v4: Fixed error handling in __genpd_dev_pm_attach()
This is a re-spin of the series [1] which was adding support for a new
DT binding (assigned-performance-state) and based on the discussions on
that thread [2] it was concluded that we could achieve the same with the
existing 'required-opps' binding instead.
So this series, just drops the new binding and uses required-opps to achieve
the default perf state setting thats needed by some devices.
---
Some devics within power-domains with performance states do not
support DVFS, but still need to vote on a default/static state
while they are active. Add support for this using the 'required-opps'
property in device tree.
[1] https://lore.kernel.org/patchwork/project/lkml/list/?series=501336&state=%2A&archive=both
[2] https://lore.kernel.org/patchwork/patch/1436886/
Rajendra Nayak (2):
PM / Domains: Add support for 'required-opps' to set default perf
state
arm64: dts: sc7180: Add required-opps for i2c
arch/arm64/boot/dts/qcom/sc7180.dtsi | 24 +++++++++++++++++++++++
drivers/base/power/domain.c | 37 +++++++++++++++++++++++++++++++++---
include/linux/pm_domain.h | 1 +
3 files changed, 59 insertions(+), 3 deletions(-)
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation
Some devics within power domains with performance states do not
support DVFS, but still need to vote on a default/static state
while they are active. They can express this using the 'required-opps'
property in device tree, which points to the phandle of the OPP
supported by the corresponding power-domains.
Add support to parse this information from DT and then set the
specified performance state during attach and drop it on detach.
Also drop/set as part of runtime suspend/resume callbacks.
Signed-off-by: Rajendra Nayak <[email protected]>
---
drivers/base/power/domain.c | 37 ++++++++++++++++++++++++++++++++++---
include/linux/pm_domain.h | 1 +
2 files changed, 35 insertions(+), 3 deletions(-)
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index a934c67..dcc0b71 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -917,6 +917,10 @@ static int genpd_runtime_suspend(struct device *dev)
if (irq_safe_dev_in_no_sleep_domain(dev, genpd))
return 0;
+ /* Drop the default performance state */
+ if (dev_gpd_data(dev)->default_pstate)
+ dev_pm_genpd_set_performance_state(dev, 0);
+
genpd_lock(genpd);
gpd_data->rpm_pstate = genpd_drop_performance_state(dev);
genpd_power_off(genpd, true, 0);
@@ -937,6 +941,7 @@ static int genpd_runtime_resume(struct device *dev)
{
struct generic_pm_domain *genpd;
struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
+ unsigned int default_pstate = gpd_data->default_pstate;
struct gpd_timing_data *td = &gpd_data->td;
bool runtime_pm = pm_runtime_enabled(dev);
ktime_t time_start;
@@ -968,6 +973,9 @@ static int genpd_runtime_resume(struct device *dev)
if (ret)
return ret;
+ /* Set the default performance state */
+ if (default_pstate)
+ dev_pm_genpd_set_performance_state(dev, default_pstate);
out:
/* Measure resume latency. */
time_start = 0;
@@ -1000,6 +1008,8 @@ static int genpd_runtime_resume(struct device *dev)
genpd_stop_dev(genpd, dev);
err_poweroff:
if (!pm_runtime_is_irq_safe(dev) || genpd_is_irq_safe(genpd)) {
+ if (default_pstate)
+ dev_pm_genpd_set_performance_state(dev, 0);
genpd_lock(genpd);
gpd_data->rpm_pstate = genpd_drop_performance_state(dev);
genpd_power_off(genpd, true, 0);
@@ -2598,6 +2608,12 @@ static void genpd_dev_pm_detach(struct device *dev, bool power_off)
dev_dbg(dev, "removing from PM domain %s\n", pd->name);
+ /* Drop the default performance state */
+ if (dev_gpd_data(dev)->default_pstate) {
+ dev_pm_genpd_set_performance_state(dev, 0);
+ dev_gpd_data(dev)->default_pstate = 0;
+ }
+
for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
ret = genpd_remove_device(pd, dev);
if (ret != -EAGAIN)
@@ -2635,9 +2651,10 @@ static void genpd_dev_pm_sync(struct device *dev)
static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
