diff mbox series

[V5,4/7] cpufreq: Add a notification message that the highest perf has changed

Message ID 20230905015116.2268926-5-li.meng@amd.com
State Superseded
Headers show
Series amd-pstate preferred core | expand

Commit Message

Meng, Li (Jassmine) Sept. 5, 2023, 1:51 a.m. UTC
ACPI 6.5 section 8.4.6.1.1.1 specifies that Notify event 0x85 can be
emmitted to cause the the OSPM to re-evaluate the highest performance
register. Add support for this event.

Signed-off-by: Meng Li <li.meng@amd.com>
Link: https://uefi.org/specs/ACPI/6.5/08_Processor_Configuration_and_Control.html?highlight=cppc#cpc-continuous-performance-control
---
 drivers/acpi/processor_driver.c |  6 ++++++
 drivers/cpufreq/cpufreq.c       | 13 +++++++++++++
 include/linux/cpufreq.h         |  5 +++++
 3 files changed, 24 insertions(+)

Comments

Peter Zijlstra Sept. 8, 2023, 1:19 p.m. UTC | #1
On Tue, Sep 05, 2023 at 09:51:13AM +0800, Meng Li wrote:
> ACPI 6.5 section 8.4.6.1.1.1 specifies that Notify event 0x85 can be
> emmitted to cause the the OSPM to re-evaluate the highest performance
> register. Add support for this event.
> 
> Signed-off-by: Meng Li <li.meng@amd.com>
> Link: https://uefi.org/specs/ACPI/6.5/08_Processor_Configuration_and_Control.html?highlight=cppc#cpc-continuous-performance-control

Does uefi.org guarantee this is a stable link?
Peter Zijlstra Sept. 8, 2023, 1:24 p.m. UTC | #2
On Tue, Sep 05, 2023 at 09:51:13AM +0800, Meng Li wrote:
> ACPI 6.5 section 8.4.6.1.1.1 specifies that Notify event 0x85 can be
> emmitted to cause the the OSPM to re-evaluate the highest performance
> register. Add support for this event.
> 
> Signed-off-by: Meng Li <li.meng@amd.com>
> Link: https://uefi.org/specs/ACPI/6.5/08_Processor_Configuration_and_Control.html?highlight=cppc#cpc-continuous-performance-control
> ---
>  drivers/acpi/processor_driver.c |  6 ++++++
>  drivers/cpufreq/cpufreq.c       | 13 +++++++++++++
>  include/linux/cpufreq.h         |  5 +++++
>  3 files changed, 24 insertions(+)
> 
> diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
> index 4bd16b3f0781..29b2fb68a35d 100644
> --- a/drivers/acpi/processor_driver.c
> +++ b/drivers/acpi/processor_driver.c
> @@ -27,6 +27,7 @@
>  #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
>  #define ACPI_PROCESSOR_NOTIFY_POWER	0x81
>  #define ACPI_PROCESSOR_NOTIFY_THROTTLING	0x82
> +#define ACPI_PROCESSOR_NOTIFY_HIGEST_PERF_CHANGED	0x85
>  
>  MODULE_AUTHOR("Paul Diefenbaugh");
>  MODULE_DESCRIPTION("ACPI Processor Driver");
> @@ -83,6 +84,11 @@ static void acpi_processor_notify(acpi_handle handle, u32 event, void *data)
>  		acpi_bus_generate_netlink_event(device->pnp.device_class,
>  						  dev_name(&device->dev), event, 0);
>  		break;
> +	case ACPI_PROCESSOR_NOTIFY_HIGEST_PERF_CHANGED:
> +		cpufreq_update_highest_perf(pr->id);
> +		acpi_bus_generate_netlink_event(device->pnp.device_class,
> +						  dev_name(&device->dev), event, 0);
> +		break;
>  	default:
>  		acpi_handle_debug(handle, "Unsupported event [0x%x]\n", event);
>  		break;

I've obviously not read the link, but the above seems to suggest that
every CPU that has its limits changed gets the 'interrupt' ?
Meng, Li (Jassmine) Sept. 11, 2023, 8:43 a.m. UTC | #3
[AMD Official Use Only - General]

Hi Peter:

