diff options
| author | Uwe Kleine-König <u.kleine-koenig@pengutronix.de> | 2013-11-05 09:03:19 (GMT) |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2013-11-26 20:00:21 (GMT) |
| commit | 6a79799d5654bb7800614e8b7a009252be7ff90e (patch) | |
| tree | df74f5979cc6de74c6bf2d441505a7e6a23845e7 | |
| parent | 8ddd0f6fa6b542270517affb7d6657061c615ba9 (diff) | |
| download | linux-6a79799d5654bb7800614e8b7a009252be7ff90e.tar.xz | |
ARM: u300: fix timekeeping when periodic mode is used
To determine the value to write to the hardware's timer counter register
the symbol CLOCK_TICK_RATE is used. This value is a dummy value on u300
though. So instead use the clock rate that is used for oneshot mode.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
| -rw-r--r-- | arch/arm/mach-u300/timer.c | 38 |
1 files changed, 24 insertions, 14 deletions
diff --git a/arch/arm/mach-u300/timer.c b/arch/arm/mach-u300/timer.c index 9a5f9fb..5226162 100644 --- a/arch/arm/mach-u300/timer.c +++ b/arch/arm/mach-u300/timer.c @@ -184,11 +184,13 @@ #define U300_TIMER_APP_CRC (0x100) #define U300_TIMER_APP_CRC_CLOCK_REQUEST_ENABLE (0x00000001) -#define TICKS_PER_JIFFY ((CLOCK_TICK_RATE + (HZ/2)) / HZ) -#define US_PER_TICK ((1000000 + (HZ/2)) / HZ) - static void __iomem *u300_timer_base; +struct u300_clockevent_data { + struct clock_event_device cevd; + unsigned ticks_per_jiffy; +}; + /* * The u300_set_mode() function is always called first, if we * have oneshot timer active, the oneshot scheduling function @@ -197,6 +199,9 @@ static void __iomem *u300_timer_base; static void u300_set_mode(enum clock_event_mode mode, struct clock_event_device *evt) { + struct u300_clockevent_data *cevdata = + container_of(evt, struct u300_clockevent_data, cevd); + switch (mode) { case CLOCK_EVT_MODE_PERIODIC: /* Disable interrupts on GPT1 */ @@ -209,7 +214,7 @@ static void u300_set_mode(enum clock_event_mode mode, * Set the periodic mode to a certain number of ticks per * jiffy. */ - writel(TICKS_PER_JIFFY, + writel(cevdata->ticks_per_jiffy, u300_timer_base + U300_TIMER_APP_GPT1TC); /* * Set continuous mode, so the timer keeps triggering @@ -305,20 +310,23 @@ static int u300_set_next_event(unsigned long cycles, return 0; } - -/* Use general purpose timer 1 as clock event */ -static struct clock_event_device clockevent_u300_1mhz = { - .name = "GPT1", - .rating = 300, /* Reasonably fast and accurate clock event */ - .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, - .set_next_event = u300_set_next_event, - .set_mode = u300_set_mode, +static struct u300_clockevent_data u300_clockevent_data = { + /* Use general purpose timer 1 as clock event */ + .cevd = { + .name = "GPT1", + /* Reasonably fast and accurate clock event */ + .rating = 300, + .features = CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_ONESHOT, + .set_next_event = u300_set_next_event, + .set_mode = u300_set_mode, + }, }; /* Clock event timer interrupt handler */ static irqreturn_t u300_timer_interrupt(int irq, void *dev_id) { - struct clock_event_device *evt = &clockevent_u300_1mhz; + struct clock_event_device *evt = &u300_clockevent_data.cevd; /* ACK/Clear timer IRQ for the APP GPT1 Timer */ writel(U300_TIMER_APP_GPT1IA_IRQ_ACK, @@ -379,6 +387,8 @@ static void __init u300_timer_init_of(struct device_node *np) clk_prepare_enable(clk); rate = clk_get_rate(clk); + u300_clockevent_data.ticks_per_jiffy = DIV_ROUND_CLOSEST(rate, HZ); + setup_sched_clock(u300_read_sched_clock, 32, rate); u300_delay_timer.read_current_timer = &u300_read_current_timer; @@ -428,7 +438,7 @@ static void __init u300_timer_init_of(struct device_node *np) pr_err("timer: failed to initialize U300 clock source\n"); /* Configure and register the clockevent */ - clockevents_config_and_register(&clockevent_u300_1mhz, rate, + clockevents_config_and_register(&u300_clockevent_data.cevd, rate, 1, 0xffffffff); /* |