unsigned int index, bool power_on)
{
+ struct device_node *np;
struct of_phandle_args pd_args;
struct generic_pm_domain *pd;
- int ret;
+ int ret, pstate;
ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
"#power-domain-cells", index, &pd_args);
@@ -2675,10 +2692,24 @@ static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
genpd_unlock(pd);
}
- if (ret)
+ if (ret) {
genpd_remove_device(pd, dev);
+ return -EPROBE_DEFER;
+ }
+
+ /* Set the default performance state */
+ np = base_dev->of_node;
+ if (of_parse_phandle(np, "required-opps", index)) {
+ pstate = of_get_required_opp_performance_state(np, index);
+ if (pstate < 0) {
+ dev_err(dev, "failed to set pstate:%d", pstate);
+ ret = pstate;
+ }
+ dev_pm_genpd_set_performance_state(dev, pstate);
+ dev_gpd_data(dev)->default_pstate = pstate;
+ }
- return ret ? -EPROBE_DEFER : 1;
+ return ret ? ret : 1;
}
/**
diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
index 21a0577..67017c9 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h
@@ -198,6 +198,7 @@ struct generic_pm_domain_data {
struct notifier_block *power_nb;
int cpu;
unsigned int performance_state;
+ unsigned int default_pstate;
unsigned int rpm_pstate;
ktime_t next_wakeup;
void *data;
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation
Quoting Rajendra Nayak (2021-07-16 03:00:57)
> Some devics within power domains with performance states do not
devices
> support DVFS, but still need to vote on a default/static state
> while they are active. They can express this using the 'required-opps'
> property in device tree, which points to the phandle of the OPP
> supported by the corresponding power-domains.
>
> Add support to parse this information from DT and then set the
> specified performance state during attach and drop it on detach.
> Also drop/set as part of runtime suspend/resume callbacks.
>
> Signed-off-by: Rajendra Nayak <[email protected]>
> ---
> drivers/base/power/domain.c | 37 ++++++++++++++++++++++++++++++++++---
> include/linux/pm_domain.h | 1 +
> 2 files changed, 35 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> index a934c67..dcc0b71 100644
> --- a/drivers/base/power/domain.c
> +++ b/drivers/base/power/domain.c
> @@ -1000,6 +1008,8 @@ static int genpd_runtime_resume(struct device *dev)
> genpd_stop_dev(genpd, dev);
> err_poweroff:
> if (!pm_runtime_is_irq_safe(dev) || genpd_is_irq_safe(genpd)) {
> + if (default_pstate)
> + dev_pm_genpd_set_performance_state(dev, 0);
> genpd_lock(genpd);
> gpd_data->rpm_pstate = genpd_drop_performance_state(dev);
Maybe this should be
prev_state = genpd_drop_performance_state(dev);
if (!default_pstate)
gdp_data->rpm_pstate = prev_state;
so we don't call dev_pm_genpd_set_performance_state() effectively twice?
Also it would make sure we call dev_pm_genpd_set_performance_state()
underneath the genpd_lock() if that is important. Similarly do that on
suspend path.
> genpd_power_off(genpd, true, 0);
> @@ -2598,6 +2608,12 @@ static void genpd_dev_pm_detach(struct device *dev, bool power_off)
>
> dev_dbg(dev, "removing from PM domain %s\n", pd->name);
>
> + /* Drop the default performance state */
> + if (dev_gpd_data(dev)->default_pstate) {
> + dev_pm_genpd_set_performance_state(dev, 0);
> + dev_gpd_data(dev)->default_pstate = 0;
> + }
> +
> for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
> ret = genpd_remove_device(pd, dev);
> if (ret != -EAGAIN)
> @@ -2675,10 +2692,24 @@ static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
> genpd_unlock(pd);
> }
>
> - if (ret)
> + if (ret) {
> genpd_remove_device(pd, dev);
> + return -EPROBE_DEFER;
> + }
> +
> + /* Set the default performance state */
> + np = base_dev->of_node;
> + if (of_parse_phandle(np, "required-opps", index)) {
> + pstate = of_get_required_opp_performance_state(np, index);
> + if (pstate < 0) {
> + dev_err(dev, "failed to set pstate:%d", pstate);
Missing newline on printk. Also can we spell out pstate as "failed to
set required performance state %d for power-domain %d"?
