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2021-05-06arm64: kernel: Update the stale commentShaokun Zhang1-1/+1
Commit af391b15f7b5 ("arm64: kernel: rename __cpu_suspend to keep it aligned with arm") has used @index instead of @arg, but the comment is stale, update it. Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Link: https://lore.kernel.org/r/1620280462-21937-1-git-send-email-zhangshaokun@hisilicon.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-24arm64: Introduce get_cpu_ops() helper functionGavin Shan1-4/+5
This introduces get_cpu_ops() to return the CPU operations according to the given CPU index. For now, it simply returns the @cpu_ops[cpu] as before. Also, helper function __cpu_try_die() is introduced to be shared by cpu_die() and ipi_cpu_crash_stop(). So it shouldn't introduce any functional changes. Signed-off-by: Gavin Shan <gshan@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com>
2019-08-09PSCI: cpuidle: Refactor CPU suspend power_state parameter handlingLorenzo Pieralisi1-4/+45
Current PSCI code handles idle state entry through the psci_cpu_suspend_enter() API, that takes an idle state index as a parameter and convert the index into a previously initialized power_state parameter before calling the PSCI.CPU_SUSPEND() with it. This is unwieldly, since it forces the PSCI firmware layer to keep track of power_state parameter for every idle state so that the index->power_state conversion can be made in the PSCI firmware layer instead of the CPUidle driver implementations. Move the power_state handling out of drivers/firmware/psci into the respective ACPI/DT PSCI CPUidle backends and convert the psci_cpu_suspend_enter() API to get the power_state parameter as input, which makes it closer to its firmware interface PSCI.CPU_SUSPEND() API. A notable side effect is that the PSCI ACPI/DT CPUidle backends now can directly handle (and if needed update) power_state parameters before handing them over to the PSCI firmware interface to trigger PSCI.CPU_SUSPEND() calls. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-09ARM: psci: cpuidle: Enable PSCI CPUidle driverLorenzo Pieralisi1-3/+4
Allow selection of the PSCI CPUidle in the kernel by updating the respective Kconfig entry. Remove PSCI callbacks from ARM/ARM64 generic CPU ops to prevent the PSCI idle driver from clashing with the generic ARM CPUidle driver initialization, that relies on CPU ops to initialize and enter idle states. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Cc: Will Deacon <will@kernel.org> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Signed-off-by: Will Deacon <will@kernel.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner1-4/+1
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-02ARM64 / cpuidle: Use new cpuidle macro for entering retention statePrashanth Prakash1-1/+7
CPU_PM_CPU_IDLE_ENTER_RETENTION skips calling cpu_pm_enter() and cpu_pm_exit(). By not calling cpu_pm functions in idle entry/exit paths we can reduce the latency involved in entering and exiting the low power idle state. On ARM64 based Qualcomm server platform we measured below overhead for calling cpu_pm_enter and cpu_pm_exit for retention states. workload: stress --hdd #CPUs --hdd-bytes 32M -t 30 Average overhead of cpu_pm_enter - 1.2us Average overhead of cpu_pm_exit - 3.1us Acked-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-10arm64: kernel: Update kerneldoc for cpu_suspend() renameGeert Uytterhoeven1-1/+1
Commit af391b15f7b56ce1 ("arm64: kernel: rename __cpu_suspend to keep it aligned with arm") renamed cpu_suspend() to arm_cpuidle_suspend(), but forgot to update the kerneldoc header. Fixes: af391b15f7b56ce1 ("arm64: kernel: rename __cpu_suspend to keep it aligned with arm") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-07-22arm64: add support for ACPI Low Power Idle(LPI)Sudeep Holla1-0/+18
This patch adds appropriate callbacks to support ACPI Low Power Idle (LPI) on ARM64. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-22arm64: cpuidle: drop __init section marker to arm_cpuidle_initSudeep Holla1-1/+1
Commit ea389daa7fd9 (arm64: cpuidle: add __init section marker to arm_cpuidle_init) added the __init annotation to arm_cpuidle_init as it was not needed after booting which was correct at that time. However with the introduction of ACPI LPI support, this will be used from cpuhotplug path in ACPI processor driver. This patch drops the __init annotation from arm_cpuidle_init to avoid the following warning: WARNING: vmlinux.o(.text+0x113c8): Section mismatch in reference from the function acpi_processor_ffh_lpi_probe() to the function .init.text:arm_cpuidle_init() The function acpi_processor_ffh_lpi_probe() references the function __init arm_cpuidle_init(). This is often because acpi_processor_ffh_lpi_probe() lacks a __init annotation or the annotation of arm_cpuidle_init is wrong. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-04-13arm64: cpuidle: make arm_cpuidle_suspend() a bit more efficientJisheng Zhang1-7/+2
Currently, we check two pointers: cpu_ops and cpu_suspend on every idle state entry. These pointers check can be avoided: If cpu_ops has not been registered, arm_cpuidle_init() will return -EOPNOTSUPP, so arm_cpuidle_suspend() will never have chance to run. In other word, the cpu_ops check can be avoid. Similarly, the cpu_suspend check could be avoided in this hot path by moving it into arm_cpuidle_init(). I measured the 4096 * time from arm_cpuidle_suspend entry point to the cpu_psci_cpu_suspend entry point. HW platform is Marvell BG4CT STB board. 1. only one shell, no other process, hot-unplug secondary cpus, execute the following cmd while true do sleep 0.2 done before the patch: 1581220ns after the patch: 1579630ns reduced by 0.1% 2. only one shell, no other process, hot-unplug secondary cpus, execute the following cmd while true do md5sum /tmp/testfile sleep 0.2 done NOTE: the testfile size should be larger than L1+L2 cache size before the patch: 1961960ns after the patch: 1912500ns reduced by 2.5% So the more complex the system load, the bigger the improvement. Signed-off-by: Jisheng Zhang <jszhang@marvell.com> Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-02arm64: cpuidle: add __init section marker to arm_cpuidle_initJisheng Zhang1-1/+1
