| Message ID | 20201025221735.3062-52-digetx@gmail.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | Introduce memory interconnect for NVIDIA Tegra SoCs | expand |
Hi Dmitry, On Mon, Oct 26, 2020 at 7:22 AM Dmitry Osipenko <digetx@gmail.com> wrote: > > This patch moves ACTMON driver away from generating OPP table by itself, > transitioning it to use the table which comes from device-tree. This > change breaks compatibility with older device-trees in order to bring > support for the interconnect framework to the driver. This is a mandatory > change which needs to be done in order to implement interconnect-based > memory DVFS. Users of legacy device-trees will get a message telling that > theirs DT needs to be upgraded. Now ACTMON issues memory bandwidth request > using dev_pm_opp_set_bw(), instead of driving EMC clock rate directly. > > Tested-by: Peter Geis <pgwipeout@gmail.com> > Tested-by: Nicolas Chauvet <kwizart@gmail.com> > Signed-off-by: Dmitry Osipenko <digetx@gmail.com> > --- > drivers/devfreq/tegra30-devfreq.c | 91 ++++++++++++++++--------------- > 1 file changed, 48 insertions(+), 43 deletions(-) > > diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c > index 3f732ab53573..1b0b91a71886 100644 > --- a/drivers/devfreq/tegra30-devfreq.c > +++ b/drivers/devfreq/tegra30-devfreq.c > @@ -19,6 +19,8 @@ > #include <linux/reset.h> > #include <linux/workqueue.h> > > +#include <soc/tegra/fuse.h> > + > #include "governor.h" > > #define ACTMON_GLB_STATUS 0x0 > @@ -155,6 +157,7 @@ struct tegra_devfreq_device { > > struct tegra_devfreq { > struct devfreq *devfreq; > + struct opp_table *opp_table; > > struct reset_control *reset; > struct clk *clock; > @@ -612,34 +615,19 @@ static void tegra_actmon_stop(struct tegra_devfreq *tegra) > static int tegra_devfreq_target(struct device *dev, unsigned long *freq, > u32 flags) > { > - struct tegra_devfreq *tegra = dev_get_drvdata(dev); > - struct devfreq *devfreq = tegra->devfreq; > struct dev_pm_opp *opp; > - unsigned long rate; > - int err; > + int ret; > > opp = devfreq_recommended_opp(dev, freq, flags); > if (IS_ERR(opp)) { > - dev_err(dev, "Failed to find opp for %lu Hz\n", *freq); > + dev_err(dev, "failed to find opp for %lu Hz\n", *freq); > return PTR_ERR(opp); > } > - rate = dev_pm_opp_get_freq(opp); > - dev_pm_opp_put(opp); > - > - err = clk_set_min_rate(tegra->emc_clock, rate * KHZ); > - if (err) > - return err; > - > - err = clk_set_rate(tegra->emc_clock, 0); > - if (err) > - goto restore_min_rate; > > - return 0; > - > -restore_min_rate: > - clk_set_min_rate(tegra->emc_clock, devfreq->previous_freq); > + ret = dev_pm_opp_set_bw(dev, opp); > + dev_pm_opp_put(opp); > > - return err; > + return ret; > } > > static int tegra_devfreq_get_dev_status(struct device *dev, > @@ -655,7 +643,7 @@ static int tegra_devfreq_get_dev_status(struct device *dev, > stat->private_data = tegra; > > /* The below are to be used by the other governors */ > - stat->current_frequency = cur_freq; > + stat->current_frequency = cur_freq * KHZ; I can't find any change related to the frequency unit on this patch. Do you fix the previous bug of the frequency unit? > > actmon_dev = &tegra->devices[MCALL]; > > @@ -705,7 +693,7 @@ static int tegra_governor_get_target(struct devfreq *devfreq, > target_freq = max(target_freq, dev->target_freq); > } > > - *freq = target_freq; > + *freq = target_freq * KHZ; ditto. > > return 0; > } > @@ -773,13 +761,22 @@ static struct devfreq_governor tegra_devfreq_governor = { > > static int tegra_devfreq_probe(struct platform_device *pdev) > { > + u32 hw_version = BIT(tegra_sku_info.soc_speedo_id); > struct tegra_devfreq_device *dev; > struct tegra_devfreq *tegra; > + struct opp_table *opp_table; > struct devfreq *devfreq; > unsigned int i; > long rate; > int err; > > + /* legacy device-trees don't have OPP table and must be updated */ > + if (!device_property_present(&pdev->dev, "operating-points-v2")) { > + dev_err(&pdev->dev, "OPP table not found, cannot continue\n"); > + dev_err(&pdev->dev, "please