public inbox for linux-pm@vger.kernel.org
 help / color / mirror / Atom feed
* [PATCH] pcc-cpufreq driver update default value of cpuinfo_transition_latency
@ 2015-11-19 15:29 Jacob Tanenbaum
  2015-11-20  1:58 ` Viresh Kumar
  0 siblings, 1 reply; 3+ messages in thread
From: Jacob Tanenbaum @ 2015-11-19 15:29 UTC (permalink / raw)
  To: linux-pm; +Cc: corbet, rjw, viresh.kumar, prarit, Jacob Tanenbaum

The cpufreq documentation specifies

policy->cpuinfo.transition_latency   the time it takes on this CPU to
                                switch between two frequencies in
                                nanoseconds (if appropriate, else
                                specify CPUFREQ_ETERNAL)

currently pcc-cpufreq does not expose the value and sets it to zero. I
changed the pcc-cpufreq driver and it's documentation to conform to the
default value specified in Documentation/cpu-freq/cpu-drivers.txt

Signed-off-by: Jacob Tanenbaum <jtanenba@redhat.com>
---
 Documentation/cpu-freq/pcc-cpufreq.txt | 4 ++--
 drivers/cpufreq/pcc-cpufreq.c          | 2 ++
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/Documentation/cpu-freq/pcc-cpufreq.txt b/Documentation/cpu-freq/pcc-cpufreq.txt
index 9e3c3b3..0a94224 100644
--- a/Documentation/cpu-freq/pcc-cpufreq.txt
+++ b/Documentation/cpu-freq/pcc-cpufreq.txt
@@ -159,8 +159,8 @@ to be strictly associated with a P-state.
 
 2.2 cpuinfo_transition_latency:
 -------------------------------
-The cpuinfo_transition_latency field is 0. The PCC specification does
-not include a field to expose this value currently.
+The cpuinfo_transition_latency field is CPUFREQ_ETERNAL. The PCC specification
+does not include a field to expose this value currently.
 
 2.3 cpuinfo_cur_freq:
 ---------------------
diff --git a/drivers/cpufreq/pcc-cpufreq.c b/drivers/cpufreq/pcc-cpufreq.c
index 2a0d589..808a320 100644
--- a/drivers/cpufreq/pcc-cpufreq.c
+++ b/drivers/cpufreq/pcc-cpufreq.c
@@ -555,6 +555,8 @@ static int pcc_cpufreq_cpu_init(struct cpufreq_policy *policy)
 	policy->min = policy->cpuinfo.min_freq =
 		ioread32(&pcch_hdr->minimum_frequency) * 1000;
 
+	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
+
 	pr_debug("init: policy->max is %d, policy->min is %d\n",
 		policy->max, policy->min);
 out:
-- 
2.4.3


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] pcc-cpufreq driver update default value of cpuinfo_transition_latency
  2015-11-19 15:29 [PATCH] pcc-cpufreq driver update default value of cpuinfo_transition_latency Jacob Tanenbaum
@ 2015-11-20  1:58 ` Viresh Kumar
  2015-12-14 23:57   ` Rafael J. Wysocki
  0 siblings, 1 reply; 3+ messages in thread
From: Viresh Kumar @ 2015-11-20  1:58 UTC (permalink / raw)
  To: Jacob Tanenbaum; +Cc: linux-pm, corbet, rjw, prarit

On 19-11-15, 10:29, Jacob Tanenbaum wrote:
> The cpufreq documentation specifies
> 
> policy->cpuinfo.transition_latency   the time it takes on this CPU to
>                                 switch between two frequencies in
>                                 nanoseconds (if appropriate, else
>                                 specify CPUFREQ_ETERNAL)
> 
> currently pcc-cpufreq does not expose the value and sets it to zero. I
> changed the pcc-cpufreq driver and it's documentation to conform to the
> default value specified in Documentation/cpu-freq/cpu-drivers.txt
> 
> Signed-off-by: Jacob Tanenbaum <jtanenba@redhat.com>
> ---
>  Documentation/cpu-freq/pcc-cpufreq.txt | 4 ++--
>  drivers/cpufreq/pcc-cpufreq.c          | 2 ++
>  2 files changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/cpu-freq/pcc-cpufreq.txt b/Documentation/cpu-freq/pcc-cpufreq.txt
> index 9e3c3b3..0a94224 100644
> --- a/Documentation/cpu-freq/pcc-cpufreq.txt
> +++ b/Documentation/cpu-freq/pcc-cpufreq.txt
> @@ -159,8 +159,8 @@ to be strictly associated with a P-state.
>  
>  2.2 cpuinfo_transition_latency:
>  -------------------------------
> -The cpuinfo_transition_latency field is 0. The PCC specification does
> -not include a field to expose this value currently.
> +The cpuinfo_transition_latency field is CPUFREQ_ETERNAL. The PCC specification
> +does not include a field to expose this value currently.
>  
>  2.3 cpuinfo_cur_freq:
>  ---------------------
> diff --git a/drivers/cpufreq/pcc-cpufreq.c b/drivers/cpufreq/pcc-cpufreq.c
> index 2a0d589..808a320 100644
> --- a/drivers/cpufreq/pcc-cpufreq.c
> +++ b/drivers/cpufreq/pcc-cpufreq.c
> @@ -555,6 +555,8 @@ static int pcc_cpufreq_cpu_init(struct cpufreq_policy *policy)
>  	policy->min = policy->cpuinfo.min_freq =
>  		ioread32(&pcch_hdr->minimum_frequency) * 1000;
>  
> +	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
> +
>  	pr_debug("init: policy->max is %d, policy->min is %d\n",
>  		policy->max, policy->min);
>  out:

