drivers/clk/sunxi-ng/ccu_mult.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_mult.h"
  15
  16 struct _ccu_mult {
  17         unsigned long   mult, min, max;
  18 };
  19
  20 static void ccu_mult_find_best(unsigned long parent, unsigned long rate,
  21                                struct _ccu_mult *mult)
  22 {
  23         int _mult;
  24
  25         _mult = rate / parent;
  26         if (_mult < mult->min)
  27                 _mult = mult->min;
  28
  29         if (_mult > mult->max)
  30                 _mult = mult->max;
  31
  32         mult->mult = _mult;
  33 }
  34
  35 static unsigned long ccu_mult_round_rate(struct ccu_mux_internal *mux,
  36                                         unsigned long parent_rate,
  37                                         unsigned long rate,
  38                                         void *data)
  39 {
  40         struct ccu_mult *cm = data;
  41         struct _ccu_mult _cm;
  42
  43         _cm.min = 1;
  44         _cm.max = 1 << cm->mult.width;
  45         ccu_mult_find_best(parent_rate, rate, &_cm);
  46
  47         return parent_rate * _cm.mult;
  48 }
  49
  50 static void ccu_mult_disable(struct clk_hw *hw)
  51 {
  52         struct ccu_mult *cm = hw_to_ccu_mult(hw);
  53
  54         return ccu_gate_helper_disable(&cm->common, cm->enable);
  55 }
  56
  57 static int ccu_mult_enable(struct clk_hw *hw)
  58 {
  59         struct ccu_mult *cm = hw_to_ccu_mult(hw);
  60
  61         return ccu_gate_helper_enable(&cm->common, cm->enable);
  62 }
  63
  64 static int ccu_mult_is_enabled(struct clk_hw *hw)
  65 {
  66         struct ccu_mult *cm = hw_to_ccu_mult(hw);
  67
  68         return ccu_gate_helper_is_enabled(&cm->common, cm->enable);
  69 }
  70
  71 static unsigned long ccu_mult_recalc_rate(struct clk_hw *hw,
  72                                         unsigned long parent_rate)
  73 {
  74         struct ccu_mult *cm = hw_to_ccu_mult(hw);
  75         unsigned long val;
  76         u32 reg;
  77
  78         reg = readl(cm->common.base + cm->common.reg);
  79         val = reg >> cm->mult.shift;
  80         val &= (1 << cm->mult.width) - 1;
  81
  82         ccu_mux_helper_adjust_parent_for_prediv(&cm->common, &cm->mux, -1,
  83                                                 &parent_rate);
  84
  85         return parent_rate * (val + 1);
  86 }
  87
  88 static int ccu_mult_determine_rate(struct clk_hw *hw,
  89                                 struct clk_rate_request *req)
  90 {
  91         struct ccu_mult *cm = hw_to_ccu_mult(hw);
  92
  93         return ccu_mux_helper_determine_rate(&cm->common, &cm->mux,
  94                                              req, ccu_mult_round_rate, cm);
  95 }
  96
  97 static int ccu_mult_set_rate(struct clk_hw *hw, unsigned long rate,
  98                            unsigned long parent_rate)
  99 {
 100         struct ccu_mult *cm = hw_to_ccu_mult(hw);
 101         struct _ccu_mult _cm;
 102         unsigned long flags;
 103         u32 reg;
 104
 105         ccu_mux_helper_adjust_parent_for_prediv(&cm->common, &cm->mux, -1,
 106                                                 &parent_rate);
 107
 108         _cm.min = cm->mult.min;
 109         _cm.max = 1 << cm->mult.width;
 110         ccu_mult_find_best(parent_rate, rate, &_cm);
 111
 112         spin_lock_irqsave(cm->common.lock, flags);
 113
 114         reg = readl(cm->common.base + cm->common.reg);
 115         reg &= ~GENMASK(cm->mult.width + cm->mult.shift - 1, cm->mult.shift);
 116
 117         writel(reg | ((_cm.mult - 1) << cm->mult.shift),
 118                cm->common.base + cm->common.reg);
 119
 120         spin_unlock_irqrestore(cm->common.lock, flags);
 121
 122         return 0;
 123 }
 124
 125 static u8 ccu_mult_get_parent(struct clk_hw *hw)
 126 {
 127         struct ccu_mult *cm = hw_to_ccu_mult(hw);
 128
 129         return ccu_mux_helper_get_parent(&cm->common, &cm->mux);
 130 }
 131
 132 static int ccu_mult_set_parent(struct clk_hw *hw, u8 index)
 133 {
 134         struct ccu_mult *cm = hw_to_ccu_mult(hw);
 135
 136         return ccu_mux_helper_set_parent(&cm->common, &cm->mux, index);
 137 }
 138
 139 const struct clk_ops ccu_mult_ops = {
 140         .disable        = ccu_mult_disable,
 141         .enable         = ccu_mult_enable,
 142         .is_enabled     = ccu_mult_is_enabled,
 143
 144         .get_parent     = ccu_mult_get_parent,
 145         .set_parent     = ccu_mult_set_parent,
 146
 147         .determine_rate = ccu_mult_determine_rate,
 148         .recalc_rate    = ccu_mult_recalc_rate,
 149         .set_rate       = ccu_mult_set_rate,
 150 };