summaryrefslogtreecommitdiffstats
path: root/arch/arm64/kernel/psci.c
AgeCommit message (Collapse)Author
2015-02-26arm64: psci: move psci firmware calls out of lineWill Deacon
An arm64 allmodconfig fails to build with GCC 5 due to __asmeq assertions in the PSCI firmware calling code firing due to mcount preambles breaking our assumptions about register allocation of function arguments: /tmp/ccDqJsJ6.s: Assembler messages: /tmp/ccDqJsJ6.s:60: Error: .err encountered /tmp/ccDqJsJ6.s:61: Error: .err encountered /tmp/ccDqJsJ6.s:62: Error: .err encountered /tmp/ccDqJsJ6.s:99: Error: .err encountered /tmp/ccDqJsJ6.s:100: Error: .err encountered /tmp/ccDqJsJ6.s:101: Error: .err encountered This patch fixes the issue by moving the PSCI calls out-of-line into their own assembly files, which are safe from the compiler's meddling fingers. Reported-by: Andy Whitcroft <apw@canonical.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-27arm64: kernel: remove ARM64_CPU_SUSPEND config optionLorenzo Pieralisi
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>
2014-12-16Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: "Given that my availability next week is likely to be poor, here are three arm64 fixes to resolve some issues introduced by features merged last week. I was going to wait until -rc1, but it doesn't make much sense to sit on fixes. Fix some fallout introduced during the merge window: - Build failure when PM_SLEEP is disabled but CPU_IDLE is enabled - Compiler warning from page table dumper w/ 48-bit VAs - Erroneous page table truncation in reported dump" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: mm: dump: don't skip final region arm64: mm: dump: fix shift warning arm64: psci: Fix build breakage without PM_SLEEP
2014-12-11arm64: psci: Fix build breakage without PM_SLEEPKrzysztof Kozlowski
Fix build failure of defconfig when PM_SLEEP is disabled (e.g. by disabling SUSPEND) and CPU_IDLE enabled: arch/arm64/kernel/psci.c:543:2: error: unknown field ‘cpu_suspend’ specified in initializer .cpu_suspend = cpu_psci_cpu_suspend, ^ arch/arm64/kernel/psci.c:543:2: warning: initialization from incompatible pointer type [enabled by default] arch/arm64/kernel/psci.c:543:2: warning: (near initialization for ‘cpu_psci_ops.cpu_prepare’) [enabled by default] make[1]: *** [arch/arm64/kernel/psci.o] Error 1 The cpu_operations.cpu_suspend field exists only if ARM64_CPU_SUSPEND is defined, not CPU_IDLE. Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-22Merge branch 'master' into for-3.19Tejun Heo
Pull in to receive 54ef6df3f3f1 ("rcu: Provide counterpart to rcu_dereference() for non-RCU situations"). Signed-off-by: Tejun Heo <tj@kernel.org>
2014-10-30arm64: psci: fix cpu_suspend to check idle state type for indexAmit Daniel Kachhap
This fix rectifies the psci cpu_suspend implementation to check the PSCI power state parameter type field associated with the requested idle state index. Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-10-29percpu: Convert remaining __get_cpu_var uses in 3.18-rcXChristoph Lameter
During the 3.18 merge period additional __get_cpu_var uses were added. The patch converts these to this_cpu_ptr(). Signed-off-by: Christoph Lameter <cl@linux.com> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Tejun Heo <tj@kernel.org>
2014-09-12arm64: add PSCI CPU_SUSPEND based cpu_suspend supportLorenzo Pieralisi
This patch implements the cpu_suspend cpu operations method through the PSCI CPU SUSPEND API. The PSCI implementation translates the idle state index passed by the cpu_suspend core call into a valid PSCI state according to the PSCI states initialized at boot through the cpu_init_idle() CPU operations hook. The PSCI CPU suspend operation hook checks if the PSCI state is a standby state. If it is, it calls the PSCI suspend implementation straight away, without saving any context. If the state is a power down state the kernel calls the __cpu_suspend API (that saves the CPU context) and passed the PSCI suspend finisher as a parameter so that PSCI can be called by the __cpu_suspend implementation after saving and flushing the context as last function before power down. For power down states, entry point is set to cpu_resume physical address, that represents the default kernel execution address following a CPU reset. Reviewed-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> 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>
2014-07-18arm64: kernel: add __init marker to PSCI init functionsLorenzo Pieralisi
PSCI init functions must be marked as __init so that they are freed by the kernel upon boot. This patch marks the PSCI init functions as such since they need not be persistent in the kernel address space after the kernel has booted. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-07-18arm64: kernel: enable PSCI cpu operations on UP systemsLorenzo Pieralisi
PSCI CPU operations have to be enabled on UP kernels so that calls like eg cpu_suspend can be made functional on UP too. This patch reworks the PSCI CPU operations so that they can be enabled on UP systems. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-15ARM: Check if a CPU has gone offlineAshwin Chaugule
