Re: [PATCH 2/7] cpufreq: dt: Register an Energy Model

From: Viresh Kumar
Date: Tue Jan 29 2019 - 00:30:48 EST


On 28-01-19, 16:55, Quentin Perret wrote:
> Now that PM_OPP provides a helper function to estimate the power
> consumed by CPUs, make sure to try and register an Energy Model (EM)
> from cpufreq-dt, hence ensuring interested subsystems (the task
> scheduler, for example) can make use of that information when available.
>
> Signed-off-by: Quentin Perret <quentin.perret@xxxxxxx>
> ---
> drivers/cpufreq/cpufreq-dt.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c
> index e58bfcb1169e..7556e07e7a9f 100644
> --- a/drivers/cpufreq/cpufreq-dt.c
> +++ b/drivers/cpufreq/cpufreq-dt.c
> @@ -16,6 +16,7 @@
> #include <linux/cpu_cooling.h>
> #include <linux/cpufreq.h>
> #include <linux/cpumask.h>
> +#include <linux/energy_model.h>
> #include <linux/err.h>
> #include <linux/module.h>
> #include <linux/of.h>
> @@ -152,6 +153,7 @@ static int resources_available(void)
>
> static int cpufreq_init(struct cpufreq_policy *policy)
> {
> + struct em_data_callback em_cb = EM_DATA_CB(of_dev_pm_opp_get_cpu_power);

Hmm, so all the earlier comments regarding prototype of this routine are invalid
because of this.

> struct cpufreq_frequency_table *freq_table;
> struct opp_table *opp_table = NULL;
> struct private_data *priv;
> @@ -160,7 +162,7 @@ static int cpufreq_init(struct cpufreq_policy *policy)
> unsigned int transition_latency;
> bool fallback = false;
> const char *name;
> - int ret;
> + int ret, nr_opp;
>
> cpu_dev = get_cpu_device(policy->cpu);
> if (!cpu_dev) {
> @@ -237,6 +239,7 @@ static int cpufreq_init(struct cpufreq_policy *policy)
> ret = -EPROBE_DEFER;
> goto out_free_opp;
> }
> + nr_opp = ret;

Instead use nr_opp instead of ret while calling dev_pm_opp_get_opp_count().

>
> if (fallback) {
> cpumask_setall(policy->cpus);
> @@ -280,6 +283,8 @@ static int cpufreq_init(struct cpufreq_policy *policy)
> policy->cpuinfo.transition_latency = transition_latency;
> policy->dvfs_possible_from_any_cpu = true;
>
> + em_register_perf_domain(policy->cpus, nr_opp, &em_cb);
> +
> return 0;
>
> out_free_cpufreq_table:
> --
> 2.20.1

--
viresh