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2016-07-15cpuidle/powernv: Add support for POWER ISA v3 idle statesShreyas B. Prabhu
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>
2016-07-15cpuidle/powernv: cleanup cpuidle-powernv.cShreyas B. Prabhu
- 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>
2016-07-15cpuidle/powernv: Use CPUIDLE_STATE_MAX instead of MAX_POWERNV_IDLE_STATESShreyas B. Prabhu
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>
2015-12-17powerpc/powernv: remove FW_FEATURE_OPALv3 and just use FW_FEATURE_OPALStewart Smith
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>
2015-06-26tick/idle/powerpc: Do not register idle states with CPUIDLE_FLAG_TIMER_STOP ↵preeti
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>
2015-06-22cpuidle: powernv/pseries: Auto-promotion of snooze to deeper idle stateShilpasri G Bhat
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>
2015-02-19cpuidle: powernv: Avoid endianness conversions while parsing DTPreeti U Murthy
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>
2015-02-18cpuidle: powernv: Read target_residency value of idle states from DT if ↵Preeti U Murthy
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>
2014-12-19Merge tag 'powerpc-3.19-2' of ↵Linus Torvalds
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
2014-12-15powernv/cpuidle: Redesign idle states managementShreyas B. Prabhu
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>
2014-12-15powerpc/powernv: Enable Offline CPUs to enter deep idle statesShreyas B. Prabhu
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>
2014-11-12cpuidle: Invert CPUIDLE_FLAG_TIME_VALID logicDaniel Lezcano
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>
2014-10-21cpuidle: powernv: Populate cpuidle state details by querying the device-treePreeti U. Murthy
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>
2014-08-05powerpc/cpuidle: Fix parsing of idle state flags from device-treeVaidyanathan Srinivasan
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>
2014-06-11powerpc/cpuidle: Only clear LPCR decrementer wakeup bit on fast sleep entryMichael Neuling
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>
2014-04-02Merge branch 'powernv-cpuidle' of ↵Linus Torvalds
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
2014-03-05cpuidle/powernv: Parse device tree to setup idle statesPreeti U Murthy
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>
2014-03-05cpuidle/powernv: Add "Fast-Sleep" CPU idle statePreeti U Murthy
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>
2014-02-22cpuidle/powernv: Remove redundant cpuidle_idle_call()Nicolas Pitre
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>
2014-01-29powerpc/powernv/cpuidle: Back-end cpuidle driver for powernv platform.Deepthi Dharwar
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>