update your device tree\n"); > + return -ENODEV; > + } As you mentioned, it breaks the old dtb. I have no objection to improving the driver. Instead, you need confirmation from the Devicetree maintainer. And, I recommend that you use dev_pm_opp_of_get_opp_desc_node(&pdev->dev) to check whether a device contains opp-table or not. > + > tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL); > if (!tegra) > return -ENOMEM; > @@ -821,11 +818,29 @@ static int tegra_devfreq_probe(struct platform_device *pdev) > return err; > } > > + tegra->opp_table = dev_pm_opp_get_opp_table(&pdev->dev); > + if (IS_ERR(tegra->opp_table)) > + return dev_err_probe(&pdev->dev, PTR_ERR(tegra->opp_table), > + "Failed to prepare OPP table\n"); As I knew, each device can contain the opp_table on devicetree. It means that opp_table has not depended to another device driver. Did you see this exception case with EPROBE_DEFER error? > + > + opp_table = dev_pm_opp_set_supported_hw(&pdev->dev, &hw_version, 1); > + err = PTR_ERR_OR_ZERO(opp_table); > + if (err) { > + dev_err(&pdev->dev, "Failed to set supported HW: %d\n", err); > + goto put_table; > + } > + > + err = dev_pm_opp_of_add_table(&pdev->dev); > + if (err) { > + dev_err(&pdev->dev, "Failed to add OPP table: %d\n", err); > + goto put_hw; > + } > + > err = clk_prepare_enable(tegra->clock); > if (err) { > dev_err(&pdev->dev, > "Failed to prepare and enable ACTMON clock\n"); > - return err; > + goto remove_table; > } > > err = reset_control_reset(tegra->reset); > @@ -849,23 +864,6 @@ static int tegra_devfreq_probe(struct platform_device *pdev) > dev->regs = tegra->regs + dev->config->offset; > } > > - for (rate = 0; rate <= tegra->max_freq * KHZ; rate++) { > - rate = clk_round_rate(tegra->emc_clock, rate); > - > - if (rate < 0) { > - dev_err(&pdev->dev, > - "Failed to round clock rate: %ld\n", rate); > - err = rate; > - goto remove_opps; > - } > - > - err = dev_pm_opp_add(&pdev->dev, rate / KHZ, 0); > - if (err) { > - dev_err(&pdev->dev, "Failed to add OPP: %d\n", err); > - goto remove_opps; > - } > - } > - > platform_set_drvdata(pdev, tegra); > > tegra->clk_rate_change_nb.notifier_call = tegra_actmon_clk_notify_cb; > @@ -881,7 +879,6 @@ static int tegra_devfreq_probe(struct platform_device *pdev) > } > > tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock); > - tegra_devfreq_profile.initial_freq /= KHZ; > > devfreq = devfreq_add_device(&pdev->dev, &tegra_devfreq_profile, > "tegra_actmon", NULL); > @@ -901,6 +898,12 @@ static int tegra_devfreq_probe(struct platform_device *pdev) > reset_control_reset(tegra->reset); > disable_clk: > clk_disable_unprepare(tegra->clock); > +remove_table: > + dev_pm_opp_of_remove_table(&pdev->dev); > +put_hw: > + dev_pm_opp_put_supported_hw(tegra->opp_table); > +put_table: > + dev_pm_opp_put_opp_table(tegra->opp_table); > > return err; > } > @@ -912,11 +915,13 @@ static int tegra_devfreq_remove(struct platform_device *pdev) > devfreq_remove_device(tegra->devfreq); > devfreq_remove_governor(&tegra_devfreq_governor); > > - dev_pm_opp_remove_all_dynamic(&pdev->dev); > - > reset_control_reset(tegra->reset); > clk_disable_unprepare(tegra->clock); > > + dev_pm_opp_of_remove_table(&pdev->dev); > + dev_pm_opp_put_supported_hw(tegra->opp_table); > + dev_pm_opp_put_opp_table(tegra->opp_table); > + > return 0; > } > > -- > 2.27.0 >
Hi Dmitry, On Mon, Oct 26, 2020 at 7:22 AM Dmitry Osipenko <digetx@gmail.com> wrote: > > This patch moves ACTMON driver away from generating OPP table by itself, > transitioning it to use the table which comes from device-tree. This > change breaks compatibility with older device-trees in order to bring > support for the interconnect framework to the driver. This is a mandatory > change which needs to be done in order to implement interconnect-based > memory DVFS. Users of legacy device-trees will get a message telling that > theirs DT needs to be upgraded. Now ACTMON issues memory bandwidth request > using dev_pm_opp_set_bw(), instead of driving EMC clock rate directly. > > Tested-by: Peter Geis <pgwipeout@gmail.com> > Tested-by: Nicolas Chauvet <kwizart@gmail.com> > Signed-off-by: Dmitry Osipenko <digetx@gmail.com> > --- > drivers/devfreq/tegra30-devfreq.c | 91 ++++++++++++++++--------------- > 1 file changed, 48 insertions(+), 43 deletions(-) > > diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c > index 3f732ab53573..1b0b91a71886 100644 > --- a/drivers/devfreq/tegra30-devfreq.c > +++ b/drivers/devfreq/tegra30-devfreq.c > @@ -19,6 +19,8 @@ > #include <linux/reset.h> > #include <linux/workqueue.h> > > +#include <soc/tegra/fuse.h> > + This patch touches the OPP. Is it related to this change? > #include "governor.h" > > #define ACTMON_GLB_STATUS 0x0 > @@ -155,6 +157,7 @@ struct tegra_devfreq_device { > > struct tegra_devfreq { > struct devfreq *devfreq; > + struct opp_table *opp_table; > > struct reset_control *reset; > struct clk *clock; > @@ -612,34 +615,19 @@ static void tegra_actmon_stop(struct tegra_devfreq *tegra) > static int tegra_devfreq_target(struct device *dev, unsigned long *freq, > u32 flags) > { > - struct tegra_devfreq *tegra = dev_get_drvdata(dev); > - struct devfreq *devfreq = tegra->devfreq; > struct dev_pm_opp *opp; > - unsigned long rate; > - int err; > + int ret; > > opp = devfreq_recommended_opp(dev, freq, flags); > if (IS_ERR(opp)) { > - dev_err(dev, "Failed to find opp for %lu Hz\n", *freq); > + dev_err(dev, "failed to find opp for %lu Hz\n", *freq); You used the 'Failed to' format in almost every error case. Don't need to change it. (snip) Best Regards, Chanwoo Choi
01.11.2020 17:39, Chanwoo Choi пишет: > Hi Dmitry, > > On Mon, Oct 26, 2020 at 7:22 AM Dmitry Osipenko <digetx@gmail.com> wrote: >> >> This patch moves ACTMON driver away from generating OPP table by itself, >> transitioning it to use the table which comes from device-tree. This >> change breaks compatibility with older device-trees in order to bring >> support for the interconnect framework to the driver. This is a mandatory >> change which needs to be done in order to implement interconnect-based >> memory DVFS. Users of legacy device-trees will get a message telling that >> theirs DT needs to be upgraded. Now ACTMON issues memory bandwidth request >> using dev_pm_opp_set_bw(), instead of driving EMC clock rate directly. >> >> Tested-by: Peter Geis <pgwipeout@gmail.com> >> Tested-by: Nicolas Chauvet <kwizart@gmail.com> >> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> >> --- ... >> static int tegra_devfreq_get_dev_status(struct device *dev, >> @@ -655,7 +643,7 @@ static int tegra_devfreq_get_dev_status(struct device *dev, >> stat->private_data = tegra; >> >> /* The below are to be used by the other governors */ >> - stat->current_frequency = cur_freq; >> + stat->current_frequency = cur_freq * KHZ; > > I can't find any change related to the frequency unit on this patch. > Do you fix the previous bug of the frequency unit? Previously, OPP entries that were generated by the driver used KHz units. Now, OPP entries are coming from a device-tree and they have Hz units. This driver operates with KHz internally, hence we need to convert the units now. >> >> actmon_dev = &tegra->devices[MCALL]; >> >> @@ -705,7 +693,7 @@ static int tegra_governor_get_target(struct devfreq *devfreq, >> target_freq = max(target_freq, dev->target_freq); >> } >> >> - *freq = target_freq; >> + *freq = target_freq * KHZ; > > ditto. > >> >> return 0; >> } >> @@ -773,13 +761,22 @@ static struct devfreq_governor tegra_devfreq_governor = { >> >> static int tegra_devfreq_probe(struct platform_device *pdev) >> { >> + u32 hw_version = BIT(tegra_sku_info.soc_speedo_id); >> struct tegra_devfreq_device *dev; >> struct tegra_devfreq *tegra; >> + struct opp_table *opp_table; >> struct devfreq *devfreq; >> unsigned int i; >> long rate; >> int err; >> >> + /* legacy device-trees don't have OPP table and must be updated */ >> + if (!device_property_present(&pdev->dev, "operating-points-v2")) { >> + dev_err(&pdev->dev, "OPP table not found, cannot continue\n"); >> + dev_err(&pdev->dev, "please