target/linux/sunxi/patches-3.13/120-clk-sunxi-mod0.patch

   1 From bdc913d1ef5143a8728ae414fcb90f9ed87a58da Mon Sep 17 00:00:00 2001
   2 From: =?UTF-8?q?Emilio=20L=C3=B3pez?= <emilio@elopez.com.ar>
   3 Date: Mon, 23 Dec 2013 00:32:39 -0300
   4 Subject: [PATCH] clk: sunxi: mod0 support
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 This commit implements support for the "module 0" type of clocks, as
  10 used by MMC, IR, NAND, SATA and other components.
  11
  12 Signed-off-by: Emilio López <emilio@elopez.com.ar>
  13 Acked-by: Mike Turquette <mturquette@linaro.org>
  14 ---
  15  Documentation/devicetree/bindings/clock/sunxi.txt |  5 +-
  16  drivers/clk/sunxi/clk-sunxi.c                     | 57 +++++++++++++++++++++++
  17  2 files changed, 61 insertions(+), 1 deletion(-)
  18
  19 --- a/Documentation/devicetree/bindings/clock/sunxi.txt
  20 +++ b/Documentation/devicetree/bindings/clock/sunxi.txt
  21 @@ -35,10 +35,13 @@ Required properties:
  22         "allwinner,sun7i-a20-apb1-gates-clk" - for the APB1 gates on A20
  23         "allwinner,sun6i-a31-apb2-div-clk" - for the APB2 gates on A31
  24         "allwinner,sun6i-a31-apb2-gates-clk" - for the APB2 gates on A31
  25 +       "allwinner,sun4i-mod0-clk" - for the module 0 family of clocks
  26
  27  Required properties for all clocks:
  28  - reg : shall be the control register address for the clock.
  29 -- clocks : shall be the input parent clock(s) phandle for the clock
  30 +- clocks : shall be the input parent clock(s) phandle for the clock. For
  31 +       multiplexed clocks, the list order must match the hardware
  32 +       programming order.
  33  - #clock-cells : from common clock binding; shall be set to 0 except for
  34         "allwinner,*-gates-clk" where it shall be set to 1
  35
  36 --- a/drivers/clk/sunxi/clk-sunxi.c
  37 +++ b/drivers/clk/sunxi/clk-sunxi.c
  38 @@ -295,6 +295,47 @@ static void sun4i_get_apb1_factors(u32 *
  39
  40
  41  /**
  42 + * sun4i_get_mod0_factors() - calculates m, n factors for MOD0-style clocks
  43 + * MMC rate is calculated as follows
  44 + * rate = (parent_rate >> p) / (m + 1);
  45 + */
  46 +
  47 +static void sun4i_get_mod0_factors(u32 *freq, u32 parent_rate,
  48 +                                  u8 *n, u8 *k, u8 *m, u8 *p)
  49 +{
  50 +       u8 div, calcm, calcp;
  51 +
  52 +       /* These clocks can only divide, so we will never be able to achieve
  53 +        * frequencies higher than the parent frequency */
  54 +       if (*freq > parent_rate)
  55 +               *freq = parent_rate;
  56 +
  57 +       div = parent_rate / *freq;
  58 +
  59 +       if (div < 16)
  60 +               calcp = 0;
  61 +       else if (div / 2 < 16)
  62 +               calcp = 1;
  63 +       else if (div / 4 < 16)
  64 +               calcp = 2;
  65 +       else
  66 +               calcp = 3;
  67 +
  68 +       calcm = DIV_ROUND_UP(div, 1 << calcp);
  69 +
  70 +       *freq = (parent_rate >> calcp) / calcm;
  71 +
  72 +       /* we were called to round the frequency, we can now return */
  73 +       if (n == NULL)
  74 +               return;
  75 +
  76 +       *m = calcm - 1;
  77 +       *p = calcp;
  78 +}
  79 +
  80 +
  81 +
  82 +/**
  83   * sunxi_factors_clk_setup() - Setup function for factor clocks
  84   */
  85
  86 @@ -341,6 +382,14 @@ static struct clk_factors_config sun4i_a
  87         .pwidth = 2,
  88  };
  89
  90 +/* user manual says "n" but it's really "p" */
  91 +static struct clk_factors_config sun4i_mod0_config = {
  92 +       .mshift = 0,
  93 +       .mwidth = 4,
  94 +       .pshift = 16,
  95 +       .pwidth = 2,
  96 +};
  97 +
  98  static const struct factors_data sun4i_pll1_data __initconst = {
  99         .enable = 31,
 100         .table = &sun4i_pll1_config,
 101 @@ -364,6 +413,13 @@ static const struct factors_data sun4i_a
 102         .getter = sun4i_get_apb1_factors,
 103  };
 104
 105 +static const struct factors_data sun4i_mod0_data __initconst = {
 106 +       .enable = 31,
 107 +       .mux = 24,
 108 +       .table = &sun4i_mod0_config,
 109 +       .getter = sun4i_get_mod0_factors,
 110 +};
 111 +
 112  static struct clk * __init sunxi_factors_clk_setup(struct device_node *node,
 113                                                 const struct factors_data *data)
 114  {
 115 @@ -852,6 +908,7 @@ static const struct of_device_id clk_fac
 116         {.compatible = "allwinner,sun4i-pll1-clk", .data = &sun4i_pll1_data,},
 117         {.compatible = "allwinner,sun6i-a31-pll1-clk", .data = &sun6i_a31_pll1_data,},
 118         {.compatible = "allwinner,sun4i-apb1-clk", .data = &sun4i_apb1_data,},
 119 +       {.compatible = "allwinner,sun4i-mod0-clk", .data = &sun4i_mod0_data,},
 120         {}
 121  };
 122