target/linux/brcm2708/patches-4.9/950-0155-clk-bcm2835-Don-t-rate-change-PLLs-on-behalf-of-DSI-.patch

   1 From 999db52750c062708532e1357ea3942cc619794f Mon Sep 17 00:00:00 2001
   2 From: Eric Anholt <eric@anholt.net>
   3 Date: Wed, 18 Jan 2017 07:31:55 +1100
   4 Subject: [PATCH] clk: bcm2835: Don't rate change PLLs on behalf of DSI PLL
   5  dividers.
   6
   7 Our core PLLs are intended to be configured once and left alone.  With
   8 the SET_RATE_PARENT, asking to set the PLLD_DSI1 clock rate would
   9 change PLLD just to get closer to the requested DSI clock, thus
  10 changing PLLD_PER, the UART and ethernet PHY clock rates downstream of
  11 it, and breaking ethernet.
  12
  13 We *do* want PLLH to change so that PLLH_AUX can be exactly the value
  14 we want, though.  Thus, we need to have a per-divider policy of
  15 whether to pass rate changes up.
  16
  17 Signed-off-by: Eric Anholt <eric@anholt.net>
  18 Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
  19 (cherry picked from commit 55486091bd1e1c5ed28c43c0d6b3392468a9adb5)
  20 ---
  21  drivers/clk/bcm/clk-bcm2835.c | 42 ++++++++++++++++++++++++++++--------------
  22  1 file changed, 28 insertions(+), 14 deletions(-)
  23
  24 --- a/drivers/clk/bcm/clk-bcm2835.c
  25 +++ b/drivers/clk/bcm/clk-bcm2835.c
  26 @@ -428,6 +428,7 @@ struct bcm2835_pll_divider_data {
  27         u32 load_mask;
  28         u32 hold_mask;
  29         u32 fixed_divider;
  30 +       u32 flags;
  31  };
  32
  33  struct bcm2835_clock_data {
  34 @@ -1252,7 +1253,7 @@ bcm2835_register_pll_divider(struct bcm2
  35         init.num_parents = 1;
  36         init.name = divider_name;
  37         init.ops = &bcm2835_pll_divider_clk_ops;
  38 -       init.flags = CLK_SET_RATE_PARENT | CLK_IGNORE_UNUSED;
  39 +       init.flags = data->flags | CLK_IGNORE_UNUSED;
  40
  41         divider = devm_kzalloc(cprman->dev, sizeof(*divider), GFP_KERNEL);
  42         if (!divider)
  43 @@ -1475,7 +1476,8 @@ static const struct bcm2835_clk_desc clk
  44                 .a2w_reg = A2W_PLLA_CORE,
  45                 .load_mask = CM_PLLA_LOADCORE,
  46                 .hold_mask = CM_PLLA_HOLDCORE,
  47 -               .fixed_divider = 1),
  48 +               .fixed_divider = 1,
  49 +               .flags = CLK_SET_RATE_PARENT),
  50         [BCM2835_PLLA_PER]      = REGISTER_PLL_DIV(
  51                 .name = "plla_per",
  52                 .source_pll = "plla",
  53 @@ -1483,7 +1485,8 @@ static const struct bcm2835_clk_desc clk
  54                 .a2w_reg = A2W_PLLA_PER,
  55                 .load_mask = CM_PLLA_LOADPER,
  56                 .hold_mask = CM_PLLA_HOLDPER,
  57 -               .fixed_divider = 1),
  58 +               .fixed_divider = 1,
  59 +               .flags = CLK_SET_RATE_PARENT),
  60         [BCM2835_PLLA_DSI0]     = REGISTER_PLL_DIV(
  61                 .name = "plla_dsi0",
  62                 .source_pll = "plla",
  63 @@ -1499,7 +1502,8 @@ static const struct bcm2835_clk_desc clk
  64                 .a2w_reg = A2W_PLLA_CCP2,
  65                 .load_mask = CM_PLLA_LOADCCP2,
  66                 .hold_mask = CM_PLLA_HOLDCCP2,
  67 -               .fixed_divider = 1),
  68 +               .fixed_divider = 1,
  69 +               .flags = CLK_SET_RATE_PARENT),
  70
  71         /* PLLB is used for the ARM's clock. */
  72         [BCM2835_PLLB]          = REGISTER_PLL(
  73 @@ -1523,7 +1527,8 @@ static const struct bcm2835_clk_desc clk
  74                 .a2w_reg = A2W_PLLB_ARM,
  75                 .load_mask = CM_PLLB_LOADARM,
  76                 .hold_mask = CM_PLLB_HOLDARM,
  77 -               .fixed_divider = 1),
  78 +               .fixed_divider = 1,
  79 +               .flags = CLK_SET_RATE_PARENT),
  80
  81         /*
  82          * PLLC is the core PLL, used to drive the core VPU clock.
