diff options
Diffstat (limited to 'arch/arc/kernel/time.c')
| -rw-r--r-- | arch/arc/kernel/time.c | 59 |
1 files changed, 43 insertions, 16 deletions
diff --git a/arch/arc/kernel/time.c b/arch/arc/kernel/time.c index 848353a27ac8..01ec30d83590 100644 --- a/arch/arc/kernel/time.c +++ b/arch/arc/kernel/time.c @@ -30,19 +30,15 @@ */ #include <linux/interrupt.h> -#include <linux/module.h> -#include <linux/kernel.h> -#include <linux/time.h> -#include <linux/init.h> #include <linux/clk.h> #include <linux/clk-provider.h> #include <linux/clocksource.h> #include <linux/clockchips.h> #include <linux/cpu.h> +#include <linux/of.h> +#include <linux/of_irq.h> #include <asm/irq.h> #include <asm/arcregs.h> -#include <asm/clk.h> -#include <asm/mach_desc.h> #include <asm/mcip.h> @@ -59,6 +55,30 @@ #define ARC_TIMER_MAX 0xFFFFFFFF +static unsigned long arc_timer_freq; + +static int noinline arc_get_timer_clk(struct device_node *node) +{ + struct clk *clk; + int ret; + + clk = of_clk_get(node, 0); + if (IS_ERR(clk)) { + pr_err("timer missing clk"); + return PTR_ERR(clk); + } + + ret = clk_prepare_enable(clk); + if (ret) { + pr_err("Couldn't enable parent clk\n"); + return ret; + } + + arc_timer_freq = clk_get_rate(clk); + + return 0; +} + /********** Clock Source Device *********/ #ifdef CONFIG_ARC_HAS_GFRC @@ -182,7 +202,7 @@ static struct clocksource arc_counter = { /********** Clock Event Device *********/ -static int arc_timer_irq = TIMER0_IRQ; +static int arc_timer_irq; /* * Arm the timer to interrupt after @cycles @@ -210,7 +230,7 @@ static int arc_clkevent_set_periodic(struct clock_event_device *dev) * At X Hz, 1 sec = 1000ms -> X cycles; * 10ms -> X / 100 cycles */ - arc_timer_event_setup(arc_get_core_freq() / HZ); + arc_timer_event_setup(arc_timer_freq / HZ); return 0; } @@ -253,7 +273,7 @@ static int arc_timer_cpu_notify(struct notifier_block *self, switch (action & ~CPU_TASKS_FROZEN) { case CPU_STARTING: - clockevents_config_and_register(evt, arc_get_core_freq(), + clockevents_config_and_register(evt, arc_timer_freq, 0, ULONG_MAX); enable_percpu_irq(arc_timer_irq, 0); break; @@ -272,25 +292,35 @@ static struct notifier_block arc_timer_cpu_nb = { /* * clockevent setup for boot CPU */ -static void __init arc_clockevent_setup(void) +static void __init arc_clockevent_setup(struct device_node *node) { struct clock_event_device *evt = this_cpu_ptr(&arc_clockevent_device); int ret; register_cpu_notifier(&arc_timer_cpu_nb); + arc_timer_irq = irq_of_parse_and_map(node, 0); + if (arc_timer_irq <= 0) + panic("clockevent: missing irq"); + + ret = arc_get_timer_clk(node); + if (ret) + panic("clockevent: missing clk"); + + evt->irq = arc_timer_irq; evt->cpumask = cpumask_of(smp_processor_id()); - clockevents_config_and_register(evt, arc_get_core_freq(), + clockevents_config_and_register(evt, arc_timer_freq, 0, ARC_TIMER_MAX); /* Needs apriori irq_set_percpu_devid() done in intc map function */ ret = request_percpu_irq(arc_timer_irq, timer_irq_handler, "Timer0 (per-cpu-tick)", evt); if (ret) - pr_err("Unable to register interrupt\n"); + panic("clockevent: unable to request irq\n"); enable_percpu_irq(arc_timer_irq, 0); } +CLOCKSOURCE_OF_DECLARE(arc_clkevt, "snps,arc-timer", arc_clockevent_setup); /* * Called from start_kernel() - boot CPU only @@ -299,7 +329,6 @@ static void __init arc_clockevent_setup(void) * -Also sets up any global state needed for timer subsystem: * - for "counting" timer, registers a clocksource, usable across CPUs * (provided that underlying counter h/w is synchronized across cores) - * - for "event" timer, sets up TIMER0 IRQ (as that is platform agnostic) */ void __init time_init(void) { @@ -315,7 +344,5 @@ void __init time_init(void) * CLK upto 4.29 GHz can be safely represented in 32 bits * because Max 32 bit number is 4,294,967,295 */ - clocksource_register_hz(&arc_counter, arc_get_core_freq()); - - arc_clockevent_setup(); + clocksource_register_hz(&arc_counter, arc_timer_freq); } |