drivers/clk/sunxi-ng/ccu_div.c

   1 /*
   2  * Copyright (C) 2016 Maxime Ripard
   3  * Maxime Ripard <maxime.ripard@free-electrons.com>
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License as
   7  * published by the Free Software Foundation; either version 2 of
   8  * the License, or (at your option) any later version.
   9  */
  10
  11 #include <linux/clk-provider.h>
  12
  13 #include "ccu_gate.h"
  14 #include "ccu_div.h"
  15
  16 static unsigned long ccu_div_round_rate(struct ccu_mux_internal *mux,
  17                                         struct clk_hw *parent,
  18                                         unsigned long *parent_rate,
  19                                         unsigned long rate,
  20                                         void *data)
  21 {
  22         struct ccu_div *cd = data;
  23
  24         if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
  25                 rate *= cd->fixed_post_div;
  26
  27         rate = divider_round_rate_parent(&cd->common.hw, parent,
  28                                          rate, parent_rate,
  29                                          cd->div.table, cd->div.width,
  30                                          cd->div.flags);
  31
  32         if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
  33                 rate /= cd->fixed_post_div;
  34
  35         return rate;
  36 }
  37
  38 static void ccu_div_disable(struct clk_hw *hw)
  39 {
  40         struct ccu_div *cd = hw_to_ccu_div(hw);
  41
  42         return ccu_gate_helper_disable(&cd->common, cd->enable);
  43 }
  44
  45 static int ccu_div_enable(struct clk_hw *hw)
  46 {
  47         struct ccu_div *cd = hw_to_ccu_div(hw);
  48
  49         return ccu_gate_helper_enable(&cd->common, cd->enable);
  50 }
  51
  52 static int ccu_div_is_enabled(struct clk_hw *hw)
  53 {
  54         struct ccu_div *cd = hw_to_ccu_div(hw);
  55
  56         return ccu_gate_helper_is_enabled(&cd->common, cd->enable);
  57 }
  58
  59 static unsigned long ccu_div_recalc_rate(struct clk_hw *hw,
  60                                         unsigned long parent_rate)
  61 {
  62         struct ccu_div *cd = hw_to_ccu_div(hw);
  63         unsigned long val;
  64         u32 reg;
  65
  66         reg = readl(cd->common.base + cd->common.reg);
  67         val = reg >> cd->div.shift;
  68         val &= (1 << cd->div.width) - 1;
  69
  70         parent_rate = ccu_mux_helper_apply_prediv(&cd->common, &cd->mux, -1,
  71                                                   parent_rate);
  72
  73         val = divider_recalc_rate(hw, parent_rate, val, cd->div.table,
  74                                   cd->div.flags, cd->div.width);
  75
  76         if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
  77                 val /= cd->fixed_post_div;
  78
  79         return val;
  80 }
  81
  82 static int ccu_div_determine_rate(struct clk_hw *hw,
  83                                 struct clk_rate_request *req)
  84 {
  85         struct ccu_div *cd = hw_to_ccu_div(hw);
  86
  87         return ccu_mux_helper_determine_rate(&cd->common, &cd->mux,
  88                                              req, ccu_div_round_rate, cd);
  89 }
  90
  91 static int ccu_div_set_rate(struct clk_hw *hw, unsigned long rate,
  92                            unsigned long parent_rate)
  93 {
  94         struct ccu_div *cd = hw_to_ccu_div(hw);
  95         unsigned long flags;
  96         unsigned long val;
  97         u32 reg;
  98
  99         parent_rate = ccu_mux_helper_apply_prediv(&cd->common, &cd->mux, -1,
 100                                                   parent_rate);
 101
 102         if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
 103                 rate *= cd->fixed_post_div;
 104
 105         val = divider_get_val(rate, parent_rate, cd->div.table, cd->div.width,
 106                               cd->div.flags);
 107
 108         spin_lock_irqsave(cd->common.lock, flags);
 109
 110         reg = readl(cd->common.base + cd->common.reg);
 111         reg &= ~GENMASK(cd->div.width + cd->div.shift - 1, cd->div.shift);
 112
 113         writel(reg | (val << cd->div.shift),
 114                cd->common.base + cd->common.reg);
 115
 116         spin_unlock_irqrestore(cd->common.lock, flags);
 117
 118         return 0;
 119 }
 120
 121 static u8 ccu_div_get_parent(struct clk_hw *hw)
 122 {
 123         struct ccu_div *cd = hw_to_ccu_div(hw);
 124
 125         return ccu_mux_helper_get_parent(&cd->common, &cd->mux);
 126 }
 127
 128 static int ccu_div_set_parent(struct clk_hw *hw, u8 index)
 129 {
 130         struct ccu_div *cd = hw_to_ccu_div(hw);
 131
 132         return ccu_mux_helper_set_parent(&cd->common, &cd->mux, index);
 133 }
 134
 135 const struct clk_ops ccu_div_ops = {
 136         .disable        = ccu_div_disable,
 137         .enable         = ccu_div_enable,
 138         .is_enabled     = ccu_div_is_enabled,
 139
 140         .get_parent     = ccu_div_get_parent,
 141         .set_parent     = ccu_div_set_parent,
 142
 143         .determine_rate = ccu_div_determine_rate,
 144         .recalc_rate    = ccu_div_recalc_rate,
 145         .set_rate       = ccu_div_set_rate,
 146 };