| Message ID | 20191016145756.16004-2-s.nawrocki@samsung.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v5,1/4] PM / OPP: Support adjusting OPP voltages at runtime | expand |
On 16-10-19, 16:57, Sylwester Nawrocki wrote: > From: Stephen Boyd <sboyd@codeaurora.org> > > On some SoCs the Adaptive Voltage Scaling (AVS) technique is > employed to optimize the operating voltage of a device. At a > given frequency, the hardware monitors dynamic factors and either > makes a suggestion for how much to adjust a voltage for the > current frequency, or it automatically adjusts the voltage > without software intervention. Add an API to the OPP library for > the former case, so that AVS type devices can update the voltages > for an OPP when the hardware determines the voltage should > change. The assumption is that drivers like CPUfreq or devfreq > will register for the OPP notifiers and adjust the voltage > according to suggestions that AVS makes. > > This patch is derived from [1] submitted by Stephen. > [1] https://lore.kernel.org/patchwork/patch/599279/ > > Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> > Signed-off-by: Roger Lu <roger.lu@mediatek.com> > [s.nawrocki@samsung.com: added handling of OPP min/max voltage] > Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> > --- > drivers/opp/core.c | 69 ++++++++++++++++++++++++++++++++++++++++++ > include/linux/pm_opp.h | 13 ++++++++ > 2 files changed, 82 insertions(+) Applied. Thanks.
On Thu, Oct 17, 2019 at 12:12:58PM +0530, Viresh Kumar wrote: > On 16-10-19, 16:57, Sylwester Nawrocki wrote: > > From: Stephen Boyd <sboyd@codeaurora.org> > > > > On some SoCs the Adaptive Voltage Scaling (AVS) technique is > > employed to optimize the operating voltage of a device. At a > > given frequency, the hardware monitors dynamic factors and either > > makes a suggestion for how much to adjust a voltage for the > > current frequency, or it automatically adjusts the voltage > > without software intervention. Add an API to the OPP library for > > the former case, so that AVS type devices can update the voltages > > for an OPP when the hardware determines the voltage should > > change. The assumption is that drivers like CPUfreq or devfreq > > will register for the OPP notifiers and adjust the voltage > > according to suggestions that AVS makes. > > > > This patch is derived from [1] submitted by Stephen. > > [1] https://lore.kernel.org/patchwork/patch/599279/ > > > > Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> > > Signed-off-by: Roger Lu <roger.lu@mediatek.com> > > [s.nawrocki@samsung.com: added handling of OPP min/max voltage] > > Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> > > --- > > drivers/opp/core.c | 69 ++++++++++++++++++++++++++++++++++++++++++ > > include/linux/pm_opp.h | 13 ++++++++ > > 2 files changed, 82 insertions(+) > > Applied. Thanks. Hi Viresh, Can you provide a stable tag with this patch so I can take soc/samsung driver? Best regards, Krzysztof
On 21-10-19, 13:23, Krzysztof Kozlowski wrote: > On Thu, Oct 17, 2019 at 12:12:58PM +0530, Viresh Kumar wrote: > > On 16-10-19, 16:57, Sylwester Nawrocki wrote: > > > From: Stephen Boyd <sboyd@codeaurora.org> > > > > > > On some SoCs the Adaptive Voltage Scaling (AVS) technique is > > > employed to optimize the operating voltage of a device. At a > > > given frequency, the hardware monitors dynamic factors and either > > > makes a suggestion for how much to adjust a voltage for the > > > current frequency, or it automatically adjusts the voltage > > > without software intervention. Add an API to the OPP library for > > > the former case, so that AVS type devices can update the voltages > > > for an OPP when the hardware determines the voltage should > > > change. The assumption is that drivers like CPUfreq or devfreq > > > will register for the OPP notifiers and adjust the voltage > > > according to suggestions that AVS makes. > > > > > > This patch is derived from [1] submitted by Stephen. > > > [1] https://lore.kernel.org/patchwork/patch/599279/ > > > > > > Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> > > > Signed-off-by: Roger Lu <roger.lu@mediatek.com> > > > [s.nawrocki@samsung.com: added handling of OPP min/max voltage] > > > Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> > > > --- > > > drivers/opp/core.c | 69 ++++++++++++++++++++++++++++++++++++++++++ > > > include/linux/pm_opp.h | 13 ++++++++ > > > 2 files changed, 82 insertions(+) > > > > Applied. Thanks. > > Hi Viresh, > > Can you provide a stable tag with this patch so I can take soc/samsung > driver? opp-5.4-support-adjust-voltages
