On 27 April 2015 at 15:21, Sudeep Holla <[email protected]> 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 <[email protected]> > Reviewed-by: Michael Turquette <[email protected]> > Signed-off-by: Sudeep Holla <[email protected]> > --- > 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 <[email protected]> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
