From b49c87c2a5059af14b68ee5f596ac0e9c93678bb Mon Sep 17 00:00:00 2001 From: Kevin Hilman Date: Thu, 8 Mar 2007 20:25:13 +0100 Subject: [ARM] 4260/1: clocksource support for Versatile platform Update Versatile to use new clocksource infrastructure for basic timekeeping. Signed-off-by: Kevin Hilman Signed-off-by: Russell King --- arch/arm/mach-versatile/core.c | 75 +++++++++++++++++++----------------------- 1 file changed, 34 insertions(+), 41 deletions(-) (limited to 'arch/arm/mach-versatile') diff --git a/arch/arm/mach-versatile/core.c b/arch/arm/mach-versatile/core.c index bf71507c76f..08a9fe6eead 100644 --- a/arch/arm/mach-versatile/core.c +++ b/arch/arm/mach-versatile/core.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include @@ -828,46 +829,6 @@ void __init versatile_init(void) #define TICKS2USECS(x) ((x) / TICKS_PER_uSEC) #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 */ @@ -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, }; + -- cgit v1.2.3