diff options
| author | Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> | 2013-09-04 10:55:17 +0100 |
|---|---|---|
| committer | Ishan Mittal <imittal@nvidia.com> | 2014-04-30 15:06:24 +0530 |
| commit | 324fad69a7ccf9c1aad0f4c5760e6aac7d1aed9c (patch) | |
| tree | 137d53e1f7b82df3d047c82aa858265146b90298 | |
| parent | f6b5ba02009c744edea3438c4ef832f9ca10774e (diff) | |
arm64: enable generic clockevent broadcast
On platforms with power management capabilities, timers that are shut
down when a CPU enters deep C-states must be emulated using an always-on
timer and a timer IPI to relay the timer IRQ to target CPUs on an SMP
system.
This patch enables the generic clockevents broadcast infrastructure for
arm64, by providing the required Kconfig entries and adding the timer
IPI infrastructure.
Conflicts:
arch/arm64/kernel/smp.c
Change-Id: I870b309fc3a68832d6ff471a3ef8313058ba9f82
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
(cherry picked from commit 1f85008e74768a88e1ddb96cc1fe45bb2378166c)
Signed-off-by: Ishan Mittal <imittal@nvidia.com>
| -rw-r--r-- | arch/arm64/Kconfig | 2 | ||||
| -rw-r--r-- | arch/arm64/include/asm/hardirq.h | 2 | ||||
| -rw-r--r-- | arch/arm64/kernel/smp.c | 16 |
3 files changed, 19 insertions, 1 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 6abd7f9c1665..abf025d31706 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -3,6 +3,7 @@ config ARM64 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE select ARCH_HAVE_CUSTOM_GPIO_H select ARCH_USE_CMPXCHG_LOCKREF + select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST select ARCH_WANT_OPTIONAL_GPIOLIB select ARCH_WANT_COMPAT_IPC_PARSE_VERSION select ARCH_WANT_FRAME_POINTERS @@ -13,6 +14,7 @@ config ARM64 # select COMMON_CLK select CPU_PM if (SUSPEND || CPU_IDLE) select GENERIC_CLOCKEVENTS + select GENERIC_CLOCKEVENTS_BROADCAST if SMP select GENERIC_IOMAP select GENERIC_IRQ_PROBE select GENERIC_IRQ_SHOW diff --git a/arch/arm64/include/asm/hardirq.h b/arch/arm64/include/asm/hardirq.h index ae4801d77514..0be67821f9ce 100644 --- a/arch/arm64/include/asm/hardirq.h +++ b/arch/arm64/include/asm/hardirq.h @@ -20,7 +20,7 @@ #include <linux/threads.h> #include <asm/irq.h> -#define NR_IPI 5 +#define NR_IPI 6 typedef struct { unsigned int __softirq_pending; diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index cdb2b0eb8448..fed9d17a8866 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -62,6 +62,7 @@ enum ipi_msg_type { IPI_CALL_FUNC_SINGLE, IPI_CPU_STOP, IPI_WAKEUP, + IPI_TIMER, }; static DEFINE_RAW_SPINLOCK(boot_lock); @@ -597,6 +598,7 @@ static const char *ipi_types[NR_IPI] = { S(IPI_CALL_FUNC_SINGLE, "Single function call interrupts"), S(IPI_CPU_STOP, "CPU stop interrupts"), S(IPI_WAKEUP, "CPU wakeup interrupts"), + S(IPI_TIMER, "Timer broadcast interrupts"), }; void show_ipi_list(struct seq_file *p, int prec) @@ -684,6 +686,13 @@ void handle_IPI(int ipinr, struct pt_regs *regs) case IPI_WAKEUP: break; +#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST + case IPI_TIMER: + irq_enter(); + tick_receive_broadcast(); + irq_exit(); + break; +#endif default: pr_crit("CPU%u: Unknown IPI message 0x%x\n", cpu, ipinr); @@ -697,6 +706,13 @@ void smp_send_reschedule(int cpu) smp_cross_call(cpumask_of(cpu), IPI_RESCHEDULE); } +#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST +void tick_broadcast(const struct cpumask *mask) +{ + smp_cross_call(mask, IPI_TIMER); +} +#endif + void smp_send_stop(void) { unsigned long timeout; |