> + ret = pstate;
> + }
> + dev_pm_genpd_set_performance_state(dev, pstate);
> + dev_gpd_data(dev)->default_pstate = pstate;
> + }
>
> - return ret ? -EPROBE_DEFER : 1;
> + return ret ? ret : 1;
> }
>
> /**
On 7/17/2021 1:49 AM, Stephen Boyd wrote:
> Quoting Rajendra Nayak (2021-07-16 03:00:57)
>> Some devics within power domains with performance states do not
>
> devices
>
>> support DVFS, but still need to vote on a default/static state
>> while they are active. They can express this using the 'required-opps'
>> property in device tree, which points to the phandle of the OPP
>> supported by the corresponding power-domains.
>>
>> Add support to parse this information from DT and then set the
>> specified performance state during attach and drop it on detach.
>> Also drop/set as part of runtime suspend/resume callbacks.
>>
>> Signed-off-by: Rajendra Nayak <[email protected]>
>> ---
>> drivers/base/power/domain.c | 37 ++++++++++++++++++++++++++++++++++---
>> include/linux/pm_domain.h | 1 +
>> 2 files changed, 35 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
>> index a934c67..dcc0b71 100644
>> --- a/drivers/base/power/domain.c
>> +++ b/drivers/base/power/domain.c
>> @@ -1000,6 +1008,8 @@ static int genpd_runtime_resume(struct device *dev)
>> genpd_stop_dev(genpd, dev);
>> err_poweroff:
>> if (!pm_runtime_is_irq_safe(dev) || genpd_is_irq_safe(genpd)) {
>> + if (default_pstate)
>> + dev_pm_genpd_set_performance_state(dev, 0);
>> genpd_lock(genpd);
>> gpd_data->rpm_pstate = genpd_drop_performance_state(dev);
>
> Maybe this should be
>
> prev_state = genpd_drop_performance_state(dev);
> if (!default_pstate)
> gdp_data->rpm_pstate = prev_state;
>
> so we don't call dev_pm_genpd_set_performance_state() effectively twice?
> Also it would make sure we call dev_pm_genpd_set_performance_state()
> underneath the genpd_lock() if that is important. Similarly do that on
> suspend path.
looking through this more, I think I can completely drop any special
handling for default_pstate in runtime suspend and resume. The existing
drop/restore login Ulf has added should take care of it.
I'll test and respin soon.
>
>> genpd_power_off(genpd, true, 0);
>> @@ -2598,6 +2608,12 @@ static void genpd_dev_pm_detach(struct device *dev, bool power_off)
>>
>> dev_dbg(dev, "removing from PM domain %s\n", pd->name);
>>
>> + /* Drop the default performance state */
>> + if (dev_gpd_data(dev)->default_pstate) {
>> + dev_pm_genpd_set_performance_state(dev, 0);
>> + dev_gpd_data(dev)->default_pstate = 0;
>> + }
>> +
>> for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
>> ret = genpd_remove_device(pd, dev);
>> if (ret != -EAGAIN)
>> @@ -2675,10 +2692,24 @@ static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
>> genpd_unlock(pd);
>> }
>>
>> - if (ret)
>> + if (ret) {
>> genpd_remove_device(pd, dev);
>> + return -EPROBE_DEFER;
>> + }
>> +
>> + /* Set the default performance state */
>> + np = base_dev->of_node;
>> + if (of_parse_phandle(np, "required-opps", index)) {
>> + pstate = of_get_required_opp_performance_state(np, index);
>> + if (pstate < 0) {
>> + dev_err(dev, "failed to set pstate:%d", pstate);
>
> Missing newline on printk. Also can we spell out pstate as "failed to
> set required performance state %d for power-domain %d"?
thanks, will fix when I respin.
Thanks for the review.
>
>> + ret = pstate;
>> + }
>> + dev_pm_genpd_set_performance_state(dev, pstate);
>> + dev_gpd_data(dev)->default_pstate = pstate;
>> + }
>>
>> - return ret ? -EPROBE_DEFER : 1;
>> + return ret ? ret : 1;
>> }
>>
>> /**
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation