target/linux/mediatek/patches-5.15/350-11-cpufreq-mediatek-Add-opp-notification-support.patch

   1 From 01be227eff7e5fc01f7c8de8f6daddd5fb17ddd1 Mon Sep 17 00:00:00 2001
   2 From: Rex-BC Chen <rex-bc.chen@mediatek.com>
   3 Date: Thu, 5 May 2022 19:52:21 +0800
   4 Subject: [PATCH 11/21] cpufreq: mediatek: Add opp notification support
   5
   6 From this opp notifier, cpufreq should listen to opp notification and do
   7 proper actions when receiving events of disable and voltage adjustment.
   8
   9 One of the user for this opp notifier is MediaTek SVS.
  10 The MediaTek Smart Voltage Scaling (SVS) is a hardware which calculates
  11 suitable SVS bank voltages to OPP voltage table.
  12
  13 Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
  14 Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
  15 Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
  16 Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
  17 [ Viresh: Renamed opp_freq as current_freq and moved its initialization ]
  18 Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
  19 ---
  20  drivers/cpufreq/mediatek-cpufreq.c | 90 +++++++++++++++++++++++++++---
  21  1 file changed, 82 insertions(+), 8 deletions(-)
  22
  23 --- a/drivers/cpufreq/mediatek-cpufreq.c
  24 +++ b/drivers/cpufreq/mediatek-cpufreq.c
  25 @@ -46,6 +46,11 @@ struct mtk_cpu_dvfs_info {
  26         int intermediate_voltage;
  27         bool need_voltage_tracking;
  28         int pre_vproc;
  29 +       /* Avoid race condition for regulators between notify and policy */
  30 +       struct mutex reg_lock;
  31 +       struct notifier_block opp_nb;
  32 +       unsigned int opp_cpu;
  33 +       unsigned long current_freq;
  34         const struct mtk_cpufreq_platform_data *soc_data;
  35         int vtrack_max;
  36  };
  37 @@ -182,6 +187,8 @@ static int mtk_cpufreq_set_target(struct
  38
  39         pre_freq_hz = clk_get_rate(cpu_clk);
  40
  41 +       mutex_lock(&info->reg_lock);
  42 +
  43         if (unlikely(info->pre_vproc <= 0))
  44                 pre_vproc = regulator_get_voltage(info->proc_reg);
  45         else
  46 @@ -214,7 +221,7 @@ static int mtk_cpufreq_set_target(struct
  47                         dev_err(cpu_dev,
  48                                 "cpu%d: failed to scale up voltage!\n", policy->cpu);
  49                         mtk_cpufreq_set_voltage(info, pre_vproc);
  50 -                       return ret;
  51 +                       goto out;
  52                 }
  53         }
  54
  55 @@ -224,8 +231,7 @@ static int mtk_cpufreq_set_target(struct
  56                 dev_err(cpu_dev,
  57                         "cpu%d: failed to re-parent cpu clock!\n", policy->cpu);
  58                 mtk_cpufreq_set_voltage(info, pre_vproc);
  59 -               WARN_ON(1);
  60 -               return ret;
  61 +               goto out;
  62         }
  63
  64         /* Set the original PLL to target rate. */
  65 @@ -235,7 +241,7 @@ static int mtk_cpufreq_set_target(struct
  66                         "cpu%d: failed to scale cpu clock rate!\n", policy->cpu);
  67                 clk_set_parent(cpu_clk, armpll);
  68                 mtk_cpufreq_set_voltage(info, pre_vproc);
  69 -               return ret;
  70 +               goto out;
  71         }
  72
  73         /* Set parent of CPU clock back to the original PLL. */
  74 @@ -244,8 +250,7 @@ static int mtk_cpufreq_set_target(struct
  75                 dev_err(cpu_dev,
  76                         "cpu%d: failed to re-parent cpu clock!\n", policy->cpu);
  77                 mtk_cpufreq_set_voltage(info, inter_vproc);
  78 -               WARN_ON(1);
  79 -               return ret;
  80 +               goto out;
  81         }
  82
  83         /*
  84 @@ -260,15 +265,72 @@ static int mtk_cpufreq_set_target(struct
  85                         clk_set_parent(cpu_clk, info->inter_clk);
  86                         clk_set_rate(armpll, pre_freq_hz);
  87                         clk_set_parent(cpu_clk, armpll);
