@linux-mips.org
Fixes: 1827adb11ad2 ("Merge branch 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip")
Link: http://lkml.kernel.org/r/20170308072931.3836696-1-arnd@arndb.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/hotplug.h>

We are going to split <linux/sched/hotplug.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/hotplug.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

MIPS: Audit and remove any unnecessary uses of module.h

Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends. That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig. In the case of
some code where it is modular, we can extend that to also include
files that are building basic support functionality but not related
to loading or registering the final module; such files also have
no need whatsoever for module.h

The advantage in removing such instances is that module.h itself
sources about 15 other headers; adding significantly to what we feed
cpp, and it can obscure what headers we are effectively using.

Since module.h might have been the implicit source for init.h
(for __init) and for export.h (for EXPORT_SYMBOL) we consider each
instance for the presence of either and replace/add as needed.

Also note that MODULE_DEVICE_TABLE is a no-op for non-modular code.

Build coverage of all the mips defconfigs revealed the module.h
header was masking a couple of implicit include instances, so
we add the appropriate headers there.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: David Daney <david.daney@cavium.com>
Cc: John Crispin <john@phrozen.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: "Steven J. Hill" <steven.hill@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15131/
[james.hogan@imgtec.com: Preserve sort order where it already exists]
Signed-off-by: James Hogan <james.hogan@imgtec.com>

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>

MIPS: Octeon: Enable KASLR

This patch enables KASLR for Octeon systems. The SMP startup code is
such that the secondaries monitor the volatile variable
'octeon_processor_relocated_kernel_entry' for any non-zero value.
The 'plat_post_relocation hook' is used to set that value to the
kernel entry point of the relocated kernel. The secondary CPUs will
then jusmp to the new kernel, perform their initialization again
and begin waiting for the boot CPU to start them via the relocated
loop 'octeon_spin_wait_boot'. Inspired by Steven's code from Cavium.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Signed-off-by: Steven J. Hill <steven.hill@cavium.com>
Acked-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14669/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

mips/octeon/smp: Convert to hotplug state machine

Install the callbacks via the state machine.

[ tglx: Renamed the state to MIPS_SOC_PREPARE so it can be reused by other
SOCs ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160906170457.32393-16-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

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>

MIPS: Add missing FROZEN hotplug notifier transitions

The corresponding FROZEN hotplug notifier transitions used on
suspend/resume are ignored. Therefore the switch case action argument
is masked with the frozen hotplug notifier transition mask.

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: rt@linutronix.de
Patchwork: https://patchwork.linux-mips.org/patch/13351/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Octeon: Mark some functions __init in smp.c

octeon_smp_setup and octeon_prepare_cpus are just used during initialization
period, so mark them as __init. And, octeon_prepare_cpus is just used in smp.c,
so make it static as well.

Signed-off-by: Yang Shi <yang.shi@windriver.com>
Cc: david.daney@cavium.com
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12574/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: OCTEON: Add SMP support for OCTEON cn78xx et al.

OCTEON chips with the CIU3 interrupt controller use a different IPI
mechanism that previous models.

Add plat_smp_ops for the cn78xx and probing code to choose between the
two types of ops.

Signed-off-by: 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/12499/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: OCTEON: Extend number of supported CPUs past 32

To support more than 48 CPUs, the bootinfo structure grows a new
coremask structure. Add the definition of the structure and add it to
struct cvmx_bootinfo. In prom_init(), copy the new coremask data into
the sysinfo structure, and use it in smp_setup().

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12319/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Octeon: Use __flush_cache_all instead of flush_cache_all.

flush_cache_all will go away.

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

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>

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>

mips: fix up obsolete cpu function usage.

Thanks to spatch, plus manual removal of "&*". Then a sweep for
for_each_cpu_mask => for_each_cpu.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: linux-mips@linux-mips.org

MIPS: OCTEON: fix kernel crash when offlining a CPU

octeon_cpu_disable() will unconditionally enable interrupts when called.
We can assume that the routine is always called with interrupts disabled,
so just delete the incorrect local_irq_disable/enable().

