This series registers for scmi limits change notifications to determine
the throttled frequency and apply HW pressure.
V4:
* Use EXPORT_SYMBOL_GPL instead. [Trilok]
* Use a interim variable to show the khz calc. [Lukasz]
* Use driver_data to pass on the handle and scmi_dev instead of using
global variables. Dropped Lukasz's Rb due to adding these minor
changes.
V3:
* Sanitize range_max received from the notifier. [Pierre]
* Drop patches 1/2 from v2. [Cristian]
* Update commit message in patch 2.
V2:
* Rename opp_xlate -> freq_xlate [Viresh]
* Export cpufreq_update_pressure and use it directly [Lukasz]
Depends on:
HW pressure v6: https://patchwork.kernel.org/project/linux-arm-msm/cover/[email protected]/
Sibi Sankar (2):
cpufreq: Export cpufreq_update_pressure
cpufreq: scmi: Register for limit change notifications
drivers/cpufreq/cpufreq.c | 3 ++-
drivers/cpufreq/scmi-cpufreq.c | 44 ++++++++++++++++++++++++++++++++++
include/linux/cpufreq.h | 2 ++
3 files changed, 48 insertions(+), 1 deletion(-)
--
2.34.1
Register for limit change notifications if supported and use the throttled
frequency from the notification to apply HW pressure.
Signed-off-by: Sibi Sankar <[email protected]>
---
v4:
* Use a interim variable to show the khz calc. [Lukasz]
* Use driver_data to pass on the handle and scmi_dev instead of using
global variables. Dropped Lukasz's Rb due to adding these minor
changes.
drivers/cpufreq/scmi-cpufreq.c | 44 ++++++++++++++++++++++++++++++++++
1 file changed, 44 insertions(+)
diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c
index 3b4f6bfb2f4c..d946b7a08258 100644
--- a/drivers/cpufreq/scmi-cpufreq.c
+++ b/drivers/cpufreq/scmi-cpufreq.c
@@ -21,11 +21,18 @@
#include <linux/types.h>
#include <linux/units.h>
+struct scmi_cpufreq_driver_data {
+ struct scmi_device *sdev;
+ const struct scmi_handle *handle;
+};
+
struct scmi_data {
int domain_id;
int nr_opp;
struct device *cpu_dev;
+ struct cpufreq_policy *policy;
cpumask_var_t opp_shared_cpus;
+ struct notifier_block limit_notify_nb;
};
static struct scmi_protocol_handle *ph;
@@ -174,6 +181,22 @@ static struct freq_attr *scmi_cpufreq_hw_attr[] = {
NULL,
};
+static int scmi_limit_notify_cb(struct notifier_block *nb, unsigned long event, void *data)
+{
+ struct scmi_data *priv = container_of(nb, struct scmi_data, limit_notify_nb);
+ struct scmi_perf_limits_report *limit_notify = data;
+ struct cpufreq_policy *policy = priv->policy;
+ unsigned int limit_freq_khz;
+
+ limit_freq_khz = limit_notify->range_max_freq / HZ_PER_KHZ;
+
+ policy->max = clamp(limit_freq_khz, policy->cpuinfo.min_freq, policy->cpuinfo.max_freq);
+
+ cpufreq_update_pressure(policy);
+
+ return NOTIFY_OK;
+}
+
static int scmi_cpufreq_init(struct cpufreq_policy *policy)
{
int ret, nr_opp, domain;
@@ -181,6 +204,7 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy)
struct device *cpu_dev;
struct scmi_data *priv;
struct cpufreq_frequency_table *freq_table;
+ struct scmi_cpufreq_driver_data *data = cpufreq_get_driver_data();
cpu_dev = get_cpu_device(policy->cpu);
if (!cpu_dev) {
@@ -294,6 +318,17 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy)
}
}
+ priv->limit_notify_nb.notifier_call = scmi_limit_notify_cb;
+ ret = data->handle->notify_ops->devm_event_notifier_register(data->sdev, SCMI_PROTOCOL_PERF,
+ SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED,
+ &domain,
+ &priv->limit_notify_nb);
+ if (ret)
+ dev_warn(cpu_dev,
+ "failed to register for limits change notifier for domain %d\n", domain);
+
+ priv->policy = policy;
+
return 0;
out_free_opp:
@@ -366,12 +401,21 @@ static int scmi_cpufreq_probe(struct scmi_device *sdev)
int ret;
struct device *dev = &sdev->dev;
const struct scmi_handle *handle;
+ struct scmi_cpufreq_driver_data *data;
handle = sdev->handle;
if (!handle)
return -ENODEV;
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->sdev = sdev;
+ data->handle = handle;
+ scmi_cpufreq_driver.driver_data = data;
+
perf_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_PERF, &ph);
if (IS_ERR(perf_ops))
return PTR_ERR(perf_ops);
--
2.34.1
The SCMI cpufreq driver doesn't require any additional signal
smoothing provided by arch_update_hw_pressure interface, export
cpufreq_update_pressure so that it can be called upon directly
instead.
