| Message ID | 20190707223303.6755-3-digetx@gmail.com |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | More improvements for Tegra30 devfreq driver | expand |
On 19. 7. 8. 오전 7:32, Dmitry Osipenko wrote: > There is no real need to keep interrupt always-enabled, will be nicer > to keep it disabled while governor is inactive. > > Suggested-by: Thierry Reding <thierry.reding@gmail.com> > Signed-off-by: Dmitry Osipenko <digetx@gmail.com> > --- > drivers/devfreq/tegra30-devfreq.c | 43 ++++++++++++++++--------------- > 1 file changed, 22 insertions(+), 21 deletions(-) > > diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c > index a27300f40b0b..5e2b133babdd 100644 > --- a/drivers/devfreq/tegra30-devfreq.c > +++ b/drivers/devfreq/tegra30-devfreq.c > @@ -11,6 +11,7 @@ > #include <linux/devfreq.h> > #include <linux/interrupt.h> > #include <linux/io.h> > +#include <linux/irq.h> > #include <linux/module.h> > #include <linux/mod_devicetable.h> > #include <linux/platform_device.h> > @@ -416,8 +417,6 @@ static void tegra_actmon_start(struct tegra_devfreq *tegra) > { > unsigned int i; > > - disable_irq(tegra->irq); > - > actmon_writel(tegra, ACTMON_SAMPLING_PERIOD - 1, > ACTMON_GLB_PERIOD_CTRL); > > @@ -442,8 +441,6 @@ static void tegra_actmon_stop(struct tegra_devfreq *tegra) > } > > actmon_write_barrier(tegra); > - > - enable_irq(tegra->irq); > } > > static int tegra_devfreq_target(struct device *dev, unsigned long *freq, > @@ -552,6 +549,12 @@ static int tegra_governor_event_handler(struct devfreq *devfreq, > { > struct tegra_devfreq *tegra = dev_get_drvdata(devfreq->dev.parent); > > + /* > + * Couple device with the governor early as it is needed at > + * the moment of governor's start (used by ISR). > + */ > + tegra->devfreq = devfreq; I'm not sure it is necessary. Almost devfreq device get the devfreq instance on probe timing through devfreq_add_device directly. > + > switch (event) { > case DEVFREQ_GOV_START: > devfreq_monitor_start(devfreq); > @@ -586,10 +589,11 @@ static struct devfreq_governor tegra_devfreq_governor = { > > static int tegra_devfreq_probe(struct platform_device *pdev) > { > - struct tegra_devfreq *tegra; > struct tegra_devfreq_device *dev; > - unsigned int i; > + struct tegra_devfreq *tegra; > + struct devfreq *devfreq; > unsigned long rate; > + unsigned int i; > int err; > > tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL); > @@ -625,6 +629,16 @@ static int tegra_devfreq_probe(struct platform_device *pdev) > } > tegra->irq = err; > > + irq_set_status_flags(tegra->irq, IRQ_NOAUTOEN); > + > + err = devm_request_threaded_irq(&pdev->dev, tegra->irq, NULL, > + actmon_thread_isr, IRQF_ONESHOT, > + "tegra-devfreq", tegra); > + if (err) { > + dev_err(&pdev->dev, "Interrupt request failed: %d\n", err); > + return err; > + } > + > reset_control_assert(tegra->reset); > > err = clk_prepare_enable(tegra->clock); > @@ -672,28 +686,15 @@ static int tegra_devfreq_probe(struct platform_device *pdev) > } > > tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock); > - tegra->devfreq = devfreq_add_device(&pdev->dev, > - &tegra_devfreq_profile, > - "tegra_actmon", > - NULL); > + devfreq = devfreq_add_device(&pdev->dev, &tegra_devfreq_profile, > + "tegra_actmon", NULL); > if (IS_ERR(tegra->devfreq)) { Have to check 'devfreq' instead of 'tegra->devfreq'. Did you test it? It might be failed because 'tegra->devfreq is NULL. > err = PTR_ERR(tegra->devfreq); ditto. > goto remove_governor; > } > > - err = devm_request_threaded_irq(&pdev->dev, tegra->irq, NULL, > - actmon_thread_isr, IRQF_ONESHOT, > - "tegra-devfreq", tegra); > - if (err) { > - dev_err(&pdev->dev, "Interrupt request failed: %d\n", err); > - goto remove_devfreq; > - } > - > return 0; > > -remove_devfreq: > - devfreq_remove_device(tegra->devfreq); > - > remove_governor: > devfreq_remove_governor(&tegra_devfreq_governor); > >
