| Message ID | 20180612044052.4402-1-rnayak@codeaurora.org |
|---|---|
| Headers | show |
| Series | Add powerdomain driver for corners on msm8996/sdm845 | expand |
On 12 June 2018 at 06:40, Rajendra Nayak <rnayak@codeaurora.org> wrote: > Changes in v3: > * Bindings split into seperate patches > * Bindings updated to remove duplicate OPP table phandles > * DT headers defining macros for Power domain indexes and OPP levels > * Optimisations to use rpmh_write_async() whereever applicable > * Fixed up handling of ACTIVE_ONLY/WAKE_ONLY/SLEEP voting for RPMh > * Fixed the vlvl to hlvl conversions in set_performance > * Other minor fixes based on review of v2 > * TODO: This series does not handle the case where all VDD_MX votes > should be higher than VDD_CX from APPs, as pointed out > by David Collins in v2. This needs support at genpd to propogate performance > state up the parents, if we model these as Parent/Child to handle the > interdependency. > > Changes in v2: > * added a powerdomain driver for sdm845 which supports communicating to RPMh > * dropped the changes to sdhc driver to move over to using OPP > as there is active discussion on using OPP as the interface vs > handling all of it in clock drivers > * Other minor binding updates based on review of v1 > > With performance state support for genpd/OPP merged, this is an effort > to model a powerdomain driver to communicate corner/level > values for qualcomm platforms to RPM (Remote Power Manager) and RPMh. > > Rajendra Nayak (7): > dt-bindings: power: Add qcom rpm power domain driver bindings > soc: qcom: rpmpd: Add a Power domain driver to model corners > soc: qcom: rpmpd: Add support for get/set performance state > arm64: dts: msm8996: Add rpmpd device node > dt-bindings: power: Add qcom rpmh power domain driver bindings > soc: qcom: Add RPMh Power domain driver > soc: qcom: rpmpd/rpmhpd: Add a max vote on all corners at init > > .../devicetree/bindings/power/qcom,rpmhpd.txt | 65 +++ > .../devicetree/bindings/power/qcom,rpmpd.txt | 49 ++ > arch/arm64/boot/dts/qcom/msm8996.dtsi | 34 ++ > drivers/soc/qcom/Kconfig | 18 + > drivers/soc/qcom/Makefile | 2 + > drivers/soc/qcom/rpmhpd.c | 437 ++++++++++++++++++ > drivers/soc/qcom/rpmpd.c | 356 ++++++++++++++ > include/dt-bindings/power/qcom-rpmhpd.h | 31 ++ > include/dt-bindings/power/qcom-rpmpd.h | 16 + > 9 files changed, 1008 insertions(+) > create mode 100644 Documentation/devicetree/bindings/power/qcom,rpmhpd.txt > create mode 100644 Documentation/devicetree/bindings/power/qcom,rpmpd.txt > create mode 100644 drivers/soc/qcom/rpmhpd.c > create mode 100644 drivers/soc/qcom/rpmpd.c > create mode 100644 include/dt-bindings/power/qcom-rpmhpd.h > create mode 100644 include/dt-bindings/power/qcom-rpmpd.h > > -- > QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member > of Code Aurora Forum, hosted by The Linux Foundation > For the series: Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hello Rajendra, On 06/11/2018 09:40 PM, Rajendra Nayak wrote: > As we move from no clients/consumers in kernel voting on corners, > to *some* voting and some not voting, we might end up in a situation > where the clients which remove votes can adversly impact others s/adversly/adversely/ > who still don't have a way to vote. > > To avoid this situation, have a max vote on all corners at init. > This should/can be removed once we have all clients moved to > be able to vote/unvote for themselves. This change seems like a hack. Do you intend for it to be merged and then later reverted in Linus's tree? Could it instead be implemented in a way that does not require reverting and instead is enabled by some DT property? Alternatively, could this feature be added to the power domain core since it is relatively generic? > Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org> > Acked-by: Viresh Kumar <viresh.kumar@linaro.org> > --- > drivers/soc/qcom/rpmhpd.c | 12 +++++++++++- > drivers/soc/qcom/rpmpd.c | 9 +++++++++ > 2 files changed, 20 insertions(+), 1 deletion(-) > > diff --git a/drivers/soc/qcom/rpmhpd.c b/drivers/soc/qcom/rpmhpd.c > index 7083ec1590ff..3c753d33aeee 100644 > --- a/drivers/soc/qcom/rpmhpd.c > +++ b/drivers/soc/qcom/rpmhpd.c > @@ -329,7 +329,7 @@ static int rpmhpd_update_level_mapping(struct rpmhpd *rpmhpd) > > static int rpmhpd_probe(struct platform_device *pdev) > { > - int i, ret; > + int i, ret, max_level; > size_t num; > struct genpd_onecell_data *data; > struct rpmhpd **rpmhpds; > @@ -390,6 +390,16 @@ static int rpmhpd_probe(struct platform_device *pdev) > pm_genpd_init(&rpmhpds[i]->pd, NULL, true); > > data->domains[i] = &rpmhpds[i]->pd; > + > + /* > + * Until we have all consumers voting on corners > + * just vote the max corner on all PDs > + * This should ideally be *removed* once we have > + * all (most) consumers being able to vote > + */ > + max_level = rpmhpds[i]->level_count - 1; > + rpmhpd_set_performance(&rpmhpds[i]->pd, rpmhpds[i]->level[max_level]); > + rpmhpd_power_on(&rpmhpds[i]->pd); Clearly these calls will result in max level requests being sent for all power domains at probe time. However, it isn't clear that this will actually help at runtime in these two cases: 1. A consumer enables and then disables a power domain. - It seems like the PD would just be disabled in this case. 2. A consumer sets a non-max performance state of a power domain. - It seems like the PD would just be set to the new lower performance state since the max vote isn't known to the PD core for aggregation purposes. Thanks, David
On 06/14/2018 03:58 AM, David Collins wrote: > Hello Rajendra, > > On 06/11/2018 09:40 PM, Rajendra Nayak wrote: >> As we move from no clients/consumers in kernel voting on corners, >> to *some* voting and some not voting, we might end up in a situation >> where the clients which remove votes can adversly impact others > > s/adversly/adversely/ > >> who still don't have a way to vote. >> >> To avoid this situation, have a max vote on all corners at init. >> This should/can be removed once we have all clients moved to >> be able to vote/unvote for themselves. > > This change seems like a hack. Do you intend for it to be merged and then > later reverted in Linus's tree? Could it instead be implemented in a way > that does not require reverting and instead is enabled by some DT > property? Alternatively, could this feature be added to the power domain > core since it is relatively generic? > > >> Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org> >> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> >> --- >> drivers/soc/qcom/rpmhpd.c | 12 +++++++++++- >> drivers/soc/qcom/rpmpd.c | 9 +++++++++ >> 2 files changed, 20 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/soc/qcom/rpmhpd.c b/drivers/soc/qcom/rpmhpd.c >> index 7083ec1590ff..3c753d33aeee 100644 >> --- a/drivers/soc/qcom/rpmhpd.c >> +++ b/drivers/soc/qcom/rpmhpd.c >> @@ -329,7 +329,7 @@ static int rpmhpd_update_level_mapping(struct rpmhpd *rpmhpd) >> >> static int rpmhpd_probe(struct platform_device *pdev) >> { >> - int i, ret; >> + int i, ret, max_level; >> size_t num; >> struct genpd_onecell_data *data; >> struct rpmhpd **rpmhpds; >> @@ -390,6 +390,16 @@ static int rpmhpd_probe(struct platform_device *pdev) >> pm_genpd_init(&rpmhpds[i]->pd, NULL, true); >> >> data->domains[i] = &rpmhpds[i]->pd; >> + >> + /* >> + * Until we have all consumers voting on corners >> + * just vote the max corner on all PDs >> + * This should ideally be *removed* once we have >> + * all (most) consumers being able to vote >> + */ >> + max_level = rpmhpds[i]->level_count - 1; >> + rpmhpd_set_performance(&rpmhpds[i]->pd, rpmhpds[i]->level[max_level]); >> + rpmhpd_power_on(&rpmhpds[i]->pd); > > Clearly these calls will result in max level requests being sent for all > power domains at probe time. However, it isn't clear that this will > actually help at runtime in these two cases: > > 1. A consumer enables and then disables a power domain. > - It seems like the PD would just be disabled in this case. > > 2. A consumer sets a non-max performance state of a power domain. > - It seems like the PD would just be set to the new lower > performance state since the max vote isn't known to the > PD core for aggregation purposes. Yes, you are right. I certainly did not seem to have thought through this enough. A need for something like this came up at a point where genpd could not deal with devices with multiple power domains. So the concern at that point was that if some consumers (which only need to vote on one corner) move to using this driver, while some others (which need to vote on multiple corners) cannot, we would end up breaking them. That does not seem to be true anymore since we do have patches from Ulf which support having devices with multiple power domains attached which can be controlled individually. So if some consumer voting makes some others break, they should just be fixed and patched to vote as well. If all this gets handled centrally from within the clock drivers then we most likely won't even end up with a situation like this. I think I will just drop this one unless Stephen/Viresh still see an issue with some early voters breaking others.
On 14-06-18, 12:05, Rajendra Nayak wrote: > On 06/14/2018 03:58 AM, David Collins wrote: > > Hello Rajendra, > > > > On 06/11/2018 09:40 PM, Rajendra Nayak wrote: > >> As we move from no clients/consumers in kernel voting on corners, > >> to *some* voting and some not voting, we might end up in a situation > >> where the clients which remove votes can adversly impact others > > > > s/adversly/adversely/ > > > >> who still don't have a way to vote. > >> > >> To avoid this situation, have a max vote on all corners at init. > >> This should/can be removed once we have all clients moved to > >> be able to vote/unvote for themselves. > > > > This change seems like a hack. Do you intend for it to be merged and then > > later reverted in Linus's tree? Could it instead be implemented in a way > > that does not require reverting and instead is enabled by some DT > > property? Alternatively, could this feature be added to the power domain > > core since it is relatively generic? > > > > > >> Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org> > >> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> > >> --- > >> drivers/soc/qcom/rpmhpd.c | 12 +++++++++++- > >> drivers/soc/qcom/rpmpd.c | 9 +++++++++ > >> 2 files changed, 20 insertions(+), 1 deletion(-) > >> > >> diff --git a/drivers/soc/qcom/rpmhpd.c b/drivers/soc/qcom/rpmhpd.c > >> index 7083ec1590ff..3c753d33aeee 100644 > >> --- a/drivers/soc/qcom/rpmhpd.c > >> +++ b/drivers/soc/qcom/rpmhpd.c > >> @@ -329,7 +329,7 @@ static int rpmhpd_update_level_mapping(struct rpmhpd *rpmhpd) > >> > >> static int rpmhpd_probe(struct platform_device *pdev) > >> { > >> - int i, ret; > >> + int i, ret, max_level; > >> size_t num; > >> struct genpd_onecell_data *data; > >> struct rpmhpd **rpmhpds; > >> @@ -390,6 +390,16 @@ static int rpmhpd_probe(struct platform_device *pdev) > >> pm_genpd_init(&rpmhpds[i]->pd, NULL, true); > >> > >> data->domains[i] = &rpmhpds[i]->pd; > >> + > >> + /* > >> + * Until we have all consumers voting on corners > >> + * just vote the max corner on all PDs > >> + * This should ideally be *removed* once we have > >> + * all (most) consumers being able to vote > >> + */ > >> + max_level = rpmhpds[i]->level_count - 1; > >> + rpmhpd_set_performance(&rpmhpds[i]->pd, rpmhpds[i]->level[max_level]); > >> + rpmhpd_power_on(&rpmhpds[i]->pd); > > > > Clearly these calls will result in max level requests being sent for all > > power domains at probe time. However, it isn't clear that this will > > actually help at runtime in these two cases: > > > > 1. A consumer enables and then disables a power domain. > > - It seems like the PD would just be disabled in