ARM: fix footbridge clockevent device
authorRussell King <rmk+kernel@arm.linux.org.uk>
Sun, 29 Dec 2013 12:39:50 +0000 (12:39 +0000)
committerRussell King <rmk+kernel@arm.linux.org.uk>
Sun, 29 Dec 2013 12:41:20 +0000 (12:41 +0000)
The clockevents code was being told that the footbridge clock event
device ticks at 16x the rate which it actually does.  This leads to
timekeeping problems since it allows the clocksource to wrap before
the kernel notices.  Fix this by using the correct clock.

Fixes: 4e8d76373c9fd ("ARM: footbridge: convert to clockevents/clocksource")
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: <stable@vger.kernel.org>
arch/arm/mach-footbridge/dc21285-timer.c

index 9ee78f7b4990751386cf7f29337ec075297349dd..782f6c71fa0a6c761269cfc4b74fc6cdd0839e75 100644 (file)
@@ -96,11 +96,12 @@ static struct irqaction footbridge_timer_irq = {
 void __init footbridge_timer_init(void)
 {
        struct clock_event_device *ce = &ckevt_dc21285;
+       unsigned rate = DIV_ROUND_CLOSEST(mem_fclk_21285, 16);
 
-       clocksource_register_hz(&cksrc_dc21285, (mem_fclk_21285 + 8) / 16);
+       clocksource_register_hz(&cksrc_dc21285, rate);
 
        setup_irq(ce->irq, &footbridge_timer_irq);
 
        ce->cpumask = cpumask_of(smp_processor_id());
-       clockevents_config_and_register(ce, mem_fclk_21285, 0x4, 0xffffff);
+       clockevents_config_and_register(ce, rate, 0x4, 0xffffff);
 }