16.07.2019 14:47, Chanwoo Choi пишет: > On 19. 7. 8. 오전 7:32, Dmitry Osipenko wrote: >> There is no real need to keep interrupt always-enabled, will be nicer >> to keep it disabled while governor is inactive. >> >> Suggested-by: Thierry Reding <thierry.reding@gmail.com> >> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> >> --- >> drivers/devfreq/tegra30-devfreq.c | 43 ++++++++++++++++--------------- >> 1 file changed, 22 insertions(+), 21 deletions(-) >> >> diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c >> index a27300f40b0b..5e2b133babdd 100644 >> --- a/drivers/devfreq/tegra30-devfreq.c >> +++ b/drivers/devfreq/tegra30-devfreq.c >> @@ -11,6 +11,7 @@ >> #include <linux/devfreq.h> >> #include <linux/interrupt.h> >> #include <linux/io.h> >> +#include <linux/irq.h> >> #include <linux/module.h> >> #include <linux/mod_devicetable.h> >> #include <linux/platform_device.h> >> @@ -416,8 +417,6 @@ static void tegra_actmon_start(struct tegra_devfreq *tegra) >> { >> unsigned int i; >> >> - disable_irq(tegra->irq); >> - >> actmon_writel(tegra, ACTMON_SAMPLING_PERIOD - 1, >> ACTMON_GLB_PERIOD_CTRL); >> >> @@ -442,8 +441,6 @@ static void tegra_actmon_stop(struct tegra_devfreq *tegra) >> } >> >> actmon_write_barrier(tegra); >> - >> - enable_irq(tegra->irq); >> } >> >> static int tegra_devfreq_target(struct device *dev, unsigned long *freq, >> @@ -552,6 +549,12 @@ static int tegra_governor_event_handler(struct devfreq *devfreq, >> { >> struct tegra_devfreq *tegra = dev_get_drvdata(devfreq->dev.parent); >> >> + /* >> + * Couple device with the governor early as it is needed at >> + * the moment of governor's start (used by ISR). >> + */ >> + tegra->devfreq = devfreq; > > I'm not sure it is necessary. Almost devfreq device get > the devfreq instance on probe timing through devfreq_add_device directly. This is necessary because this assignment is for the "governor" and not the "device". Governor is started during of devfreq_add_device(), hence there is no better way to assign device to the driver's governor. >> + >> switch (event) { >> case DEVFREQ_GOV_START: >> devfreq_monitor_start(devfreq); >> @@ -586,10 +589,11 @@ static struct devfreq_governor tegra_devfreq_governor = { >> >> static int tegra_devfreq_probe(struct platform_device *pdev) >> { >> - struct tegra_devfreq *tegra; >> struct tegra_devfreq_device *dev; >> - unsigned int i; >> + struct tegra_devfreq *tegra; >> + struct devfreq *devfreq; >> unsigned long rate; >> + unsigned int i; >> int err; >> >> tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL); >> @@ -625,6 +629,16 @@ static int tegra_devfreq_probe(struct platform_device *pdev) >> } >> tegra->irq = err; >> >> + irq_set_status_flags(tegra->irq, IRQ_NOAUTOEN); >> + >> + err = devm_request_threaded_irq(&pdev->dev, tegra->irq, NULL, >> + actmon_thread_isr, IRQF_ONESHOT, >> + "tegra-devfreq", tegra); >> + if (err) { >> + dev_err(&pdev->dev, "Interrupt request failed: %d\n", err); >> + return err; >> + } >> + >> reset_control_assert(tegra->reset); >> >> err = clk_prepare_enable(tegra->clock); >> @@ -672,28 +686,15 @@ static int tegra_devfreq_probe(struct platform_device *pdev) >> } >> >> tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock); >> - tegra->devfreq = devfreq_add_device(&pdev->dev, >> - &tegra_devfreq_profile, >> - "tegra_actmon", >> - NULL); >> + devfreq = devfreq_add_device(&pdev->dev, &tegra_devfreq_profile, >> + "tegra_actmon", NULL); >> if (IS_ERR(tegra->devfreq)) { > > Have to check 'devfreq' instead of 'tegra->devfreq'. > Did you test it? It might be failed because 'tegra->devfreq is NULL. That's a good catch! Thank you very much. >> err = PTR_ERR(tegra->devfreq); > > ditto. Ok
