diff options
| author | Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com> | 2013-08-23 15:53:15 +0100 |
|---|---|---|
| committer | Emad Mir <emir@nvidia.com> | 2014-06-30 11:16:46 -0700 |
| commit | 1d4720a1840ed9f73bafb31447535b4bd3bd2b8d (patch) | |
| tree | 68c6d4d3b22e3b0f92a64c9ec6c2b1ad00edb5c1 /arch/arm/include | |
| parent | 2c5b4fdd7b2887adbab8b28a22e07eaae9110cbc (diff) | |
drivers: clocksource: add CPU PM notifier for ARM architected timer
Few control settings done in architected timer as part of initialisation
can be lost when CPU enters deeper power states. They need to be
restored when the CPU is (warm)reset again.
This patch adds CPU PM notifiers to save the counter control register
when entering low power modes and restore it when CPU exits low power.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
Change-Id: I0bad683961e4b72835ad40edf2c9ac9e0f78fad0
Reviewed-on: http://git-master/r/350844
Reviewed-by: Bo Yan <byan@nvidia.com>
Tested-by: Bo Yan <byan@nvidia.com>
Reviewed-on: http://git-master/r/427526
Tested-by: Andrey Trachenko <atrachenko@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>
Diffstat (limited to 'arch/arm/include')
| -rw-r--r-- | arch/arm/include/asm/arch_timer.h | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/arch/arm/include/asm/arch_timer.h b/arch/arm/include/asm/arch_timer.h index d138aaed8382..9d3221ca1518 100644 --- a/arch/arm/include/asm/arch_timer.h +++ b/arch/arm/include/asm/arch_timer.h @@ -87,11 +87,21 @@ static inline u64 arch_counter_get_cntvct(void) return cval; } -static inline void __cpuinit arch_counter_set_user_access(void) +static inline u32 arch_timer_get_cntkctl(void) { u32 cntkctl; - asm volatile("mrc p15, 0, %0, c14, c1, 0" : "=r" (cntkctl)); + return cntkctl; +} + +static inline void arch_timer_set_cntkctl(u32 cntkctl) +{ + asm volatile("mcr p15, 0, %0, c14, c1, 0" : : "r" (cntkctl)); +} + +static inline void arch_counter_set_user_access(void) +{ + u32 cntkctl = arch_timer_get_cntkctl(); /* Disable user access to the timers and the physical counter */ /* Also disable virtual event stream */ @@ -103,7 +113,7 @@ static inline void __cpuinit arch_counter_set_user_access(void) /* Enable user access to the virtual counter */ cntkctl |= ARCH_TIMER_USR_VCT_ACCESS_EN; - asm volatile("mcr p15, 0, %0, c14, c1, 0" : : "r" (cntkctl)); + arch_timer_set_cntkctl(cntkctl); } #endif |