update your device tree\n"); >> + return -ENODEV; >> + } > > As you mentioned, it breaks the old dtb. I have no objection to improving > the driver. Instead, you need confirmation from the Devicetree maintainer. Older DTBs will continue to work, but devfreq driver won't. We already did this for other Tegra drivers before (CPUFREQ driver for example) and Rob Herring confirmed that there is no problem here. > And, > I recommend that you use dev_pm_opp_of_get_opp_desc_node(&pdev->dev) > to check whether a device contains opp-table or not. I'm not sure what are the benefits, this will make code less expressive/readable and we will need to add extra of_node_put(), which device_property_present() handles for us. Could you please give the rationale? >> + >> tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL); >> if (!tegra) >> return -ENOMEM; >> @@ -821,11 +818,29 @@ static int tegra_devfreq_probe(struct platform_device *pdev) >> return err; >> } >> >> + tegra->opp_table = dev_pm_opp_get_opp_table(&pdev->dev); >> + if (IS_ERR(tegra->opp_table)) >> + return dev_err_probe(&pdev->dev, PTR_ERR(tegra->opp_table), >> + "Failed to prepare OPP table\n"); > > As I knew, each device can contain the opp_table on devicetree. > It means that opp_table has not depended to another device driver. > Did you see this exception case with EPROBE_DEFER error? OPP core will try to grab the clock reference for the table and it may cause EPROBE_DEFER. Although, it shouldn't happen here because we have devm_clk_get() before the get_opp_table(), hence seems the deferred probe indeed shouldn't happen in this case.
01.11.2020 17:44, Chanwoo Choi пишет: > Hi Dmitry, > > On Mon, Oct 26, 2020 at 7:22 AM Dmitry Osipenko <digetx@gmail.com> wrote: >> >> This patch moves ACTMON driver away from generating OPP table by itself, >> transitioning it to use the table which comes from device-tree. This >> change breaks compatibility with older device-trees in order to bring >> support for the interconnect framework to the driver. This is a mandatory >> change which needs to be done in order to implement interconnect-based >> memory DVFS. Users of legacy device-trees will get a message telling that >> theirs DT needs to be upgraded. Now ACTMON issues memory bandwidth request >> using dev_pm_opp_set_bw(), instead of driving EMC clock rate directly. >> >> Tested-by: Peter Geis <pgwipeout@gmail.com> >> Tested-by: Nicolas Chauvet <kwizart@gmail.com> >> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> >> --- >> drivers/devfreq/tegra30-devfreq.c | 91 ++++++++++++++++--------------- >> 1 file changed, 48 insertions(+), 43 deletions(-) >> >> diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c >> index 3f732ab53573..1b0b91a71886 100644 >> --- a/drivers/devfreq/tegra30-devfreq.c >> +++ b/drivers/devfreq/tegra30-devfreq.c >> @@ -19,6 +19,8 @@ >> #include <linux/reset.h> >> #include <linux/workqueue.h> >> >> +#include <soc/tegra/fuse.h> >> + > > This patch touches the OPP. Is it related to this change? Yes, this is needed for the dev_pm_opp_set_supported_hw(). >> #include "governor.h" >> >> #define ACTMON_GLB_STATUS 0x0 >> @@ -155,6 +157,7 @@ struct tegra_devfreq_device { >> >> struct tegra_devfreq { >> struct devfreq *devfreq; >> + struct opp_table *opp_table; >> >> struct reset_control *reset; >> struct clk *clock; >> @@ -612,34 +615,19 @@ static void tegra_actmon_stop(struct tegra_devfreq *tegra) >> static int tegra_devfreq_target(struct device *dev, unsigned long *freq, >> u32 flags) >> { >> - struct tegra_devfreq *tegra = dev_get_drvdata(dev); >> - struct devfreq *devfreq = tegra->devfreq; >> struct dev_pm_opp *opp; >> - unsigned long rate; >> - int err; >> + int ret; >> >> opp = devfreq_recommended_opp(dev, freq, flags); >> if (IS_ERR(opp)) { >> - dev_err(dev, "Failed to find opp for %lu Hz\n", *freq); >> + dev_err(dev, "failed to find opp for %lu Hz\n", *freq); > > You used the 'Failed to' format in almost every error case. > Don't need to change it. > (snip) Good catch, thanks.