> -----Original Message-----
> From: Peter Zijlstra <peterz@infradead.org>
> Sent: Friday, September 8, 2023 9:24 PM
> To: Meng, Li (Jassmine) <Li.Meng@amd.com>
> Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>; Huang, Ray
> <Ray.Huang@amd.com>; linux-pm@vger.kernel.org; linux-
> kernel@vger.kernel.org; x86@kernel.org; linux-acpi@vger.kernel.org; Shuah
> Khan <skhan@linuxfoundation.org>; linux-kselftest@vger.kernel.org;
> Fontenot, Nathan <Nathan.Fontenot@amd.com>; Sharma, Deepak
> <Deepak.Sharma@amd.com>; Deucher, Alexander
> <Alexander.Deucher@amd.com>; Limonciello, Mario
> <Mario.Limonciello@amd.com>; Huang, Shimmer
> <Shimmer.Huang@amd.com>; Yuan, Perry <Perry.Yuan@amd.com>; Du,
> Xiaojian <Xiaojian.Du@amd.com>; Viresh Kumar <viresh.kumar@linaro.org>;
> Borislav Petkov <bp@alien8.de>
> Subject: Re: [PATCH V5 4/7] cpufreq: Add a notification message that the
> highest perf has changed
>
> Caution: This message originated from an External Source. Use proper
> caution when opening attachments, clicking links, or responding.
>
>
> On Tue, Sep 05, 2023 at 09:51:13AM +0800, Meng Li wrote:
> > ACPI 6.5 section 8.4.6.1.1.1 specifies that Notify event 0x85 can be
> > emmitted to cause the the OSPM to re-evaluate the highest performance
> > register. Add support for this event.
> >
> > Signed-off-by: Meng Li <li.meng@amd.com>
> > Link:
> > https://uefi.org/specs/ACPI/6.5/08_Processor_Configuration_and_Control
> > .html?highlight=cppc#cpc-continuous-performance-control
> > ---
> >  drivers/acpi/processor_driver.c |  6 ++++++
> >  drivers/cpufreq/cpufreq.c       | 13 +++++++++++++
> >  include/linux/cpufreq.h         |  5 +++++
> >  3 files changed, 24 insertions(+)
> >
> > diff --git a/drivers/acpi/processor_driver.c
> > b/drivers/acpi/processor_driver.c index 4bd16b3f0781..29b2fb68a35d
> > 100644
> > --- a/drivers/acpi/processor_driver.c
> > +++ b/drivers/acpi/processor_driver.c
> > @@ -27,6 +27,7 @@
> >  #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80  #define
> > ACPI_PROCESSOR_NOTIFY_POWER  0x81
> >  #define ACPI_PROCESSOR_NOTIFY_THROTTLING     0x82
> > +#define ACPI_PROCESSOR_NOTIFY_HIGEST_PERF_CHANGED    0x85
> >
> >  MODULE_AUTHOR("Paul Diefenbaugh");
> >  MODULE_DESCRIPTION("ACPI Processor Driver"); @@ -83,6 +84,11 @@
> > static void acpi_processor_notify(acpi_handle handle, u32 event, void
> *data)
> >               acpi_bus_generate_netlink_event(device->pnp.device_class,
> >                                                 dev_name(&device->dev), event, 0);
> >               break;
> > +     case ACPI_PROCESSOR_NOTIFY_HIGEST_PERF_CHANGED:
> > +             cpufreq_update_highest_perf(pr->id);
> > +             acpi_bus_generate_netlink_event(device->pnp.device_class,
> > +                                               dev_name(&device->dev), event, 0);
> > +             break;
> >       default:
> >               acpi_handle_debug(handle, "Unsupported event [0x%x]\n", event);
> >               break;
>
> I've obviously not read the link, but the above seems to suggest that every
> CPU that has its limits changed gets the 'interrupt' ?
[Meng, Li (Jassmine)]
Yes.
I will modify the link to https://uefi.org/specs/ACPI/6.5/05_ACPI_Software_Programming_Model.html#processor-device-notification-values
diff mbox series

Patch

diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
index 4bd16b3f0781..29b2fb68a35d 100644
--- a/drivers/acpi/processor_driver.c
+++ b/drivers/acpi/processor_driver.c
@@ -27,6 +27,7 @@ 
 #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
 #define ACPI_PROCESSOR_NOTIFY_POWER	0x81
 #define ACPI_PROCESSOR_NOTIFY_THROTTLING	0x82
+#define ACPI_PROCESSOR_NOTIFY_HIGEST_PERF_CHANGED	0x85
 
 MODULE_AUTHOR("Paul Diefenbaugh");
 MODULE_DESCRIPTION("ACPI Processor Driver");
@@ -83,6 +84,11 @@  static void acpi_processor_notify(acpi_handle handle, u32 event, void *data)
 		acpi_bus_generate_netlink_event(device->pnp.device_class,
 						  dev_name(&device->dev), event, 0);
 		break;
+	case ACPI_PROCESSOR_NOTIFY_HIGEST_PERF_CHANGED:
+		cpufreq_update_highest_perf(pr->id);
+		acpi_bus_generate_netlink_event(device->pnp.device_class,
+						  dev_name(&device->dev), event, 0);
+		break;
 	default:
 		acpi_handle_debug(handle, "Unsupported event [0x%x]\n", event);
 		break;
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 60ed89000e82..4ada787ff105 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -2718,6 +2718,19 @@  void cpufreq_update_limits(unsigned int cpu)
 }
 EXPORT_SYMBOL_GPL(cpufreq_update_limits);
 
+/**
+ * cpufreq_update_highest_perf - Update highest performance for a given CPU.
+ * @cpu: CPU to update the highest performance for.
+ *
+ * Invoke the driver's ->update_highest_perf callback if present
+ */
+void cpufreq_update_highest_perf(unsigned int cpu)
+{
+	if (cpufreq_driver->update_highest_perf)
+		cpufreq_driver->update_highest_perf(cpu);
+}
+EXPORT_SYMBOL_GPL(cpufreq_update_highest_perf);
+
 /*********************************************************************
  *               BOOST						     *
  *********************************************************************/
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 71d186d6933a..1cc1241fb698 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -235,6 +235,7 @@  int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu);
 void refresh_frequency_limits(struct cpufreq_policy *policy);
 void cpufreq_update_policy(unsigned int cpu);
 void cpufreq_update_limits(unsigned int cpu);
+void cpufreq_update_highest_perf(unsigned int cpu);
 bool have_governor_per_policy(void);
 bool cpufreq_supports_freq_invariance(void);
 struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy);
@@ -263,6 +264,7 @@  static inline bool cpufreq_supports_freq_invariance(void)
 	return false;
 }
 static inline void disable_cpufreq(void) { }
+static inline void cpufreq_update_highest_perf(unsigned int cpu) { }
 #endif
 
 #ifdef CONFIG_CPU_FREQ_STAT
@@ -380,6 +382,9 @@  struct cpufreq_driver {
 	/* Called to update policy limits on firmware notifications. */
 	void		(*update_limits)(unsigned int cpu);
 
+	/* Called to update highest performance on firmware notifications. */
+	void		(*update_highest_perf)(unsigned int cpu);
+
 	/* optional */
 	int		(*bios_limit)(int cpu, unsigned int *limit);