[2/3] clk: qcom: lpass-sc7180: Fix pm_runtime usage
Commit Message
The sc7180 lpass clock controller's pm_runtime usage wasn't broken
quite as spectacularly as the sc7280's pm_runtime usage, but it was
still broken. Putting some printouts in at boot showed me this (with
serial console enabled, which makes the prints slow and thus changes
timing):
[ 3.109951] DOUG: my_pm_clk_resume, usage=1
[ 3.114767] DOUG: my_pm_clk_resume, usage=1
[ 3.664443] DOUG: my_pm_clk_suspend, usage=0
[ 3.897566] DOUG: my_pm_clk_suspend, usage=0
[ 3.910137] DOUG: my_pm_clk_resume, usage=1
[ 3.923217] DOUG: my_pm_clk_resume, usage=0
[ 4.440116] DOUG: my_pm_clk_suspend, usage=-1
[ 4.444982] DOUG: my_pm_clk_suspend, usage=0
[ 14.170501] DOUG: my_pm_clk_resume, usage=1
[ 14.176245] DOUG: my_pm_clk_resume, usage=0
...or this w/out serial console:
[ 0.556139] DOUG: my_pm_clk_resume, usage=1
[ 0.556279] DOUG: my_pm_clk_resume, usage=1
[ 1.058422] DOUG: my_pm_clk_suspend, usage=-1
[ 1.058464] DOUG: my_pm_clk_suspend, usage=0
[ 1.186250] DOUG: my_pm_clk_resume, usage=1
[ 1.186292] DOUG: my_pm_clk_resume, usage=0
[ 1.731536] DOUG: my_pm_clk_suspend, usage=-1
[ 1.731557] DOUG: my_pm_clk_suspend, usage=0
[ 10.288910] DOUG: my_pm_clk_resume, usage=1
[ 10.289496] DOUG: my_pm_clk_resume, usage=0
It seems to be doing roughly the right sequence of calls, but just
like with sc7280 this is more by luck than anything. Having a usage of
-1 is just not OK.
Let's fix this like we did with sc7280.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
---
drivers/clk/qcom/lpasscorecc-sc7180.c | 24 ++++++++++++++++--------
1 file changed, 16 insertions(+), 8 deletions(-)
Comments
Quoting Douglas Anderson (2022-11-04 06:56:29)
> The sc7180 lpass clock controller's pm_runtime usage wasn't broken
> quite as spectacularly as the sc7280's pm_runtime usage, but it was
> still broken. Putting some printouts in at boot showed me this (with
> serial console enabled, which makes the prints slow and thus changes
> timing):
> [ 3.109951] DOUG: my_pm_clk_resume, usage=1
> [ 3.114767] DOUG: my_pm_clk_resume, usage=1
> [ 3.664443] DOUG: my_pm_clk_suspend, usage=0
> [ 3.897566] DOUG: my_pm_clk_suspend, usage=0
> [ 3.910137] DOUG: my_pm_clk_resume, usage=1
> [ 3.923217] DOUG: my_pm_clk_resume, usage=0
> [ 4.440116] DOUG: my_pm_clk_suspend, usage=-1
> [ 4.444982] DOUG: my_pm_clk_suspend, usage=0
> [ 14.170501] DOUG: my_pm_clk_resume, usage=1
> [ 14.176245] DOUG: my_pm_clk_resume, usage=0
>
> ...or this w/out serial console:
> [ 0.556139] DOUG: my_pm_clk_resume, usage=1
> [ 0.556279] DOUG: my_pm_clk_resume, usage=1
> [ 1.058422] DOUG: my_pm_clk_suspend, usage=-1
> [ 1.058464] DOUG: my_pm_clk_suspend, usage=0
> [ 1.186250] DOUG: my_pm_clk_resume, usage=1
> [ 1.186292] DOUG: my_pm_clk_resume, usage=0
> [ 1.731536] DOUG: my_pm_clk_suspend, usage=-1
> [ 1.731557] DOUG: my_pm_clk_suspend, usage=0
> [ 10.288910] DOUG: my_pm_clk_resume, usage=1
> [ 10.289496] DOUG: my_pm_clk_resume, usage=0
>
> It seems to be doing roughly the right sequence of calls, but just
> like with sc7280 this is more by luck than anything. Having a usage of
> -1 is just not OK.
>
> Let's fix this like we did with sc7280.
Any Fixes tag?
>
> Signed-off-by: Douglas Anderson <dianders@chromium.org>
> ---
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Hi,
On Fri, Nov 4, 2022 at 2:19 PM Stephen Boyd <swboyd@chromium.org> wrote:
>
> Quoting Douglas Anderson (2022-11-04 06:56:29)
> > The sc7180 lpass clock controller's pm_runtime usage wasn't broken
> > quite as spectacularly as the sc7280's pm_runtime usage, but it was
> > still broken. Putting some printouts in at boot showed me this (with
> > serial console enabled, which makes the prints slow and thus changes
> > timing):
> > [ 3.109951] DOUG: my_pm_clk_resume, usage=1
> > [ 3.114767] DOUG: my_pm_clk_resume, usage=1
> > [ 3.664443] DOUG: my_pm_clk_suspend, usage=0
> > [ 3.897566] DOUG: my_pm_clk_suspend, usage=0
> > [ 3.910137] DOUG: my_pm_clk_resume, usage=1
> > [ 3.923217] DOUG: my_pm_clk_resume, usage=0
> > [ 4.440116] DOUG: my_pm_clk_suspend, usage=-1
> > [ 4.444982] DOUG: my_pm_clk_suspend, usage=0
> > [ 14.170501] DOUG: my_pm_clk_resume, usage=1
> > [ 14.176245] DOUG: my_pm_clk_resume, usage=0
> >
> > ...or this w/out serial console:
> > [ 0.556139] DOUG: my_pm_clk_resume, usage=1
> > [ 0.556279] DOUG: my_pm_clk_resume, usage=1
> > [ 1.058422] DOUG: my_pm_clk_suspend, usage=-1
> > [ 1.058464] DOUG: my_pm_clk_suspend, usage=0
> > [ 1.186250] DOUG: my_pm_clk_resume, usage=1
> > [ 1.186292] DOUG: my_pm_clk_resume, usage=0
> > [ 1.731536] DOUG: my_pm_clk_suspend, usage=-1
> > [ 1.731557] DOUG: my_pm_clk_suspend, usage=0
> > [ 10.288910] DOUG: my_pm_clk_resume, usage=1
> > [ 10.289496] DOUG: my_pm_clk_resume, usage=0
> >
> > It seems to be doing roughly the right sequence of calls, but just
> > like with sc7280 this is more by luck than anything. Having a usage of
> > -1 is just not OK.
> >
> > Let's fix this like we did with sc7280.
>
> Any Fixes tag?
Ah, right. I guess the most obvious one is actually:
Fixes: ce8c195e652f ("clk: qcom: lpasscc: Introduce pm autosuspend for SC7180")
That's what got us going negative. One could _sorta_ make the argument
for a "Fixes" tag all the way to the start of the driver, though. The
driver never did a pm_runtime_get() during probe and so there was (I
guess) a chance that some of the bare register writes in probe could
have been unclocked. I'm not aware of that ever being a problem, so I
guess just the above "Fixes" is fine.
> > Signed-off-by: Douglas Anderson <dianders@chromium.org>
> > ---
>
> Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Thanks! Yell if you want me to spin a v2 with the Fixes in place.
-Doug
@@ -356,7 +356,7 @@ static const struct qcom_cc_desc lpass_audio_hm_sc7180_desc = {
.num_gdscs = ARRAY_SIZE(lpass_audio_hm_sc7180_gdscs),
};
-static int lpass_create_pm_clks(struct platform_device *pdev)
+static int lpass_setup_runtime_pm(struct platform_device *pdev)
{
int ret;
@@ -375,7 +375,7 @@ static int lpass_create_pm_clks(struct platform_device *pdev)
if (ret < 0)
dev_err(&pdev->dev, "failed to acquire iface clock\n");
- return ret;
+ return pm_runtime_resume_and_get(&pdev->dev);
}
static int lpass_core_cc_sc7180_probe(struct platform_device *pdev)
@@ -384,7 +384,7 @@ static int lpass_core_cc_sc7180_probe(struct platform_device *pdev)
struct regmap *regmap;
int ret;
- ret = lpass_create_pm_clks(pdev);
+ ret = lpass_setup_runtime_pm(pdev);
if (ret)
return ret;
@@ -392,12 +392,14 @@ static int lpass_core_cc_sc7180_probe(struct platform_device *pdev)
desc = &lpass_audio_hm_sc7180_desc;
ret = qcom_cc_probe_by_index(pdev, 1, desc);
if (ret)
- return ret;
+ goto exit;
lpass_core_cc_sc7180_regmap_config.name = "lpass_core_cc";
regmap = qcom_cc_map(pdev, &lpass_core_cc_sc7180_desc);
- if (IS_ERR(regmap))
- return PTR_ERR(regmap);
+ if (IS_ERR(regmap)) {
+ ret = PTR_ERR(regmap);
+ goto exit;
+ }
/*
* Keep the CLK always-ON
@@ -415,6 +417,7 @@ static int lpass_core_cc_sc7180_probe(struct platform_device *pdev)
ret = qcom_cc_really_probe(pdev, &lpass_core_cc_sc7180_desc, regmap);
pm_runtime_mark_last_busy(&pdev->dev);
+exit:
pm_runtime_put_autosuspend(&pdev->dev);
return ret;
@@ -425,14 +428,19 @@ static int lpass_hm_core_probe(struct platform_device *pdev)
const struct qcom_cc_desc *desc;
int ret;
- ret = lpass_create_pm_clks(pdev);
+ ret = lpass_setup_runtime_pm(pdev);
if (ret)
return ret;
lpass_core_cc_sc7180_regmap_config.name = "lpass_hm_core";
desc = &lpass_core_hm_sc7180_desc;
- return qcom_cc_probe_by_index(pdev, 0, desc);
+ ret = qcom_cc_probe_by_index(pdev, 0, desc);
+
+ pm_runtime_mark_last_busy(&pdev->dev);
+ pm_runtime_put_autosuspend(&pdev->dev);
+
+ return ret;
}
static const struct of_device_id lpass_hm_sc7180_match_table[] = {