Commit Graph

30 Commits

Author SHA1 Message Date
Rafael J. Wysocki
060d0fbb43 Merge branches 'pm-cpuidle', 'pm-core', 'pm-domains', 'pm-avs' and 'pm-devfreq'
* pm-cpuidle:
  cpuidle: powernv: Avoid a branch in the core snooze_loop() loop
  cpuidle: powernv: Don't continually set thread priority in snooze_loop()
  cpuidle: powernv: Don't bounce between low and very low thread priority
  cpuidle: cpuidle-cps: remove unused variable
  powernv-cpuidle: Validate DT property array size

* pm-core:
  PM / runtime: Document autosuspend-helper side effects
  PM / runtime: Fix autosuspend documentation

* pm-domains:
  PM / Domains: Ignore domain-idle-states that are not compatible
  PM / Domains: Don't warn about IRQ safe device for an always on PM domain
  PM / Domains: Respect errors from genpd's ->power_off() callback
  PM / Domains: Enable users of genpd to specify always on PM domains
  PM / Domains: Clean up code validating genpd's status
  PM / Domain: remove conditional from error case

* pm-avs:
  PM / AVS: rockchip-io: add io selectors and supplies for rk3328

* pm-devfreq:
  PM / devfreq: Move struct devfreq_governor to devfreq directory
2017-04-28 23:15:34 +02:00
Anton Blanchard
0baa91cb73 cpuidle: powernv: Avoid a branch in the core snooze_loop() loop
When in the snooze_loop() we want to take up the least amount of
resources. On my version of gcc (6.3), we end up with an extra
branch because it predicts snooze_timeout_en to be false, whereas it
is almost always true.

Use likely() to avoid the branch and be a little nicer to the
other non idle threads on the core.

Signed-off-by: Anton Blanchard <anton@samba.org>
Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-04-19 23:17:19 +02:00
Anton Blanchard
26eb48a9fa cpuidle: powernv: Don't continually set thread priority in snooze_loop()
The powerpc64 kernel exception handlers have preserved thread priorities
for a long time now, so there is no need to continually set it.

Just set it once on entry and once exit.

Signed-off-by: Anton Blanchard <anton@samba.org>
Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-04-19 23:17:18 +02:00
Anton Blanchard
79b578111f cpuidle: powernv: Don't bounce between low and very low thread priority
The core of snooze_loop() continually bounces between low and very
low thread priority. Changing thread priorities is an expensive
operation that can negatively impact other threads on a core.

All CPUs that can run PowerNV support very low priority, so we can
avoid the change completely.

Signed-off-by: Anton Blanchard <anton@samba.org>
Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-04-19 23:17:18 +02:00
Vaidyanathan Srinivasan
293d264f13 cpuidle: powernv: Pass correct drv->cpumask for registration
drv->cpumask defaults to cpu_possible_mask in __cpuidle_driver_init().
On PowerNV platform cpu_present could be less than cpu_possible in cases
where firmware detects the cpu, but it is not available to the OS.  When
CONFIG_HOTPLUG_CPU=n, such cpus are not hotplugable at runtime and hence
we skip creating cpu_device.

This breaks cpuidle on powernv where register_cpu() is not called for
cpus in cpu_possible_mask that cannot be hot-added at runtime.

Trying cpuidle_register_device() on cpu without cpu_device will cause
crash like this:

