diff options
| -rw-r--r-- | arch/arm/Kconfig | 1 | ||||
| -rw-r--r-- | arch/arm/mach-versatile/core.c | 75 |
2 files changed, 35 insertions, 41 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 2aadd0e1e586..cddd054676c0 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -166,6 +166,7 @@ config ARCH_VERSATILE select ARM_AMBA select ARM_VIC select ICST307 + select GENERIC_TIME help This enables support for ARM Ltd Versatile board. diff --git a/arch/arm/mach-versatile/core.c b/arch/arm/mach-versatile/core.c index bf71507c76fd..08a9fe6eeadb 100644 --- a/arch/arm/mach-versatile/core.c +++ b/arch/arm/mach-versatile/core.c @@ -26,6 +26,7 @@ #include <linux/interrupt.h> #include <linux/amba/bus.h> #include <linux/amba/clcd.h> +#include <linux/clocksource.h> #include <asm/cnt32_to_63.h> #include <asm/system.h> @@ -829,46 +830,6 @@ void __init versatile_init(void) #endif /* - * Returns number of ms since last clock interrupt. Note that interrupts - * will have been disabled by do_gettimeoffset() - */ -static unsigned long versatile_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(VA_IC_BASE + VIC_RAW_STATUS); - 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 versatile_timer_interrupt(int irq, void *dev_id) @@ -891,6 +852,36 @@ static struct irqaction versatile_timer_irq = { .handler = versatile_timer_interrupt, }; +static cycle_t versatile_get_cycles(void) +{ + return ~readl(TIMER3_VA_BASE + TIMER_VALUE); +} + +static struct clocksource clocksource_versatile = { + .name = "timer3", + .rating = 200, + .read = versatile_get_cycles, + .mask = CLOCKSOURCE_MASK(32), + .shift = 20, + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +static int __init versatile_clocksource_init(void) +{ + /* setup timer3 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_versatile.mult = + clocksource_khz2mult(1000, clocksource_versatile.shift); + clocksource_register(&clocksource_versatile); + + return 0; +} + /* * Set up timer interrupt, and return the current time in seconds. */ @@ -927,9 +918,11 @@ static void __init versatile_timer_init(void) * Make irqs happen for the system timer */ setup_irq(IRQ_TIMERINT0_1, &versatile_timer_irq); + + versatile_clocksource_init(); } struct sys_timer versatile_timer = { .init = versatile_timer_init, - .offset = versatile_gettimeoffset, }; + |