Hi Dmitry, On Mon, Nov 2, 2020 at 12:23 AM Dmitry Osipenko <digetx@gmail.com> wrote: > > 01.11.2020 17:39, Chanwoo Choi пишет: > > Hi Dmitry, > > > > On Mon, Oct 26, 2020 at 7:22 AM Dmitry Osipenko <digetx@gmail.com> wrote: > >> > >> This patch moves ACTMON driver away from generating OPP table by itself, > >> transitioning it to use the table which comes from device-tree. This > >> change breaks compatibility with older device-trees in order to bring > >> support for the interconnect framework to the driver. This is a mandatory > >> change which needs to be done in order to implement interconnect-based > >> memory DVFS. Users of legacy device-trees will get a message telling that > >> theirs DT needs to be upgraded. Now ACTMON issues memory bandwidth request > >> using dev_pm_opp_set_bw(), instead of driving EMC clock rate directly. > >> > >> Tested-by: Peter Geis <pgwipeout@gmail.com> > >> Tested-by: Nicolas Chauvet <kwizart@gmail.com> > >> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> > >> --- > ... > >> static int tegra_devfreq_get_dev_status(struct device *dev, > >> @@ -655,7 +643,7 @@ static int tegra_devfreq_get_dev_status(struct device *dev, > >> stat->private_data = tegra; > >> > >> /* The below are to be used by the other governors */ > >> - stat->current_frequency = cur_freq; > >> + stat->current_frequency = cur_freq * KHZ; > > > > I can't find any change related to the frequency unit on this patch. > > Do you fix the previous bug of the frequency unit? > > Previously, OPP entries that were generated by the driver used KHz > units. Now, OPP entries are coming from a device-tree and they have Hz > units. This driver operates with KHz internally, hence we need to > convert the units now. OK. Thanks. > > >> > >> actmon_dev = &tegra->devices[MCALL]; > >> > >> @@ -705,7 +693,7 @@ static int tegra_governor_get_target(struct devfreq *devfreq, > >> target_freq = max(target_freq, dev->target_freq); > >> } > >> > >> - *freq = target_freq; > >> + *freq = target_freq * KHZ; > > > > ditto. > > > >> > >> return 0; > >> } > >> @@ -773,13 +761,22 @@ static struct devfreq_governor tegra_devfreq_governor = { > >> > >> static int tegra_devfreq_probe(struct platform_device *pdev) > >> { > >> + u32 hw_version = BIT(tegra_sku_info.soc_speedo_id); > >> struct tegra_devfreq_device *dev; > >> struct tegra_devfreq *tegra; > >> + struct opp_table *opp_table; > >> struct devfreq *devfreq; > >> unsigned int i; > >> long rate; > >> int err; > >> > >> + /* legacy device-trees don't have OPP table and must be updated */ > >> + if (!device_property_present(&pdev->dev, "operating-points-v2")) { > >> + dev_err(&pdev->dev, "OPP table not found, cannot continue\n"); > >> + dev_err(&pdev->dev, "please update your device tree\n"); > >> + return -ENODEV; > >> + } > > > > As you mentioned, it breaks the old dtb. I have no objection to improving > > the driver. Instead, you need confirmation from the Devicetree maintainer. > > Older DTBs will continue to work, but devfreq driver won't. We already > did this for other Tegra drivers before (CPUFREQ driver for example) and > Rob Herring confirmed that there is no problem here. OK. > > > And, > > I recommend that you use dev_pm_opp_of_get_opp_desc_node(&pdev->dev) > > to check whether a device contains opp-table or not. > > I'm not sure what are the benefits, this will make code less > expressive/readable and we will need to add extra of_node_put(), which > device_property_present() handles for us. > > Could you please give the rationale? IMO, 'operating-points-v2' word was defined on OPP core. I think that the external user of OPP better to use the public helper function instead of using the interval definition or value of OPP core directly. Basically, I prefer the provided helper function if there. But, it is not critical and doesn't affect the operation. If you want to keep, it is ok. > > >> + > >> tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL); > >> if (!tegra) > >> return -ENOMEM; > >> @@ -821,11 +818,29 @@ static int tegra_devfreq_probe(struct platform_device *pdev) > >> return err; > >> } > >> > >> + tegra->opp_table = dev_pm_opp_get_opp_table(&pdev->dev); > >> + if (IS_ERR(tegra->opp_table)) > >> + return dev_err_probe(&pdev->dev, PTR_ERR(tegra->opp_table), > >> + "Failed to prepare OPP table\n"); > > > > As I knew, each device can contain the opp_table on devicetree. > > It means that opp_table has not depended to another device driver. > > Did you see this exception case with EPROBE_DEFER error? > > OPP core will try to grab the clock reference for the table and it may > cause EPROBE_DEFER. Although, it shouldn't happen here because we have > devm_clk_get() before the get_opp_table(), hence seems the deferred > probe indeed shouldn't happen in this case. It is my missing point. If there, you're right. Could you provide the code point to check the clock reference on the OPP core?