On 19. 7. 16. 오후 10:03, Dmitry Osipenko wrote: > 16.07.2019 14:47, Chanwoo Choi пишет: >> On 19. 7. 8. 오전 7:32, Dmitry Osipenko wrote: >>> There is no real need to keep interrupt always-enabled, will be nicer >>> to keep it disabled while governor is inactive. >>> >>> Suggested-by: Thierry Reding <thierry.reding@gmail.com> >>> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> >>> --- >>> drivers/devfreq/tegra30-devfreq.c | 43 ++++++++++++++++--------------- >>> 1 file changed, 22 insertions(+), 21 deletions(-) >>> >>> diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c >>> index a27300f40b0b..5e2b133babdd 100644 >>> --- a/drivers/devfreq/tegra30-devfreq.c >>> +++ b/drivers/devfreq/tegra30-devfreq.c >>> @@ -11,6 +11,7 @@ >>> #include <linux/devfreq.h> >>> #include <linux/interrupt.h> >>> #include <linux/io.h> >>> +#include <linux/irq.h> >>> #include <linux/module.h> >>> #include <linux/mod_devicetable.h> >>> #include <linux/platform_device.h> >>> @@ -416,8 +417,6 @@ static void tegra_actmon_start(struct tegra_devfreq *tegra) >>> { >>> unsigned int i; >>> >>> - disable_irq(tegra->irq); >>> - >>> actmon_writel(tegra, ACTMON_SAMPLING_PERIOD - 1, >>> ACTMON_GLB_PERIOD_CTRL); >>> >>> @@ -442,8 +441,6 @@ static void tegra_actmon_stop(struct tegra_devfreq *tegra) >>> } >>> >>> actmon_write_barrier(tegra); >>> - >>> - enable_irq(tegra->irq); >>> } >>> >>> static int tegra_devfreq_target(struct device *dev, unsigned long *freq, >>> @@ -552,6 +549,12 @@ static int tegra_governor_event_handler(struct devfreq *devfreq, >>> { >>> struct tegra_devfreq *tegra = dev_get_drvdata(devfreq->dev.parent); >>> >>> + /* >>> + * Couple device with the governor early as it is needed at >>> + * the moment of governor's start (used by ISR). >>> + */ >>> + tegra->devfreq = devfreq; >> >> I'm not sure it is necessary. Almost devfreq device get >> the devfreq instance on probe timing through devfreq_add_device directly. > > This is necessary because this assignment is for the "governor" and not > the "device". Governor is started during of devfreq_add_device(), hence > there is no better way to assign device to the driver's governor. OK. I understand. But, I have a question. Is it working before this patch? How can you test it on that tegra->devfreq is NULL? > >>> + >>> switch (event) { >>> case DEVFREQ_GOV_START: >>> devfreq_monitor_start(devfreq); >>> @@ -586,10 +589,11 @@ static struct devfreq_governor tegra_devfreq_governor = { >>> >>> static int tegra_devfreq_probe(struct platform_device *pdev) >>> { >>> - struct tegra_devfreq *tegra; >>> struct tegra_devfreq_device *dev; >>> - unsigned int i; >>> + struct tegra_devfreq *tegra; >>> + struct devfreq *devfreq; >>> unsigned long rate; >>> + unsigned int i; >>> int err; >>> >>> tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL); >>> @@ -625,6 +629,16 @@ static int tegra_devfreq_probe(struct platform_device *pdev) >>> } >>> tegra->irq = err; >>> >>> + irq_set_status_flags(tegra->irq, IRQ_NOAUTOEN); >>> + >>> + err = devm_request_threaded_irq(&pdev->dev, tegra->irq, NULL, >>> + actmon_thread_isr, IRQF_ONESHOT, >>> + "tegra-devfreq", tegra); >>> + if (err) { >>> + dev_err(&pdev->dev, "Interrupt request failed: %d\n", err); >>> + return err; >>> + } >>> + >>> reset_control_assert(tegra->reset); >>> >>> err = clk_prepare_enable(tegra->clock); >>> @@ -672,28 +686,15 @@ static int tegra_devfreq_probe(struct platform_device *pdev) >>> } >>> >>> tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock); >>> - tegra->devfreq = devfreq_add_device(&pdev->dev, >>> - &tegra_devfreq_profile, >>> - "tegra_actmon", >>> - NULL); >>> + devfreq = devfreq_add_device(&pdev->dev, &tegra_devfreq_profile, >>> + "tegra_actmon", NULL); >>> if (IS_ERR(tegra->devfreq)) { >> >> Have to check 'devfreq' instead of 'tegra->devfreq'. >> Did you test it? It might be failed because 'tegra->devfreq is NULL. > > That's a good catch! Thank you very much. > >>> err = PTR_ERR(tegra->devfreq); >> >> ditto. > > Ok > >
