From: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com> To: MyungJoo Ham <myungjoo.ham@samsung.com>, Kyungmin Park <kyungmin.park@samsung.com>, Chanwoo Choi <cw00.choi@samsung.com>, "Rob Herring" <robh+dt@kernel.org>, Mark Rutland <mark.rutland@arm.com>, "Matthias Brugger" <matthias.bgg@gmail.com>, "Rafael J . Wysocki" <rjw@rjwysocki.net>, Viresh Kumar <viresh.kumar@linaro.org>, Nishanth Menon <nm@ti.com>, "Stephen Boyd" <sboyd@kernel.org>, Liam Girdwood <lgirdwood@gmail.com>, Mark Brown <broonie@kernel.org> Cc: devicetree@vger.kernel.org, "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>, srv_heupstream@mediatek.com, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH 11/12] cpufreq: mediatek: add opp notification for SVS support Date: Wed, 20 May 2020 11:43:06 +0800 [thread overview] Message-ID: <20200520034307.20435-12-andrew-sh.cheng@mediatek.com> (raw) In-Reply-To: <20200520034307.20435-1-andrew-sh.cheng@mediatek.com> cpufreq should listen opp notification and do proper actions when receiving disable and voltage adjustment events, which are triggered when SVS is enabled. Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com> --- drivers/cpufreq/mediatek-cpufreq.c | 89 ++++++++++++++++++++++++++++++++++++-- 1 file changed, 85 insertions(+), 4 deletions(-) diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c index 4b479c110cc9..71395ab87ac7 100644 --- a/drivers/cpufreq/mediatek-cpufreq.c +++ b/drivers/cpufreq/mediatek-cpufreq.c @@ -42,6 +42,11 @@ struct mtk_cpu_dvfs_info { struct list_head list_head; int intermediate_voltage; bool need_voltage_tracking; + struct mutex lock; /* avoid notify and policy race condition */ + struct notifier_block opp_nb; + int opp_cpu; + unsigned long opp_freq; + int old_vproc; }; static LIST_HEAD(dvfs_info_list); @@ -192,11 +197,16 @@ static int mtk_cpufreq_voltage_tracking(struct mtk_cpu_dvfs_info *info, static int mtk_cpufreq_set_voltage(struct mtk_cpu_dvfs_info *info, int vproc) { + int ret; + if (info->need_voltage_tracking) - return mtk_cpufreq_voltage_tracking(info, vproc); + ret = mtk_cpufreq_voltage_tracking(info, vproc); else - return regulator_set_voltage(info->proc_reg, vproc, - vproc + VOLT_TOL); + ret = regulator_set_voltage(info->proc_reg, vproc, + MAX_VOLT_LIMIT); + if (!ret) + info->old_vproc = vproc; + return ret; } static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, @@ -214,7 +224,9 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, inter_vproc = info->intermediate_voltage; old_freq_hz = clk_get_rate(cpu_clk); - old_vproc = regulator_get_voltage(info->proc_reg); + old_vproc = info->old_vproc; + if (old_vproc == 0) + old_vproc = regulator_get_voltage(info->proc_reg); if (old_vproc < 0) { pr_err("%s: invalid Vproc value: %d\n", __func__, old_vproc); return old_vproc; @@ -231,6 +243,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, vproc = dev_pm_opp_get_voltage(opp); dev_pm_opp_put(opp); + mutex_lock(&info->lock); /* * If the new voltage or the intermediate voltage is higher than the * current voltage, scale up voltage first. @@ -242,6 +255,7 @@ 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; } } @@ -253,6 +267,7 @@ 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; } @@ -263,6 +278,7 @@ 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; } @@ -273,6 +289,7 @@ 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; } @@ -288,15 +305,69 @@ 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; } #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->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->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_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); + } + } else { + pr_err("%s: all opp items are disabled\n", + __func__); + } + } + } + + return notifier_from_errno(ret); +} + static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu) { struct device *cpu_dev; @@ -392,11 +463,21 @@ 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); + 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) { + pr_warn("cannot register opp notification\n"); + goto out_disable_inter_clock; + } + + mutex_init(&info->lock); 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); /* * If SRAM regulator is present, software "voltage tracking" is needed -- 2.12.5 _______________________________________________ Linux-mediatek mailing list Linux-mediatek@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-mediatek