It is not needed after booting, this patch moves the arm_cpuidle_init() function to the __init section. Signed-off-by: Jisheng Zhang <jszhang@marvell.com> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-06-19arm64: kernel: rename __cpu_suspend to keep it aligned with armSudeep Holla1-2/+2
This patch renames __cpu_suspend to cpu_suspend so that it's aligned with ARM32. It also removes the redundant wrapper created. This is in preparation to implement generic PSCI system suspend using the cpu_{suspend,resume} which now has the same interface on both ARM and ARM64. Cc: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Reviewed-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-05-19ARM64: kernel: make cpu_ops hooks DT agnosticLorenzo Pieralisi1-6/+1
ARM64 CPU operations such as cpu_init and cpu_init_idle take a struct device_node pointer as a parameter, which corresponds to the device tree node of the logical cpu on which the operation has to be applied. With the advent of ACPI on arm64, where MADT static table entries are used to initialize cpus, the device tree node parameter in cpu_ops hooks become useless when booting with ACPI, since in that case cpu device tree nodes are not present and can not be used for cpu initialization. The current cpu_init hook requires a struct device_node pointer parameter because it is called while parsing the device tree to initialize CPUs, when the cpu_logical_map (that is used to match a cpu node reg property to a device tree node) for a given logical cpu id is not set up yet. This means that the cpu_init hook cannot rely on the of_get_cpu_node function to retrieve the device tree node corresponding to the logical cpu id passed in as parameter, so the cpu device tree node must be passed in as a parameter to fix this catch-22 dependency cycle. This patch reshuffles the cpu_logical_map initialization code so that the cpu_init cpu_ops hook can safely use the of_get_cpu_node function to retrieve the cpu device tree node, removing the need for the device tree node pointer parameter. In the process, the patch removes device tree node parameters from all cpu_ops hooks, in preparation for SMP DT/ACPI cpus initialization consolidation. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Hanjun Guo <hanjun.guo@linaro.org> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Mark Rutland <mark.rutland@arm.com> [DT] Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-03-24ARM64: cpuidle: Rename cpu_init_idle to a common function nameDaniel Lezcano1-1/+1
With this change the cpuidle-arm64.c file calls the same function name for both ARM and ARM64. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Kevin Hilman <khilman@linaro.org> Acked-by: Rob Herring <robherring2@gmail.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
2015-01-27arm64: kernel: remove ARM64_CPU_SUSPEND config optionLorenzo Pieralisi1-0/+20
ARM64_CPU_SUSPEND config option was introduced to make code providing context save/restore selectable only on platforms requiring power management capabilities. Currently ARM64_CPU_SUSPEND depends on the PM_SLEEP config option which in turn is set by the SUSPEND config option. The introduction of CPU_IDLE for arm64 requires that code configured by ARM64_CPU_SUSPEND (context save/restore) should be compiled in in order to enable the CPU idle driver to rely on CPU operations carrying out context save/restore. The ARM64_CPUIDLE config option (ARM64 generic idle driver) is therefore forced to select ARM64_CPU_SUSPEND, even if there may be (ie PM_SLEEP) failed dependencies, which is not a clean way of handling the kernel configuration option. For these reasons, this patch removes the ARM64_CPU_SUSPEND config option and makes the context save/restore dependent on CPU_PM, which is selected whenever either SUSPEND or CPU_IDLE are configured, cleaning up dependencies in the process. This way, code previously configured through ARM64_CPU_SUSPEND is compiled in whenever a power management subsystem requires it to be present in the kernel (SUSPEND || CPU_IDLE), which is the behaviour expected on ARM64 kernels. The cpu_suspend and cpu_init_idle CPU operations are added only if CPU_IDLE is selected, since they are CPU_IDLE specific methods and should be grouped and defined accordingly. PSCI CPU operations are updated to reflect the introduced changes. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Will Deacon <will.deacon@arm.com> Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-09-12arm64: kernel: introduce cpu_init_idle CPU operationLorenzo Pieralisi1-0/+31
The CPUidle subsystem on ARM64 machines requires the idle states implementation back-end to initialize idle states parameter upon boot. This patch adds a hook in the CPU operations structure that should be initialized by the CPU operations back-end in order to provide a function that initializes cpu idle states. This patch also adds the infrastructure to arm64 kernel required to export the CPU operations based initialization interface, so that drivers (ie CPUidle) can use it when they are initialized at probe time. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>