  83 @@ -1552,7 +1557,8 @@ static const struct bcm2835_clk_desc clk
  84                 .a2w_reg = A2W_PLLC_CORE0,
  85                 .load_mask = CM_PLLC_LOADCORE0,
  86                 .hold_mask = CM_PLLC_HOLDCORE0,
  87 -               .fixed_divider = 1),
  88 +               .fixed_divider = 1,
  89 +               .flags = CLK_SET_RATE_PARENT),
  90         [BCM2835_PLLC_CORE1]    = REGISTER_PLL_DIV(
  91                 .name = "pllc_core1",
  92                 .source_pll = "pllc",
  93 @@ -1560,7 +1566,8 @@ static const struct bcm2835_clk_desc clk
  94                 .a2w_reg = A2W_PLLC_CORE1,
  95                 .load_mask = CM_PLLC_LOADCORE1,
  96                 .hold_mask = CM_PLLC_HOLDCORE1,
  97 -               .fixed_divider = 1),
  98 +               .fixed_divider = 1,
  99 +               .flags = CLK_SET_RATE_PARENT),
 100         [BCM2835_PLLC_CORE2]    = REGISTER_PLL_DIV(
 101                 .name = "pllc_core2",
 102                 .source_pll = "pllc",
 103 @@ -1568,7 +1575,8 @@ static const struct bcm2835_clk_desc clk
 104                 .a2w_reg = A2W_PLLC_CORE2,
 105                 .load_mask = CM_PLLC_LOADCORE2,
 106                 .hold_mask = CM_PLLC_HOLDCORE2,
 107 -               .fixed_divider = 1),
 108 +               .fixed_divider = 1,
 109 +               .flags = CLK_SET_RATE_PARENT),
 110         [BCM2835_PLLC_PER]      = REGISTER_PLL_DIV(
 111                 .name = "pllc_per",
 112                 .source_pll = "pllc",
 113 @@ -1576,7 +1584,8 @@ static const struct bcm2835_clk_desc clk
 114                 .a2w_reg = A2W_PLLC_PER,
 115                 .load_mask = CM_PLLC_LOADPER,
 116                 .hold_mask = CM_PLLC_HOLDPER,
 117 -               .fixed_divider = 1),
 118 +               .fixed_divider = 1,
 119 +               .flags = CLK_SET_RATE_PARENT),
 120
 121         /*
 122          * PLLD is the display PLL, used to drive DSI display panels.
 123 @@ -1605,7 +1614,8 @@ static const struct bcm2835_clk_desc clk
 124                 .a2w_reg = A2W_PLLD_CORE,
 125                 .load_mask = CM_PLLD_LOADCORE,
 126                 .hold_mask = CM_PLLD_HOLDCORE,
 127 -               .fixed_divider = 1),
 128 +               .fixed_divider = 1,
 129 +               .flags = CLK_SET_RATE_PARENT),
 130         [BCM2835_PLLD_PER]      = REGISTER_PLL_DIV(
 131                 .name = "plld_per",
 132                 .source_pll = "plld",
 133 @@ -1613,7 +1623,8 @@ static const struct bcm2835_clk_desc clk
 134                 .a2w_reg = A2W_PLLD_PER,
 135                 .load_mask = CM_PLLD_LOADPER,
 136                 .hold_mask = CM_PLLD_HOLDPER,
 137 -               .fixed_divider = 1),
 138 +               .fixed_divider = 1,
 139 +               .flags = CLK_SET_RATE_PARENT),
 140         [BCM2835_PLLD_DSI0]     = REGISTER_PLL_DIV(
 141                 .name = "plld_dsi0",
 142                 .source_pll = "plld",
 143 @@ -1658,7 +1669,8 @@ static const struct bcm2835_clk_desc clk
 144                 .a2w_reg = A2W_PLLH_RCAL,
 145                 .load_mask = CM_PLLH_LOADRCAL,
 146                 .hold_mask = 0,
 147 -               .fixed_divider = 10),
 148 +               .fixed_divider = 10,
 149 +               .flags = CLK_SET_RATE_PARENT),
 150         [BCM2835_PLLH_AUX]      = REGISTER_PLL_DIV(
 151                 .name = "pllh_aux",
 152                 .source_pll = "pllh",
 153 @@ -1666,7 +1678,8 @@ static const struct bcm2835_clk_desc clk
 154                 .a2w_reg = A2W_PLLH_AUX,
 155                 .load_mask = CM_PLLH_LOADAUX,
 156                 .hold_mask = 0,
 157 -               .fixed_divider = 1),
 158 +               .fixed_divider = 1,
 159 +               .flags = CLK_SET_RATE_PARENT),
 160         [BCM2835_PLLH_PIX]      = REGISTER_PLL_DIV(
 161                 .name = "pllh_pix",
 162                 .source_pll = "pllh",
 163 @@ -1674,7 +1687,8 @@ static const struct bcm2835_clk_desc clk
 164                 .a2w_reg = A2W_PLLH_PIX,
 165                 .load_mask = CM_PLLH_LOADPIX,
 166                 .hold_mask = 0,
 167 -               .fixed_divider = 10),
 168 +               .fixed_divider = 10,
 169 +               .flags = CLK_SET_RATE_PARENT),
 170
 171         /* the clocks */
 172