The patch fixes the following crash when offlining a CPU:

[ 93.818785] ------------[ cut here ]------------
[ 93.823421] WARNING: CPU: 1 PID: 10 at kernel/smp.c:231 flush_smp_call_function_queue+0x1c4/0x1d0()
[ 93.836215] Modules linked in:
[ 93.839287] CPU: 1 PID: 10 Comm: migration/1 Not tainted 3.19.0-rc4-octeon-los_b5f0 #1
[ 93.847212] Stack : 0000000000000001 ffffffff81b2cf90 0000000000000004 ffffffff81630000
0000000000000000 0000000000000000 0000000000000000 000000000000004a
0000000000000006 ffffffff8117e550 0000000000000000 0000000000000000
ffffffff81b30000 ffffffff81b26808 8000000032c77748 ffffffff81627e07
ffffffff81595ec8 ffffffff81b26808 000000000000000a 0000000000000001
0000000000000001 0000000000000003 0000000010008ce1 ffffffff815030c8
8000000032cbbb38 ffffffff8113d42c 0000000010008ce1 ffffffff8117f36c
8000000032c77300 8000000032cbba50 0000000000000001 ffffffff81503984
0000000000000000 0000000000000000 0000000000000000 0000000000000000
0000000000000000 ffffffff81121668 0000000000000000 0000000000000000
...
[ 93.912819] Call Trace:
[ 93.915273] [<ffffffff81121668>] show_stack+0x68/0x80
[ 93.920335] [<ffffffff81503984>] dump_stack+0x6c/0x90
[ 93.925395] [<ffffffff8113d58c>] warn_slowpath_common+0x94/0xd8
[ 93.931324] [<ffffffff811a402c>] flush_smp_call_function_queue+0x1c4/0x1d0
[ 93.938208] [<ffffffff811a4128>] hotplug_cfd+0xf0/0x108
[ 93.943444] [<ffffffff8115bacc>] notifier_call_chain+0x5c/0xb8
[ 93.949286] [<ffffffff8113d704>] cpu_notify+0x24/0x60
[ 93.954348] [<ffffffff81501738>] take_cpu_down+0x38/0x58
[ 93.959670] [<ffffffff811b343c>] multi_cpu_stop+0x154/0x180
[ 93.965250] [<ffffffff811b3768>] cpu_stopper_thread+0xd8/0x160
[ 93.971093] [<ffffffff8115ea4c>] smpboot_thread_fn+0x1ec/0x1f8
[ 93.976936] [<ffffffff8115ab04>] kthread+0xd4/0xf0
[ 93.981735] [<ffffffff8111c4f0>] ret_from_kernel_thread+0x14/0x1c
[ 93.987835]
[ 93.989326] ---[ end trace c9e3815ee655bda9 ]---
[ 93.993951] Kernel bug detected[#1]:
[ 93.997533] CPU: 1 PID: 10 Comm: migration/1 Tainted: G W 3.19.0-rc4-octeon-los_b5f0 #1
[ 94.006591] task: 8000000032c77300 ti: 8000000032cb8000 task.ti: 8000000032cb8000
[ 94.014081] $ 0 : 0000000000000000 0000000010000ce1 0000000000000001 ffffffff81620000
[ 94.022146] $ 4 : 8000000002c72ac0 0000000000000000 00000000000001a7 ffffffff813b06f0
[ 94.030210] $ 8 : ffffffff813b20d8 0000000000000000 0000000000000000 ffffffff81630000
[ 94.038275] $12 : 0000000000000087 0000000000000000 0000000000000086 0000000000000000