WARNING: multiple messages have this Message-ID (diff)
From: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com> To: MyungJoo Ham <myungjoo.ham@samsung.com>, Kyungmin Park <kyungmin.park@samsung.com>, Chanwoo Choi <cw00.choi@samsung.com>, "Rob Herring" <robh+dt@kernel.org>, Mark Rutland <mark.rutland@arm.com>, "Matthias Brugger" <matthias.bgg@gmail.com>, "Rafael J . Wysocki" <rjw@rjwysocki.net>, Viresh Kumar <viresh.kumar@linaro.org>, Nishanth Menon <nm@ti.com>, "Stephen Boyd" <sboyd@kernel.org>, Liam Girdwood <lgirdwood@gmail.com>, Mark Brown <broonie@kernel.org> Cc: devicetree@vger.kernel.org, "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>, srv_heupstream@mediatek.com, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH 11/12] cpufreq: mediatek: add opp notification for SVS support Date: Wed, 20 May 2020 11:43:06 +0800 [thread overview] Message-ID: <20200520034307.20435-12-andrew-sh.cheng@mediatek.com> (raw) In-Reply-To: <20200520034307.20435-1-andrew-sh.cheng@mediatek.com> cpufreq should listen opp notification and do proper actions when receiving disable and voltage adjustment events, which are triggered when SVS is enabled. Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com> --- drivers/cpufreq/mediatek-cpufreq.c | 89 ++++++++++++++++++++++++++++++++++++-- 1 file changed, 85 insertions(+), 4 deletions(-) diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c index 4b479c110cc9..71395ab87ac7 100644 --- a/drivers/cpufreq/mediatek-cpufreq.c +++ b/drivers/cpufreq/mediatek-cpufreq.c @@ -42,6 +42,11 @@ struct mtk_cpu_dvfs_info { struct list_head list_head; int intermediate_voltage; bool need_voltage_tracking; + struct mutex lock; /* avoid notify and policy race condition */ + struct notifier_block opp_nb; + int opp_cpu; + unsigned long opp_freq; + int old_vproc; }; static LIST_HEAD(dvfs_info_list); @@ -192,11 +197,16 @@ static int mtk_cpufreq_voltage_tracking(struct mtk_cpu_dvfs_info *info, static int mtk_cpufreq_set_voltage(struct mtk_cpu_dvfs_info *info, int vproc) { + int ret; + if (info->need_voltage_tracking) - return mtk_cpufreq_voltage_tracking(info, vproc); + ret = mtk_cpufreq_voltage_tracking(info, vproc); else - return regulator_set_voltage(info->proc_reg, vproc, - vproc + VOLT_TOL); + ret = regulator_set_voltage(info->proc_reg, vproc, + MAX_VOLT_LIMIT); + if (!ret) + info->old_vproc = vproc; + return ret; } static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, @@ -214,7 +224,9 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, inter_vproc = info->intermediate_voltage; old_freq_hz = clk_get_rate(cpu_clk); - old_vproc = regulator_get_voltage(info->proc_reg); + old_vproc = info->old_vproc; + if (old_vproc == 0) + old_vproc = regulator_get_voltage(info->proc_reg); if (old_vproc < 0) { pr_err("%s: invalid Vproc value: %d\n", __func__, old_vproc); return old_vproc; @@ -231,6 +243,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, vproc = dev_pm_opp_get_voltage(opp); dev_pm_opp_put(opp); + mutex_lock(&info->lock); /* * If the new voltage or the intermediate voltage is higher than the * current voltage, scale up voltage first. @@ -242,6 +255,7 @@ 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; } } @@ -253,6 +267,7 @@ 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; } @@ -263,6 +278,7 @@ 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; } @@ -273,6 +289,7 @@ 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; } @@ -288,15 +305,69 @@ 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; } #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->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->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_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); + } + } else { + pr_err("%s: all opp items are disabled\n", + __func__); + } + } + } + + return notifier_from_errno(ret); +} + static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu) { struct device *cpu_dev; @@ -392,11 +463,21 @@ 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); + 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) { + pr_warn("cannot register opp notification\n"); + goto out_disable_inter_clock; + } + + mutex_init(&info->lock); 