On 11/25/2013 02:55 PM, Doug Anderson wrote:
On modern SoCs the watchdog timer is parented on a clock that doesn't change every time we have a cpufreq change. That means we don't need to constantly adjust the watchdog timer, so avoid registering for and dealing with cpufreq transitions unless we've actually got CPU_FREQ_S3C24XX defined. Note that this is more than just an optimization. The s3c2410 watchdog driver actually pats the watchdog on every CPU frequency change. On modern systems these happen many times per second (even in a system where "nothing" is happening). That effectively makes any userspace watchdog program useless (the watchdog is constantly patted by the kernel). If we need CPU_FREQ_S3C24XX defined on a multiplatform kernel we'll need to make sure that kernel supports common clock and change this to user common clock framework. Signed-off-by: Doug Anderson <dianders@xxxxxxxxxxxx> --- drivers/watchdog/s3c2410_wdt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c index 7d8fd04..4980f84 100644 --- a/drivers/watchdog/s3c2410_wdt.c +++ b/drivers/watchdog/s3c2410_wdt.c @@ -264,7 +264,7 @@ static irqreturn_t s3c2410wdt_irq(int irqno, void *param) return IRQ_HANDLED; } -#ifdef CONFIG_CPU_FREQ +#ifdef CONFIG_CPU_FREQ_S3C24XX
Where is the CPU_FREQ_S3C24XX configuration option defined ? I don't see it in the current upstream kernel, so it appears that this depends on some out-of-tree changes. Thanks, Guenter -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