Suggested-by: Lukasz Luba <[email protected]>
Signed-off-by: Sibi Sankar <[email protected]>
---
v4:
* Use EXPORT_SYMBOL_GPL instead. [Trilok]
drivers/cpufreq/cpufreq.c | 3 ++-
include/linux/cpufreq.h | 2 ++
2 files changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 1de8bd105934..656320554bb7 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -2590,7 +2590,7 @@ DEFINE_PER_CPU(unsigned long, cpufreq_pressure);
*
* Update the value of cpufreq pressure for all @cpus in the policy.
*/
-static void cpufreq_update_pressure(struct cpufreq_policy *policy)
+void cpufreq_update_pressure(struct cpufreq_policy *policy)
{
unsigned long max_capacity, capped_freq, pressure;
u32 max_freq;
@@ -2615,6 +2615,7 @@ static void cpufreq_update_pressure(struct cpufreq_policy *policy)
for_each_cpu(cpu, policy->related_cpus)
WRITE_ONCE(per_cpu(cpufreq_pressure, cpu), pressure);
}
+EXPORT_SYMBOL_GPL(cpufreq_update_pressure);
/**
* cpufreq_set_policy - Modify cpufreq policy parameters.
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 20f7e98ee8af..7410a1bade23 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -241,6 +241,7 @@ struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy);
void cpufreq_enable_fast_switch(struct cpufreq_policy *policy);
void cpufreq_disable_fast_switch(struct cpufreq_policy *policy);
bool has_target_index(void);
+void cpufreq_update_pressure(struct cpufreq_policy *policy);
DECLARE_PER_CPU(unsigned long, cpufreq_pressure);
static inline unsigned long cpufreq_get_pressure(int cpu)
@@ -270,6 +271,7 @@ static inline bool cpufreq_supports_freq_invariance(void)
}
static inline void disable_cpufreq(void) { }
static inline void cpufreq_update_limits(unsigned int cpu) { }
+static inline void cpufreq_update_pressure(struct cpufreq_policy *policy) { }
static inline unsigned long cpufreq_get_pressure(int cpu)
{
return 0;
--
2.34.1
On 3/28/24 07:41, Sibi Sankar wrote:
> Register for limit change notifications if supported and use the throttled
> frequency from the notification to apply HW pressure.
>
> Signed-off-by: Sibi Sankar <[email protected]>
> ---
>
> v4:
> * Use a interim variable to show the khz calc. [Lukasz]
> * Use driver_data to pass on the handle and scmi_dev instead of using
> global variables. Dropped Lukasz's Rb due to adding these minor
> changes.