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); /* * If SRAM regulator is present, software "voltage tracking" is needed -- 2.12.5 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2020-05-20 3:52 UTC|newest] Thread overview: 87+ messages / expand[flat|nested] mbox.gz Atom feed top [not found] <CGME20200520034324epcas1p3affbd24bd1f3fe40d51baade07c1abba@epcas1p3.samsung.com> 2020-05-20 3:42 ` [PATCH 00/12] Add cpufreq and cci devfreq for mt8183, and SVS support Andrew-sh.Cheng 2020-05-20 3:42 ` Andrew-sh.Cheng 2020-05-20 3:42 ` [PATCH 01/12] OPP: Allow required-opps even if the device doesn't have power-domains Andrew-sh.Cheng 2020-05-20 3:42 ` Andrew-sh.Cheng 2020-05-20 14:54 ` Matthias Brugger 2020-05-20 14:54 ` Matthias Brugger 2020-05-20 14:54 ` Matthias Brugger 2020-05-21 1:50 ` andrew-sh.cheng 2020-05-21 1:50 ` andrew-sh.cheng 2020-05-20 3:42 ` [PATCH 02/12] OPP: Add function to look up required OPP's for a given OPP Andrew-sh.Cheng 2020-05-20 3:42 ` Andrew-sh.Cheng 2020-05-20 3:42 ` [PATCH 03/12] OPP: Improve required-opps linking Andrew-sh.Cheng 2020-05-20 3:42 ` Andrew-sh.Cheng 2020-05-20 22:46 ` kbuild test robot 2020-05-21 1:10 ` kbuild test robot 2020-05-20 3:42 ` [PATCH 04/12] PM / devfreq: Cache OPP table reference in devfreq Andrew-sh.Cheng 2020-05-20 3:42 ` Andrew-sh.Cheng 2020-05-20 3:43 ` [PATCH 05/12] PM / devfreq: Add required OPPs support to passive governor Andrew-sh.Cheng 2020-05-20 3:43 ` Andrew-sh.Cheng 2020-05-20 3:43 ` [PATCH 06/12] PM / devfreq: Add cpu based scaling support to passive_governor Andrew-sh.Cheng 2020-05-20 3:43 ` Andrew-sh.Cheng 2020-05-28 5:03 ` Chanwoo Choi 2020-05-28 5:03 ` Chanwoo Choi 2020-05-28 5:03 ` Chanwoo Choi 2020-05-28 6:14 ` Chanwoo Choi 2020-05-28 6:14 ` Chanwoo Choi 2020-05-28 6:14 ` Chanwoo Choi 2020-05-28 7:17 ` Chanwoo Choi 2020-05-28 7:17 ` Chanwoo Choi 2020-05-28 7:17 ` Chanwoo Choi 2020-06-02 12:23 ` andrew-sh.cheng 2020-06-02 12:23 ` andrew-sh.cheng 2020-06-03 4:12 ` Chanwoo Choi 2020-06-03 4:12 ` Chanwoo Choi 2020-06-03 4:12 ` Chanwoo Choi 2020-06-02 11:43 ` andrew-sh.cheng 2020-06-02 11:43 ` andrew-sh.cheng 2020-06-03 4:07 ` Chanwoo Choi 2020-06-03 4:07 ` Chanwoo Choi 2020-06-03 4:07 ` Chanwoo Choi 2020-06-17 7:59 ` andrew-sh.cheng 2020-06-17 7:59 ` andrew-sh.cheng 2020-05-20 3:43 ` [PATCH 07/12] cpufreq: mediatek: Enable clock and regulator Andrew-sh.Cheng 2020-05-20 3:43 ` Andrew-sh.Cheng 2020-05-20 3:43 ` [PATCH 08/12] dt-bindings: devfreq: add compatible for mt8183 cci devfreq Andrew-sh.Cheng 2020-05-20 3:43 ` Andrew-sh.Cheng 2020-05-28 7:42 ` Chanwoo Choi 2020-05-28 7:42 ` Chanwoo Choi 2020-05-28 7:42 ` Chanwoo Choi 2020-06-17 12:05 ` andrew-sh.cheng 2020-06-17 12:05 ` andrew-sh.cheng 2020-05-20 3:43 ` [PATCH 09/12] devfreq: add mediatek " Andrew-sh.Cheng 2020-05-20 3:43 ` Andrew-sh.Cheng 2020-05-20 12:31 ` Mark Brown 2020-05-20 12:31 ` Mark Brown 2020-05-20 12:31 ` Mark Brown 2020-05-21 8:52 ` andrew-sh.cheng 2020-05-21 8:52 ` andrew-sh.cheng 2020-05-21 8:52 ` andrew-sh.cheng 2020-05-28 7:35 ` Chanwoo Choi 2020-05-28 7:35 ` Chanwoo Choi 2020-05-28 7:35 ` Chanwoo Choi 2020-05-28 8:00 ` Chanwoo Choi 2020-05-28 8:00 ` Chanwoo Choi 2020-05-28 8:00 ` Chanwoo Choi 2020-05-20 3:43 ` [PATCH 10/12] opp: Modify opp API, dev_pm_opp_get_freq(), find freq in opp, even it is disabled Andrew-sh.Cheng 2020-05-20 3:43 ` Andrew-sh.Cheng 2020-05-20 3:43 ` Andrew-sh.Cheng [this message] 2020-05-20 3:43 ` [PATCH 11/12] cpufreq: mediatek: add opp notification for SVS support Andrew-sh.Cheng 2020-05-20 3:43 ` [PATCH 12/12] devfreq: mediatek: cci devfreq register " Andrew-sh.Cheng 2020-05-20 3:43 ` Andrew-sh.Cheng 2020-05-20 4:10 ` [PATCH 00/12] Add cpufreq and cci devfreq for mt8183, and " Chanwoo Choi 2020-05-20 4:10 ` Chanwoo Choi 2020-05-20 4:10 ` Chanwoo Choi 2020-05-20 5:36 ` andrew-sh.cheng 2020-05-20 5:36 ` andrew-sh.cheng 2020-05-20 6:24 ` Chanwoo Choi 2020-05-20 6:24 ` Chanwoo Choi 2020-05-20 6:24 ` Chanwoo Choi 2020-05-20 7:10 ` andrew-sh.cheng 2020-05-20 7:10 ` andrew-sh.cheng 2020-05-20 14:53 ` Matthias Brugger 2020-05-20 14:53 ` Matthias Brugger 2020-05-20 14:53 ` Matthias Brugger 2020-06-15 7:31 ` Viresh Kumar 2020-06-15 7:31 ` Viresh Kumar 2020-06-15 7:31 ` Viresh Kumar
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