diff options
Diffstat (limited to 'arch/arm/plat-s3c/time.c')
| -rw-r--r-- | arch/arm/plat-s3c/time.c | 81 |
1 files changed, 53 insertions, 28 deletions
diff --git a/arch/arm/plat-s3c/time.c b/arch/arm/plat-s3c/time.c index c6861a05a291..3b27b29da478 100644 --- a/arch/arm/plat-s3c/time.c +++ b/arch/arm/plat-s3c/time.c @@ -26,6 +26,7 @@ #include <linux/err.h> #include <linux/clk.h> #include <linux/io.h> +#include <linux/platform_device.h> #include <asm/system.h> #include <asm/leds.h> @@ -36,6 +37,7 @@ #include <plat/regs-timer.h> #include <mach/regs-irq.h> #include <asm/mach/time.h> +#include <mach/tick.h> #include <plat/clock.h> #include <plat/cpu.h> @@ -43,6 +45,10 @@ static unsigned long timer_startval; static unsigned long timer_usec_ticks; +#ifndef TICK_MAX +#define TICK_MAX (0xffff) +#endif + #define TIMER_USEC_SHIFT 16 /* we use the shifted arithmetic to work out the ratio of timer ticks @@ -91,12 +97,9 @@ static inline unsigned long timer_ticks_to_usec(unsigned long ticks) * IRQs are disabled before entering here from do_gettimeofday() */ -#define SRCPND_TIMER4 (1<<(IRQ_TIMER4 - IRQ_EINT0)) - static unsigned long s3c2410_gettimeoffset (void) { unsigned long tdone; - unsigned long irqpend; unsigned long tval; /* work out how many ticks have gone since last timer interrupt */ @@ -106,8 +109,7 @@ static unsigned long s3c2410_gettimeoffset (void) /* check to see if there is an interrupt pending */ - irqpend = __raw_readl(S3C2410_SRCPND); - if (irqpend & SRCPND_TIMER4) { + if (s3c24xx_ostimer_pending()) { /* re-read the timer, and try and fix up for the missed * interrupt. Note, the interrupt may go off before the * timer has re-loaded from wrapping. @@ -146,6 +148,10 @@ static struct irqaction s3c2410_timer_irq = { machine_is_anubis() || \ machine_is_osiris()) +static struct clk *tin; +static struct clk *tdiv; +static struct clk *timerclk; + /* * Set up timer interrupt, and return the current time in seconds. * @@ -159,13 +165,7 @@ static void s3c2410_timer_setup (void) unsigned long tcfg1; unsigned long tcfg0; - tcnt = 0xffff; /* default value for tcnt */ - - /* read the current timer configuration bits */ - - tcon = __raw_readl(S3C2410_TCON); - tcfg1 = __raw_readl(S3C2410_TCFG1); - tcfg0 = __raw_readl(S3C2410_TCFG0); + tcnt = TICK_MAX; /* default value for tcnt */ /* configure the system for whichever machine is in use */ @@ -174,11 +174,13 @@ static void s3c2410_timer_setup (void) timer_usec_ticks = timer_mask_usec_ticks(1, 12000000); tcnt = 12000000 / HZ; + tcfg1 = __raw_readl(S3C2410_TCFG1); tcfg1 &= ~S3C2410_TCFG1_MUX4_MASK; tcfg1 |= S3C2410_TCFG1_MUX4_TCLK1; + __raw_writel(tcfg1, S3C2410_TCFG1); } else { unsigned long pclk; - struct clk *clk; + struct clk *tscaler; /* for the h1940 (and others), we use the pclk from the core * to generate the timer values. since values around 50 to @@ -189,29 +191,25 @@ static void s3c2410_timer_setup (void) * (8.45 ticks per usec) */ - /* this is used as default if no other timer can be found */ - - clk = clk_get(NULL, "timers"); - if (IS_ERR(clk)) - panic("failed to get clock for system timer"); - - clk_enable(clk); - - pclk = clk_get_rate(clk); + pclk = clk_get_rate(timerclk); /* configure clock tick */ timer_usec_ticks = timer_mask_usec_ticks(6, pclk); - tcfg1 &= ~S3C2410_TCFG1_MUX4_MASK; - tcfg1 |= S3C2410_TCFG1_MUX4_DIV2; + tscaler = clk_get_parent(tdiv); - tcfg0 &= ~S3C2410_TCFG_PRESCALER1_MASK; - tcfg0 |= ((6 - 1) / 2) << S3C2410_TCFG_PRESCALER1_SHIFT; + clk_set_rate(tscaler, pclk / 3); + clk_set_rate(tdiv, pclk / 6); + clk_set_parent(tin, tdiv); - tcnt = (pclk / 6) / HZ; + tcnt = clk_get_rate(tin) / HZ; } + tcon = __raw_readl(S3C2410_TCON); + tcfg0 = __raw_readl(S3C2410_TCFG0); + tcfg1 = __raw_readl(S3C2410_TCFG1); + /* timers reload after counting zero, so reduce the count by 1 */ tcnt--; @@ -220,7 +218,7 @@ static void s3c2410_timer_setup (void) tcon, tcnt, tcfg0, tcfg1, timer_usec_ticks); /* check to see if timer is within 16bit range... */ - if (tcnt > 0xffff) { + if (tcnt > TICK_MAX) { panic("setup_timer: HZ is too small, cannot configure timer!"); return; } @@ -247,8 +245,35 @@ static void s3c2410_timer_setup (void) __raw_writel(tcon, S3C2410_TCON); } +static void __init s3c2410_timer_resources(void) +{ + struct platform_device tmpdev; + + tmpdev.dev.bus = &platform_bus_type; + tmpdev.id = 4; + + timerclk = clk_get(NULL, "timers"); + if (IS_ERR(timerclk)) + panic("failed to get clock for system timer"); + + clk_enable(timerclk); + + if (!use_tclk1_12()) { + tin = clk_get(&tmpdev.dev, "pwm-tin"); + if (IS_ERR(tin)) + panic("failed to get pwm-tin clock for system timer"); + + tdiv = clk_get(&tmpdev.dev, "pwm-tdiv"); + if (IS_ERR(tdiv)) + panic("failed to get pwm-tdiv clock for system timer"); + } + + clk_enable(tin); +} + static void __init s3c2410_timer_init(void) { + s3c2410_timer_resources(); s3c2410_timer_setup(); setup_irq(IRQ_TIMER4, &s3c2410_timer_irq); } |