[PATCH] cpufreq: Align all CPUs to the same frequency if using shared clock

From: lizhuangzhi
Date: Mon Jan 20 2014 - 22:11:53 EST


Some SMP systems want to make all the possible CPUs share the clock,
if the CPUs init frequencies aren't the same, we need to align all the
CPUs to the same frequency while CPUs registing to avoid mismatched
CPU's P-states.

Signed-off-by: lizhuangzhi <zhuangzhi.li@xxxxxxxxx>
---
drivers/cpufreq/cpufreq.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 8d19f7c..d00abb5 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -991,6 +991,8 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif,
* CPU because it is in the same boat. */
policy = cpufreq_cpu_get(cpu);
if (unlikely(policy)) {
+ /* according present policy to align all the cpus frequencies */
+ cpufreq_driver->target(policy, policy->cur, CPUFREQ_RELATION_H);
cpufreq_cpu_put(policy);
return 0;
}
--
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/