cpu 0xf: Vector: 380 (Data SLB Access) at [c000000ff1503490]
    pc: c00000000022c8bc: string+0x34/0x60
    lr: c00000000022ed78: vsnprintf+0x284/0x42c
    sp: c000000ff1503710
   msr: 9000000000009033
   dar: 6000000060000000
  current = 0xc000000ff1480000
  paca    = 0xc00000000fe82d00   softe: 0        irq_happened: 0x01
    pid   = 1, comm = swapper/8
Linux version 4.11.0-rc2 (sv@sagarika) (gcc version 4.9.4
(Buildroot 2017.02-00004-gc28573e) ) #15 SMP Fri Mar 17 19:32:02 IST 2017
enter ? for help
[link register   ] c00000000022ed78 vsnprintf+0x284/0x42c
[c000000ff1503710] c00000000022ebb8 vsnprintf+0xc4/0x42c (unreliable)
[c000000ff1503800] c00000000022ef40 vscnprintf+0x20/0x44
[c000000ff1503830] c0000000000ab61c vprintk_emit+0x94/0x2cc
[c000000ff15038a0] c0000000000acc9c vprintk_func+0x60/0x74
[c000000ff15038c0] c000000000619694 printk+0x38/0x4c
[c000000ff15038e0] c000000000224950 kobject_get+0x40/0x60
[c000000ff1503950] c00000000022507c kobject_add_internal+0x60/0x2c4
[c000000ff15039e0] c000000000225350 kobject_init_and_add+0x70/0x78
[c000000ff1503a60] c00000000053c288 cpuidle_add_sysfs+0x9c/0xe0
[c000000ff1503ae0] c00000000053aeac cpuidle_register_device+0xd4/0x12c
[c000000ff1503b30] c00000000053b108 cpuidle_register+0x98/0xcc
[c000000ff1503bc0] c00000000085eaf0 powernv_processor_idle_init+0x140/0x1e0
[c000000ff1503c60] c00000000000cd60 do_one_initcall+0xc0/0x15c
[c000000ff1503d20] c000000000833e84 kernel_init_freeable+0x1a0/0x25c
[c000000ff1503dc0] c00000000000d478 kernel_init+0x24/0x12c
[c000000ff1503e30] c00000000000b564 ret_from_kernel_thread+0x5c/0x78

This patch fixes the bug by passing correct cpumask from
powernv-cpuidle driver.

Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
[ rjw: Comment massage ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-03-29 22:55:36 +02:00
Gautham R. Shenoy
ecad4502d0 powernv-cpuidle: Validate DT property array size
The various properties associated with powernv idle states such as
names, flags, residency-ns, latencies-ns, psscr, psscr-mask are
exposed in the device-tree as property arrays such the pointwise
entries in each of these arrays correspond to the properties of the
same idle state.

This patch validates that the lengths of the property arrays are the
same. If there is a mismatch, the patch will ensure that we bail out
and not expose the platform idle states via cpuidle.

Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Reviewed-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-03-29 00:14:00 +02:00
Gautham R. Shenoy
09206b600c powernv: Pass PSSCR value and mask to power9_idle_stop
The power9_idle_stop method currently takes only the requested stop
level as a parameter and picks up the rest of the PSSCR bits from a
hand-coded macro. This is not a very flexible design, especially when
the firmware has the capability to communicate the psscr value and the
mask associated with a particular stop state via device tree.

This patch modifies the power9_idle_stop API to take as parameters the
PSSCR value and the PSSCR mask corresponding to the stop state that
needs to be set. These PSSCR value and mask are respectively obtained
by parsing the "ibm,cpu-idle-state-psscr" and
"ibm,cpu-idle-state-psscr-mask" fields from the device tree.

In addition to this, the patch adds support for handling stop states
for which ESL and EC bits in the PSSCR are zero. As per the
architecture, a wakeup from these stop states resumes execution from
the subsequent instruction as opposed to waking up at the System
Vector.

The older firmware sets only the Requested Level (RL) field in the
psscr and psscr-mask exposed in the device tree. For older firmware
where psscr-mask=0xf, this patch will set the default sane values that
the set for for remaining PSSCR fields (i.e PSLL, MTL, ESL, EC, and
TR). For the new firmware, the patch will validate that the invariants
required by the ISA for the psscr values are maintained by the
firmware.

