Daniel Lezcano
danie****@linar*****
2015年 11月 9日 (月) 19:06:48 JST
The current code retrieves the rate value when the timer is enabled which occurs each time a timer is re-armed. Except if the clock frequency has changed magically I don't see why this should be done each time. Retrieve the clock rate value at init time only. Signed-off-by: Daniel Lezcano <danie****@linar*****> --- drivers/clocksource/h8300_timer8.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) diff --git a/drivers/clocksource/h8300_timer8.c b/drivers/clocksource/h8300_timer8.c index 24d91b1..187c416 100644 --- a/drivers/clocksource/h8300_timer8.c +++ b/drivers/clocksource/h8300_timer8.c @@ -34,7 +34,6 @@ struct timer8_priv { unsigned long flags; unsigned int rate; unsigned int tcora; - struct clk *pclk; }; static unsigned long timer8_get_counter(struct timer8_priv *p) @@ -92,7 +91,6 @@ static void timer8_set_next(struct timer8_priv *p, unsigned long delta) static int timer8_enable(struct timer8_priv *p) { - p->rate = clk_get_rate(p->pclk) / SCALE; ctrl_outw(0xffff, p->mapbase + TCORA); ctrl_outw(0x0000, p->mapbase + _8TCNT); ctrl_outw(0x0c02, p->mapbase + _8TCR); @@ -102,16 +100,15 @@ static int timer8_enable(struct timer8_priv *p) static int timer8_start(struct timer8_priv *p) { - int ret = 0; + int ret; - if (!(p->flags & FLAG_STARTED)) - ret = timer8_enable(p); + if ((p->flags & FLAG_STARTED)) + return 0; - if (ret) - goto out; - p->flags |= FLAG_STARTED; + ret = timer8_enable(p); + if (!ret) + p->flags |= FLAG_STARTED; - out: return ret; } @@ -217,7 +214,12 @@ static void __init h8300_8timer_init(struct device_node *node) } timer8_priv.mapbase = (unsigned long)base; - timer8_priv.pclk = clk; + + rate = clk_get_rate(clk) / SCALE; + if (!rate) { + pr_err("Failed to get rate for the clocksource\n"); + goto unmap_reg; + } ret = request_irq(irq, timer8_interrupt, IRQF_TIMER, timer8_priv.ced.name, &timer8_priv); @@ -225,10 +227,10 @@ static void __init h8300_8timer_init(struct device_node *node) pr_err("failed to request irq %d for clockevent\n", irq); goto unmap_reg; } - rate = clk_get_rate(clk) / SCALE; + clockevents_config_and_register(&timer8_priv.ced, rate, 1, 0x0000ffff); - return; + return; unmap_reg: iounmap(base); free_clk: -- 1.9.1
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