drivers/clk/meson/vid-pll-div.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2018 BayLibre, SAS.
   4  * Author: Neil Armstrong <narmstrong@baylibre.com>
   5  */
   6
   7 #include <linux/clk-provider.h>
   8 #include <linux/module.h>
   9
  10 #include "clk-regmap.h"
  11 #include "vid-pll-div.h"
  12
  13 static inline struct meson_vid_pll_div_data *
  14 meson_vid_pll_div_data(struct clk_regmap *clk)
  15 {
  16         return (struct meson_vid_pll_div_data *)clk->data;
  17 }
  18
  19 /*
  20  * This vid_pll divided is a fully programmable fractionnal divider to
  21  * achieve complex video clock rates.
  22  *
  23  * Here are provided the commonly used fraction values provided by Amlogic.
  24  */
  25
  26 struct vid_pll_div {
  27         unsigned int shift_val;
  28         unsigned int shift_sel;
  29         unsigned int divider;
  30         unsigned int multiplier;
  31 };
  32
  33 #define VID_PLL_DIV(_val, _sel, _ft, _fb)                               \
  34         {                                                               \
  35                 .shift_val = (_val),                                    \
  36                 .shift_sel = (_sel),                                    \
  37                 .divider = (_ft),                                       \
  38                 .multiplier = (_fb),                                    \
  39         }
  40
  41 static const struct vid_pll_div vid_pll_div_table[] = {
  42         VID_PLL_DIV(0x0aaa, 0, 2, 1),   /* 2/1  => /2 */
  43         VID_PLL_DIV(0x5294, 2, 5, 2),   /* 5/2  => /2.5 */
  44         VID_PLL_DIV(0x0db6, 0, 3, 1),   /* 3/1  => /3 */
  45         VID_PLL_DIV(0x36cc, 1, 7, 2),   /* 7/2  => /3.5 */
  46         VID_PLL_DIV(0x6666, 2, 15, 4),  /* 15/4 => /3.75 */
  47         VID_PLL_DIV(0x0ccc, 0, 4, 1),   /* 4/1  => /4 */
  48         VID_PLL_DIV(0x739c, 2, 5, 1),   /* 5/1  => /5 */
  49         VID_PLL_DIV(0x0e38, 0, 6, 1),   /* 6/1  => /6 */
  50         VID_PLL_DIV(0x0000, 3, 25, 4),  /* 25/4 => /6.25 */
  51         VID_PLL_DIV(0x3c78, 1, 7, 1),   /* 7/1  => /7 */
  52         VID_PLL_DIV(0x78f0, 2, 15, 2),  /* 15/2 => /7.5 */
  53         VID_PLL_DIV(0x0fc0, 0, 12, 1),  /* 12/1 => /12 */
  54         VID_PLL_DIV(0x3f80, 1, 14, 1),  /* 14/1 => /14 */
  55         VID_PLL_DIV(0x7f80, 2, 15, 1),  /* 15/1 => /15 */
  56 };
  57
  58 #define to_meson_vid_pll_div(_hw) \
  59         container_of(_hw, struct meson_vid_pll_div, hw)
  60
  61 static const struct vid_pll_div *_get_table_val(unsigned int shift_val,
  62                                                 unsigned int shift_sel)
  63 {
  64         int i;
  65
  66         for (i = 0 ; i < ARRAY_SIZE(vid_pll_div_table) ; ++i) {
  67                 if (vid_pll_div_table[i].shift_val == shift_val &&
  68                     vid_pll_div_table[i].shift_sel == shift_sel)
  69                         return &vid_pll_div_table[i];
  70         }
  71
  72         return NULL;
  73 }
  74
  75 static unsigned long meson_vid_pll_div_recalc_rate(struct clk_hw *hw,
  76                                                    unsigned long parent_rate)
  77 {
  78         struct clk_regmap *clk = to_clk_regmap(hw);
  79         struct meson_vid_pll_div_data *pll_div = meson_vid_pll_div_data(clk);
  80         const struct vid_pll_div *div;
  81
  82         div = _get_table_val(meson_parm_read(clk->map, &pll_div->val),
  83                              meson_parm_read(clk->map, &pll_div->sel));
  84         if (!div || !div->divider) {
  85                 pr_debug("%s: Invalid config value for vid_pll_div\n", __func__);
  86                 return 0;
  87         }
  88
  89         return DIV_ROUND_UP_ULL(parent_rate * div->multiplier, div->divider);
  90 }
  91
  92 const struct clk_ops meson_vid_pll_div_ro_ops = {
  93         .recalc_rate    = meson_vid_pll_div_recalc_rate,
  94 };
  95 EXPORT_SYMBOL_GPL(meson_vid_pll_div_ro_ops);
  96
  97 MODULE_DESCRIPTION("Amlogic video pll divider driver");
  98 MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
  99 MODULE_LICENSE("GPL v2");