17.07.2019 9:37, Chanwoo Choi пишет: > On 19. 7. 16. 오후 10:03, Dmitry Osipenko wrote: >> 16.07.2019 14:47, Chanwoo Choi пишет: >>> On 19. 7. 8. 오전 7:32, Dmitry Osipenko wrote: >>>> There is no real need to keep interrupt always-enabled, will be nicer >>>> to keep it disabled while governor is inactive. >>>> >>>> Suggested-by: Thierry Reding <thierry.reding@gmail.com> >>>> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> >>>> --- >>>> drivers/devfreq/tegra30-devfreq.c | 43 ++++++++++++++++--------------- >>>> 1 file changed, 22 insertions(+), 21 deletions(-) >>>> >>>> diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c >>>> index a27300f40b0b..5e2b133babdd 100644 >>>> --- a/drivers/devfreq/tegra30-devfreq.c >>>> +++ b/drivers/devfreq/tegra30-devfreq.c >>>> @@ -11,6 +11,7 @@ >>>> #include <linux/devfreq.h> >>>> #include <linux/interrupt.h> >>>> #include <linux/io.h> >>>> +#include <linux/irq.h> >>>> #include <linux/module.h> >>>> #include <linux/mod_devicetable.h> >>>> #include <linux/platform_device.h> >>>> @@ -416,8 +417,6 @@ static void tegra_actmon_start(struct tegra_devfreq *tegra) >>>> { >>>> unsigned int i; >>>> >>>> - disable_irq(tegra->irq); >>>> - >>>> actmon_writel(tegra, ACTMON_SAMPLING_PERIOD - 1, >>>> ACTMON_GLB_PERIOD_CTRL); >>>> >>>> @@ -442,8 +441,6 @@ static void tegra_actmon_stop(struct tegra_devfreq *tegra) >>>> } >>>> >>>> actmon_write_barrier(tegra); >>>> - >>>> - enable_irq(tegra->irq); >>>> } >>>> >>>> static int tegra_devfreq_target(struct device *dev, unsigned long *freq, >>>> @@ -552,6 +549,12 @@ static int tegra_governor_event_handler(struct devfreq *devfreq, >>>> { >>>> struct tegra_devfreq *tegra = dev_get_drvdata(devfreq->dev.parent); >>>> >>>> + /* >>>> + * Couple device with the governor early as it is needed at >>>> + * the moment of governor's start (used by ISR). >>>> + */ >>>> + tegra->devfreq = devfreq; >>> >>> I'm not sure it is necessary. Almost devfreq device get >>> the devfreq instance on probe timing through devfreq_add_device directly. >> >> This is necessary because this assignment is for the "governor" and not >> the "device". Governor is started during of devfreq_add_device(), hence >> there is no better way to assign device to the driver's governor. > > OK. I understand. > > But, I have a question. Is it working before this patch? > How can you test it on that tegra->devfreq is NULL? It was working before this patch because previously interrupt was requested *after* devfreq_add_device(), now the IRQ requesting happens *before* devfreq_add_device() and enabling *during of*. If interrupt fires before the assignment happened, then ISR gets a NULL deference and this is easily reproducible. Please note that 'tegra->devfreq' is used only by the ISR and onward, in the further patches of this series the usage is extended by the cpufreq notifier. >> >>>> + >>>> switch (event) { >>>> case DEVFREQ_GOV_START: >>>> devfreq_monitor_start(devfreq); >>>> @@ -586,10 +589,11 @@ static struct devfreq_governor tegra_devfreq_governor = { >>>> >>>> static int tegra_devfreq_probe(struct platform_device *pdev) >>>> { >>>> - struct tegra_devfreq *tegra; >>>> struct tegra_devfreq_device *dev; >>>> - unsigned int i; >>>> + struct tegra_devfreq *tegra; >>>> + struct devfreq *devfreq; >>>> unsigned long rate; >>>> + unsigned int i; >>>> int err; >>>> >>>> tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL); >>>> @@ -625,6 +629,16 @@ static int tegra_devfreq_probe(struct platform_device *pdev) >>>> } >>>> tegra->irq = err; >>>> >>>> + irq_set_status_flags(tegra->irq, IRQ_NOAUTOEN); >>>> + >>>> + err = devm_request_threaded_irq(&pdev->dev, tegra->irq, NULL, >>>> + actmon_thread_isr, IRQF_ONESHOT, >>>> + "tegra-devfreq", tegra); >>>> + if (err) { >>>> + dev_err(&pdev->dev, "Interrupt request failed: %d\n", err); >>>> + return err; >>>> + } >>>> + >>>> reset_control_assert(tegra->reset); >>>> >>>> err = clk_prepare_enable(tegra->clock); >>>> @@ -672,28 +686,15 @@ static int tegra_devfreq_probe(struct platform_device *pdev) >>>> } >>>> >>>> tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock); >>>> - tegra->devfreq = devfreq_add_device(&pdev->dev, >>>> - &tegra_devfreq_profile, >>>> - "tegra_actmon", >>>> - NULL); >>>> + devfreq = devfreq_add_device(&pdev->dev, &tegra_devfreq_profile, >>>> + "tegra_actmon", NULL); >>>> if (IS_ERR(tegra->devfreq)) { >>> >>> Have to check 'devfreq' instead of 'tegra->devfreq'. >>> Did you test it? It might be failed because 'tegra->devfreq is NULL. >> >> That's a good catch! Thank you very much. >> >>>> err = PTR_ERR(tegra->devfreq); >>> >>> ditto. >> >> Ok
diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c index a27300f40b0b..5e2b133babdd 100644 --- a/drivers/devfreq/tegra30-devfreq.c +++ b/drivers/devfreq/tegra30-devfreq.c @@ -11,6 +11,7 @@ #include <linux/devfreq.h> #include <linux/interrupt.h> #include <linux/io.h> +#include <linux/irq.h> #include <linux/module.h> #include <linux/mod_devicetable.h> #include <linux/platform_device.h> @@ -416,8 +417,6 @@ static void tegra_actmon_start(struct tegra_devfreq *tegra) { unsigned int i; - disable_irq(tegra->irq); - actmon_writel(tegra, ACTMON_SAMPLING_PERIOD - 1, ACTMON_GLB_PERIOD_CTRL); @@ -442,8 +441,6 @@ static void tegra_actmon_stop(struct tegra_devfreq *tegra) } actmon_write_barrier(tegra); - - enable_irq(tegra->irq); } static int tegra_devfreq_target(struct device *dev, unsigned long *freq, @@ -552,6 +549,12 @@ static int tegra_governor_event_handler(struct devfreq *devfreq, { struct tegra_devfreq *tegra = dev_get_drvdata(devfreq->dev.parent); + /* + * Couple device with the governor early as it is needed at + * the moment of governor's start (used by ISR). + */ + tegra->devfreq = devfreq; + switch (event) { case DEVFREQ_GOV_START: devfreq_monitor_start(devfreq); @@ -586,10 +589,11 @@ static struct devfreq_governor tegra_devfreq_governor = { static int tegra_devfreq_probe(struct platform_device *pdev) { - struct tegra_devfreq *tegra; struct tegra_devfreq_device *dev; - unsigned int i; + struct tegra_devfreq *tegra; + struct devfreq *devfreq; unsigned long rate; + unsigned int i; int err; tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL); @@ -625,6 +629,16 @@ static int tegra_devfreq_probe(struct platform_device *pdev) } tegra->irq = err; + irq_set_status_flags(tegra->irq, IRQ_NOAUTOEN); + + err = devm_request_threaded_irq(&pdev->dev, tegra->irq, NULL, + actmon_thread_isr, IRQF_ONESHOT, + "tegra-devfreq", tegra); + if (err) { + dev_err(&pdev->dev, "Interrupt request failed: %d\n", err); + return err; + } + reset_control_assert(tegra->reset); err = clk_prepare_enable(tegra->clock); @@ -672,28 +686,15 @@ static int tegra_devfreq_probe(struct platform_device *pdev) } tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock); - tegra->devfreq = devfreq_add_device(&pdev->dev, - &tegra_devfreq_profile, - "tegra_actmon", - NULL); + devfreq = devfreq_add_device(&pdev->dev, &tegra_devfreq_profile, + "tegra_actmon", NULL); if (IS_ERR(tegra->devfreq)) { err = PTR_ERR(tegra->devfreq); goto remove_governor; } - err = devm_request_threaded_irq(&pdev->dev, tegra->irq, NULL, - actmon_thread_isr, IRQF_ONESHOT, - "tegra-devfreq", tegra); - if (err) { - dev_err(&pdev->dev, "Interrupt request failed: %d\n", err); - goto remove_devfreq; - } - return 0; -remove_devfreq: - devfreq_remove_device(tegra->devfreq); - remove_governor: devfreq_remove_governor(&tegra_devfreq_governor);
There is no real need to keep interrupt always-enabled, will be nicer to keep it disabled while governor is inactive. Suggested-by: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> --- drivers/devfreq/tegra30-devfreq.c | 43 ++++++++++++++++--------------- 1 file changed, 22 insertions(+), 21 deletions(-)