diff options
Diffstat (limited to 'arch/arm/mach-at91/at91rm9200_time.c')
| -rw-r--r-- | arch/arm/mach-at91/at91rm9200_time.c | 117 |
1 files changed, 90 insertions, 27 deletions
diff --git a/arch/arm/mach-at91/at91rm9200_time.c b/arch/arm/mach-at91/at91rm9200_time.c index a028cdf8f97..7fd13aef982 100644 --- a/arch/arm/mach-at91/at91rm9200_time.c +++ b/arch/arm/mach-at91/at91rm9200_time.c @@ -23,10 +23,15 @@ #include <linux/interrupt.h> #include <linux/irq.h> #include <linux/clockchips.h> +#include <linux/export.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> #include <asm/mach/time.h> #include <mach/at91_st.h> +#include <mach/hardware.h> static unsigned long last_crtr; static u32 irqmask; @@ -43,9 +48,9 @@ static inline unsigned long read_CRTR(void) { unsigned long x1, x2; - x1 = at91_sys_read(AT91_ST_CRTR); + x1 = at91_st_read(AT91_ST_CRTR); do { - x2 = at91_sys_read(AT91_ST_CRTR); + x2 = at91_st_read(AT91_ST_CRTR); if (x1 == x2) break; x1 = x2; @@ -58,7 +63,7 @@ static inline unsigned long read_CRTR(void) */ static irqreturn_t at91rm9200_timer_interrupt(int irq, void *dev_id) { - u32 sr = at91_sys_read(AT91_ST_SR) & irqmask; + u32 sr = at91_st_read(AT91_ST_SR) & irqmask; /* * irqs should be disabled here, but as the irq is shared they are only @@ -89,8 +94,9 @@ static irqreturn_t at91rm9200_timer_interrupt(int irq, void *dev_id) static struct irqaction at91rm9200_timer_irq = { .name = "at91_tick", - .flags = IRQF_SHARED | IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, - .handler = at91rm9200_timer_interrupt + .flags = IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL, + .handler = at91rm9200_timer_interrupt, + .irq = NR_IRQS_LEGACY + AT91_ID_SYS, }; static cycle_t read_clk32k(struct clocksource *cs) @@ -110,22 +116,22 @@ static void clkevt32k_mode(enum clock_event_mode mode, struct clock_event_device *dev) { /* Disable and flush pending timer interrupts */ - at91_sys_write(AT91_ST_IDR, AT91_ST_PITS | AT91_ST_ALMS); - (void) at91_sys_read(AT91_ST_SR); + at91_st_write(AT91_ST_IDR, AT91_ST_PITS | AT91_ST_ALMS); + at91_st_read(AT91_ST_SR); last_crtr = read_CRTR(); switch (mode) { case CLOCK_EVT_MODE_PERIODIC: /* PIT for periodic irqs; fixed rate of 1/HZ */ irqmask = AT91_ST_PITS; - at91_sys_write(AT91_ST_PIMR, RM9200_TIMER_LATCH); + at91_st_write(AT91_ST_PIMR, RM9200_TIMER_LATCH); break; case CLOCK_EVT_MODE_ONESHOT: /* ALM for oneshot irqs, set by next_event() * before 32 seconds have passed */ irqmask = AT91_ST_ALMS; - at91_sys_write(AT91_ST_RTAR, last_crtr); + at91_st_write(AT91_ST_RTAR, last_crtr); break; case CLOCK_EVT_MODE_SHUTDOWN: case CLOCK_EVT_MODE_UNUSED: @@ -133,7 +139,7 @@ clkevt32k_mode(enum clock_event_mode mode, struct clock_event_device *dev) irqmask = 0; break; } - at91_sys_write(AT91_ST_IER, irqmask); + at91_st_write(AT91_ST_IER, irqmask); } static int @@ -156,12 +162,12 @@ clkevt32k_next_event(unsigned long delta, struct clock_event_device *dev) alm = read_CRTR(); /* Cancel any pending alarm; flush any pending IRQ */ - at91_sys_write(AT91_ST_RTAR, alm); - (void) at91_sys_read(AT91_ST_SR); + at91_st_write(AT91_ST_RTAR, alm); + at91_st_read(AT91_ST_SR); /* Schedule alarm by writing RTAR. */ alm += delta; - at91_sys_write(AT91_ST_RTAR, alm); + at91_st_write(AT91_ST_RTAR, alm); return status; } @@ -169,43 +175,100 @@ clkevt32k_next_event(unsigned long delta, struct clock_event_device *dev) static struct clock_event_device clkevt = { .name = "at91_tick", .