ARM: perf: save/restore pmu registers in pm notifier

This adds core support for saving and restoring CPU PMU registers
for suspend/resume support i.e. deeper C-states in cpuidle terms.
This patch adds support only to ARMv7 PMU registers save/restore.
It needs to be extended to xscale and ARMv6 if needed.

Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/arch/arm/include/asm/pmu.h b/arch/arm/include/asm/pmu.h
index 3713e57a467..0cd7824ca76 100644
--- a/arch/arm/include/asm/pmu.h
+++ b/arch/arm/include/asm/pmu.h
@@ -62,6 +62,15 @@ struct pmu_hw_events {
 	raw_spinlock_t		pmu_lock;
 };
 
+struct cpupmu_regs {
+	u32 pmc;
+	u32 pmcntenset;
+	u32 pmuseren;
+	u32 pmintenset;
+	u32 pmxevttype[8];
+	u32 pmxevtcnt[8];
+};
+
 struct arm_pmu {
 	struct pmu	pmu;
 	cpumask_t	active_irqs;
@@ -82,6 +91,8 @@ struct arm_pmu {
 	int		(*request_irq)(struct arm_pmu *, irq_handler_t handler);
 	void		(*free_irq)(struct arm_pmu *);
 	int		(*map_event)(struct perf_event *event);
+	void		(*save_regs)(struct arm_pmu *, struct cpupmu_regs *);
+	void		(*restore_regs)(struct arm_pmu *, struct cpupmu_regs *);
 	int		num_events;
 	atomic_t	active_events;
 	struct mutex	reserve_mutex;