This skiboot patch that exports fully populated PSSCR values and the
mask for all the stop states can be found here:
https://lists.ozlabs.org/pipermail/skiboot/2016-September/004869.html

[Optimize the number of instructions before entering STOP with
ESL=EC=0, validate the PSSCR values provided by the firimware
maintains the invariants required as per the ISA suggested by Balbir
Singh]

Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 08:32:13 +11:00
Gautham R. Shenoy
9e9fc6f00a cpuidle:powernv: Add helper function to populate powernv idle states.
In the current code for powernv_add_idle_states, there is a lot of code
duplication while initializing an idle state in powernv_states table.

Add an inline helper function to populate the powernv_states[] table
for a given idle state. Invoke this for populating the "Nap",
"Fastsleep" and the stop states in powernv_add_idle_states.

Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 08:32:13 +11:00
Andrew Donnellan
ed61390bff cpuidle/powernv: staticise powernv_idle_driver
powernv_idle_driver isn't exported, it can be made static. Found by sparse.

Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-24 22:18:43 +01:00
Sebastian Andrzej Siewior
10fcca9d87 cpuidle/powernv: Convert to hotplug state machine
Install the callbacks via the state machine.

v1…v2: - Use only CPUHP_CPUIDLE_DEAD (requested by Daniel Lezcano)

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-pm@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160824091259.ozyslcopxvbfdqzy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-06 18:30:24 +02:00
Shreyas B. Prabhu
3005c597ba cpuidle/powernv: Add support for POWER ISA v3 idle states
POWER ISA v3 defines a new idle processor core mechanism. In summary,
 a) new instruction named stop is added.
 b) new per thread SPR named PSSCR is added which controls the behavior
	of stop instruction.

Supported idle states and value to be written to PSSCR register to enter
any idle state is exposed via ibm,cpu-idle-state-names and
ibm,cpu-idle-state-psscr respectively. To enter an idle state,
platform provided power_stop() needs to be invoked with the appropriate
PSSCR value.

This patch adds support for this new mechanism in cpuidle powernv driver.

Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>
Cc: linux-pm@vger.kernel.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: linuxppc-dev@lists.ozlabs.org
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-07-15 20:18:42 +10:00
Shreyas B. Prabhu
957efcedee cpuidle/powernv: cleanup cpuidle-powernv.c
- Use stack instead of kzalloc'ed memory for variables while probing
   device tree for idle states.
 - Set cap for number of idle states that can be added to
   cpuidle_state_table
 - Minor change in way we check of_property_read_u32_array for error
   for sake of consistency
 - Drop unnecessary "&" while assigning function pointer

Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-pm@vger.kernel.org
Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-07-15 20:18:42 +10:00
Shreyas B. Prabhu
169f3fae0c cpuidle/powernv: Use CPUIDLE_STATE_MAX instead of MAX_POWERNV_IDLE_STATES
Use cpuidle's CPUIDLE_STATE_MAX macro instead of powernv specific
MAX_POWERNV_IDLE_STATES.

Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-pm@vger.kernel.org
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-07-15 20:18:41 +10:00
Stewart Smith
e4d54f71d2 powerpc/powernv: remove FW_FEATURE_OPALv3 and just use FW_FEATURE_OPAL
Long ago, only in the lab, there was OPALv1 and OPALv2. Now there is
just OPALv3, with nobody ever expecting anything on pre-OPALv3 to
be cared about or supported by mainline kernels.

So, let's remove FW_FEATURE_OPALv3 and instead use FW_FEATURE_OPAL
exclusively.

Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-17 22:40:54 +11:00
preeti
cc5a2f7b8f tick/idle/powerpc: Do not register idle states with CPUIDLE_FLAG_TIMER_STOP set in periodic mode
On some archs, the local clockevent device stops in deep cpuidle states.
The broadcast framework is used to wakeup cpus in these idle states, in
which either an external clockevent device is used to send wakeup ipis
or the hrtimer broadcast framework kicks in in the absence of such a
device. One cpu is nominated as the broadcast cpu and this cpu sends
wakeup ipis to sleeping cpus at the appropriate time. This is the
implementation in the oneshot mode of broadcast.

