| Message ID | 20200730120054.1.I5e6f8c262031d0451fe7241b744f4f3111c1ce71@changeid (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | soc: mediatek: Check if power domains can be powered on at boot time | expand |
Matthias, gentle ping on the patch below >>> Thanks! On Thu, Jul 30, 2020 at 12:01 PM Nicolas Boichat <drinkcat@chromium.org> wrote: > > In the error case, where a power domain cannot be powered on > successfully at boot time (in mtk_register_power_domains), > pm_genpd_init would still be called with is_off=false, and the > system would later try to disable the power domain again, triggering > warnings as disabled clocks are disabled again (and other potential > issues). > > Fixes: c84e358718a66f7 ("soc: Mediatek: Add SCPSYS power domain driver") > Signed-off-by: Nicolas Boichat <drinkcat@chromium.org> > > --- > > drivers/soc/mediatek/mtk-scpsys.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/soc/mediatek/mtk-scpsys.c b/drivers/soc/mediatek/mtk-scpsys.c > index f669d3754627dad..0055a52a49733d5 100644 > --- a/drivers/soc/mediatek/mtk-scpsys.c > +++ b/drivers/soc/mediatek/mtk-scpsys.c > @@ -524,6 +524,7 @@ static void mtk_register_power_domains(struct platform_device *pdev, > for (i = 0; i < num; i++) { > struct scp_domain *scpd = &scp->domains[i]; > struct generic_pm_domain *genpd = &scpd->genpd; > + bool on; > > /* > * Initially turn on all domains to make the domains usable > @@ -531,9 +532,9 @@ static void mtk_register_power_domains(struct platform_device *pdev, > * software. The unused domains will be switched off during > * late_init time. > */ > - genpd->power_on(genpd); > + on = genpd->power_on(genpd) >= 0; > > - pm_genpd_init(genpd, NULL, false); > + pm_genpd_init(genpd, NULL, !on); > } > > /* > -- > 2.28.0.rc0.142.g3c755180ce-goog >
Hi Nicolas, Thanks for the patch. On 30/07/2020 06:01, Nicolas Boichat wrote: > In the error case, where a power domain cannot be powered on > successfully at boot time (in mtk_register_power_domains), > pm_genpd_init would still be called with is_off=false, and the > system would later try to disable the power domain again, triggering > warnings as disabled clocks are disabled again (and other potential > issues). > > Fixes: c84e358718a66f7 ("soc: Mediatek: Add SCPSYS power domain driver") > Signed-off-by: Nicolas Boichat <drinkcat@chromium.org> > > --- > > drivers/soc/mediatek/mtk-scpsys.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/soc/mediatek/mtk-scpsys.c b/drivers/soc/mediatek/mtk-scpsys.c > index f669d3754627dad..0055a52a49733d5 100644 > --- a/drivers/soc/mediatek/mtk-scpsys.c > +++ b/drivers/soc/mediatek/mtk-scpsys.c > @@ -524,6 +524,7 @@ static void mtk_register_power_domains(struct platform_device *pdev, > for (i = 0; i < num; i++) { > struct scp_domain *scpd = &scp->domains[i]; > struct generic_pm_domain *genpd = &scpd->genpd; > + bool on; > > /* > * Initially turn on all domains to make the domains usable > @@ -531,9 +532,9 @@ static void mtk_register_power_domains(struct platform_device *pdev, > * software. The unused domains will be switched off during > * late_init time. > */ > - genpd->power_on(genpd); > + on = genpd->power_on(genpd) >= 0; Is this something we expect? On probing we realize that some domains can't be turned on? I understand that this would be a bug in the driver. Therefore we should at most provide a warning instead of working around the bug, hiding it. Or do I got this wrong? Regards, Matthias > > - pm_genpd_init(genpd, NULL, false); > + pm_genpd_init(genpd, NULL, !on); > } > > /* >
