| Message ID | c274500b623b83c00c0460383cbe1cdc7490eeac.1712658693.git.viresh.kumar@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | OPP: Fix required_opp_tables for multiple genpds using same table | expand |
On Tue, Apr 09, 2024 at 04:02:19PM +0530, Viresh Kumar wrote: > The required_opp_tables parsing is not perfect, as the OPP core does the > parsing solely based on the DT node pointers. > > The core sets the required_opp_tables entry to the first OPP table in > the "opp_tables" list, that matches with the node pointer. > > If the target DT OPP table is used by multiple devices and they all > create separate instances of 'struct opp_table' from it, then it is > possible that the required_opp_tables entry may be set to the incorrect > sibling device. > > Unfortunately, there is no clear way to initialize the right values > during the initial parsing and we need to do this at a later point of > time. > > Cross check the OPP table again while the genpds are attached and fix > them if required. > > Also add a new API for the genpd core to fetch the device pointer for > the genpd. > > Cc: Thorsten Leemhuis <regressions@leemhuis.info> > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=218682 > Reported-by: Vladimir Lypak <vladimir.lypak@gmail.com> > Co-developed-by: Vladimir Lypak <vladimir.lypak@gmail.com> > Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> > --- > Vladimir Lypak, > > Can you please give this a try and confirm that it fixes the issue. > > drivers/opp/core.c | 31 ++++++++++++++++++++++++++++++- > drivers/pmdomain/core.c | 10 ++++++++++ > include/linux/pm_domain.h | 6 ++++++ > 3 files changed, 46 insertions(+), 1 deletion(-) > > diff --git a/drivers/opp/core.c b/drivers/opp/core.c > index e233734b7220..1f64b703b744 100644 > --- a/drivers/opp/core.c > +++ b/drivers/opp/core.c > @@ -2394,7 +2394,8 @@ static void _opp_detach_genpd(struct opp_table *opp_table) > static int _opp_attach_genpd(struct opp_table *opp_table, struct device *dev, > const char * const *names, struct device ***virt_devs) > { > - struct device *virt_dev; > + struct device *virt_dev, *gdev; > + struct opp_table *genpd_table; > int index = 0, ret = -EINVAL; > const char * const *name = names; > > @@ -2427,6 +2428,34 @@ static int _opp_attach_genpd(struct opp_table *opp_table, struct device *dev, > goto err; > } > > + /* > + * The required_opp_tables parsing is not perfect, as the OPP > + * core does the parsing solely based on the DT node pointers. > + * The core sets the required_opp_tables entry to the first OPP > + * table in the "opp_tables" list, that matches with the node > + * pointer. > + * > + * If the target DT OPP table is used by multiple devices and > + * they all create separate instances of 'struct opp_table' from > + * it, then it is possible that the required_opp_tables entry > + * may be set to the incorrect sibling device. > + * > + * Cross check it again and fix if required. > + */ > + gdev = dev_to_genpd_dev(virt_dev); > + if (!IS_ERR(gdev)) > + return PTR_ERR(gdev); This condition shouldn't be inverted. It returns if gdev is valid. With this bit corrected patch fixes the issue.