  88 -                       return ret;
  89 +                       goto out;
  90                 }
  91         }
  92
  93 -       return 0;
  94 +       info->current_freq = freq_hz;
  95 +
  96 +out:
  97 +       mutex_unlock(&info->reg_lock);
  98 +
  99 +       return ret;
 100  }
 101
 102  #define DYNAMIC_POWER "dynamic-power-coefficient"
 103
 104 +static int mtk_cpufreq_opp_notifier(struct notifier_block *nb,
 105 +                                   unsigned long event, void *data)
 106 +{
 107 +       struct dev_pm_opp *opp = data;
 108 +       struct dev_pm_opp *new_opp;
 109 +       struct mtk_cpu_dvfs_info *info;
 110 +       unsigned long freq, volt;
 111 +       struct cpufreq_policy *policy;
 112 +       int ret = 0;
 113 +
 114 +       info = container_of(nb, struct mtk_cpu_dvfs_info, opp_nb);
 115 +
 116 +       if (event == OPP_EVENT_ADJUST_VOLTAGE) {
 117 +               freq = dev_pm_opp_get_freq(opp);
 118 +
 119 +               mutex_lock(&info->reg_lock);
 120 +               if (info->current_freq == freq) {
 121 +                       volt = dev_pm_opp_get_voltage(opp);
 122 +                       ret = mtk_cpufreq_set_voltage(info, volt);
 123 +                       if (ret)
 124 +                               dev_err(info->cpu_dev,
 125 +                                       "failed to scale voltage: %d\n", ret);
 126 +               }
 127 +               mutex_unlock(&info->reg_lock);
 128 +       } else if (event == OPP_EVENT_DISABLE) {
 129 +               freq = dev_pm_opp_get_freq(opp);
 130 +
 131 +               /* case of current opp item is disabled */
 132 +               if (info->current_freq == freq) {
 133 +                       freq = 1;
 134 +                       new_opp = dev_pm_opp_find_freq_ceil(info->cpu_dev,
 135 +                                                           &freq);
 136 +                       if (IS_ERR(new_opp)) {
 137 +                               dev_err(info->cpu_dev,
 138 +                                       "all opp items are disabled\n");
 139 +                               ret = PTR_ERR(new_opp);
 140 +                               return notifier_from_errno(ret);
 141 +                       }
 142 +
 143 +                       dev_pm_opp_put(new_opp);
 144 +                       policy = cpufreq_cpu_get(info->opp_cpu);
 145 +                       if (policy) {
 146 +                               cpufreq_driver_target(policy, freq / 1000,
 147 +                                                     CPUFREQ_RELATION_L);
 148 +                               cpufreq_cpu_put(policy);
 149 +                       }
 150 +               }
 151 +       }
 152 +
 153 +       return notifier_from_errno(ret);
 154 +}
 155 +
 156  static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
 157  {
 158         struct device *cpu_dev;
 159 @@ -357,6 +419,17 @@ static int mtk_cpu_dvfs_info_init(struct
 160         info->intermediate_voltage = dev_pm_opp_get_voltage(opp);
 161         dev_pm_opp_put(opp);
 162
 163 +       mutex_init(&info->reg_lock);
 164 +       info->current_freq = clk_get_rate(info->cpu_clk);
 165 +
 166 +       info->opp_cpu = cpu;
 167 +       info->opp_nb.notifier_call = mtk_cpufreq_opp_notifier;
 168 +       ret = dev_pm_opp_register_notifier(cpu_dev, &info->opp_nb);
 169 +       if (ret) {
 170 +               dev_err(cpu_dev, "cpu%d: failed to register opp notifier\n", cpu);
 171 +               goto out_disable_inter_clock;
 172 +       }
 173 +
 174         /*
 175          * If SRAM regulator is present, software "voltage tracking" is needed
 176          * for this CPU power domain.
 177 @@ -421,6 +494,7 @@ static void mtk_cpu_dvfs_info_release(st
 178         }
 179
 180         dev_pm_opp_of_cpumask_remove_table(&info->cpus);
 181 +       dev_pm_opp_unregister_notifier(info->cpu_dev, &info->opp_nb);
 182  }
 183
 184  static int mtk_cpufreq_init(struct cpufreq_policy *policy)