target/linux/bcm27xx/patches-5.4/950-0779-clk-bcm-rpi-Use-CCF-boundaries-instead-of-rolling-ou.patch

   1 From cd72d75cfb216a7ef15ec8649e57b03b4fc48b62 Mon Sep 17 00:00:00 2001
   2 From: Maxime Ripard <maxime@cerno.tech>
   3 Date: Wed, 27 May 2020 11:13:52 +0200
   4 Subject: [PATCH] clk: bcm: rpi: Use CCF boundaries instead of
   5  rolling our own
   6
   7 The raspberrypi firmware clock driver has a min_rate / max_rate clamping by
   8 storing the info it needs in a private structure.
   9
  10 However, the CCF already provides such a facility, so we can switch to it
  11 to remove the boilerplate.
  12
  13 Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
  14 Signed-off-by: Maxime Ripard <maxime@cerno.tech>
  15 ---
  16  drivers/clk/bcm/clk-raspberrypi.c | 49 ++++++++++++++++++++-----------
  17  1 file changed, 32 insertions(+), 17 deletions(-)
  18
  19 --- a/drivers/clk/bcm/clk-raspberrypi.c
  20 +++ b/drivers/clk/bcm/clk-raspberrypi.c
  21 @@ -57,9 +57,6 @@ struct raspberrypi_clk_data {
  22         struct clk_hw hw;
  23         unsigned id;
  24
  25 -       unsigned long min_rate;
  26 -       unsigned long max_rate;
  27 -
  28         struct raspberrypi_clk *rpi;
  29  };
  30
  31 @@ -177,13 +174,11 @@ static int raspberrypi_fw_pll_set_rate(s
  32  static int raspberrypi_pll_determine_rate(struct clk_hw *hw,
  33                                           struct clk_rate_request *req)
  34  {
  35 -       struct raspberrypi_clk_data *data =
  36 -               container_of(hw, struct raspberrypi_clk_data, hw);
  37         u64 div, final_rate;
  38         u32 ndiv, fdiv;
  39
  40         /* We can't use req->rate directly as it would overflow */
  41 -       final_rate = clamp(req->rate, data->min_rate, data->max_rate);
  42 +       final_rate = clamp(req->rate, req->min_rate, req->max_rate);
  43
  44         div = (u64)final_rate << A2W_PLL_FRAC_BITS;
  45         do_div(div, req->best_parent_rate);
  46 @@ -254,16 +249,15 @@ static struct clk_hw *raspberrypi_regist
  47         dev_info(rpi->dev, "CPU frequency range: min %u, max %u\n",
  48                  min_rate, max_rate);
  49
  50 -       data->min_rate = min_rate * RPI_FIRMWARE_PLLB_ARM_DIV_RATE;
  51 -       data->max_rate = max_rate * RPI_FIRMWARE_PLLB_ARM_DIV_RATE;
  52 -
  53         data->hw.init = &init;
  54
  55         ret = devm_clk_hw_register(rpi->dev, &data->hw);
  56 -       if (ret)
  57 -               return ERR_PTR(ret);
  58 +       if (!ret)
  59 +               clk_hw_set_rate_range(&data->hw,
  60 +                                     min_rate * RPI_FIRMWARE_PLLB_ARM_DIV_RATE,
  61 +                                     max_rate * RPI_FIRMWARE_PLLB_ARM_DIV_RATE);
  62
  63 -       return &data->hw;
  64 +       return ret;
  65  }
  66
  67  static struct clk_fixed_factor raspberrypi_clk_pllb_arm = {
  68 @@ -299,22 +293,22 @@ static struct clk_hw *raspberrypi_regist
  69         return &raspberrypi_clk_pllb_arm.hw;
  70  }
  71
  72 -static long raspberrypi_fw_dumb_round_rate(struct clk_hw *hw,
  73 -                                          unsigned long rate,
  74 -                                          unsigned long *parent_rate)
  75 +static int raspberrypi_fw_dumb_determine_rate(struct clk_hw *hw,
  76 +                                             struct clk_rate_request *req)
  77  {
  78         /*
  79          * The firmware will do the rounding but that isn't part of
  80          * the interface with the firmware, so we just do our best
  81          * here.
  82          */
  83 -       return rate;
  84 +       req->rate = clamp(req->rate, req->min_rate, req->max_rate);
  85 +       return 0;
  86  }
  87
  88  static const struct clk_ops raspberrypi_firmware_clk_ops = {
  89         .is_prepared    = raspberrypi_fw_is_prepared,
  90         .recalc_rate    = raspberrypi_fw_get_rate,
  91 -       .round_rate     = raspberrypi_fw_dumb_round_rate,
  92 +       .determine_rate = raspberrypi_fw_dumb_determine_rate,
  93         .set_rate       = raspberrypi_fw_set_rate,
  94  };
  95
  96 @@ -324,6 +318,7 @@ static struct clk_hw *raspberrypi_clk_re
  97  {
  98         struct raspberrypi_clk_data *data;
  99         struct clk_init_data init = {};
 100 +       u32 min_rate, max_rate;
 101         int ret;
 102
 103         if (id == RPI_FIRMWARE_ARM_CLK_ID) {
 104 @@ -351,10 +346,30 @@ static struct clk_hw *raspberrypi_clk_re
 105
 106         data->hw.init = &init;
 107
 108 +       ret = raspberrypi_clock_property(rpi->firmware, data,
 109 +                                        RPI_FIRMWARE_GET_MIN_CLOCK_RATE,
 110 +                                        &min_rate);
 111 +       if (ret) {
 112 +               dev_err(rpi->dev, "Failed to get %s min freq: %d\n",
 113 +                       init.name, ret);
 114 +               return ERR_PTR(ret);
 115 +       }
 116 +
 117 +       ret = raspberrypi_clock_property(rpi->firmware, data,
 118 +                                        RPI_FIRMWARE_GET_MAX_CLOCK_RATE,
 119 +                                        &max_rate);
 120 +       if (ret) {
 121 +               dev_err(rpi->dev, "Failed to get %s max freq: %d\n",
 122 +                       init.name, ret);
 123 +               return ERR_PTR(ret);
 124 +       }
 125 +
 126         ret = devm_clk_hw_register(rpi->dev, &data->hw);
 127         if (ret)
 128                 return ERR_PTR(ret);
 129
 130 +       clk_hw_set_rate_range(&data->hw, min_rate, max_rate);
 131 +
 132         return &data->hw;
 133  }
 134