this case. So instead of rpmhpd_power_on() we should be doing gepnd_power_on() or whatever the API is, so the user count stays at 1. > > 2. A consumer sets a non-max performance state of a power domain. > > - It seems like the PD would just be set to the new lower > > performance state since the max vote isn't known to the > > PD core for aggregation purposes. Right, and that's because the patch isn't implemented properly yet. I asked to do a fake vote from some user with their dev structure, so the vote always stays. > Yes, you are right. I certainly did not seem to have thought through this enough. > > A need for something like this came up at a point where genpd could not deal with > devices with multiple power domains. So the concern at that point was that if some > consumers (which only need to vote on one corner) move to using this driver, while > some others (which need to vote on multiple corners) cannot, we would end up breaking > them. > > That does not seem to be true anymore since we do have patches from Ulf which support > having devices with multiple power domains attached which can be controlled individually. > So if some consumer voting makes some others break, they should just be fixed and patched > to vote as well. If all this gets handled centrally from within the clock drivers then we > most likely won't even end up with a situation like this. > > I think I will just drop this one unless Stephen/Viresh still see an issue with some early > voters breaking others. So what if the LCD/DDR/etc are getting used at boot and someone requests a lower vote? Wouldn't we just break ?
On 19 June 2018 at 12:10, Viresh Kumar <viresh.kumar@linaro.org> wrote: > On 14-06-18, 12:05, Rajendra Nayak wrote: >> On 06/14/2018 03:58 AM, David Collins wrote: >> > Hello Rajendra, >> > >> > On 06/11/2018 09:40 PM, Rajendra Nayak wrote: >> >> As we move from no clients/consumers in kernel voting on corners, >> >> to *some* voting and some not voting, we might end up in a situation >> >> where the clients which remove votes can adversly impact others >> > >> > s/adversly/adversely/ >> > >> >> who still don't have a way to vote. >> >> >> >> To avoid this situation, have a max vote on all corners at init. >> >> This should/can be removed once we have all clients moved to >> >> be able to vote/unvote for themselves. >> > >> > This change seems like a hack. Do you intend for it to be merged and then >> > later reverted in Linus's tree? Could it instead be implemented in a way >> > that does not require reverting and instead is enabled by some DT >> > property? Alternatively, could this feature be added to the power domain >> > core since it is relatively generic? >> > >> > >> >> Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org> >> >> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> >> >> --- >> >> drivers/soc/qcom/rpmhpd.c | 12 +++++++++++- >> >> drivers/soc/qcom/rpmpd.c | 9 +++++++++ >> >> 2 files changed, 20 insertions(+), 1 deletion(-) >> >> >> >> diff --git a/drivers/soc/qcom/rpmhpd.c b/drivers/soc/qcom/rpmhpd.c >> >> index 7083ec1590ff..3c753d33aeee 100644 >> >> --- a/drivers/soc/qcom/rpmhpd.c >> >> +++ b/drivers/soc/qcom/rpmhpd.c >> >> @@ -329,7 +329,7 @@ static int rpmhpd_update_level_mapping(struct rpmhpd *rpmhpd) >> >> >> >> static int rpmhpd_probe(struct platform_device *pdev) >> >> { >> >> - int i, ret; >> >> + int i, ret, max_level; >> >> size_t num; >> >> struct genpd_onecell_data *data; >> >> struct rpmhpd **rpmhpds; >> >> @@ -390,6 +390,16 @@ static int rpmhpd_probe(struct platform_device *pdev) >> >> pm_genpd_init(&rpmhpds[i]->pd, NULL, true); >> >> >> >> data->domains[i] = &rpmhpds[i]->pd; >> >> + >> >> + /* >> >> + * Until we have all consumers voting on corners >> >> + * just vote the max corner on all PDs >> >> + * This should ideally be *removed* once we have >> >> + * all (most) consumers being able to vote >> >> + */ >> >> + max_level = rpmhpds[i]->level_count - 1; >> >> + rpmhpd_set_performance(&rpmhpds[i]->pd, rpmhpds[i]->level[max_level]); >> >> + rpmhpd_power_on(&rpmhpds[i]->pd); >> > >> > Clearly these calls will result in max level requests being sent for all >> > power domains at probe time. However, it isn't clear that this will >> > actually help at runtime in these two cases: >> > >> > 1. A consumer enables and then disables a power domain. >> > - It seems like the PD would just be disabled in this case. > > So instead of rpmhpd_power_on() we should be doing gepnd_power_on() or whatever > the API is, so the user count stays at 1. There is no such API. Instead a device needs to be attached to genpd and that's it. As long as the device don't enables runtime PM and that the device gets runtime suspended, genpd will remain powered on. > >> > 2. A consumer sets a non-max performance state of a power domain. >> > - It seems like the PD would just be set to the new lower >> > performance state since the max vote isn't known to the >> > PD core for aggregation purposes. > > Right, and that's because the patch isn't implemented properly yet. I asked to > do a fake vote from some user with their dev structure, so the vote always > stays. > >> Yes, you are right. I certainly did not seem to have thought through this enough. >> >> A need for something like this came up at a point where genpd could not deal with >> devices with multiple power domains. So the concern at that point was that if some >> consumers (which only need to vote on one corner) move to using this driver, while >> some others (which need to vote on multiple corners) cannot, we would end up breaking >> them. >> >> That does not seem to be true anymore since we do have patches from Ulf which support >> having devices with multiple power domains attached which can be controlled individually. >> So if some consumer voting makes some others break, they should just be fixed and patched >> to vote as well. If all this gets handled centrally from within the clock drivers then we >> most likely won't even end up with a situation like this. >> >> I think I will just drop this one unless Stephen/Viresh still see an issue with some early >> voters breaking others. > > So what if the LCD/DDR/etc are getting used at boot and someone requests a lower > vote? Wouldn't we just break ? Sounds like we need a way to manage votes for "boot constraints performance levels". :-) Anyway, to deal with this via the existing genpd APIs, we need to attach a device to a genpd and then call dev_pm_genpd_set_performance_state() on it. I guess at a late initcall, the votes can be dropped and the device can be detached. Or something along these lines. Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 06/25/2018 02:27 PM, Ulf Hansson wrote: > On 19 June 2018 at 12:10, Viresh Kumar <viresh.kumar@linaro.org> wrote: >> On 14-06-18, 12:05, Rajendra Nayak wrote: >>> On 06/14/2018 03:58 AM, David Collins wrote: >>>> Hello Rajendra, >>>> >>>> On 06/11/2018 09:40 PM, Rajendra Nayak wrote: >>>>> As we move from no clients/consumers in kernel voting on corners, >>>>> to *some* voting and some not voting, we might end up in a situation >>>>> where the clients which remove votes can adversly impact others >>>> >>>> s/adversly/adversely/ >>>> >>>>> who still don't have a way to vote. >>>>> >>>>> To avoid this situation, have a max vote on all corners at init. >>>>> This should/can be removed once we have all clients moved to >>>>> be able to vote/unvote for themselves. >>>> >>>> This change seems like a hack. Do you intend for it to be merged and then >>>> later reverted in Linus's tree? Could it instead be implemented in a way >>>> that does not require reverting and instead is enabled by some DT >>>> property? Alternatively, could this feature be added to the power domain >>>> core since it is relatively generic? >>>> >>>> >>>>> Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org> >>>>> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> >>>>> --- >>>>> drivers/soc/qcom/rpmhpd.c | 12 +++++++++++- >>>>> drivers/soc/qcom/rpmpd.c | 9 +++++++++ >>>>> 2 files changed, 20 insertions(+), 1 deletion(-) >>>>> >>>>> diff --git a/drivers/soc/qcom/rpmhpd.c b/drivers/soc/qcom/rpmhpd.c >>>>> index 7083ec1590ff..3c753d33aeee 100644 >>>>> --- a/drivers/soc/qcom/rpmhpd.c >>>>> +++ b/drivers/soc/qcom/rpmhpd.c >>>>> @@ -329,7 +329,7 @@ static int rpmhpd_update_level_mapping(struct rpmhpd *rpmhpd) >>>>> >>>>> static int rpmhpd_probe(struct platform_device *pdev) >>>>> { >>>>> - int i, ret; >>>>> + int i, ret, max_level; >>>>> size_t num; >>>>> struct genpd_onecell_data *data; >>>>> struct rpmhpd **rpmhpds; >>>>> @@ -390,6 +390,16 @@ static int rpmhpd_probe(struct platform_device *pdev) >>>>> pm_genpd_init(&rpmhpds[i]->pd, NULL, true); >>>>> >>>>> data->domains[i] = &rpmhpds[i]->pd; >>>>> + >>>>> + /* >>>>> + * Until we have all consumers voting on corners >>>>> + * just vote the max corner on all PDs >>>>> + * This should ideally be *removed* once we have >>>>> + * all (most) consumers being able to vote >>>>> + */ >>>>> + max_level = rpmhpds[i]->level_count - 1; >>>>> + rpmhpd_set_performance(&rpmhpds[i]->pd, rpmhpds[i]->level[max_level]); >>>>> + rpmhpd_power_on(&rpmhpds[i]->pd); >>>> >>>> Clearly these calls will result in max level requests being sent for all >>>> power domains at probe time. However, it isn't clear that this will >>>> actually help at runtime in these two cases: >>>> >>>> 1. A consumer enables and then disables a power domain. >>>> - It seems like the PD would just be disabled in this case. >> >> So instead of rpmhpd_power_on() we should be doing gepnd_power_on() or whatever >> the API is, so the user count stays at 1. > > There is no such API. > > Instead a device needs to be attached to genpd and that's it. As long > as the device don't enables runtime PM and that the device gets > runtime suspended, genpd will remain powered on. Its more to do with keeping the power domains at a desired 'performance level' than just keeping them on. > >> >>>> 2. A consumer sets a non-max performance state of a power domain. >>>> - It seems like the PD would just be set to the new lower >>>> performance state since the max vote isn't known to the >>>> PD core for aggregation purposes. >> >> Right, and that's because the patch isn't implemented properly yet. I asked to >> do a fake vote from some user with their dev structure, so the vote always >> stays. >> >>> Yes, you are right. I certainly did not seem to have thought through this enough. >>> >>> A need for something like this came up at a point where genpd could not deal with >>> devices with multiple power domains. So the concern at that point was that if some >>> consumers (which only need to vote on one corner) move to using this driver, while >>> some others (which need to vote on multiple corners) cannot, we would end up breaking >>> them. >>> >>> That does not seem to be true anymore since we do have patches from Ulf which support >>> having devices with multiple power domains attached which can be controlled individually. >>> So if some consumer voting makes some others break, they should just be fixed and patched >>> to vote as well. If all this gets handled centrally from within the clock drivers then we >>> most likely won't even end up with a situation like this. >>> >>> I think I will just drop this one unless Stephen/Viresh still see an issue with some early >>> voters breaking others. >> >> So what if the LCD/DDR/etc are getting used at boot and someone requests a lower >> vote? Wouldn't we just break ? > > Sounds like we need a way to manage votes for "boot constraints > performance levels". :-) Yes, I think we are mixing up whats needed for 'boot constraints' and what this patch was meant to do. Boot constraints is a generic problem not limited to power domains alone and this patch isn't trying to solve that.