Re: [PATCH v2 4/4] PM / AVS: rockchip-cpu-avs: add driver handling Rockchip cpu avs

From: Viresh Kumar
Date: Mon Aug 29 2016 - 02:08:28 EST


On 18-08-16, 16:52, Finlye Xiao wrote:
> +static int rockchip_adjust_opp_table(struct device *cpu_dev,
> + struct cpufreq_frequency_table *table,
> + int volt)
> +{
> + struct opp_table *opp_table;
> + struct cpufreq_frequency_table *pos;
> + struct dev_pm_opp *opp;
> +
> + if (!volt)
> + return 0;
> +
> + rcu_read_lock();
> +
> + opp_table = _find_opp_table(cpu_dev);
> + if (IS_ERR(opp_table)) {
> + rcu_read_unlock();
> + return PTR_ERR(opp_table);
> + }
> +
> + cpufreq_for_each_valid_entry(pos, table) {
> + opp = dev_pm_opp_find_freq_exact(cpu_dev, pos->frequency * 1000,
> + true);
> + if (IS_ERR(opp))
> + continue;
> +
> + opp->u_volt += volt;
> + opp->u_volt_min += volt;
> + opp->u_volt_max += volt;
> + }
> +
> + rcu_read_unlock();
> +
> + return 0;
> +}

I wouldn't prefer altering the opp tables from individual drivers at all. At the
least, it should be done via some helpers exposed by the core.

But before that I would like to hear from Stephen a bit as I recall he was also
working on something similar.

--
viresh