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, - .shift = 32, .rating = 150, .set_next_event = clkevt32k_next_event, .set_mode = clkevt32k_mode, }; +void __iomem *at91_st_base; +EXPORT_SYMBOL_GPL(at91_st_base); + +#ifdef CONFIG_OF +static struct of_device_id at91rm9200_st_timer_ids[] = { + { .compatible = "atmel,at91rm9200-st" }, + { /* sentinel */ } +}; + +static int __init of_at91rm9200_st_init(void) +{ + struct device_node *np; + int ret; + + np = of_find_matching_node(NULL, at91rm9200_st_timer_ids); + if (!np) + goto err; + + at91_st_base = of_iomap(np, 0); + if (!at91_st_base) + goto node_err; + + /* Get the interrupts property */ + ret = irq_of_parse_and_map(np, 0); + if (!ret) + goto ioremap_err; + at91rm9200_timer_irq.irq = ret; + + of_node_put(np); + + return 0; + +ioremap_err: + iounmap(at91_st_base); +node_err: + of_node_put(np); +err: + return -EINVAL; +} +#else +static int __init of_at91rm9200_st_init(void) +{ + return -EINVAL; +} +#endif + +void __init at91rm9200_ioremap_st(u32 addr) +{ +#ifdef CONFIG_OF + struct device_node *np; + + np = of_find_matching_node(NULL, at91rm9200_st_timer_ids); + if (np) { + of_node_put(np); + return; + } +#endif + at91_st_base = ioremap(addr, 256); + if (!at91_st_base) + panic("Impossible to ioremap ST\n"); +} + /* * ST (system timer) module supports both clockevents and clocksource. */ void __init at91rm9200_timer_init(void) { + /* For device tree enabled device: initialize here */ + of_at91rm9200_st_init(); + /* Disable all timer interrupts, and clear any pending ones */ - at91_sys_write(AT91_ST_IDR, + at91_st_write(AT91_ST_IDR, AT91_ST_PITS | AT91_ST_WDOVF | AT91_ST_RTTINC | AT91_ST_ALMS); - (void) at91_sys_read(AT91_ST_SR); + at91_st_read(AT91_ST_SR); /* Make IRQs happen for the system timer */ - setup_irq(AT91_ID_SYS, &at91rm9200_timer_irq); + setup_irq(at91rm9200_timer_irq.irq, &at91rm9200_timer_irq); /* The 32KiHz "Slow Clock" (tick every 30517.58 nanoseconds) is used * directly for the clocksource and all clockevents, after adjusting * its prescaler from the 1 Hz default. */ - at91_sys_write(AT91_ST_RTMR, 1); + at91_st_write(AT91_ST_RTMR, 1); /* Setup timer clockevent, with minimum of two ticks (important!!) */ - clkevt.mult = div_sc(AT91_SLOW_CLOCK, NSEC_PER_SEC, clkevt.shift); - clkevt.max_delta_ns = clockevent_delta2ns(AT91_ST_ALMV, &clkevt); - clkevt.min_delta_ns = clockevent_delta2ns(2, &clkevt) + 1; clkevt.cpumask = cpumask_of(0); - clockevents_register_device(&clkevt); + clockevents_config_and_register(&clkevt, AT91_SLOW_CLOCK, + 2, AT91_ST_ALMV); /* register clocksource */ clocksource_register_hz(&clk32k, AT91_SLOW_CLOCK); } - -struct sys_timer at91rm9200_timer = { - .init = at91rm9200_timer_init, -}; - |