Hi Dmitry, On Mon, Nov 2, 2020 at 12:24 AM Dmitry Osipenko <digetx@gmail.com> wrote: > > 01.11.2020 17:44, Chanwoo Choi пишет: > > Hi Dmitry, > > > > On Mon, Oct 26, 2020 at 7:22 AM Dmitry Osipenko <digetx@gmail.com> wrote: > >> > >> This patch moves ACTMON driver away from generating OPP table by itself, > >> transitioning it to use the table which comes from device-tree. This > >> change breaks compatibility with older device-trees in order to bring > >> support for the interconnect framework to the driver. This is a mandatory > >> change which needs to be done in order to implement interconnect-based > >> memory DVFS. Users of legacy device-trees will get a message telling that > >> theirs DT needs to be upgraded. Now ACTMON issues memory bandwidth request > >> using dev_pm_opp_set_bw(), instead of driving EMC clock rate directly. > >> > >> Tested-by: Peter Geis <pgwipeout@gmail.com> > >> Tested-by: Nicolas Chauvet <kwizart@gmail.com> > >> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> > >> --- > >> drivers/devfreq/tegra30-devfreq.c | 91 ++++++++++++++++--------------- > >> 1 file changed, 48 insertions(+), 43 deletions(-) > >> > >> diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c > >> index 3f732ab53573..1b0b91a71886 100644 > >> --- a/drivers/devfreq/tegra30-devfreq.c > >> +++ b/drivers/devfreq/tegra30-devfreq.c > >> @@ -19,6 +19,8 @@ > >> #include <linux/reset.h> > >> #include <linux/workqueue.h> > >> > >> +#include <soc/tegra/fuse.h> > >> + > > > > This patch touches the OPP. Is it related to this change? > > Yes, this is needed for the dev_pm_opp_set_supported_hw(). OK. > > >> #include "governor.h" > >> > >> #define ACTMON_GLB_STATUS 0x0 > >> @@ -155,6 +157,7 @@ struct tegra_devfreq_device { > >> > >> struct tegra_devfreq { > >> struct devfreq *devfreq; > >> + struct opp_table *opp_table; > >> > >> struct reset_control *reset; > >> struct clk *clock; > >> @@ -612,34 +615,19 @@ static void tegra_actmon_stop(struct tegra_devfreq *tegra) > >> static int tegra_devfreq_target(struct device *dev, unsigned long *freq, > >> u32 flags) > >> { > >> - struct tegra_devfreq *tegra = dev_get_drvdata(dev); > >> - struct devfreq *devfreq = tegra->devfreq; > >> struct dev_pm_opp *opp; > >> - unsigned long rate; > >> - int err; > >> + int ret; > >> > >> opp = devfreq_recommended_opp(dev, freq, flags); > >> if (IS_ERR(opp)) { > >> - dev_err(dev, "Failed to find opp for %lu Hz\n", *freq); > >> + dev_err(dev, "failed to find opp for %lu Hz\n", *freq); > > > > You used the 'Failed to' format in almost every error case. > > Don't need to change it. > > (snip) > > Good catch, thanks.
