| Message ID | 20201217180638.22748-16-digetx@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Introduce core voltage scaling for NVIDIA Tegra20/30 SoCs | expand |
On 17-12-20, 21:06, Dmitry Osipenko wrote: > Support set_opp() customization without requiring to use regulators. This > is needed by drivers which want to use dev_pm_opp_set_rate() for changing > rates of a multiple clocks and don't need to touch regulator. > > One example is NVIDIA Tegra30/114 SoCs which have two sibling 3D hardware > units which should be use to the same clock rate, meanwhile voltage > scaling is done using a power domain. In this case OPP table doesn't have > a regulator, causing a NULL dereference in _set_opp_custom(). > > Signed-off-by: Dmitry Osipenko <digetx@gmail.com> > --- > drivers/opp/core.c | 16 ++++++++++++---- > 1 file changed, 12 insertions(+), 4 deletions(-) > > diff --git a/drivers/opp/core.c b/drivers/opp/core.c > index 3d02fe33630b..625dae7a5ecb 100644 > --- a/drivers/opp/core.c > +++ b/drivers/opp/core.c > @@ -828,17 +828,25 @@ static int _set_opp_custom(const struct opp_table *opp_table, > struct dev_pm_opp_supply *old_supply, > struct dev_pm_opp_supply *new_supply) > { > - struct dev_pm_set_opp_data *data; > + struct dev_pm_set_opp_data *data, tmp_data; > + unsigned int regulator_count; > int size; > > - data = opp_table->set_opp_data; > + if (opp_table->set_opp_data) { > + data = opp_table->set_opp_data; > + regulator_count = opp_table->regulator_count; > + } else { > + data = &tmp_data; > + regulator_count = 0; > + } > + > data->regulators = opp_table->regulators; > - data->regulator_count = opp_table->regulator_count; > + data->regulator_count = regulator_count; > data->clk = opp_table->clk; > data->dev = dev; > > data->old_opp.rate = old_freq; > - size = sizeof(*old_supply) * opp_table->regulator_count; > + size = sizeof(*old_supply) * regulator_count; > if (!old_supply) > memset(data->old_opp.supplies, 0, size); > else I don't see you making use of this in this patchset. How did you get this to crash ?
22.12.2020 12:01, Viresh Kumar пишет: > On 17-12-20, 21:06, Dmitry Osipenko wrote: >> Support set_opp() customization without requiring to use regulators. This >> is needed by drivers which want to use dev_pm_opp_set_rate() for changing >> rates of a multiple clocks and don't need to touch regulator. >> >> One example is NVIDIA Tegra30/114 SoCs which have two sibling 3D hardware >> units which should be use to the same clock rate, meanwhile voltage >> scaling is done using a power domain. In this case OPP table doesn't have >> a regulator, causing a NULL dereference in _set_opp_custom(). >> >> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> >> --- >> drivers/opp/core.c | 16 ++++++++++++---- >> 1 file changed, 12 insertions(+), 4 deletions(-) >> >> diff --git a/drivers/opp/core.c b/drivers/opp/core.c >> index 3d02fe33630b..625dae7a5ecb 100644 >> --- a/drivers/opp/core.c >> +++ b/drivers/opp/core.c >> @@ -828,17 +828,25 @@ static int _set_opp_custom(const struct opp_table *opp_table, >> struct dev_pm_opp_supply *old_supply, >> struct dev_pm_opp_supply *new_supply) >> { >> - struct dev_pm_set_opp_data *data; >> + struct dev_pm_set_opp_data *data, tmp_data; >> + unsigned int regulator_count; >> int size; >> >> - data = opp_table->set_opp_data; >> + if (opp_table->set_opp_data) { >> + data = opp_table->set_opp_data; >> + regulator_count = opp_table->regulator_count; >> + } else { >> + data = &tmp_data; >> + regulator_count = 0; >> + } >> + >> data->regulators = opp_table->regulators; >> - data->regulator_count = opp_table->regulator_count; >> + data->regulator_count = regulator_count; >> data->clk = opp_table->clk; >> data->dev = dev; >> >> data->old_opp.rate = old_freq; >> - size = sizeof(*old_supply) * opp_table->regulator_count; >> + size = sizeof(*old_supply) * regulator_count; >> if (!old_supply) >> memset(data->old_opp.supplies, 0, size); >> else > > I don't see you making use of this in this patchset. How did you get this to > crash ? > Please see patch 38 where 3d driver makes use of devm_pm_opp_register_set_opp_helper(). The opp_table->set_opp_data=NULL and opp_table->regulator_count=-1 if OPP table doesn't use a regulator, hence the crash happens.
