Add a notifier to receive OPP voltage adjustment event which is triggered by voltage change of OPP entries done by Mediatek SVS (Smart Voltage Scaling) engine. CC: Stephen Boyd <sboyd@xxxxxxxxxxxxxx> Signed-off-by: Pi-Cheng Chen <pi-cheng.chen@xxxxxxxxxx> --- This patch is modify from the patch which adds[1] a notifier in cpufreq-dt to handle OPP voltage adjust event. This patch relies on the on the runtime voltage adjustment mechanism of OPP introduced in the same patchset. [1] https://lkml.org/lkml/2015/9/18/833 --- drivers/cpufreq/mt8173-cpufreq.c | 55 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) diff --git a/drivers/cpufreq/mt8173-cpufreq.c b/drivers/cpufreq/mt8173-cpufreq.c index 1ede917..248f6e8 100644 --- a/drivers/cpufreq/mt8173-cpufreq.c +++ b/drivers/cpufreq/mt8173-cpufreq.c @@ -48,8 +48,11 @@ struct mtk_cpu_dvfs_info { struct clk *cpu_clk; struct clk *inter_clk; struct thermal_cooling_device *cdev; + struct mutex lock; + struct notifier_block opp_nb; struct list_head list_head; int intermediate_voltage; + unsigned long opp_freq; bool need_voltage_tracking; }; @@ -211,6 +214,33 @@ static int mtk_cpufreq_set_voltage(struct mtk_cpu_dvfs_info *info, int vproc) vproc + VOLT_TOL); } +static int mtk_cpufreq_opp_notifier(struct notifier_block *nb, + unsigned long event, void *data) +{ + struct dev_pm_opp *opp = data; + struct mtk_cpu_dvfs_info *info = container_of(nb, + struct mtk_cpu_dvfs_info, + opp_nb); + unsigned long freq, volt; + int ret = 0; + + if (event == OPP_EVENT_ADJUST_VOLTAGE) { + freq = dev_pm_opp_get_freq(opp); + + if (info->opp_freq == freq) { + volt = dev_pm_opp_get_voltage(opp); + mutex_lock(&info->lock); + ret = mtk_cpufreq_set_voltage(info, volt); + mutex_unlock(&info->lock); + if (ret) + dev_err(info->cpu_dev, + "failed to scale voltage: %d\n", ret); + } + } + + return notifier_from_errno(ret); +} + static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, unsigned int index) { @@ -245,6 +275,8 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, vproc = dev_pm_opp_get_voltage(opp); rcu_read_unlock(); + mutex_lock(&info->lock); + /* * If the new voltage or the intermediate voltage is higher than the * current voltage, scale up voltage first. @@ -256,6 +288,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, pr_err("cpu%d: failed to scale up voltage!\n", policy->cpu); mtk_cpufreq_set_voltage(info, old_vproc); + mutex_unlock(&info->lock); return ret; } } @@ -267,6 +300,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, policy->cpu); mtk_cpufreq_set_voltage(info, old_vproc); WARN_ON(1); + mutex_unlock(&info->lock); return ret; } @@ -277,6 +311,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, policy->cpu); clk_set_parent(cpu_clk, armpll); mtk_cpufreq_set_voltage(info, old_vproc); + mutex_unlock(&info->lock); return ret; } @@ -287,6 +322,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, policy->cpu); mtk_cpufreq_set_voltage(info, inter_vproc); WARN_ON(1); + mutex_unlock(&info->lock); return ret; } @@ -302,10 +338,14 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, clk_set_parent(cpu_clk, info->inter_clk); clk_set_rate(armpll, old_freq_hz); clk_set_parent(cpu_clk, armpll); + mutex_unlock(&info->lock); return ret; } } + info->opp_freq = freq_hz; + mutex_unlock(&info->lock); + return 0; } @@ -343,6 +383,7 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu) struct dev_pm_opp *opp; unsigned long rate; int ret; + struct srcu_notifier_head *opp_srcu_head; cpu_dev = get_cpu_device(cpu); if (!cpu_dev) { @@ -417,11 +458,25 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu) info->intermediate_voltage = dev_pm_opp_get_voltage(opp); rcu_read_unlock(); + opp_srcu_head = dev_pm_opp_get_notifier(cpu_dev); + if (IS_ERR(opp_srcu_head)) { + ret = PTR_ERR(opp_srcu_head); + goto out_free_opp_table; + } + + info->opp_nb.notifier_call = mtk_cpufreq_opp_notifier; + ret = srcu_notifier_chain_register(opp_srcu_head, &info->opp_nb); + if (ret) + goto out_free_opp_table; + info->cpu_dev = cpu_dev; info->proc_reg = proc_reg; info->sram_reg = IS_ERR(sram_reg) ? NULL : sram_reg; info->cpu_clk = cpu_clk; info->inter_clk = inter_clk; + info->opp_freq = clk_get_rate(cpu_clk); + + mutex_init(&info->lock); /* * If SRAM regulator is present, software "voltage tracking" is needed -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
