On Thu, 2022-05-05 at 19:52 +0800, Rex-BC Chen wrote: > From this opp notifier, cpufreq should listen to opp notification and > do Hello Viresh, There is still ">" in this patch... I think the root cause could be the "From" word in the beginning of this message. I will not use "From" in next version.. BRs, Rex > proper actions when receiving events of disable and voltage > adjustment. > > One of the user for this opp notifier is MediaTek SVS. > The MediaTek Smart Voltage Scaling (SVS) is a hardware which > calculates > suitable SVS bank voltages to OPP voltage table. > > Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@xxxxxxxxxxxx> > Signed-off-by: Jia-Wei Chang <jia-wei.chang@xxxxxxxxxxxx> > Signed-off-by: Rex-BC Chen <rex-bc.chen@xxxxxxxxxxxx> > Reviewed-by: AngeloGioacchino Del Regno < > angelogioacchino.delregno@xxxxxxxxxxxxx> > --- > drivers/cpufreq/mediatek-cpufreq.c | 91 +++++++++++++++++++++++++++- > -- > 1 file changed, 83 insertions(+), 8 deletions(-) > > diff --git a/drivers/cpufreq/mediatek-cpufreq.c > b/drivers/cpufreq/mediatek-cpufreq.c > index fe205eca657d..06d80ee06bbf 100644 > --- a/drivers/cpufreq/mediatek-cpufreq.c > +++ b/drivers/cpufreq/mediatek-cpufreq.c > @@ -46,6 +46,11 @@ struct mtk_cpu_dvfs_info { > int intermediate_voltage; > bool need_voltage_tracking; > int pre_vproc; > + /* Avoid race condition for regulators between notify and > policy */ > + struct mutex reg_lock; > + struct notifier_block opp_nb; > + unsigned int opp_cpu; > + unsigned long opp_freq; > const struct mtk_cpufreq_platform_data *soc_data; > int vtrack_max; > }; > @@ -182,6 +187,8 @@ static int mtk_cpufreq_set_target(struct > cpufreq_policy *policy, > > pre_freq_hz = clk_get_rate(cpu_clk); > > + mutex_lock(&info->reg_lock); > + > if (unlikely(info->pre_vproc <= 0)) > pre_vproc = regulator_get_voltage(info->proc_reg); > else > @@ -214,7 +221,7 @@ static int mtk_cpufreq_set_target(struct > cpufreq_policy *policy, > dev_err(cpu_dev, > "cpu%d: failed to scale up voltage!\n", > policy->cpu); > mtk_cpufreq_set_voltage(info, pre_vproc); > - return ret; > + goto out; > } > } > > @@ -224,8 +231,7 @@ static int mtk_cpufreq_set_target(struct > cpufreq_policy *policy, > dev_err(cpu_dev, > "cpu%d: failed to re-parent cpu clock!\n", > policy->cpu); > mtk_cpufreq_set_voltage(info, pre_vproc); > - WARN_ON(1); > - return ret; > + goto out; > } > > /* Set the original PLL to target rate. */ > @@ -235,7 +241,7 @@ static int mtk_cpufreq_set_target(struct > cpufreq_policy *policy, > "cpu%d: failed to scale cpu clock rate!\n", > policy->cpu); > clk_set_parent(cpu_clk, armpll); > mtk_cpufreq_set_voltage(info, pre_vproc); > - return ret; > + goto out; > } > > /* Set parent of CPU clock back to the original PLL. */ > @@ -244,8 +250,7 @@ static int mtk_cpufreq_set_target(struct > cpufreq_policy *policy, > dev_err(cpu_dev, > "cpu%d: failed to re-parent cpu clock!\n", > policy->cpu); > mtk_cpufreq_set_voltage(info, inter_vproc); > - WARN_ON(1); > - return ret; > + goto out; > } > > /* > @@ -260,15 +265,72 @@ static int mtk_cpufreq_set_target(struct > cpufreq_policy *policy, > clk_set_parent(cpu_clk, info->inter_clk); > clk_set_rate(armpll, pre_freq_hz); > clk_set_parent(cpu_clk, armpll); > - return ret; > + goto out; > } > } > > - return 0; > + info->opp_freq = freq_hz; > + > +out: > + mutex_unlock(&info->reg_lock); > + > + return ret; > } > > #define DYNAMIC_POWER "dynamic-power-coefficient" > > +static int mtk_cpufreq_opp_notifier(struct notifier_block *nb, > + unsigned long event, void *data) > +{ > + struct dev_pm_opp *opp = data; > + struct dev_pm_opp *new_opp; > + struct mtk_cpu_dvfs_info *info; > + unsigned long freq, volt; > + struct cpufreq_policy *policy; > + int ret = 0; > + > + info = container_of(nb, struct mtk_cpu_dvfs_info, opp_nb); > + > + if (event == OPP_EVENT_ADJUST_VOLTAGE) { > + freq = dev_pm_opp_get_freq(opp); > + > + mutex_lock(&info->reg_lock); > + if (info->opp_freq == freq) { > + volt = dev_pm_opp_get_voltage(opp); > + ret = mtk_cpufreq_set_voltage(info, volt); > + if (ret) > + dev_err(info->cpu_dev, > + "failed to scale voltage: > %d\n", ret); > + } > + mutex_unlock(&info->reg_lock); > + } else if (event == OPP_EVENT_DISABLE) { > + freq = dev_pm_opp_get_freq(opp); > + > + /* case of current opp item is disabled */ > + if (info->opp_freq == freq) { > + freq = 1; > + new_opp = dev_pm_opp_find_freq_ceil(info- > >cpu_dev, > + &freq); > + if (IS_ERR(new_opp)) { > + dev_err(info->cpu_dev, > + "all opp items are > disabled\n"); > + ret = PTR_ERR(new_opp); > + return notifier_from_errno(ret); > + } > + > + dev_pm_opp_put(new_opp); > + policy = cpufreq_cpu_get(info->opp_cpu); > + if (policy) { > + cpufreq_driver_target(policy, freq / > 1000, > + CPUFREQ_RELATION_ > L); > + cpufreq_cpu_put(policy); > + } > + } > + } > + > + return notifier_from_errno(ret); > +} > + > static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, > int cpu) > { > struct device *cpu_dev; > @@ -357,6 +419,18 @@ static int mtk_cpu_dvfs_info_init(struct > mtk_cpu_dvfs_info *info, int cpu) > info->intermediate_voltage = dev_pm_opp_get_voltage(opp); > dev_pm_opp_put(opp); > > + mutex_init(&info->reg_lock); > + > + info->opp_cpu = cpu; > + info->opp_nb.notifier_call = mtk_cpufreq_opp_notifier; > + ret = dev_pm_opp_register_notifier(cpu_dev, &info->opp_nb); > + if (ret) { > + dev_err(cpu_dev, "cpu%d: failed to register opp > notifier\n", cpu); > + goto out_disable_inter_clock; > + } > + > + info->opp_freq = clk_get_rate(info->cpu_clk); > + > /* > * If SRAM regulator is present, software "voltage tracking" is > needed > * for this CPU power domain. > @@ -421,6 +495,7 @@ static void mtk_cpu_dvfs_info_release(struct > mtk_cpu_dvfs_info *info) > } > > dev_pm_opp_of_cpumask_remove_table(&info->cpus); > + dev_pm_opp_unregister_notifier(info->cpu_dev, &info->opp_nb); > } > > static int mtk_cpufreq_init(struct cpufreq_policy *policy)