[PATCH v3 1/2] cpufreq / OPP: Allow boost frequency to be looked up from device tree

[Viresh Kumar]

On 14 May 2014 06:32, Thomas Abraham <ta.omasab at gmail.com> wrote:
> From: Thomas Abraham <thomas.ab at samsung.com>
>
> Commit 6f19efc0 ("cpufreq: Add boost frequency support in core") adds
> support for CPU boost mode. This patch adds support for finding available
> boost frequencies from device tree and marking them as usable in boost mode.
>
> Cc: Nishanth Menon <nm at ti.com>
> Cc: Lukasz Majewski <l.majewski at samsung.com>
> Signed-off-by: Thomas Abraham <thomas.ab at samsung.com>
> ---
>  drivers/cpufreq/cpufreq_opp.c |   39 +++++++++++++++++++++++++++++++++++++++
>  1 files changed, 39 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/cpufreq/cpufreq_opp.c b/drivers/cpufreq/cpufreq_opp.c
> index c0c6f4a..e3c97f3 100644
> --- a/drivers/cpufreq/cpufreq_opp.c
> +++ b/drivers/cpufreq/cpufreq_opp.c
> @@ -19,6 +19,7 @@
>  #include <linux/pm_opp.h>
>  #include <linux/rcupdate.h>
>  #include <linux/slab.h>
> +#include <linux/of.h>
>
>  /**
>   * dev_pm_opp_init_cpufreq_table() - create a cpufreq table for a device
> @@ -51,6 +52,10 @@ int dev_pm_opp_init_cpufreq_table(struct device *dev,
>         struct cpufreq_frequency_table *freq_table = NULL;
>         int i, max_opps, ret = 0;
>         unsigned long rate;
> +#ifdef CONFIG_CPU_FREQ_BOOST_SW
> +       int j, len;
> +       u32 *boost_freqs = NULL;
> +#endif
>
>         rcu_read_lock();
>
> @@ -82,6 +87,40 @@ int dev_pm_opp_init_cpufreq_table(struct device *dev,
>
>         *table = &freq_table[0];
>
> +#ifdef CONFIG_CPU_FREQ_BOOST_SW
> +       if (of_find_property(dev->of_node, "boost-frequency", &len)) {

Does this mean another block inside the cpu node ? Like this: ?

cpu at 0 {
        compatible = "arm,cortex-a9";
        reg = <0>;
        next-level-cache = <&L2>;
        operating-points = <
                /* kHz    uV */
                792000  1100000
                396000  950000
                198000  850000
        >;
        boost-frequency = <
                792000
                198000
        >;
};

I think it we might better add another field in the opp block as these
OPPs are rather boost one..

@Rob/Rafael: Opinion please ..

> +               if (len == 0 || (len & (sizeof(u32) - 1)) != 0) {
> +                       dev_err(dev, "%s: invalid boost frequency\n", __func__);
> +                       ret = -EINVAL;
> +                       goto out;
> +               }
> +
> +               boost_freqs = kzalloc(len, GFP_KERNEL);
> +               if (!boost_freqs) {
> +                       dev_warn(dev, "%s: no memory for boost freq table\n",
> +                                       __func__);
> +                       ret = -ENOMEM;
> +                       goto out;
> +               }
> +               of_property_read_u32_array(dev->of_node, "boost-frequency",
> +                       boost_freqs, len / sizeof(u32));
> +       }
> +
> +       for (j = 0; j < len / sizeof(u32) && boost_freqs; j++) {

Why is this present outside of above if {} ? as boost_freqs is guaranteed to
be NULL without that.

> +               for (i = 0; freq_table[i].frequency != CPUFREQ_TABLE_END; i++) {
> +                       if (boost_freqs[j] == freq_table[i].frequency) {

Use cpufreq_frequency_table_get_index() instead.

> +                               freq_table[i].flags |= CPUFREQ_BOOST_FREQ;
> +                               break;
> +                       }
> +               }
> +               if (freq_table[i].frequency == CPUFREQ_TABLE_END)
> +                       pr_err("%s: invalid boost frequency %d\n",
> +                               __func__, boost_freqs[j]);
> +       }
> +
> +       kfree(boost_freqs);
> +#endif
> +
>  out:
>         rcu_read_unlock();
>         if (ret)
> --
> 1.7.4.4
>