According to the data provided by HW Team, at least 12 internal platform clock cycles are required to stabilize a DFS clock switch on FSL e500mc Socs. This patch replaces the CPUFREQ_ETERNAL with appropriate HW clock transition latency to make DFS governors work normally on Freescale e500mc boards. Signed-off-by: Zhuoyu Zhang <Zhuoyu.Zhang@xxxxxxxxxxxxx> --- drivers/cpufreq/ppc-corenet-cpufreq.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/cpufreq/ppc-corenet-cpufreq.c b/drivers/cpufreq/ppc-corenet-cpufreq.c index 051000f..5977f57 100644 --- a/drivers/cpufreq/ppc-corenet-cpufreq.c +++ b/drivers/cpufreq/ppc-corenet-cpufreq.c @@ -21,6 +21,7 @@ #include <linux/of.h> #include <linux/slab.h> #include <linux/smp.h> +#include <sysdev/fsl_soc.h> /** * struct cpu_data - per CPU data struct @@ -205,7 +206,8 @@ static int corenet_cpufreq_cpu_init(struct cpufreq_policy *policy) for_each_cpu(i, per_cpu(cpu_mask, cpu)) per_cpu(cpu_data, i) = data; - policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL; + policy->cpuinfo.transition_latency = + (12 * NSEC_PER_SEC) / fsl_get_sys_freq(); of_node_put(np); return 0; -- 1.8.4 -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