[ 94.046339] $16 : ffffffff81623168 0000000000000001 0000000000000000 0000000000000008
[ 94.054405] $20 : 0000000000000001 0000000000000001 0000000000000001 0000000000000003
[ 94.062470] $24 : 0000000000000038 ffffffff813b7f10
[ 94.070536] $28 : 8000000032cb8000 8000000032cbbc20 0000000010008ce1 ffffffff811bcaf4
[ 94.078601] Hi : 0000000000f188e8
[ 94.082179] Lo : d4fdf3b646c09d55
[ 94.085760] epc : ffffffff811bc9d0 irq_work_run_list+0x8/0xf8
[ 94.091686] Tainted: G W
[ 94.095613] ra : ffffffff811bcaf4 irq_work_run+0x34/0x60
[ 94.101192] Status: 10000ce3 KX SX UX KERNEL EXL IE
[ 94.106235] Cause : 40808034
[ 94.109119] PrId : 000d9301 (Cavium Octeon II)
[ 94.113653] Modules linked in:
[ 94.116721] Process migration/1 (pid: 10, threadinfo=8000000032cb8000, task=8000000032c77300, tls=0000000000000000)
[ 94.127168] Stack : 8000000002c74c80 ffffffff811a4128 0000000000000001 ffffffff81635720
fffffffffffffff2 ffffffff8115bacc 80000000320fbce0 80000000320fbca4
80000000320fbc80 0000000000000002 0000000000000004 ffffffff8113d704
80000000320fbce0 ffffffff81501738 0000000000000003 ffffffff811b343c
8000000002c72aa0 8000000002c72aa8 ffffffff8159cae8 ffffffff8159caa0
ffffffff81650000 80000000320fbbf0 80000000320fbc80 ffffffff811b32e8
0000000000000000 ffffffff811b3768 ffffffff81622b80 ffffffff815148a8
8000000032c77300 8000000002c73e80 ffffffff815148a8 8000000032c77300
ffffffff81622b80 ffffffff815148a8 8000000032c77300 ffffffff81503f48
ffffffff8115ea0c ffffffff81620000 0000000000000000 ffffffff81174d64
...
[ 94.192771] Call Trace:
[ 94.195222] [<ffffffff811bc9d0>] irq_work_run_list+0x8/0xf8
[ 94.200802] [<ffffffff811bcaf4>] irq_work_run+0x34/0x60
[ 94.206036] [<ffffffff811a4128>] hotplug_cfd+0xf0/0x108
[ 94.211269] [<ffffffff8115bacc>] notifier_call_chain+0x5c/0xb8
[ 94.217111] [<ffffffff8113d704>] cpu_notify+0x24/0x60
[ 94.222171] [<ffffffff81501738>] take_cpu_down+0x38/0x58
[ 94.227491] [<ffffffff811b343c>] multi_cpu_stop+0x154/0x180
[ 94.233072] [<ffffffff811b3768>] cpu_stopper_thread+0xd8/0x160
[ 94.238914] [<ffffffff8115ea4c>] smpboot_thread_fn+0x1ec/0x1f8
[ 94.244757] [<ffffffff8115ab04>] kthread+0xd4/0xf0
[ 94.249555] [<ffffffff8111c4f0>] ret_from_kernel_thread+0x14/0x1c
[ 94.255654]
[ 94.257146]
Code: a2423c40 40026000 30420001 <00020336> dc820000 10400037 00000000 0000010f 0000010f
[ 94.267183] ---[ end trace c9e3815ee655bdaa ]---
[ 94.271804] Fatal exception: panic in 5 seconds

