From 0583fe478a7d93be2c814b7e50d6e81c287edfe8 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Wed, 10 Apr 2013 18:27:51 -0500 Subject: ARM: convert arm/arm64 arch timer to use CLKSRC_OF init This converts arm and arm64 to use CLKSRC_OF DT based initialization for the arch timer. A new function arch_timer_arch_init is added to allow for arch specific setup. This has a side effect of enabling sched_clock on omap5 and exynos5. There should not be any reason not to use the arch timers for sched_clock. Signed-off-by: Rob Herring Cc: Russell King Cc: Kukjin Kim Cc: Tony Lindgren Cc: Simon Horman Cc: Magnus Damm Cc: Catalin Marinas Cc: Will Deacon Cc: John Stultz Cc: Thomas Gleixner Cc: linux-samsung-soc@vger.kernel.org Cc: linux-omap@vger.kernel.org Cc: linux-sh@vger.kernel.org Acked-by: Santosh Shilimkar --- drivers/clocksource/Kconfig | 1 + drivers/clocksource/arm_arch_timer.c | 23 +++++++++-------------- 2 files changed, 10 insertions(+), 14 deletions(-) (limited to 'drivers/clocksource') diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index e507ab7df60b..d98e7e1ee594 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -62,6 +62,7 @@ config CLKSRC_DBX500_PRCMU_SCHED_CLOCK config ARM_ARCH_TIMER bool + select CLKSRC_OF if OF config CLKSRC_METAG_GENERIC def_bool y if METAG diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index d7ad425ab9b3..122ff05628b5 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -337,22 +337,14 @@ out: return err; } -static const struct of_device_id arch_timer_of_match[] __initconst = { - { .compatible = "arm,armv7-timer", }, - { .compatible = "arm,armv8-timer", }, - {}, -}; - -int __init arch_timer_init(void) +static void __init arch_timer_init(struct device_node *np) { - struct device_node *np; u32 freq; int i; - np = of_find_matching_node(NULL, arch_timer_of_match); - if (!np) { - pr_err("arch_timer: can't find DT node\n"); - return -ENODEV; + if (arch_timer_get_rate()) { + pr_warn("arch_timer: multiple nodes in dt, skipping\n"); + return; } /* Try to determine the frequency from the device tree or CNTFRQ */ @@ -378,7 +370,7 @@ int __init arch_timer_init(void) if (!arch_timer_ppi[PHYS_SECURE_PPI] || !arch_timer_ppi[PHYS_NONSECURE_PPI]) { pr_warn("arch_timer: No interrupt available, giving up\n"); - return -EINVAL; + return; } } @@ -387,5 +379,8 @@ int __init arch_timer_init(void) else arch_timer_read_counter = arch_counter_get_cntpct; - return arch_timer_register(); + arch_timer_register(); + arch_timer_arch_init(); } +CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_init); +CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_init); -- cgit v1.2.3 From f31c2f1c68aff83277eddc6798adf3438e9c680a Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Wed, 17 Apr 2013 16:26:18 -0700 Subject: ARM: arch_timer: Silence debug preempt warnings Hot-plugging with CONFIG_DEBUG_PREEMPT=y on a device with arm architected timers causes a slew of "using smp_processor_id() in preemptible" warnings: BUG: using smp_processor_id() in preemptible [00000000] code: sh/111 caller is arch_timer_cpu_notify+0x14/0xc8 This happens because sometimes the cpu notifier, arch_timer_cpu_notify(), is called in preemptible context and other times in non-preemptible context but we use this_cpu_ptr() to retrieve the clockevent in all cases. We're only going to actually use the pointer in non-preemptible context though, so push the this_cpu_ptr() access down into the cases to force the checks to occur only in non-preemptible contexts. Cc: John Stultz Cc: Thomas Gleixner Cc: Mark Rutland Acked-by: Marc Zyngier Signed-off-by: Stephen Boyd Signed-off-by: Olof Johansson --- drivers/clocksource/arm_arch_timer.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'drivers/clocksource') diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 122ff05628b5..a2b254189782 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -248,14 +248,16 @@ static void __cpuinit arch_timer_stop(struct clock_event_device *clk) static int __cpuinit arch_timer_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) { - struct clock_event_device *evt = this_cpu_ptr(arch_timer_evt); - + /* + * Grab cpu pointer in each case to avoid spurious + * preemptible warnings + */ switch (action & ~CPU_TASKS_FROZEN) { case CPU_STARTING: - arch_timer_setup(evt); + arch_timer_setup(this_cpu_ptr(arch_timer_evt)); break; case CPU_DYING: - arch_timer_stop(evt); + arch_timer_stop(this_cpu_ptr(arch_timer_evt)); break; } -- cgit v1.2.3