Re: [PATCH v4 1/6] cpufreq: make scaling_boost_freqs sysfs attr available when boost is enabled

From: Bartlomiej Zolnierkiewicz
Date: Fri Aug 07 2015 - 06:35:51 EST



Hi,

On Friday, August 07, 2015 09:11:28 AM Viresh Kumar wrote:
> Hi,
>
> I would suggest you sending such patches as reply to the earlier
> threads only, instead of a new chain. This will save your time.

Please explain it more. This patch needs to be first for cpufreq-dt
switch to be complete. scaling_boost_freqs is available currently
for exynos-cpufreq users when boost is enabled and ideally we would
like it to be available immediately after the switch to cpufreq-dt.

> For example, you will need to resend other patches unnecessarily if I
> NAK this patch :)
>
> On 06-08-15, 15:41, Bartlomiej Zolnierkiewicz wrote:
> > Add cpufreq_boost_enabled_generic_attr table and use it in
> > cpufreq-dt driver instead of cpufreq_generic_attr one when
> > boost support is enabled. As a result scaling_boost_freqs
> > sysfs attribute is available when cpufreq-dt driver is
> > used and boost support is enabled.
> >
> > Cc: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> > Cc: Thomas Abraham <thomas.ab@xxxxxxxxxxx>
> > Cc: Javier Martinez Canillas <javier@xxxxxxxxxxxxxxx>
> > Cc: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>
> > Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
> > ---
> > drivers/cpufreq/cpufreq-dt.c | 3 +++
> > drivers/cpufreq/freq_table.c | 7 +++++++
> > include/linux/cpufreq.h | 1 +
> > 3 files changed, 11 insertions(+)
> >
> > diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c
> > index b9259ab..7b091c0 100644
> > --- a/drivers/cpufreq/cpufreq-dt.c
> > +++ b/drivers/cpufreq/cpufreq-dt.c
> > @@ -182,6 +182,8 @@ try_again:
> > return ret;
> > }
> >
> > +static struct cpufreq_driver dt_cpufreq_driver;
> > +
> > static int cpufreq_init(struct cpufreq_policy *policy)
> > {
> > struct cpufreq_frequency_table *freq_table;
> > @@ -336,6 +338,7 @@ static int cpufreq_init(struct cpufreq_policy *policy)
> > ret = cpufreq_enable_boost_support();
> > if (ret)
> > goto out_free_cpufreq_table;
> > + dt_cpufreq_driver.attr = cpufreq_boost_enabled_generic_attr;
> > }
> >
> > policy->cpuinfo.transition_latency = transition_latency;
> > diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c
> > index a8f1daf..5a00a09 100644
> > --- a/drivers/cpufreq/freq_table.c
> > +++ b/drivers/cpufreq/freq_table.c
> > @@ -300,6 +300,13 @@ struct freq_attr *cpufreq_generic_attr[] = {
> > };
> > EXPORT_SYMBOL_GPL(cpufreq_generic_attr);
> >
> > +struct freq_attr *cpufreq_boost_enabled_generic_attr[] = {
> > + &cpufreq_freq_attr_scaling_available_freqs,
> > + &cpufreq_freq_attr_scaling_boost_freqs,
> > + NULL,
> > +};
> > +EXPORT_SYMBOL_GPL(cpufreq_boost_enabled_generic_attr);
>
> This isn't scalable. We can't create a new generic structure every time
> a entry comes in. Rather we should leave the generic attr for

boost entry is rather generic one so I imagine that other cpufreq
drivers that add support for boost would also like to use it.

Anyway since there are no such drivers currently I agree that
making a new generic structure may be premature and I will re-do
this patch according to your request.

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

> cpufreq-dt and do something like this in the cpufreq-dt driver (And
> that patch should rather go via cpufreq tree and not ARM SoC)..
>
> diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c
> index a5b6a854661f..e229258ad791 100644
> --- a/drivers/cpufreq/cpufreq-dt.c
> +++ b/drivers/cpufreq/cpufreq-dt.c
> @@ -36,6 +36,12 @@ struct private_data {
> unsigned int voltage_tolerance; /* in percentage */
> };
>
> +static struct freq_attr *cpufreq_dt_attr[] = {
> + &cpufreq_freq_attr_scaling_available_freqs,
> + NULL, /* Extra space for boost-attr if required */
> + NULL,
> +};
> +
> static int set_target(struct cpufreq_policy *policy, unsigned int index)
> {
> struct dev_pm_opp *opp;
> @@ -337,6 +343,7 @@ static int cpufreq_init(struct cpufreq_policy *policy)
> ret = cpufreq_enable_boost_support();
> if (ret)
> goto out_free_cpufreq_table;
> + cpufreq_dt_attr[1] = &cpufreq_freq_attr_scaling_boost_freqs;
> }
>
> policy->cpuinfo.transition_latency = transition_latency;
> @@ -412,7 +419,7 @@ static struct cpufreq_driver dt_cpufreq_driver = {
> .exit = cpufreq_exit,
> .ready = cpufreq_ready,
> .name = "cpufreq-dt",
> - .attr = cpufreq_generic_attr,
> + .attr = cpufreq_dt_attr,
> };
>
> static int dt_cpufreq_probe(struct platform_device *pdev)

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