linux-dev/drivers/idle, branch master

intel_idle: Add AlderLake-N support

2022-09-21T18:33:49Z

Similar to the other other AlderLake platforms, the C1 and C1E states on ADL-N are mutually exclusive. Only one of them can be enabled at a time. C1E is preferred on ADL-N for better energy efficiency. C6S is also supported on this platform. Its latency is far bigger than C6, but really close to C8 (PC8), thus it is not exposed as a separate state. Suggested-by: Baieswara Reddy Sagili Suggested-by: Vinay Kumar Signed-off-by: Zhang Rui [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki

intel_idle: move from strlcpy() with unused retval to strscpy()

2022-08-31T19:12:03Z

Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Signed-off-by: Wolfram Sang Signed-off-by: Rafael J. Wysocki

Merge tag 'pm-5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2022-08-02T18:17:00Z

Pull power management updates from Rafael Wysocki: "These are mostly minor improvements all over including new CPU IDs for the Intel RAPL driver, an Energy Model rework to use micro-Watt as the power unit, cpufreq fixes and cleanus, cpuidle updates, devfreq updates, documentation cleanups and a new version of the pm-graph suite of utilities. Specifics: - Make cpufreq_show_cpus() more straightforward (Viresh Kumar). - Drop unnecessary CPU hotplug locking from store() used by cpufreq sysfs attributes (Viresh Kumar). - Make the ACPI cpufreq driver support the boost control interface on Zhaoxin/Centaur processors (Tony W Wang-oc). - Print a warning message on attempts to free an active cpufreq policy which should never happen (Viresh Kumar). - Fix grammar in the Kconfig help text for the loongson2 cpufreq driver (Randy Dunlap). - Use cpumask_var_t for an on-stack CPU mask in the ondemand cpufreq governor (Zhao Liu). - Add trace points for guest_halt_poll_ns grow/shrink to the haltpoll cpuidle driver (Eiichi Tsukata). - Modify intel_idle to treat C1 and C1E as independent idle states on Sapphire Rapids (Artem Bityutskiy). - Extend support for wakeirq to callback wrappers used during system suspend and resume (Ulf Hansson). - Defer waiting for device probe before loading a hibernation image till the first actual device access to avoid possible deadlocks reported by syzbot (Tetsuo Handa). - Unify device_init_wakeup() for PM_SLEEP and !PM_SLEEP (Bjorn Helgaas). - Add Raptor Lake-P to the list of processors supported by the Intel RAPL driver (George D Sworo). - Add Alder Lake-N and Raptor Lake-P to the list of processors for which Power Limit4 is supported in the Intel RAPL driver (Sumeet Pawnikar). - Make pm_genpd_remove() check genpd_debugfs_dir against NULL before attempting to remove it (Hsin-Yi Wang). - Change the Energy Model code to represent power in micro-Watts and adjust its users accordingly (Lukasz Luba). - Add new devfreq driver for Mediatek CCI (Cache Coherent Interconnect) (Johnson Wang). - Convert the Samsung Exynos SoC Bus bindings to DT schema of exynos-bus.c (Krzysztof Kozlowski). - Address kernel-doc warnings by adding the description for unused function parameters in devfreq core (Mauro Carvalho Chehab). - Use NULL to pass a null pointer rather than zero according to the function propotype in imx-bus.c (Colin Ian King). - Print error message instead of error interger value in tegra30-devfreq.c (Dmitry Osipenko). - Add checks to prevent setting negative frequency QoS limits for CPUs (Shivnandan Kumar). - Update the pm-graph suite of utilities to the latest revision 5.9 including multiple improvements (Todd Brandt). - Drop pme_interrupt reference from the PCI power management documentation (Mario Limonciello)" * tag 'pm-5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (27 commits) powercap: RAPL: Add Power Limit4 support for Alder Lake-N and Raptor Lake-P PM: QoS: Add check to make sure CPU freq is non-negative PM: hibernate: defer device probing when resuming from hibernation intel_idle: make SPR C1 and C1E be independent cpufreq: ondemand: Use cpumask_var_t for on-stack cpu mask cpufreq: loongson2: fix Kconfig "its" grammar pm-graph v5.9 cpufreq: Warn users while freeing active policy cpufreq: scmi: Support the power scale in micro-Watts in SCMI v3.1 firmware: arm_scmi: Get detailed power scale from perf Documentation: EM: Switch to micro-Watts scale PM: EM: convert power field to micro-Watts precision and align drivers PM / devfreq: tegra30: Add error message for devm_devfreq_add_device() PM / devfreq: imx-bus: use NULL to pass a null pointer rather than zero PM / devfreq: shut up kernel-doc warnings dt-bindings: interconnect: samsung,exynos-bus: convert to dtschema PM / devfreq: mediatek: Introduce MediaTek CCI devfreq driver dt-bindings: interconnect: Add MediaTek CCI dt-bindings PM: domains: Ensure genpd_debugfs_dir exists before remove PM: runtime: Extend support for wakeirq for force_suspend|resume ...

Merge tag 'x86_fpu_for_v6.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2022-08-01T16:36:18Z

Pull x86 fpu update from Borislav Petkov: - Add machinery to initialize AMX register state in order for AMX-capable CPUs to be able to enter deeper low-power state * tag 'x86_fpu_for_v6.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: intel_idle: Add a new flag to initialize the AMX state x86/fpu: Add a helper to prepare AMX state for low-power CPU idle

Merge back cpuidle material for 5.20.

2022-07-29T15:15:30Z

intel_idle: make SPR C1 and C1E be independent

2022-07-25T18:40:29Z

This patch partially reverts the changes made by the following commit: da0e58c038e6 intel_idle: add 'preferred_cstates' module argument As that commit describes, on early Sapphire Rapids Xeon platforms the C1 and C1E states were mutually exclusive, so that users could only have either C1 and C6, or C1E and C6. However, Intel firmware engineers managed to remove this limitation and make C1 and C1E to be completely independent, just like on previous Xeon platforms. Therefore, this patch: * Removes commentary describing the old, and now non-existing SPR C1E limitation. * Marks SPR C1E as available by default. * Removes the 'preferred_cstates' parameter handling for SPR. Both C1 and C1E will be available regardless of 'preferred_cstates' value. We expect that all SPR systems are shipping with new firmware, which includes the C1/C1E improvement. Cc: v5.18+ # v5.18+ Signed-off-by: Artem Bityutskiy Signed-off-by: Rafael J. Wysocki

intel_idle: Fix false positive RCU splats due to incorrect hardirqs state

2022-07-25T17:39:07Z

Commit 32d4fd5751ea ("cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE") uses raw_local_irq_enable/local_irq_disable() around call to __intel_idle() in intel_idle_irq(). With interrupt enabled, timer tick interrupt can happen and a subsequently call to __do_softirq() may change the lockdep hardirqs state of a debug kernel back to 'on'. This will result in a mismatch between the cpu hardirqs state (off) and the lockdep hardirqs state (on) causing a number of false positive "WARNING: suspicious RCU usage" splats. Fix that by using local_irq_disable() to disable interrupt in intel_idle_irq(). Fixes: 32d4fd5751ea ("cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE") Signed-off-by: Waiman Long Cc: 5.16+ # 5.16+ Signed-off-by: Rafael J. Wysocki

intel_idle: Add a new flag to initialize the AMX state

2022-07-19T17:17:28Z

The non-initialized AMX state can be the cause of C-state demotion from C6 to C1E. This low-power idle state may improve power savings and thus result in a higher available turbo frequency budget. This behavior is implementation-specific. Initialize the state for the C6 entrance of Sapphire Rapids as needed. Suggested-by: Peter Zijlstra (Intel) Signed-off-by: Dave Hansen Signed-off-by: Chang S. Bae Signed-off-by: Borislav Petkov Acked-by: Rafael J. Wysocki Tested-by: Zhang Rui Link: https://lkml.kernel.org/r/20220614164116.5196-1-chang.seok.bae@intel.com

intel_idle: Disable IBRS during long idle

2022-06-27T08:33:59Z

Having IBRS enabled while the SMT sibling is idle unnecessarily slows down the running sibling. OTOH, disabling IBRS around idle takes two MSR writes, which will increase the idle latency. Therefore, only disable IBRS around deeper idle states. Shallow idle states are bounded by the tick in duration, since NOHZ is not allowed for them by virtue of their short target residency. Only do this for mwait-driven idle, since that keeps interrupts disabled across idle, which makes disabling IBRS vs IRQ-entry a non-issue. Note: C6 is a random threshold, most importantly C1 probably shouldn't disable IBRS, benchmarking needed. Suggested-by: Tim Chen Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Borislav Petkov Reviewed-by: Josh Poimboeuf Signed-off-by: Borislav Petkov

cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE

2022-06-08T16:05:45Z

Commit c227233ad64c ("intel_idle: enable interrupts before C1 on Xeons") wrecked intel_idle in two ways: - must not have tracing in idle functions - must return with IRQs disabled Additionally, it added a branch for no good reason. Fixes: c227233ad64c ("intel_idle: enable interrupts before C1 on Xeons") Signed-off-by: Peter Zijlstra (Intel) [ rjw: Moved the intel_idle() kerneldoc comment next to the function ] Cc: 5.16+ # 5.16+ Signed-off-by: Rafael J. Wysocki