Reported-by: Hemmo Nieminen <hemmo.nieminen@iki.fi>
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: David Daney <david.daney@cavium.com>
Cc: stable@vger.kernel.org # v3.18+
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8952/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: OCTEON: disable HOTPLUG_CPU if the bootloader version is incorrect

Disable HOTPLUG_CPU functionality if the bootloader version is incorrect.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: linux-mips@linux-mips.org
Cc: David Daney <ddaney.cavm@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/7200/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: OCTEON: support disabling HOTPLUG_CPU run-time

If nosmp kernel option given, we can assume HOTPLUG_CPU is disabled.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7202/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: OCTEON: SMP: delete redundant check

The same check is already done earlier in octeon_smp_hotplug_setup().

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Patchwork: https://patchwork.linux-mips.org/patch/7199/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: SMP: Remove plat_smp_ops cpus_done method.

Nothing was using the method and there isn't any need for this hook. This
leaves smp_cpus_done() empty for the moment.

As suggested by Paul Bolle <pebolle@tiscali.nl>.

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

MIPS: Octeon: Remove checks for CONFIG_CAVIUM_GDB

Three checks for CONFIG_CAVIUM_GDB were added in v2.6.29. But the
Kconfig symbol CAVIUM_GDB was never added to the tree. Remove these
checks.

Also remove the last reference to octeon_get_boot_debug_flag(). There is
no definition of that function anyway.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Tested-by: Andreas Herrmann <andreas.herrmann@caviumnetworks.com>)
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/6976/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

mips: delete non-required instances of include <linux/init.h>

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/

MIPS: Move declaration of Octeon function fixup_irqs() to header.

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

MIPS: Delete __cpuinit/__CPUINIT usage from MIPS code

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>

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>

MIPS: Octeon: delay enable irq to ->smp_finish()

To prepare for smoothing set_cpu_[active|online]() mess up

Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Cc: Sergei Shtylyov <sshtylyov@mvista.com>
Cc: David Daney <david.daney@cavium.com>
Acked-by: David Daney <david.daney@cavium.com>
Patchwork: https://patchwork.linux-mips.org/patch/3845/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Cavium: Remove smp_reserve_lock.

There is nothing that is protected by this lock and it's getting in the
way of RT.

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

documentation: remove references to cpu_*_map.

This has been obsolescent for a while, fix documentation and
misc comments.

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

remove references to cpu_*_map in arch/

This has been obsolescent for a while; time for the final push.

In adjacent context, replaced old cpus_* with cpumask_*.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: David S. Miller <davem@davemloft.net> (arch/sparc)
Acked-by: Chris Metcalf <cmetcalf@tilera.com> (arch/tile)
Cc: user-mode-linux-devel@lists.sourceforge.net
Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: linux-hexagon@vger.kernel.org
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: sparclinux@vger.kernel.org

Disintegrate asm/system.h for MIPS

Disintegrate asm/system.h for MIPS.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
cc: linux-mips@linux-mips.org

MIPS: Fix up inconsistency in panic() string argument.

Panic() invokes printk() to add a \n internally, so panic arguments should
not themselves end in \n. Panic invocations in arch/mips and elsewhere
are inconsistently sometimes terminating in \n, sometimes not.

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

MIPS: Octeon: Mark SMP-IPI interrupt as IRQF_NO_THREAD

This is to exclude it from force threading to allow RT patch set to work.
And while on this line
* Remove IRQF_DISABLED as as this flag is NOOP
* Add IRQF_PERCPU as this is a per cpu interrupt.

Signed-off-by: Venkat Subbiah <venkat.subbiah@cavium.com>
Acked-by: David Daney <david.daney@cavium.com>
To: linux-mips@linux-mips.org
To: linux-rt-users@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/2817/
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Octeon: Don't request interrupts for unused IPI mailbox bits.

We only use the three low-order mailbox bits. Leave the upper bits alone
for possible use by drivers and other software.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2090/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

sched: Provide scheduler_ipi() callback in response to smp_send_reschedule()

For future rework of try_to_wake_up() we'd like to push part of that
function onto the CPU the task is actually going to run on.

In order to do so we need a generic callback from the existing scheduler IPI.

This patch introduces such a generic callback: scheduler_ipi() and
implements it as a NOP.

BenH notes: PowerPC might use this IPI on offline CPUs under rare conditions!

Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reviewed-by: Frank Rowand <frank.rowand@am.sony.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110405152728.744338123@chello.nl

MIPS: Octeon: Rewrite interrupt handling code.

This includes conversion to new style irq_chip functions, and
correctly enabling/disabling per-CPU interrupts.

The hardware interrupt bit to irq number mapping is now done with a
flexible map, instead of by bit twiddling the irq number.

[ tglx: Adjusted to new irq_cpu_on/offline callbacks and
__irq_set_affinity_lock ]

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Cc: ralf@linux-mips.org
LKML-Reference: <1301081931-11240-5-git-send-email-ddaney@caviumnetworks.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

MIPS: Octeon: HOTPLUG_CPU fixes.

* Rename camel-case InitTLBStart_addr to octeon_bootloader_entry_addr.

* Convert calls to cvmx_read64_uint32(), to simple pointer
dereferences.

* Set proper ebase.

* Don't confuse coreid and cpu numbers.

* Try to maintain consistent bootloader coremask.

* Update the signature and boot_init_vector of supported bootloaders.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1491/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Octeon: Simplify hotcpu_notifier registration.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1490/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Octeon: Clean up SMP CPU numbering.

Also number offline CPUs that could potentially be brought on-line
later.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1489/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Cavium: Remove unused watchdog code.

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

MIPS: Remove trailing space in messages

Signed-off-by: Frans Pop <elendil@planet.nl>
To: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/946/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Octeon: Fix compile error in arch/mips/cavium-octeon/smp.c

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Octeon: Run IPI code with interrupts disabled.

In mm/slab.c the function do_ccupdate_local requires that interrupts be
disabled. If they are not, we panic with CONFIG_DEBUG_SLAB.

So we disable interrupts while processing IPIs. Also these are not shared
irqs, so get rid of the IRQF_SHARED flag.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Cavium: Add CPU hotplugging code.

Thanks to Cavium Inc. for the code contribution and help.

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

MIPS: Add Cavium OCTEON processor support files to arch/mips/cavium-octeon.

These are the rest of the new files needed to add OCTEON processor
support to the Linux kernel. Other than Makefile and Kconfig which
should be obvious, we have:

csrc-octeon.c -- Clock source driver for OCTEON.
dma-octeon.c -- Helper functions for mapping DMA memory.
flash_setup.c -- Register on-board flash with the MTD subsystem.
octeon-irq.c -- OCTEON interrupt controller managment.
octeon-memcpy.S -- Optimized memcpy() implementation.
serial.c -- Register 8250 platform driver and early console.
setup.c -- Early architecture initialization.
smp.c -- OCTEON SMP support.
octeon_switch.S -- Scheduler context switch for OCTEON.
c-octeon.c -- OCTEON cache controller support.
cex-oct.S -- OCTEON cache exception handler.

asm/mach-cavium-octeon/*.h -- Architecture include files.

Signed-off-by: Tomaso Paoletti <tpaoletti@caviumnetworks.com>
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

create mode 100644 arch/mips/cavium-octeon/Kconfig
create mode 100644 arch/mips/cavium-octeon/Makefile
create mode 100644 arch/mips/cavium-octeon/csrc-octeon.c
create mode 100644 arch/mips/cavium-octeon/dma-octeon.c
create mode 100644 arch/mips/cavium-octeon/flash_setup.c
create mode 100644 arch/mips/cavium-octeon/octeon-irq.c
create mode 100644 arch/mips/cavium-octeon/octeon-memcpy.S
create mode 100644 arch/mips/cavium-octeon/serial.c
create mode 100644 arch/mips/cavium-octeon/setup.c
create mode 100644 arch/mips/cavium-octeon/smp.c
create mode 100644 arch/mips/include/asm/mach-cavium-octeon/cpu-feature-overrides.h
create mode 100644 arch/mips/include/asm/mach-cavium-octeon/dma-coherence.h
create mode 100644 arch/mips/include/asm/mach-cavium-octeon/irq.h
create mode 100644 arch/mips/include/asm/mach-cavium-octeon/kernel-entry-init.h
create mode 100644 arch/mips/include/asm/mach-cavium-octeon/war.h
create mode 100644 arch/mips/include/asm/octeon/octeon.h
create mode 100644 arch/mips/kernel/octeon_switch.S
create mode 100644 arch/mips/mm/c-octeon.c
create mode 100644 arch/mips/mm/cex-oct.S