In periodic mode of broadcast however, the presence of such cpuidle
states results in the cpuidle driver calling tick_broadcast_enable()
which shuts down the local clockevent devices of all the cpus and
appoints the tick broadcast device as the clockevent device for each of
them. This works on those archs where the tick broadcast device is a
real clockevent device.  But on archs which depend on the hrtimer mode
of broadcast, the tick broadcast device hapens to be a pseudo device.
The consequence is that the local clockevent devices of all cpus are
shutdown and the kernel hangs at boot time in periodic mode.

Let us thus not register the cpuidle states which have
CPUIDLE_FLAG_TIMER_STOP flag set, on archs which depend on the hrtimer
mode of broadcast in periodic mode. This patch takes care of doing this
on powerpc. The cpus would not have entered into such deep cpuidle
states in periodic mode on powerpc anyway. So there is no loss here.

Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: 3.19+ <stable@vger.kernel.org> # 3.19+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-26 03:28:49 +02:00
Shilpasri G Bhat
78eaa10f02 cpuidle: powernv/pseries: Auto-promotion of snooze to deeper idle state
The idle cpus which stay in snooze for a long period can degrade the
perfomance of the sibling cpus. If the cpu stays in snooze for more
than target residency of the next available idle state, then exit from
snooze. This gives a chance to the cpuidle governor to re-evaluate the
last idle state of the cpu to promote it to deeper idle states.

Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-22 15:15:15 +02:00
Preeti U Murthy
70734a786a cpuidle: powernv: Avoid endianness conversions while parsing DT
We currently read the information about idle states from the DT
so as to populate the cpuidle table. Use those APIs to read from
the DT that can avoid endianness conversions of the property values
in the cpuidle driver.

Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-19 23:44:38 +01:00
Preeti U Murthy
92c83ff5b4 cpuidle: powernv: Read target_residency value of idle states from DT if available
The device tree now exposes the residency values for different idle states. Read
these values instead of calculating residency from the latency values. The values
exposed in the DT are validated for optimal power efficiency. However to maintain
compatibility with the older firmware code which does not expose residency
values, use default values as a fallback mechanism. While at it, use better
APIs to parse the powermgmt device tree node.

Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Acked-by: Stewart Smith <stewart@linux.vnet.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-18 06:34:17 +01:00
Linus Torvalds
34b85e3574 powerpc updates for 3.19 batch 2
The highlight is the series that reworks the idle management on powernv, which
 allows us to use deeper idle states on those machines.
 
 There's the fix from Anton for the "BUG at kernel/smpboot.c:134!" problem.
 
 An i2c driver for powernv. This is acked by Wolfram Sang, and he asked that we
 take it through the powerpc tree.
 
 A fix for audit from rgb at Red Hat, acked by Paul Moore who is one of the audit
 maintainers.
 
 A patch from Ben to export the symbol map of our OPAL firmware as a sysfs file,
 so that tools can use it.
 
 Also some CXL fixes, a couple of powerpc perf fixes, a fix for smt-enabled, and
 the patch to add __force to get_user() so we can use bitwise types.
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Merge tag 'powerpc-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux

Pull second batch of powerpc updates from Michael Ellerman:
 "The highlight is the series that reworks the idle management on
  powernv, which allows us to use deeper idle states on those machines.

  There's the fix from Anton for the "BUG at kernel/smpboot.c:134!"
  problem.

  An i2c driver for powernv.  This is acked by Wolfram Sang, and he
  asked that we take it through the powerpc tree.

  A fix for audit from rgb at Red Hat, acked by Paul Moore who is one of
  the audit maintainers.

  A patch from Ben to export the symbol map of our OPAL firmware as a
  sysfs file, so that tools can use it.

  Also some CXL fixes, a couple of powerpc perf fixes, a fix for
  smt-enabled, and the patch to add __force to get_user() so we can use
  bitwise types"

* tag 'powerpc-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux:
  powerpc/powernv: Ignore smt-enabled on Power8 and later
  powerpc/uaccess: Allow get_user() with bitwise types
  powerpc/powernv: Expose OPAL firmware symbol map
  powernv/powerpc: Add winkle support for offline cpus
  powernv/cpuidle: Redesign idle states management
  powerpc/powernv: Enable Offline CPUs to enter deep idle states
  powerpc/powernv: Switch off MMU before entering nap/sleep/rvwinkle mode
  i2c: Driver to expose PowerNV platform i2c busses
  powerpc: add little endian flag to syscall_get_arch()
  power/perf/hv-24x7: Use kmem_cache_free() instead of kfree
  powerpc/perf/hv-24x7: Use per-cpu page buffer
  cxl: Unmap MMIO regions when detaching a context
  cxl: Add timeout to process element commands
  cxl: Change contexts_lock to a mutex to fix sleep while atomic bug
  powerpc: Secondary CPUs must set cpu_callin_map after setting active and online
2014-12-19 12:57:45 -08:00
Shreyas B. Prabhu
7cba160ad7 powernv/cpuidle: Redesign idle states management
Deep idle states like sleep and winkle are per core idle states. A core
enters these states only when all the threads enter either the
particular idle state or a deeper one. There are tasks like fastsleep
hardware bug workaround and hypervisor core state save which have to be
done only by the last thread of the core entering deep idle state and
similarly tasks like timebase resync, hypervisor core register restore
that have to be done only by the first thread waking up from these
state.

The current idle state management does not have a way to distinguish the
first/last thread of the core waking/entering idle states. Tasks like
timebase resync are done for all the threads. This is not only is
suboptimal, but can cause functionality issues when subcores and kvm is
involved.

This patch adds the necessary infrastructure to track idle states of
threads in a per-core structure. It uses this info to perform tasks like
fastsleep workaround and timebase resync only once per core.

Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Originally-by: Preeti U. Murthy <preeti@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: linux-pm@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-12-15 10:46:40 +11:00
Shreyas B. Prabhu
8eb8ac89a3 powerpc/powernv: Enable Offline CPUs to enter deep idle states
The secondary threads should enter deep idle states so as to gain maximum
powersavings when the entire core is offline. To do so the offline path
must be made aware of the available deepest idle state. Hence probe the
device tree for the possible idle states in powernv core code and
expose the deepest idle state through flags.

Since the  device tree is probed by the cpuidle driver as well, move
the parameters required to discover the idle states into an appropriate
common place to both the driver and the powernv core code.

Another point is that fastsleep idle state may require workarounds in
the kernel to function properly. This workaround is introduced in the
subsequent patches. However neither the cpuidle driver or the hotplug
path need be bothered about this workaround.

They will be taken care of by the core powernv code.

Originally-by: Srivatsa S. Bhat <srivatsa@mit.edu>
Signed-off-by: Preeti U. Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Reviewed-by: Paul Mackerras <paulus@samba.org>

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: linux-pm@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-12-15 10:46:40 +11:00
Daniel Lezcano
b82b6cca48 cpuidle: Invert CPUIDLE_FLAG_TIME_VALID logic
The only place where the time is invalid is when the ACPI_CSTATE_FFH entry
method is not set. Otherwise for all the drivers, the time can be correctly
measured.

Instead of duplicating the CPUIDLE_FLAG_TIME_VALID flag in all the drivers
for all the states, just invert the logic by replacing it by the flag
CPUIDLE_FLAG_TIME_INVALID, hence we can set this flag only for the acpi idle
driver, remove the former flag from all the drivers and invert the logic with
this flag in the different governor.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-12 21:17:27 +01:00
Preeti U. Murthy
74aa51b5cc cpuidle: powernv: Populate cpuidle state details by querying the device-tree
We hard code the metrics relevant for cpuidle states in the kernel today.
Instead pick them up from the device tree so that they remain relevant
and updated for the system that the kernel is running on.