Hi, On Tue, Sep 22, 2020 at 1:07 AM Matthias Brugger <matthias.bgg@gmail.com> wrote: > > Hi Nicolas, > > Thanks for the patch. > > On 30/07/2020 06:01, Nicolas Boichat wrote: > > In the error case, where a power domain cannot be powered on > > successfully at boot time (in mtk_register_power_domains), > > pm_genpd_init would still be called with is_off=false, and the > > system would later try to disable the power domain again, triggering > > warnings as disabled clocks are disabled again (and other potential > > issues). > > > > Fixes: c84e358718a66f7 ("soc: Mediatek: Add SCPSYS power domain driver") > > Signed-off-by: Nicolas Boichat <drinkcat@chromium.org> > > > > --- > > > > drivers/soc/mediatek/mtk-scpsys.c | 5 +++-- > > 1 file changed, 3 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/soc/mediatek/mtk-scpsys.c b/drivers/soc/mediatek/mtk-scpsys.c > > index f669d3754627dad..0055a52a49733d5 100644 > > --- a/drivers/soc/mediatek/mtk-scpsys.c > > +++ b/drivers/soc/mediatek/mtk-scpsys.c > > @@ -524,6 +524,7 @@ static void mtk_register_power_domains(struct platform_device *pdev, > > for (i = 0; i < num; i++) { > > struct scp_domain *scpd = &scp->domains[i]; > > struct generic_pm_domain *genpd = &scpd->genpd; > > + bool on; > > > > /* > > * Initially turn on all domains to make the domains usable > > @@ -531,9 +532,9 @@ static void mtk_register_power_domains(struct platform_device *pdev, > > * software. The unused domains will be switched off during > > * late_init time. > > */ > > - genpd->power_on(genpd); > > + on = genpd->power_on(genpd) >= 0; > > Is this something we expect? On probing we realize that some domains can't be > turned on? > > I understand that this would be a bug in the driver. Therefore we should at most > provide a warning instead of working around the bug, hiding it. Or do I got this > wrong? No, you get this right. That's a bug (we see this on unreleased HW), and we will fix it. Now, we already get this (somewhat subtle) error message on boot: mtk-scpsys 10006000.power-controller: Failed to power on domain adsp But without this patch, there is an unbalance later on (that is possibly a bit confusing): [ 6.510811] ------------[ cut here ]------------ [ 6.515417] adsp_sel already disabled [ 6.519089] WARNING: CPU: 5 PID: 180 at drivers/clk/clk.c:958 clk_core_disable+0x1ec/0x22c ... [ 6.658393] clk_core_disable+0x1ec/0x22c [ 6.662395] clk_disable+0x34/0x48 [ 6.665791] scpsys_clk_disable+0x34/0x58 [ 6.669791] scpsys_power_off+0x374/0x3ec [ 6.673790] _genpd_power_off+0x40/0x98 [ 6.677616] genpd_power_off+0x168/0x208 [ 6.681530] genpd_power_off_work_fn+0x38/0x54 [ 6.685964] process_one_work+0x208/0x3c8 [ 6.689964] worker_thread+0x23c/0x3e8 [ 6.693703] kthread+0x11c/0x12c [ 6.696923] ret_from_fork+0x10/0x18 [ 6.700487] ---[ end trace 91ddada49c4d717c ]--- But I get your point, we should probably add something like WARN_ON(!on) to make it clearer, at the time when the issue occurs, that something is not right... Thanks, > Regards, > Matthias > > > > > - pm_genpd_init(genpd, NULL, false); > > + pm_genpd_init(genpd, NULL, !on); > > } > > > > /* > >
diff --git a/drivers/soc/mediatek/mtk-scpsys.c b/drivers/soc/mediatek/mtk-scpsys.c index f669d3754627dad..0055a52a49733d5 100644 --- a/drivers/soc/mediatek/mtk-scpsys.c +++ b/drivers/soc/mediatek/mtk-scpsys.c @@ -524,6 +524,7 @@ static void mtk_register_power_domains(struct platform_device *pdev, for (i = 0; i < num; i++) { struct scp_domain *scpd = &scp->domains[i]; struct generic_pm_domain *genpd = &scpd->genpd; + bool on; /* * Initially turn on all domains to make the domains usable @@ -531,9 +532,9 @@ static void mtk_register_power_domains(struct platform_device *pdev, * software. The unused domains will be switched off during * late_init time. */ - genpd->power_on(genpd); + on = genpd->power_on(genpd) >= 0; - pm_genpd_init(genpd, NULL, false); + pm_genpd_init(genpd, NULL, !on); } /*
In the error case, where a power domain cannot be powered on successfully at boot time (in mtk_register_power_domains), pm_genpd_init would still be called with is_off=false, and the system would later try to disable the power domain again, triggering warnings as disabled clocks are disabled again (and other potential issues). Fixes: c84e358718a66f7 ("soc: Mediatek: Add SCPSYS power domain driver") Signed-off-by: Nicolas Boichat <drinkcat@chromium.org> --- drivers/soc/mediatek/mtk-scpsys.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)