01.11.2020 18:44, Chanwoo Choi пишет: >> OPP core will try to grab the clock reference for the table and it may >> cause EPROBE_DEFER. Although, it shouldn't happen here because we have >> devm_clk_get() before the get_opp_table(), hence seems the deferred >> probe indeed shouldn't happen in this case. > It is my missing point. If there, you're right. > Could you provide the code point to check the clock reference on the OPP core? Please see it here: https://elixir.bootlin.com/linux/v5.10-rc1/source/drivers/opp/core.c#L1101
On Mon, Nov 2, 2020 at 12:49 AM Dmitry Osipenko <digetx@gmail.com> wrote: > > 01.11.2020 18:44, Chanwoo Choi пишет: > >> OPP core will try to grab the clock reference for the table and it may > >> cause EPROBE_DEFER. Although, it shouldn't happen here because we have > >> devm_clk_get() before the get_opp_table(), hence seems the deferred > >> probe indeed shouldn't happen in this case. > > It is my missing point. If there, you're right. > > Could you provide the code point to check the clock reference on the OPP core? > > Please see it here: > > https://elixir.bootlin.com/linux/v5.10-rc1/source/drivers/opp/core.c#L1101 Thanks. It seems that if device tree node contains the any node, it is not EPROBE_DEFER because of just using "clk_get(dev, NULL)". The patch[1] used the 'dev_err_probe' for getting the "emc" clock. Do you need to check it more? [1] https://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux.git/commit/?h=devfreq-next&id=09d56d92ad25b58113f4ec677e9b1ac1e2c3072b
01.11.2020 18:57, Chanwoo Choi пишет: > On Mon, Nov 2, 2020 at 12:49 AM Dmitry Osipenko <digetx@gmail.com> wrote: >> >> 01.11.2020 18:44, Chanwoo Choi пишет: >>>> OPP core will try to grab the clock reference for the table and it may >>>> cause EPROBE_DEFER. Although, it shouldn't happen here because we have >>>> devm_clk_get() before the get_opp_table(), hence seems the deferred >>>> probe indeed shouldn't happen in this case. >>> It is my missing point. If there, you're right. >>> Could you provide the code point to check the clock reference on the OPP core? >> >> Please see it here: >> >> https://elixir.bootlin.com/linux/v5.10-rc1/source/drivers/opp/core.c#L1101 > > Thanks. It seems that if device tree node contains the any node, > it is not EPROBE_DEFER because of just using "clk_get(dev, NULL)". > > The patch[1] used the 'dev_err_probe' for getting the "emc" clock. > Do you need to check it more? > > [1] https://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux.git/commit/?h=devfreq-next&id=09d56d92ad25b58113f4ec677e9b1ac1e2c3072b It should be safe to assume that the EPROBE_DEFER won't happen for dev_pm_opp_get_opp_table(). I'll improve it in v7, thanks.
01.11.2020 18:44, Chanwoo Choi пишет: >>> I recommend that you use dev_pm_opp_of_get_opp_desc_node(&pdev->dev) >>> to check whether a device contains opp-table or not. >> I'm not sure what are the benefits, this will make code less >> expressive/readable and we will need to add extra of_node_put(), which >> device_property_present() handles for us. >> >> Could you please give the rationale? > IMO, 'operating-points-v2' word was defined on OPP core. I think that > the external user > of OPP better to use the public helper function instead of using the > interval definition > or value of OPP core directly. Basically, I prefer the provided helper > function if there. > But, it is not critical and doesn't affect the operation. If you want > to keep, it is ok. > I'll prefer to keep it since it's better for the readability of the code, thanks.
diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c index 3f732ab53573..1b0b91a71886 100644 --- a/drivers/devfreq/tegra30-devfreq.c +++ b/drivers/devfreq/tegra30-devfreq.c @@ -19,6 +19,8 @@ #include <linux/reset.h> #include <linux/workqueue.h> +#include <soc/tegra/fuse.h> + #include "governor.h" #define ACTMON_GLB_STATUS 0x0 @@ -155,6 +157,7 @@ struct tegra_devfreq_device { struct tegra_devfreq { struct devfreq *devfreq; + struct opp_table *opp_table; struct reset_control *reset; struct clk *clock; @@ -612,34 +615,19 @@ static void tegra_actmon_stop(struct tegra_devfreq *tegra) static int tegra_devfreq_target(struct device *dev, unsigned long *freq, u32 flags) { - struct tegra_devfreq *tegra = dev_get_drvdata(dev); - struct devfreq *devfreq = tegra->devfreq; struct dev_pm_opp *opp; - unsigned long rate; - int err; + int ret; opp = devfreq_recommended_opp(dev, freq, flags); if (IS_ERR(opp)) { - dev_err(dev, "Failed to find opp for %lu Hz\n", *freq); + dev_err(dev, "failed to find opp for %lu Hz\n", *freq); return PTR_ERR(opp); } - rate = dev_pm_opp_get_freq(opp); - dev_pm_opp_put(opp); - - err = clk_set_min_rate(tegra->emc_clock, rate * KHZ); - if (err) - return err; - - err = clk_set_rate(tegra->emc_clock, 0); - if (err) - goto restore_min_rate; - return 0; - -restore_min_rate: - clk_set_min_rate(tegra->emc_clock, devfreq->previous_freq); + ret = dev_pm_opp_set_bw(dev, opp); + dev_pm_opp_put(opp); - return err; + return ret; } static int tegra_devfreq_get_dev_status(struct device *dev, @@ -655,7 +643,7 @@ static int tegra_devfreq_get_dev_status(struct device *dev, stat->private_data = tegra; /* The below are to be used by the other governors */ - stat->current_frequency = cur_freq; + stat->current_frequency = cur_freq * KHZ; actmon_dev = &tegra->devices[MCALL]; @@ -705,7 +693,7 @@ static int tegra_governor_get_target(struct devfreq *devfreq, target_freq = max(target_freq, dev->target_freq); } - *freq = target_freq; + *freq = target_freq * KHZ; return 0; } @@ -773,13 +761,22 @@ static struct devfreq_governor tegra_devfreq_governor = { static int tegra_devfreq_probe(struct platform_device *pdev) { + u32 hw_version = BIT(tegra_sku_info.soc_speedo_id); struct tegra_devfreq_device *dev; struct tegra_devfreq *tegra; + struct opp_table *opp_table; struct devfreq *devfreq; unsigned int i; long rate; int err; + /* legacy device-trees don't have OPP table and must be updated */ + if (!device_property_present(&pdev->dev, "operating-points-v2")) { + dev_err(&pdev->dev, "OPP table not found, cannot continue\n"); + dev_err(&pdev->dev, "please update your device tree\n"); + return -ENODEV; + } + tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL); if (!tegra) return -ENOMEM; @@ -821,11 +818,29 @@ static int tegra_devfreq_probe(struct platform_device *pdev) return err; } + tegra->opp_table = dev_pm_opp_get_opp_table(&pdev->dev); + if (IS_ERR(tegra->opp_table)) + return dev_err_probe(&pdev->dev, PTR_ERR(tegra->opp_table), + "Failed to prepare OPP table\n"); + + opp_table = dev_pm_opp_set_supported_hw(&pdev->dev, &hw_version, 1); + err = PTR_ERR_OR_ZERO(opp_table); + if (err) { + dev_err(&pdev->dev, "Failed to set supported HW: %d\n", err); + goto put_table; + } + + err = dev_pm_opp_of_add_table(&pdev->dev); + if (err) { + dev_err(&pdev->dev, "Failed to add OPP table: %d\n", err); + goto put_hw; + } + err = clk_prepare_enable(tegra->clock); if (err) { dev_err(&pdev->dev, "Failed to prepare and enable ACTMON clock\n"); - return err; + goto remove_table; } err = reset_control_reset(tegra->reset); @@ -849,23 +864,6 @@ static int tegra_devfreq_probe(struct platform_device *pdev) dev->regs = tegra->regs + dev->config->offset; } - for (rate = 0; rate <= tegra->max_freq * KHZ; rate++) { - rate = clk_round_rate(tegra->emc_clock, rate); - - if (rate < 0) { - dev_err(&pdev->dev, - "Failed to round clock rate: %ld\n", rate); - err = rate; - goto remove_opps; - } - - err = dev_pm_opp_add(&pdev->dev, rate / KHZ, 0); - if (err) { - dev_err(&pdev->dev, "Failed to add OPP: %d\n", err); - goto remove_opps; - } - } - platform_set_drvdata(pdev, tegra); tegra->clk_rate_change_nb.notifier_call = tegra_actmon_clk_notify_cb; @@ -881,7 +879,6 @@ static int tegra_devfreq_probe(struct platform_device *pdev) } tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock); - tegra_devfreq_profile.initial_freq /= KHZ; devfreq = devfreq_add_device(&pdev->dev, &tegra_devfreq_profile, "tegra_actmon", NULL); @@ -901,6 +898,12 @@ static int tegra_devfreq_probe(struct platform_device *pdev) reset_control_reset(tegra->reset); disable_clk: clk_disable_unprepare(tegra->clock); +remove_table: + dev_pm_opp_of_remove_table(&pdev->dev); +put_hw: + dev_pm_opp_put_supported_hw(tegra->opp_table); +put_table: + dev_pm_opp_put_opp_table(tegra->opp_table); return err; } @@ -912,11 +915,13 @@ static int tegra_devfreq_remove(struct platform_device *pdev) devfreq_remove_device(tegra->devfreq); devfreq_remove_governor(&tegra_devfreq_governor); - dev_pm_opp_remove_all_dynamic(&pdev->dev); - reset_control_reset(tegra->reset); clk_disable_unprepare(tegra->clock); + dev_pm_opp_of_remove_table(&pdev->dev); + dev_pm_opp_put_supported_hw(tegra->opp_table); + dev_pm_opp_put_opp_table(tegra->opp_table); + return 0; }