PSCIv0.2 adds a new function called AFFINITY_INFO, which can be used to query if a specified CPU has actually gone offline. Calling this function via cpu_kill ensures that a CPU has quiesced after a call to cpu_die. This helps prevent the CPU from doing arbitrary bad things when data or instructions are clobbered (as happens with kexec) in the window between a CPU announcing that it is dead and said CPU leaving the kernel. Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Rob Herring <robh@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-15PSCI: Add initial support for PSCIv0.2 functionsAshwin Chaugule
The PSCIv0.2 spec defines standard values of function IDs and introduces a few new functions. Detect version of PSCI and appropriately select the right PSCI functions. Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Reviewed-by: Rob Herring <robh@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2014-02-28arm64: remove return value form psci_init()Vladimir Murzin
psci_init() is written to return err code if something goes wrong. However, the single user, setup_arch(), doesn't care about it. Moreover, every error path is supplied with a clear message which is enough for pleasant debugging. Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-02-28arm64: remove redundant "psci:" prefixesVladimir Murzin
Since 652af899799354049b273af897b798b8f03fdd88 "arm64: factor out spin-table boot method" psci prefix's been introduced. We have a common pr_fmt, so clean them up. Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-10-25arm64: add PSCI CPU_OFF-based hotplug supportMark Rutland
This patch adds support for using PSCI CPU_OFF calls for CPU hotplug. With this code it is possible to hot unplug CPUs with "psci" as their boot-method, as long as there's an appropriate cpu_off function id specified in the psci node. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-10-25arm64: factor out spin-table boot methodMark Rutland
The arm64 kernel has an internal holding pen, which is necessary for some systems where we can't bring CPUs online individually and must hold multiple CPUs in a safe area until the kernel is able to handle them. The current SMP infrastructure for arm64 is closely coupled to this holding pen, and alternative boot methods must launch CPUs into the pen, where they sit before they are launched into the kernel proper. With PSCI (and possibly other future boot methods), we can bring CPUs online individually, and need not perform the secondary_holding_pen dance. Instead, this patch factors the holding pen management code out to the spin-table boot method code, as it is the only boot method requiring the pen. A new entry point for secondaries, secondary_entry is added for other boot methods to use, which bypasses the holding pen and its associated overhead when bringing CPUs online. The smp.pen.text section is also removed, as the pen can live in head.text without problem. The cpu_operations structure is extended with two new functions, cpu_boot and cpu_postboot, for bringing a cpu into the kernel and performing any post-boot cleanup required by a bootmethod (e.g. resetting the secondary_holding_pen_release to INVALID_HWID). Documentation is added for cpu_operations. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-10-25arm64: reorganise smp_enable_opsMark Rutland
For hotplug support, we're going to want a place to store operations that do more than bring CPUs online, and it makes sense to group these with our current smp_enable_ops. For cpuidle support, we'll want to group additional functions, and we may want them even for UP kernels. This patch renames smp_enable_ops to the more general cpu_operations, and pulls the definitions out of smp code such that they can be used in UP kernels. While we're at it, fix up instances of the cpu parameter to be an unsigned int, drop the init markings and rename the *_cpu functions to cpu_* to reduce future churn when cpu_operations is extended. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-10-25arm64: unify smp_psci.c and psci.cMark Rutland
The functions in psci.c are only used from smp_psci.c, and smp_psci cannot function without psci.c. Additionally psci.c is built when !SMP, where it's expected that cpu_suspend may be useful. This patch unifies the two files, removing pointless duplication and paving the way for PSCI support in UP systems. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-01-29arm64: psci: add support for PSCI invocations from the kernelWill Deacon
This patch adds support for the Power State Coordination Interface defined by ARM, allowing Linux to request CPU-centric power-management operations from firmware implementing the PSCI protocol. Signed-off-by: Will Deacon <will.deacon@arm.com> [Marc: s/u32/u64/ in the relevant spots, and switch from an initcall to an simpler init function] Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>