On 09.04.24 12:32, Viresh Kumar wrote: > The required_opp_tables parsing is not perfect, as the OPP core does the > parsing solely based on the DT node pointers. > > The core sets the required_opp_tables entry to the first OPP table in > the "opp_tables" list, that matches with the node pointer. > > [...] > Cc: Thorsten Leemhuis <regressions@leemhuis.info> > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=218682 > Reported-by: Vladimir Lypak <vladimir.lypak@gmail.com> s/Bugzilla/Closes/ here please. See submitting-patches for details. And ideally it should first be "Reported-by" and then "Closes". Ciao, Thorsten
diff --git a/drivers/opp/core.c b/drivers/opp/core.c index e233734b7220..1f64b703b744 100644 --- a/drivers/opp/core.c +++ b/drivers/opp/core.c @@ -2394,7 +2394,8 @@ static void _opp_detach_genpd(struct opp_table *opp_table) static int _opp_attach_genpd(struct opp_table *opp_table, struct device *dev, const char * const *names, struct device ***virt_devs) { - struct device *virt_dev; + struct device *virt_dev, *gdev; + struct opp_table *genpd_table; int index = 0, ret = -EINVAL; const char * const *name = names; @@ -2427,6 +2428,34 @@ static int _opp_attach_genpd(struct opp_table *opp_table, struct device *dev, goto err; } + /* + * The required_opp_tables parsing is not perfect, as the OPP + * core does the parsing solely based on the DT node pointers. + * The core sets the required_opp_tables entry to the first OPP + * table in the "opp_tables" list, that matches with the node + * pointer. + * + * If the target DT OPP table is used by multiple devices and + * they all create separate instances of 'struct opp_table' from + * it, then it is possible that the required_opp_tables entry + * may be set to the incorrect sibling device. + * + * Cross check it again and fix if required. + */ + gdev = dev_to_genpd_dev(virt_dev); + if (!IS_ERR(gdev)) + return PTR_ERR(gdev); + + genpd_table = _find_opp_table(gdev); + if (!IS_ERR(genpd_table)) { + if (genpd_table != opp_table->required_opp_tables[index]) { + dev_pm_opp_put_opp_table(opp_table->required_opp_tables[index]); + opp_table->required_opp_tables[index] = genpd_table; + } else { + dev_pm_opp_put_opp_table(genpd_table); + } + } + /* * Add the virtual genpd device as a user of the OPP table, so * we can call dev_pm_opp_set_opp() on it directly. diff --git a/drivers/pmdomain/core.c b/drivers/pmdomain/core.c index 4215ffd9b11c..c40eda92a85a 100644 --- a/drivers/pmdomain/core.c +++ b/drivers/pmdomain/core.c @@ -184,6 +184,16 @@ static struct generic_pm_domain *dev_to_genpd(struct device *dev) return pd_to_genpd(dev->pm_domain); } +struct device *dev_to_genpd_dev(struct device *dev) +{ + struct generic_pm_domain *genpd = dev_to_genpd(dev); + + if (IS_ERR(genpd)) + return ERR_CAST(genpd); + + return &genpd->dev; +} + static int genpd_stop_dev(const struct generic_pm_domain *genpd, struct device *dev) { diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index 772d3280d35f..f24546a3d3db 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -260,6 +260,7 @@ int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd, int pm_genpd_init(struct generic_pm_domain *genpd, struct dev_power_governor *gov, bool is_off); int pm_genpd_remove(struct generic_pm_domain *genpd); +struct device *dev_to_genpd_dev(struct device *dev); int dev_pm_genpd_set_performance_state(struct device *dev, unsigned int state); int dev_pm_genpd_add_notifier(struct device *dev, struct notifier_block *nb); int dev_pm_genpd_remove_notifier(struct device *dev); @@ -307,6 +308,11 @@ static inline int pm_genpd_remove(struct generic_pm_domain *genpd) return -EOPNOTSUPP; } +static inline struct device *dev_to_genpd_dev(struct device *dev) +{ + return ERR_PTR(-EOPNOTSUPP); +} + static inline int dev_pm_genpd_set_performance_state(struct device *dev, unsigned int state) {
The required_opp_tables parsing is not perfect, as the OPP core does the parsing solely based on the DT node pointers. The core sets the required_opp_tables entry to the first OPP table in the "opp_tables" list, that matches with the node pointer. If the target DT OPP table is used by multiple devices and they all create separate instances of 'struct opp_table' from it, then it is possible that the required_opp_tables entry may be set to the incorrect sibling device. Unfortunately, there is no clear way to initialize the right values during the initial parsing and we need to do this at a later point of time. Cross check the OPP table again while the genpds are attached and fix them if required. Also add a new API for the genpd core to fetch the device pointer for the genpd. Cc: Thorsten Leemhuis <regressions@leemhuis.info> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=218682 Reported-by: Vladimir Lypak <vladimir.lypak@gmail.com> Co-developed-by: Vladimir Lypak <vladimir.lypak@gmail.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> --- Vladimir Lypak, Can you please give this a try and confirm that it fixes the issue. drivers/opp/core.c | 31 ++++++++++++++++++++++++++++++- drivers/pmdomain/core.c | 10 ++++++++++ include/linux/pm_domain.h | 6 ++++++ 3 files changed, 46 insertions(+), 1 deletion(-)