On Tue, Oct 22, 2019 at 07:53:41AM +0530, Viresh Kumar wrote: > On 21-10-19, 13:23, Krzysztof Kozlowski wrote: > > On Thu, Oct 17, 2019 at 12:12:58PM +0530, Viresh Kumar wrote: > > > On 16-10-19, 16:57, Sylwester Nawrocki wrote: > > > > From: Stephen Boyd <sboyd@codeaurora.org> > > > > > > > > On some SoCs the Adaptive Voltage Scaling (AVS) technique is > > > > employed to optimize the operating voltage of a device. At a > > > > given frequency, the hardware monitors dynamic factors and either > > > > makes a suggestion for how much to adjust a voltage for the > > > > current frequency, or it automatically adjusts the voltage > > > > without software intervention. Add an API to the OPP library for > > > > the former case, so that AVS type devices can update the voltages > > > > for an OPP when the hardware determines the voltage should > > > > change. The assumption is that drivers like CPUfreq or devfreq > > > > will register for the OPP notifiers and adjust the voltage > > > > according to suggestions that AVS makes. > > > > > > > > This patch is derived from [1] submitted by Stephen. > > > > [1] https://lore.kernel.org/patchwork/patch/599279/ > > > > > > > > Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> > > > > Signed-off-by: Roger Lu <roger.lu@mediatek.com> > > > > [s.nawrocki@samsung.com: added handling of OPP min/max voltage] > > > > Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> > > > > --- > > > > drivers/opp/core.c | 69 ++++++++++++++++++++++++++++++++++++++++++ > > > > include/linux/pm_opp.h | 13 ++++++++ > > > > 2 files changed, 82 insertions(+) > > > > > > Applied. Thanks. > > > > Hi Viresh, > > > > Can you provide a stable tag with this patch so I can take soc/samsung > > driver? > > opp-5.4-support-adjust-voltages Thanks, merged. Best regards, Krzysztof
diff --git a/drivers/opp/core.c b/drivers/opp/core.c index 3b7ffd0234e9..f38b3be85072 100644 --- a/drivers/opp/core.c +++ b/drivers/opp/core.c @@ -2112,6 +2112,75 @@ static int _opp_set_availability(struct device *dev, unsigned long freq, return r; } +/** + * dev_pm_opp_adjust_voltage() - helper to change the voltage of an OPP + * @dev: device for which we do this operation + * @freq: OPP frequency to adjust voltage of + * @u_volt: new OPP target voltage + * @u_volt_min: new OPP min voltage + * @u_volt_max: new OPP max voltage + * + * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the + * copy operation, returns 0 if no modifcation was done OR modification was + * successful. + */ +int dev_pm_opp_adjust_voltage(struct device *dev, unsigned long freq, + unsigned long u_volt, unsigned long u_volt_min, + unsigned long u_volt_max) + +{ + struct opp_table *opp_table; + struct dev_pm_opp *tmp_opp, *opp = ERR_PTR(-ENODEV); + int r = 0; + + /* Find the opp_table */ + opp_table = _find_opp_table(dev); + if (IS_ERR(opp_table)) { + r = PTR_ERR(opp_table); + dev_warn(dev, "%s: Device OPP not found (%d)\n", __func__, r); + return r; + } + + mutex_lock(&opp_table->lock); + + /* Do we have the frequency? */ + list_for_each_entry(tmp_opp, &opp_table->opp_list, node) { + if (tmp_opp->rate == freq) { + opp = tmp_opp; + break; + } + } + + if (IS_ERR(opp)) { + r = PTR_ERR(opp); + goto adjust_unlock; + } + + /* Is update really needed? */ + if (opp->supplies->u_volt == u_volt) + goto adjust_unlock; + + opp->supplies->u_volt = u_volt; + opp->supplies->u_volt_min = u_volt_min; + opp->supplies->u_volt_max = u_volt_max; + + dev_pm_opp_get(opp); + mutex_unlock(&opp_table->lock); + + /* Notify the voltage change of the OPP */ + blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADJUST_VOLTAGE, + opp); + + dev_pm_opp_put(opp); + goto adjust_put_table; + +adjust_unlock: + mutex_unlock(&opp_table->lock); +adjust_put_table: + dev_pm_opp_put_opp_table(opp_table); + return r; +} + /** * dev_pm_opp_enable() - Enable a specific OPP * @dev: device for which we do this operation diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h index b8197ab014f2..747861816f4f 100644 --- a/include/linux/pm_opp.h +++ b/include/linux/pm_opp.h @@ -22,6 +22,7 @@ struct opp_table; enum dev_pm_opp_event { OPP_EVENT_ADD, OPP_EVENT_REMOVE, OPP_EVENT_ENABLE, OPP_EVENT_DISABLE, + OPP_EVENT_ADJUST_VOLTAGE, }; /** @@ -113,6 +114,10 @@ int dev_pm_opp_add(struct device *dev, unsigned long freq, void dev_pm_opp_remove(struct device *dev, unsigned long freq); void dev_pm_opp_remove_all_dynamic(struct device *dev); +int dev_pm_opp_adjust_voltage(struct device *dev, unsigned long freq, + unsigned long u_volt, unsigned long u_volt_min, + unsigned long u_volt_max); + int dev_pm_opp_enable(struct device *dev, unsigned long freq); int dev_pm_opp_disable(struct device *dev, unsigned long freq); @@ -242,6 +247,14 @@ static inline void dev_pm_opp_remove_all_dynamic(struct device *dev) { } +static inline int +dev_pm_opp_adjust_voltage(struct device *dev, unsigned long freq, + unsigned long u_volt, unsigned long u_volt_min, + unsigned long u_volt_max) +{ + return 0; +} + static inline int dev_pm_opp_enable(struct device *dev, unsigned long freq) { return 0;