| Message ID | 1430128266-15012-1-git-send-email-sudeep.holla@arm.com (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Delegated to: | Rafael Wysocki |
| Headers | show |
On 27 April 2015 at 15:21, Sudeep Holla <sudeep.holla@arm.com> wrote: > The actual frequency is set through "clk_change_rate" which is void > function. If the underlying hardware fails and returns error, the error > is lost in the clk layer. In order to track such failures, we need to > read back the frequency(just the cached value as clk_recalc called after > clk->ops->set_rate gets the frequency) > > This patch adds check to see if the frequency is set correctly or if > they were any hardware failures and sends the appropriate errors to the > cpufreq core. > > Cc: Viresh Kumar <viresh.kumar@linaro.org> > Reviewed-by: Michael Turquette <mike.turquette@linaro.org> > Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> > --- > drivers/cpufreq/arm_big_little.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/cpufreq/arm_big_little.c b/drivers/cpufreq/arm_big_little.c > index e1a6ba66a7f5..f65e19f340d0 100644 > --- a/drivers/cpufreq/arm_big_little.c > +++ b/drivers/cpufreq/arm_big_little.c > @@ -186,6 +186,15 @@ bL_cpufreq_set_rate(u32 cpu, u32 old_cluster, u32 new_cluster, u32 rate) > mutex_unlock(&cluster_lock[old_cluster]); > } > > + /* > + * FIXME: clk_set_rate has to handle the case where clk_change_rate > + * can fail due to hardware or firmware issues. Until the clk core > + * layer is fixed, we can check here. In most of the cases we will > + * be reading only the cached value anyway. This needs to be removed > + * once clk core is fixed. > + */ > + if (bL_cpufreq_get_rate(cpu) != new_rate) > + return -EIO; > return 0; > } Acked-by: Viresh Kumar <viresh.kumar@linaro.org> -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Monday, April 27, 2015 03:56:18 PM Viresh Kumar wrote: > On 27 April 2015 at 15:21, Sudeep Holla <sudeep.holla@arm.com> wrote: > > The actual frequency is set through "clk_change_rate" which is void > > function. If the underlying hardware fails and returns error, the error > > is lost in the clk layer. In order to track such failures, we need to > > read back the frequency(just the cached value as clk_recalc called after > > clk->ops->set_rate gets the frequency) > > > > This patch adds check to see if the frequency is set correctly or if > > they were any hardware failures and sends the appropriate errors to the > > cpufreq core. > > > > Cc: Viresh Kumar <viresh.kumar@linaro.org> > > Reviewed-by: Michael Turquette <mike.turquette@linaro.org> > > Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> > > --- > > drivers/cpufreq/arm_big_little.c | 9 +++++++++ > > 1 file changed, 9 insertions(+) > > > > diff --git a/drivers/cpufreq/arm_big_little.c b/drivers/cpufreq/arm_big_little.c > > index e1a6ba66a7f5..f65e19f340d0 100644 > > --- a/drivers/cpufreq/arm_big_little.c > > +++ b/drivers/cpufreq/arm_big_little.c > > @@ -186,6 +186,15 @@ bL_cpufreq_set_rate(u32 cpu, u32 old_cluster, u32 new_cluster, u32 rate) > > mutex_unlock(&cluster_lock[old_cluster]); > > } > > > > + /* > > + * FIXME: clk_set_rate has to handle the case where clk_change_rate > > + * can fail due to hardware or firmware issues. Until the clk core > > + * layer is fixed, we can check here. In most of the cases we will > > + * be reading only the cached value anyway. This needs to be removed > > + * once clk core is fixed. > > + */ > > + if (bL_cpufreq_get_rate(cpu) != new_rate) > > + return -EIO; > > return 0; > > } > > Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Both queued up for 4.2, thanks!
diff --git a/drivers/cpufreq/arm_big_little.c b/drivers/cpufreq/arm_big_little.c index e1a6ba66a7f5..f65e19f340d0 100644 --- a/drivers/cpufreq/arm_big_little.c +++ b/drivers/cpufreq/arm_big_little.c @@ -186,6 +186,15 @@ bL_cpufreq_set_rate(u32 cpu, u32 old_cluster, u32 new_cluster, u32 rate) mutex_unlock(&cluster_lock[old_cluster]); } + /* + * FIXME: clk_set_rate has to handle the case where clk_change_rate + * can fail due to hardware or firmware issues. Until the clk core + * layer is fixed, we can check here. In most of the cases we will + * be reading only the cached value anyway. This needs to be removed + * once clk core is fixed. + */ + if (bL_cpufreq_get_rate(cpu) != new_rate) + return -EIO; return 0; }