Signed-off-by: Preeti U. Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-10-21 00:58:58 +02:00
Vaidyanathan Srinivasan
95707d8528 powerpc/cpuidle: Fix parsing of idle state flags from device-tree
Flags from device-tree need to be parsed with accessors for
interpreting correct value in little-endian.

Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Reviewed-by: Preeti U. Murthy <preeti@linux.vnet.ibm.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05 15:40:45 +10:00
Michael Neuling
9b6a68d943 powerpc/cpuidle: Only clear LPCR decrementer wakeup bit on fast sleep entry
Currently when entering fastsleep we clear all LPCR PECE bits.

This patch changes it to only clear the decrementer bit (ie. PECE1), which is
the only bit we really need to clear here.  This is needed if we want to set
other wakeup causes like the PECEDH bit so we can use hypervisor doorbells on
powernv.  Also we no longer clear the MER bit as it should never be set in the
host anyway.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-06-11 17:05:12 +10:00
Linus Torvalds
e6d9bfc638 Merge branch 'powernv-cpuidle' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull powerpc non-virtualized cpuidle from Ben Herrenschmidt:
 "This is the branch I mentioned in my other pull request which contains
  our improved cpuidle support for the "powernv" platform
  (non-virtualized).

  It adds support for the "fast sleep" feature of the processor which
  provides higher power savings than our usual "nap" mode but at the
  cost of losing the timers while asleep, and thus exploits the new
  timer broadcast framework to work around that limitation.

  It's based on a tip timer tree that you seem to have already merged"

* 'powernv-cpuidle' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  cpuidle/powernv: Parse device tree to setup idle states
  cpuidle/powernv: Add "Fast-Sleep" CPU idle state
  powerpc/powernv: Add OPAL call to resync timebase on wakeup
  powerpc/powernv: Add context management for Fast Sleep
  powerpc: Split timer_interrupt() into timer handling and interrupt handling routines
  powerpc: Implement tick broadcast IPI as a fixed IPI message
  powerpc: Free up the slot of PPC_MSG_CALL_FUNC_SINGLE IPI message
2014-04-02 13:47:29 -07:00
Preeti U Murthy
0888839c5b cpuidle/powernv: Parse device tree to setup idle states
Add deep idle states such as nap and fast sleep to the cpuidle state table
only if they are discovered from the device tree during cpuidle initialization.

Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-03-05 15:57:08 +11:00
Preeti U Murthy
0d94873011 cpuidle/powernv: Add "Fast-Sleep" CPU idle state
Fast sleep is one of the deep idle states on Power8 in which local timers of
CPUs stop. On PowerPC we do not have an external clock device which can
handle wakeup of such CPUs. Now that we have the support in the tick broadcast
framework for archs that do not sport such a device and the low level support
for fast sleep, enable it in the cpuidle framework on PowerNV.

Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-03-05 15:57:04 +11:00
Nicolas Pitre
591ac0cb01 cpuidle/powernv: Remove redundant cpuidle_idle_call()
The core idle loop now takes care of it. We need to add the runlatch
function calls to the idle routines which was earlier taken care of by
the arch specific idle routine.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Reviewed-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-pm@vger.kernel.org
Cc: linaro-kernel@lists.linaro.org
Link: http://lkml.kernel.org/n/tip-nr4mtbkkzf2oomaj85m24o7c@git.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-02-22 18:18:01 +01:00
Deepthi Dharwar
2c2e6ecfd0 powerpc/powernv/cpuidle: Back-end cpuidle driver for powernv platform.
Following patch ports the cpuidle framework for powernv
platform and also implements a cpuidle back-end powernv
idle driver calling on to power7_nap and snooze idle states.

Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-29 17:02:24 +11:00