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

-- 
viresh

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] pcc-cpufreq driver update default value of cpuinfo_transition_latency
  2015-11-20  1:58 ` Viresh Kumar
@ 2015-12-14 23:57   ` Rafael J. Wysocki
  0 siblings, 0 replies; 3+ messages in thread
From: Rafael J. Wysocki @ 2015-12-14 23:57 UTC (permalink / raw)
  To: Viresh Kumar, Jacob Tanenbaum; +Cc: linux-pm, corbet, prarit

On Friday, November 20, 2015 07:28:20 AM Viresh Kumar wrote:
> On 19-11-15, 10:29, Jacob Tanenbaum wrote:
> > The cpufreq documentation specifies
> > 
> > policy->cpuinfo.transition_latency   the time it takes on this CPU to
> >                                 switch between two frequencies in
> >                                 nanoseconds (if appropriate, else
> >                                 specify CPUFREQ_ETERNAL)
> > 
> > currently pcc-cpufreq does not expose the value and sets it to zero. I
> > changed the pcc-cpufreq driver and it's documentation to conform to the
> > default value specified in Documentation/cpu-freq/cpu-drivers.txt
> > 
> > Signed-off-by: Jacob Tanenbaum <jtanenba@redhat.com>
> > ---
> >  Documentation/cpu-freq/pcc-cpufreq.txt | 4 ++--
> >  drivers/cpufreq/pcc-cpufreq.c          | 2 ++
> >  2 files changed, 4 insertions(+), 2 deletions(-)
> > 
> > diff --git a/Documentation/cpu-freq/pcc-cpufreq.txt b/Documentation/cpu-freq/pcc-cpufreq.txt
> > index 9e3c3b3..0a94224 100644
> > --- a/Documentation/cpu-freq/pcc-cpufreq.txt
> > +++ b/Documentation/cpu-freq/pcc-cpufreq.txt
> > @@ -159,8 +159,8 @@ to be strictly associated with a P-state.
> >  
> >  2.2 cpuinfo_transition_latency:
> >  -------------------------------
> > -The cpuinfo_transition_latency field is 0. The PCC specification does
> > -not include a field to expose this value currently.
> > +The cpuinfo_transition_latency field is CPUFREQ_ETERNAL. The PCC specification
> > +does not include a field to expose this value currently.
> >  
> >  2.3 cpuinfo_cur_freq:
> >  ---------------------
> > diff --git a/drivers/cpufreq/pcc-cpufreq.c b/drivers/cpufreq/pcc-cpufreq.c
> > index 2a0d589..808a320 100644
> > --- a/drivers/cpufreq/pcc-cpufreq.c
> > +++ b/drivers/cpufreq/pcc-cpufreq.c
> > @@ -555,6 +555,8 @@ static int pcc_cpufreq_cpu_init(struct cpufreq_policy *policy)
> >  	policy->min = policy->cpuinfo.min_freq =
> >  		ioread32(&pcch_hdr->minimum_frequency) * 1000;
> >  
> > +	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
> > +
> >  	pr_debug("init: policy->max is %d, policy->min is %d\n",
> >  		policy->max, policy->min);
> >  out:
> 
> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

Applied, thanks!

Rafael


^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2015-12-14 23:27 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2015-11-19 15:29 [PATCH] pcc-cpufreq driver update default value of cpuinfo_transition_latency Jacob Tanenbaum
2015-11-20  1:58 ` Viresh Kumar
2015-12-14 23:57   ` Rafael J. Wysocki

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox