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clk: mediatek: mt8183: Only enable runtime PM on mt8183-mfgcfg

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Commit 2f7b1d8b55 ("clk: mediatek: Do a runtime PM get on controllers
during probe") enabled runtime PM for all mediatek clock controllers,
but this introduced an issue on the resume path.

If a device resumes earlier than the clock controller and calls
clk_prepare() when runtime PM is enabled on the controller, it will end
up calling clk_pm_runtime_get(). But the subsequent
pm_runtime_resume_and_get() call will fail because the runtime PM is
temporarily disabled during suspend.

To workaround this, introduce a need_runtime_pm flag and only enable it
on mt8183-mfgcfg, which is the driver that observed deadlock previously.
Hopefully mt8183-cfgcfg won't run into the issue at the resume stage
because the GPU should have stopped rendering before the system calls
suspend.

Fixes: 2f7b1d8b55 ("clk: mediatek: Do a runtime PM get on controllers during probe")
Signed-off-by: Pin-yen Lin <treapking@chromium.org>
Link: https://lore.kernel.org/r/20240613120357.1043342-1-treapking@chromium.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
This commit is contained in:
Pin-yen Lin 2024-06-13 20:02:28 +08:00 committed by Stephen Boyd
parent f7275fdf94
commit 878e845d8d
3 changed files with 17 additions and 10 deletions
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1
drivers/clk/mediatek/clk-mt8183-mfgcfg.c
View File

@ -29,6 +29,7 @@ static const struct mtk_gate mfg_clks[] = {
static const struct mtk_clk_desc mfg_desc = {
.clks = mfg_clks,
.num_clks = ARRAY_SIZE(mfg_clks),
.need_runtime_pm = true,
};
static const struct of_device_id of_match_clk_mt8183_mfg[] = {

24
drivers/clk/mediatek/clk-mtk.c
View File

@ -496,14 +496,16 @@ static int __mtk_clk_simple_probe(struct platform_device *pdev,
}
devm_pm_runtime_enable(&pdev->dev);
/*
* Do a pm_runtime_resume_and_get() to workaround a possible
* deadlock between clk_register() and the genpd framework.
*/
r = pm_runtime_resume_and_get(&pdev->dev);
if (r)
return r;
if (mcd->need_runtime_pm) {
devm_pm_runtime_enable(&pdev->dev);
/*
* Do a pm_runtime_resume_and_get() to workaround a possible
* deadlock between clk_register() and the genpd framework.
*/
r = pm_runtime_resume_and_get(&pdev->dev);
if (r)
return r;
}
/* Calculate how many clk_hw_onecell_data entries to allocate */
num_clks = mcd->num_clks + mcd->num_composite_clks;
@ -585,7 +587,8 @@ static int __mtk_clk_simple_probe(struct platform_device *pdev,
goto unregister_clks;
}
pm_runtime_put(&pdev->dev);
if (mcd->need_runtime_pm)
pm_runtime_put(&pdev->dev);
return r;
@ -618,7 +621,8 @@ free_base:
if (mcd->shared_io && base)
iounmap(base);
pm_runtime_put(&pdev->dev);
if (mcd->need_runtime_pm)
pm_runtime_put(&pdev->dev);
return r;
}

2
drivers/clk/mediatek/clk-mtk.h
View File

@ -237,6 +237,8 @@ struct mtk_clk_desc {
int (*clk_notifier_func)(struct device *dev, struct clk *clk);
unsigned int mfg_clk_idx;
bool need_runtime_pm;
};
int mtk_clk_pdev_probe(struct platform_device *pdev);