diff options
| -rw-r--r-- | arch/arm/Kconfig | 1 | ||||
| -rw-r--r-- | arch/arm/mach-realview/core.c | 73 |
2 files changed, 32 insertions, 42 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 4b1a8e3d292..a2b7e4a52f7 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -168,6 +168,7 @@ config ARCH_REALVIEW bool "ARM Ltd. RealView family" select ARM_AMBA select ICST307 + select GENERIC_TIME help This enables support for ARM Ltd RealView boards. diff --git a/arch/arm/mach-realview/core.c b/arch/arm/mach-realview/core.c index 61d70218f1e..f805840f6f4 100644 --- a/arch/arm/mach-realview/core.c +++ b/arch/arm/mach-realview/core.c @@ -25,6 +25,7 @@ #include <linux/interrupt.h> #include <linux/amba/bus.h> #include <linux/amba/clcd.h> +#include <linux/clocksource.h> #include <asm/system.h> #include <asm/hardware.h> @@ -485,47 +486,6 @@ void realview_leds_event(led_event_t ledevt) #endif /* - * Returns number of ms since last clock interrupt. Note that interrupts - * will have been disabled by do_gettimeoffset() - */ -static unsigned long realview_gettimeoffset(void) -{ - unsigned long ticks1, ticks2, status; - - /* - * Get the current number of ticks. Note that there is a race - * condition between us reading the timer and checking for - * an interrupt. We get around this by ensuring that the - * counter has not reloaded between our two reads. - */ - ticks2 = readl(TIMER0_VA_BASE + TIMER_VALUE) & 0xffff; - do { - ticks1 = ticks2; - status = __raw_readl(__io_address(REALVIEW_GIC_DIST_BASE + GIC_DIST_PENDING_SET) - + ((IRQ_TIMERINT0_1 >> 5) << 2)); - ticks2 = readl(TIMER0_VA_BASE + TIMER_VALUE) & 0xffff; - } while (ticks2 > ticks1); - - /* - * Number of ticks since last interrupt. - */ - ticks1 = TIMER_RELOAD - ticks2; - - /* - * Interrupt pending? If so, we've reloaded once already. - * - * FIXME: Need to check this is effectively timer 0 that expires - */ - if (status & IRQMASK_TIMERINT0_1) - ticks1 += TIMER_RELOAD; - - /* - * Convert the ticks to usecs - */ - return TICKS2USECS(ticks1); -} - -/* * IRQ handler for the timer */ static irqreturn_t realview_timer_interrupt(int irq, void *dev_id) @@ -549,6 +509,34 @@ static struct irqaction realview_timer_irq = { .handler = realview_timer_interrupt, }; +static cycle_t realview_get_cycles(void) +{ + return ~readl(TIMER3_VA_BASE + TIMER_VALUE); +} + +static struct clocksource clocksource_realview = { + .name = "timer3", + .rating = 200, + .read = realview_get_cycles, + .mask = CLOCKSOURCE_MASK(32), + .shift = 20, + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +static void __init realview_clocksource_init(void) +{ + /* setup timer 0 as free-running clocksource */ + writel(0, TIMER3_VA_BASE + TIMER_CTRL); + writel(0xffffffff, TIMER3_VA_BASE + TIMER_LOAD); + writel(0xffffffff, TIMER3_VA_BASE + TIMER_VALUE); + writel(TIMER_CTRL_32BIT | TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC, + TIMER3_VA_BASE + TIMER_CTRL); + + clocksource_realview.mult = + clocksource_khz2mult(1000, clocksource_realview.shift); + clocksource_register(&clocksource_realview); +} + /* * Set up timer interrupt, and return the current time in seconds. */ @@ -585,9 +573,10 @@ static void __init realview_timer_init(void) * Make irqs happen for the system timer */ setup_irq(IRQ_TIMERINT0_1, &realview_timer_irq); + + realview_clocksource_init(); } struct sys_timer realview_timer = { .init = realview_timer_init, - .offset = realview_gettimeoffset, }; |