lkml.org 
[lkml]   [2020]   [Aug]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] opp: Fix dev_pm_opp_set_rate() to not return early
On 2020-08-10 12:36, Rajendra Nayak wrote:
> dev_pm_opp_set_rate() can now be called with freq = 0 inorder
> to either drop performance or bandwidth votes or to disable
> regulators on platforms which support them.
> In such cases, a subsequent call to dev_pm_opp_set_rate() with
> the same frequency ends up returning early because 'old_freq == freq'
> Instead make it fall through and put back the dropped performance
> and bandwidth votes and/or enable back the regulators.
>
> Fixes: cd7ea582 ("opp: Make dev_pm_opp_set_rate() handle freq = 0 to
> drop performance votes")
> Reported-by: Sajida Bhanu <sbhanu@codeaurora.org>
> Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>

Reviewed-by: Sibi Sankar <sibis@codeaurora.org>

> ---
> drivers/opp/core.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/opp/core.c b/drivers/opp/core.c
> index 0c8c74a..a994f30 100644
> --- a/drivers/opp/core.c
> +++ b/drivers/opp/core.c
> @@ -901,6 +901,9 @@ int dev_pm_opp_set_rate(struct device *dev,
> unsigned long target_freq)
>
> /* Return early if nothing to do */
> if (old_freq == freq) {
> + if (opp_table->required_opp_tables || opp_table->regulators ||
> + opp_table->paths)
> + goto skip_clk_only;
> dev_dbg(dev, "%s: old/new frequencies (%lu Hz) are same, nothing to
> do\n",
> __func__, freq);
> ret = 0;
> @@ -919,6 +922,7 @@ int dev_pm_opp_set_rate(struct device *dev,
> unsigned long target_freq)
> goto put_opp_table;
> }
>
> +skip_clk_only:
> temp_freq = old_freq;
> old_opp = _find_freq_ceil(opp_table, &temp_freq);
> if (IS_ERR(old_opp)) {
> @@ -954,8 +958,10 @@ int dev_pm_opp_set_rate(struct device *dev,
> unsigned long target_freq)
> IS_ERR(old_opp) ? NULL : old_opp->supplies,
> opp->supplies);
> } else {
> + ret = 0;
> /* Only frequency scaling */
> - ret = _generic_set_opp_clk_only(dev, clk, freq);
> + if (freq != old_freq)
> + ret = _generic_set_opp_clk_only(dev, clk, freq);
> }
>
> /* Scaling down? Configure required OPPs after frequency */

--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project.

\
 
 \ /
  Last update: 2020-08-10 12:42    [W:0.205 / U:2.928 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site