>
> drivers/cpufreq/scmi-cpufreq.c | 44 ++++++++++++++++++++++++++++++++++
> 1 file changed, 44 insertions(+)
>
> diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c
> index 3b4f6bfb2f4c..d946b7a08258 100644
> --- a/drivers/cpufreq/scmi-cpufreq.c
> +++ b/drivers/cpufreq/scmi-cpufreq.c
> @@ -21,11 +21,18 @@
> #include <linux/types.h>
> #include <linux/units.h>
>
> +struct scmi_cpufreq_driver_data {
> + struct scmi_device *sdev;
> + const struct scmi_handle *handle;
> +};
> +
> struct scmi_data {
> int domain_id;
> int nr_opp;
> struct device *cpu_dev;
> + struct cpufreq_policy *policy;
> cpumask_var_t opp_shared_cpus;
> + struct notifier_block limit_notify_nb;
> };
>
> static struct scmi_protocol_handle *ph;
> @@ -174,6 +181,22 @@ static struct freq_attr *scmi_cpufreq_hw_attr[] = {
> NULL,
> };
>
> +static int scmi_limit_notify_cb(struct notifier_block *nb, unsigned long event, void *data)
> +{
> + struct scmi_data *priv = container_of(nb, struct scmi_data, limit_notify_nb);
> + struct scmi_perf_limits_report *limit_notify = data;
> + struct cpufreq_policy *policy = priv->policy;
> + unsigned int limit_freq_khz;
> +
> + limit_freq_khz = limit_notify->range_max_freq / HZ_PER_KHZ;
> +
> + policy->max = clamp(limit_freq_khz, policy->cpuinfo.min_freq, policy->cpuinfo.max_freq);
> +
> + cpufreq_update_pressure(policy);
> +
> + return NOTIFY_OK;
> +}
> +
> static int scmi_cpufreq_init(struct cpufreq_policy *policy)
> {
> int ret, nr_opp, domain;
> @@ -181,6 +204,7 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy)
> struct device *cpu_dev;
> struct scmi_data *priv;
> struct cpufreq_frequency_table *freq_table;
> + struct scmi_cpufreq_driver_data *data = cpufreq_get_driver_data();
>
> cpu_dev = get_cpu_device(policy->cpu);
> if (!cpu_dev) {
> @@ -294,6 +318,17 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy)
> }
> }
>
> + priv->limit_notify_nb.notifier_call = scmi_limit_notify_cb;
> + ret = data->handle->notify_ops->devm_event_notifier_register(data->sdev, SCMI_PROTOCOL_PERF,
> + SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED,
> + &domain,
> + &priv->limit_notify_nb);
> + if (ret)
> + dev_warn(cpu_dev,
> + "failed to register for limits change notifier for domain %d\n", domain);
> +
> + priv->policy = policy;
> +
> return 0;
>
> out_free_opp:
> @@ -366,12 +401,21 @@ static int scmi_cpufreq_probe(struct scmi_device *sdev)
> int ret;
> struct device *dev = &sdev->dev;
> const struct scmi_handle *handle;
> + struct scmi_cpufreq_driver_data *data;
>
> handle = sdev->handle;
>
> if (!handle)
> return -ENODEV;
>
> + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> + if (!data)
> + return -ENOMEM;
> +
> + data->sdev = sdev;
> + data->handle = handle;
> + scmi_cpufreq_driver.driver_data = data;
> +
> perf_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_PERF, &ph);
> if (IS_ERR(perf_ops))
> return PTR_ERR(perf_ops);
LGTM,
Reviewed-by: Lukasz Luba <[email protected]>
On Thu, Mar 28, 2024 at 01:11:31PM +0530, Sibi Sankar wrote:
> Register for limit change notifications if supported and use the throttled
> frequency from the notification to apply HW pressure.
>
Hi Sibi,
a bit late on this, sorry.
Just a couple of nitpicks down below.
> Signed-off-by: Sibi Sankar <[email protected]>
> ---
>
> v4:
> * Use a interim variable to show the khz calc. [Lukasz]
> * Use driver_data to pass on the handle and scmi_dev instead of using
> global variables. Dropped Lukasz's Rb due to adding these minor
> changes.
