Commit Graph

10 Commits

Author SHA1 Message Date
Masahiro Yamada
75305275a7 ARM: use const and __initconst for smp_operations
These smp_operations structures are not over-written, so add "const"
qualifier and replace __initdata with __initconst.

Also, add "static" where it is possible.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Moritz Fischer <moritz.fischer@ettus.com>
Acked-by: Stephen Boyd <sboyd@codeaurora.org> # qcom part
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Patrice Chotard <patrice.chotard@st.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Wei Xu <xuwei5@hisilicon.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Acked-by: Shawn Guo <shawnguo@kernel.org>
Acked-by: Matthias Brugger <matthias.bgg@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Liviu Dudau <Liviu.Dudau@arm.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2015-12-01 22:17:45 +01:00
Stephen Boyd
787047eea2 ARM: 8392/3: smp: Only expose /sys/.../cpuX/online if hotpluggable
Writes to /sys/.../cpuX/online fail if we determine the platform
doesn't support hotplug for that CPU. Furthermore, if the cpu_die
op isn't specified the system hangs when we try to offline a CPU
and it comes right back online unexpectedly. Let's figure this
stuff out before we make the sysfs nodes so that the online file
doesn't even exist if it isn't (at least sometimes) possible to
hotplug the CPU.

Add a new 'cpu_can_disable' op and repoint all 'cpu_disable'
implementations at it because all implementers use the op to
indicate if a CPU can be hotplugged or not in a static fashion.
With PSCI we may need to add a 'cpu_disable' op so that the
secure OS can be migrated off the CPU we're trying to hotplug.
In this case, the 'cpu_can_disable' op will indicate that all
CPUs are hotpluggable by returning true, but the 'cpu_disable' op
will make a PSCI migration call and occasionally fail, denying
the hotplug of a CPU. This shouldn't be any worse than x86 where
we may indicate that all CPUs are hotpluggable but occasionally
we can't offline a CPU due to check_irq_vectors_for_cpu_disable()
failing to find a CPU to move vectors to.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Dave Martin <Dave.Martin@arm.com>
Acked-by: Simon Horman <horms@verge.net.au> [shmobile portion]
Tested-by: Simon Horman <horms@verge.net.au>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: <linux-sh@vger.kernel.org>
Tested-by: Tyler Baker <tyler.baker@linaro.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-07-31 18:58:30 +01:00
Dave Martin
166aaf3966 ARM: 8029/1: mcpm: Rename the power_down_finish() functions to be less confusing
The name "power_down_finish" seems to be causing some confusion,
because it suggests that this function is responsible for taking
some action to cause the specified CPU to complete its power down.

This patch renames the affected functions to "wait_for_powerdown"
and similar, since this function's intended purpose is just to wait
for the hardware to finish a powerdown initiated by a previous
cpu_power_down.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-05-25 23:48:12 +01:00
Dave Martin
0de0d64675 ARM: 7848/1: mcpm: Implement cpu_kill() to synchronise on powerdown
CPU hotplug and kexec rely on smp_ops.cpu_kill(), which is supposed
to wait for the CPU to park or power down, and perform the last
rites (such as disabling clocks etc., where the platform doesn't do
this automatically).

kexec in particular is unsafe without performing this
synchronisation to park secondaries.  Without it, the secondaries
might not be parked when kexec trashes the kernel.

There is no generic way to do this synchronisation, so a new mcpm
platform_ops method power_down_finish() is added by this patch.

The new method is mandatory.  A platform which provides no way to
detect when CPUs are parked is likely broken.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-10-29 11:07:15 +00:00
Dave Martin
1e5660999a ARM: 7847/1: mcpm: Factor out logical-to-physical CPU translation
This patch factors the logical-to-physical CPU translation out of
mcpm_boot_secondary(), so that it can be reused elsewhere.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-10-29 11:06:34 +00:00
Paul Gortmaker
8bd26e3a7e arm: delete __cpuinit/__CPUINIT usage from all ARM users
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.

This removes all the ARM uses of the __cpuinit macros from C code,
and all __CPUINIT from assembly code.  It also had two ".previous"
section statements that were paired off against __CPUINIT
(aka .section ".cpuinit.text") that also get removed here.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Russell King <linux@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-07-14 19:36:52 -04:00
Nicolas Pitre
6c93dd438a ARM: 7741/1: mcpm_platsmp.c: remove empty smp_init_cpus method
The smp_init_cpus method in the smp_operations structure is optional
and can be omitted entirely.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-06-05 23:58:10 +01:00
Nicolas Pitre
9e01573b5c ARM: 7715/1: MCPM: adapt to GIC changes after upstream merge
Since commit c0114709ed ("irqchip: gic: Perform the gic_secondary_init()
call via CPU notifier") it is no longer required nor possible to call
gic_secondary_init() from platform code.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-05-10 14:44:19 +01:00
Nicolas Pitre
a7eb7c6f9a ARM: mcpm: provide an interface to set the SMP ops at run time
This is cleaner than exporting the mcpm_smp_ops structure.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Jon Medhurst <tixy@linaro.org>
2013-04-24 10:37:03 -04:00
Nicolas Pitre
9ff221bad8 ARM: mcpm: generic SMP secondary bringup and hotplug support
Now that the cluster power API is in place, we can use it for SMP secondary
bringup and CPU hotplug in a generic fashion.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
2013-04-24 10:37:02 -04:00