linux-toradex.git/drivers/cpuidle/cpuidle-pseries.c, branch v3.17.2

cpuidle/pseries: Fix fallout caused due to cleanup in pseries cpuidle backend driver

2014-02-12T07:05:03+00:00

Commit d8c6ad3184ca651 ("sched/idle, PPC: Remove redundant
cpuidle_idle_call()") reintroduced ppc64_runlatch_off/on() in the
pseries cpuidle backend driver. Hence the cleanup caused by the
commit "c0c4301c54adde05:pseries/cpuidle: Remove redundant call
to ppc64_runlatch_off() in cpu idle routines"  in conjuction
with the commit d8c6ad3184ca651 causes a build failure.

Signed-off-by: Preeti U Murthy 
Cc: Peter Zijlstra 
Cc: Nicolas Pitre 
Cc: Stephen Rothwell 
Link: http://lkml.kernel.org/r/52FAFD2D.2090306@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar

sched/idle, PPC: Remove redundant cpuidle_idle_call()

2014-02-11T08:58:24+00:00

The core idle loop now takes care of it.  However a few things need
checking:

- Invocation of cpuidle_idle_call() in pseries_lpar_idle() happened
  through arch_cpu_idle() and was therefore always preceded by a call
  to ppc64_runlatch_off().  To preserve this property now that
  cpuidle_idle_call() is invoked directly from core code, a call to
  ppc64_runlatch_off() has been added to idle_loop_prolog() in
  platforms/pseries/processor_idle.c.

- Similarly, cpuidle_idle_call() was followed by ppc64_runlatch_off()
  so a call to the later has been added to idle_loop_epilog().

- And since arch_cpu_idle() always made sure to re-enable IRQs if they
  were not enabled, this is now
  done in idle_loop_epilog() as well.

The above was made in order to keep the execution flow close to the
original.  I don't know if that was strictly necessary. Someone well
aquainted with the platform details might find some room for possible
optimizations.

Signed-off-by: Nicolas Pitre 
Reviewed-by: Preeti U Murthy 
Cc: "Rafael J. Wysocki" 
Cc: Daniel Lezcano 
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-sh@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: Russell King 
Cc: linaro-kernel@lists.linaro.org
Cc: Benjamin Herrenschmidt 
Cc: Paul Mundt 
Signed-off-by: Peter Zijlstra 
Link: http://lkml.kernel.org/n/tip-47o4m03citrfg9y1vxic5asb@git.kernel.org
Signed-off-by: Ingo Molnar

powerpc/pseries/cpuidle: smt-snooze-delay cleanup.

2014-01-29T06:02:24+00:00

smt-snooze-delay was designed to disable NAP state or delay the entry
to the NAP state prior to adoption of cpuidle framework. This
is per-cpu variable. With the coming of CPUIDLE framework,
states can be disabled on per-cpu basis using the cpuidle/enable
sysfs entry.

Also, with the coming of cpuidle driver each state's target residency
is per-driver unlike earlier which was per-device. Therefore,
the per-cpu sysfs smt-snooze-delay which decides the target residency
of the idle state on a particular cpu causes more confusion to the user
as we cannot have different smt-snooze-delay (target residency)
values for each cpu.

In the current code, smt-snooze-delay functionality is completely broken.
It makes sense to remove smt-snooze-delay from idle driver with the
coming of cpuidle framework.
However, sysfs files are retained as ppc64_util currently
utilises it. Once we fix ppc64_util, propose to clean
up the kernel code.

Signed-off-by: Deepthi Dharwar 
Signed-off-by: Benjamin Herrenschmidt

powerpc/pseries/cpuidle: Remove MAX_IDLE_STATE macro.

2014-01-29T06:02:23+00:00

This patch removes the usage of MAX_IDLE_STATE macro
and dead code around it. The number of states
are determined at run time based on the cpuidle
state table selected on a given platform

Signed-off-by: Deepthi Dharwar 
Signed-off-by: Benjamin Herrenschmidt

powerpc/pseries/cpuidle: Make cpuidle-pseries backend driver a non-module.

2014-01-29T06:02:23+00:00

Currently cpuidle-pseries backend driver cannot be
built as a module due to dependencies wrt cpuidle framework.
This patch removes all the module related code in the driver.

Signed-off-by: Deepthi Dharwar 
Signed-off-by: Benjamin Herrenschmidt

powerpc/pseries/cpuidle: Use cpuidle_register() for initialisation.

2014-01-29T06:02:22+00:00

This patch replaces the cpuidle driver and devices initialisation
calls with a single generic cpuidle_register() call
and also includes minor refactoring of the code around it.

Remove the cpu online check in snooze loop, as this code can
only locally run on a cpu only if it is online. Therefore,
this check is not required.

Signed-off-by: Deepthi Dharwar 
Signed-off-by: Benjamin Herrenschmidt

powerpc/pseries/cpuidle: Move processor_idle.c to drivers/cpuidle.

2014-01-29T06:02:22+00:00

Move the file from arch specific pseries/processor_idle.c
to drivers/cpuidle/cpuidle-pseries.c
Make the relevant Makefile and Kconfig changes.
Also, introduce Kconfig.powerpc in drivers/cpuidle
for all powerpc cpuidle drivers.

Signed-off-by: Deepthi Dharwar 
Signed-off-by: Benjamin Herrenschmidt