On 17-12-20, 21:06, Dmitry Osipenko wrote: > Support set_opp() customization without requiring to use regulators. This > is needed by drivers which want to use dev_pm_opp_set_rate() for changing > rates of a multiple clocks and don't need to touch regulator. > > One example is NVIDIA Tegra30/114 SoCs which have two sibling 3D hardware > units which should be use to the same clock rate, meanwhile voltage > scaling is done using a power domain. In this case OPP table doesn't have > a regulator, causing a NULL dereference in _set_opp_custom(). > > Signed-off-by: Dmitry Osipenko <digetx@gmail.com> > --- > drivers/opp/core.c | 16 ++++++++++++---- > 1 file changed, 12 insertions(+), 4 deletions(-) > > diff --git a/drivers/opp/core.c b/drivers/opp/core.c > index 3d02fe33630b..625dae7a5ecb 100644 > --- a/drivers/opp/core.c > +++ b/drivers/opp/core.c > @@ -828,17 +828,25 @@ static int _set_opp_custom(const struct opp_table *opp_table, > struct dev_pm_opp_supply *old_supply, > struct dev_pm_opp_supply *new_supply) > { > - struct dev_pm_set_opp_data *data; > + struct dev_pm_set_opp_data *data, tmp_data; > + unsigned int regulator_count; > int size; > > - data = opp_table->set_opp_data; > + if (opp_table->set_opp_data) { > + data = opp_table->set_opp_data; > + regulator_count = opp_table->regulator_count; > + } else { > + data = &tmp_data; > + regulator_count = 0; > + } > + We should use the same structure, you can add some checks but not replace the structure altogether. > data->regulators = opp_table->regulators; > - data->regulator_count = opp_table->regulator_count; > + data->regulator_count = regulator_count; > data->clk = opp_table->clk; > data->dev = dev; > > data->old_opp.rate = old_freq; > - size = sizeof(*old_supply) * opp_table->regulator_count; > + size = sizeof(*old_supply) * regulator_count; > if (!old_supply) > memset(data->old_opp.supplies, 0, size); > else
23.12.2020 09:01, Viresh Kumar пишет: > On 17-12-20, 21:06, Dmitry Osipenko wrote: >> Support set_opp() customization without requiring to use regulators. This >> is needed by drivers which want to use dev_pm_opp_set_rate() for changing >> rates of a multiple clocks and don't need to touch regulator. >> >> One example is NVIDIA Tegra30/114 SoCs which have two sibling 3D hardware >> units which should be use to the same clock rate, meanwhile voltage >> scaling is done using a power domain. In this case OPP table doesn't have >> a regulator, causing a NULL dereference in _set_opp_custom(). >> >> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> >> --- >> drivers/opp/core.c | 16 ++++++++++++---- >> 1 file changed, 12 insertions(+), 4 deletions(-) >> >> diff --git a/drivers/opp/core.c b/drivers/opp/core.c >> index 3d02fe33630b..625dae7a5ecb 100644 >> --- a/drivers/opp/core.c >> +++ b/drivers/opp/core.c >> @@ -828,17 +828,25 @@ static int _set_opp_custom(const struct opp_table *opp_table, >> struct dev_pm_opp_supply *old_supply, >> struct dev_pm_opp_supply *new_supply) >> { >> - struct dev_pm_set_opp_data *data; >> + struct dev_pm_set_opp_data *data, tmp_data; >> + unsigned int regulator_count; >> int size; >> >> - data = opp_table->set_opp_data; >> + if (opp_table->set_opp_data) { >> + data = opp_table->set_opp_data; >> + regulator_count = opp_table->regulator_count; >> + } else { >> + data = &tmp_data; >> + regulator_count = 0; >> + } >> + > > We should use the same structure, you can add some checks but not replace the > structure altogether. Well, there is no "same structure", the opp_table->set_opp_data is NULL there. I can re-write it like this if it looks better to you: static int _set_opp_custom(...) { struct dev_pm_set_opp_data *data; unsigned int regulator_count; int size; + if (!opp_table->set_opp_data) { + struct dev_pm_set_opp_data freq_data = {}; + + freq_data.dev = dev; + freq_data.clk = opp_table->clk; + freq_data.new_opp.rate = freq; + freq_data.old_opp.rate = old_freq; + + return opp_table->set_opp(&freq_data); + }
On 23-12-20, 23:38, Dmitry Osipenko wrote: > Well, there is no "same structure", the opp_table->set_opp_data is NULL > there. Right, I saw that yesterday. What I meant was that we need to start allocating the structure for this case now.
24.12.2020 07:10, Viresh Kumar пишет: > On 23-12-20, 23:38, Dmitry Osipenko wrote: >> Well, there is no "same structure", the opp_table->set_opp_data is NULL >> there. > > Right, I saw that yesterday. What I meant was that we need to start allocating > the structure for this case now. > Okay, that will be a bit bigger change than this v2. I'll try it implement yours suggestion in the next revision, thanks.
diff --git a/drivers/opp/core.c b/drivers/opp/core.c index 3d02fe33630b..625dae7a5ecb 100644 --- a/drivers/opp/core.c +++ b/drivers/opp/core.c @@ -828,17 +828,25 @@ static int _set_opp_custom(const struct opp_table *opp_table, struct dev_pm_opp_supply *old_supply, struct dev_pm_opp_supply *new_supply) { - struct dev_pm_set_opp_data *data; + struct dev_pm_set_opp_data *data, tmp_data; + unsigned int regulator_count; int size; - data = opp_table->set_opp_data; + if (opp_table->set_opp_data) { + data = opp_table->set_opp_data; + regulator_count = opp_table->regulator_count; + } else { + data = &tmp_data; + regulator_count = 0; + } + data->regulators = opp_table->regulators; - data->regulator_count = opp_table->regulator_count; + data->regulator_count = regulator_count; data->clk = opp_table->clk; data->dev = dev; data->old_opp.rate = old_freq; - size = sizeof(*old_supply) * opp_table->regulator_count; + size = sizeof(*old_supply) * regulator_count; if (!old_supply) memset(data->old_opp.supplies, 0, size); else
Support set_opp() customization without requiring to use regulators. This is needed by drivers which want to use dev_pm_opp_set_rate() for changing rates of a multiple clocks and don't need to touch regulator. One example is NVIDIA Tegra30/114 SoCs which have two sibling 3D hardware units which should be use to the same clock rate, meanwhile voltage scaling is done using a power domain. In this case OPP table doesn't have a regulator, causing a NULL dereference in _set_opp_custom(). Signed-off-by: Dmitry Osipenko <digetx@gmail.com> --- drivers/opp/core.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-)