From 0075242b3a2f78901172aaadf73beed762a1f02f Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Thu, 19 Jan 2012 13:53:50 +0000 Subject: [PATCH] ARM: architected timers: add DT support Add runtime DT support and documentation for the Cortex A7/A15 architected timers. Signed-off-by: Will Deacon Signed-off-by: Marc Zyngier --- .../devicetree/bindings/arm/arch_timer.txt | 27 ++++++++++ arch/arm/include/asm/arch_timer.h | 6 +++ arch/arm/kernel/arch_timer.c | 53 ++++++++++++++++--- 3 files changed, 79 insertions(+), 7 deletions(-) create mode 100644 Documentation/devicetree/bindings/arm/arch_timer.txt diff --git a/Documentation/devicetree/bindings/arm/arch_timer.txt b/Documentation/devicetree/bindings/arm/arch_timer.txt new file mode 100644 index 000000000000..52478c83d0cc --- /dev/null +++ b/Documentation/devicetree/bindings/arm/arch_timer.txt @@ -0,0 +1,27 @@ +* ARM architected timer + +ARM Cortex-A7 and Cortex-A15 have a per-core architected timer, which +provides per-cpu timers. + +The timer is attached to a GIC to deliver its per-processor interrupts. + +** Timer node properties: + +- compatible : Should at least contain "arm,armv7-timer". + +- interrupts : Interrupt list for secure, non-secure, virtual and + hypervisor timers, in that order. + +- clock-frequency : The frequency of the main counter, in Hz. Optional. + +Example: + + timer { + compatible = "arm,cortex-a15-timer", + "arm,armv7-timer"; + interrupts = <1 13 0xf08>, + <1 14 0xf08>, + <1 11 0xf08>, + <1 10 0xf08>; + clock-frequency = <100000000>; + }; diff --git a/arch/arm/include/asm/arch_timer.h b/arch/arm/include/asm/arch_timer.h index dc008c696b5a..935897f120b6 100644 --- a/arch/arm/include/asm/arch_timer.h +++ b/arch/arm/include/asm/arch_timer.h @@ -10,12 +10,18 @@ struct arch_timer { #ifdef CONFIG_ARM_ARCH_TIMER int arch_timer_register(struct arch_timer *); int arch_timer_sched_clock_init(void); +int arch_timer_of_register(void); #else static inline int arch_timer_register(struct arch_timer *at) { return -ENXIO; } +static inline int arch_timer_of_register(void) +{ + return -ENXIO; +} + static inline int arch_timer_sched_clock_init(void) { return -ENXIO; diff --git a/arch/arm/kernel/arch_timer.c b/arch/arm/kernel/arch_timer.c index dd907048f571..1a34eeebc26e 100644 --- a/arch/arm/kernel/arch_timer.c +++ b/arch/arm/kernel/arch_timer.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include @@ -245,13 +246,10 @@ static struct local_timer_ops arch_timer_ops __cpuinitdata = { .stop = arch_timer_stop, }; -int __init arch_timer_register(struct arch_timer *at) +static int __init arch_timer_common_register(void) { int err; - if (at->res[0].start <= 0 || !(at->res[0].flags & IORESOURCE_IRQ)) - return -EINVAL; - err = arch_timer_available(); if (err) return err; @@ -262,7 +260,6 @@ int __init arch_timer_register(struct arch_timer *at) clocksource_register_hz(&clocksource_counter, arch_timer_rate); - arch_timer_ppi = at->res[0].start; err = request_percpu_irq(arch_timer_ppi, arch_timer_handler, "arch_timer", arch_timer_evt); if (err) { @@ -271,8 +268,7 @@ int __init arch_timer_register(struct arch_timer *at) goto out_free; } - if (at->res[1].start > 0 || (at->res[1].flags & IORESOURCE_IRQ)) { - arch_timer_ppi2 = at->res[1].start; + if (arch_timer_ppi2) { err = request_percpu_irq(arch_timer_ppi2, arch_timer_handler, "arch_timer", arch_timer_evt); if (err) { @@ -300,6 +296,49 @@ out_free: return err; } +int __init arch_timer_register(struct arch_timer *at) +{ + if (at->res[0].start <= 0 || !(at->res[0].flags & IORESOURCE_IRQ)) + return -EINVAL; + + arch_timer_ppi = at->res[0].start; + + if (at->res[1].start > 0 || (at->res[1].flags & IORESOURCE_IRQ)) + arch_timer_ppi2 = at->res[1].start; + + return arch_timer_common_register(); +} + +#ifdef CONFIG_OF +static const struct of_device_id arch_timer_of_match[] __initconst = { + { .compatible = "arm,armv7-timer", }, + {}, +}; + +int __init arch_timer_of_register(void) +{ + struct device_node *np; + u32 freq; + + np = of_find_matching_node(NULL, arch_timer_of_match); + if (!np) { + pr_err("arch_timer: can't find DT node\n"); + return -ENODEV; + } + + /* Try to determine the frequency from the device tree or CNTFRQ */ + if (!of_property_read_u32(np, "clock-frequency", &freq)) + arch_timer_rate = freq; + + arch_timer_ppi = irq_of_parse_and_map(np, 0); + arch_timer_ppi2 = irq_of_parse_and_map(np, 1); + pr_info("arch_timer: found %s irqs %d %d\n", + np->name, arch_timer_ppi, arch_timer_ppi2); + + return arch_timer_common_register(); +} +#endif + int __init arch_timer_sched_clock_init(void) { int err; -- 2.20.1