>
> drivers/cpufreq/scmi-cpufreq.c | 44 ++++++++++++++++++++++++++++++++++
> 1 file changed, 44 insertions(+)
>
> diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c
> index 3b4f6bfb2f4c..d946b7a08258 100644
> --- a/drivers/cpufreq/scmi-cpufreq.c
> +++ b/drivers/cpufreq/scmi-cpufreq.c
> @@ -21,11 +21,18 @@
> #include <linux/types.h>
> #include <linux/units.h>
>
> +struct scmi_cpufreq_driver_data {
> + struct scmi_device *sdev;
> + const struct scmi_handle *handle;
> +};
> +
> struct scmi_data {
> int domain_id;
> int nr_opp;
> struct device *cpu_dev;
> + struct cpufreq_policy *policy;
> cpumask_var_t opp_shared_cpus;
> + struct notifier_block limit_notify_nb;
> };
>
> static struct scmi_protocol_handle *ph;
> @@ -174,6 +181,22 @@ static struct freq_attr *scmi_cpufreq_hw_attr[] = {
> NULL,
> };
>
> +static int scmi_limit_notify_cb(struct notifier_block *nb, unsigned long event, void *data)
> +{
> + struct scmi_data *priv = container_of(nb, struct scmi_data, limit_notify_nb);
> + struct scmi_perf_limits_report *limit_notify = data;
> + struct cpufreq_policy *policy = priv->policy;
> + unsigned int limit_freq_khz;
> +
> + limit_freq_khz = limit_notify->range_max_freq / HZ_PER_KHZ;
> +
> + policy->max = clamp(limit_freq_khz, policy->cpuinfo.min_freq, policy->cpuinfo.max_freq);
> +
> + cpufreq_update_pressure(policy);
> +
> + return NOTIFY_OK;
> +}
> +
> static int scmi_cpufreq_init(struct cpufreq_policy *policy)
> {
> int ret, nr_opp, domain;
> @@ -181,6 +204,7 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy)
> struct device *cpu_dev;
> struct scmi_data *priv;
> struct cpufreq_frequency_table *freq_table;
> + struct scmi_cpufreq_driver_data *data = cpufreq_get_driver_data();
>
> cpu_dev = get_cpu_device(policy->cpu);
> if (!cpu_dev) {
> @@ -294,6 +318,17 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy)
> }
> }
>
> + priv->limit_notify_nb.notifier_call = scmi_limit_notify_cb;
> + ret = data->handle->notify_ops->devm_event_notifier_register(data->sdev, SCMI_PROTOCOL_PERF,
> + SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED,
> + &domain,
> + &priv->limit_notify_nb);
> + if (ret)
> + dev_warn(cpu_dev,
or &data->sdev->dev which refers to this driver ? which is more informational ? no strong opinion just a question...
> + "failed to register for limits change notifier for domain %d\n", domain);
> +
> + priv->policy = policy;
> +
> return 0;
>
> out_free_opp:
> @@ -366,12 +401,21 @@ static int scmi_cpufreq_probe(struct scmi_device *sdev)
> int ret;
> struct device *dev = &sdev->dev;
> const struct scmi_handle *handle;
> + struct scmi_cpufreq_driver_data *data;
>
> handle = sdev->handle;
^^^ ....
>
> if (!handle)
> return -ENODEV;
>
> + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> + if (!data)
> + return -ENOMEM;
> +
> + data->sdev = sdev;
> + data->handle = handle;
^^^ ... you dont need to pass around handle AND sdev really
since you can access the handle from sdev.
> + scmi_cpufreq_driver.driver_data = data;
This is slightly better, but, as said, does not solve the multi-instance issue...
..the scmi cpufreq driver remains a driver that works only if instantiated (probed)
once, given how the CPUFreq core handles cpufreq_driver registration itself...
..just a note about something to work on in the future...NOT a concern for this series.
In general,
LGTM.
Thanks,
Cristian
On Wed, May 01, 2024 at 09:21:30AM +0100, Cristian Marussi wrote:
> On Thu, Mar 28, 2024 at 01:11:31PM +0530, Sibi Sankar wrote:
> > Register for limit change notifications if supported and use the throttled
> > frequency from the notification to apply HW pressure.
> >
>
> Hi Sibi,
>
> a bit late on this, sorry.
>
..forgot the tag :P
> Just a couple of nitpicks down below.
[snip]
> In general,
>
> LGTM.
>
Reviewed-by: Cristian Marussi <[email protected]>
Thanks,
Cristian