drivers/clk/sunxi-ng/ccu_mult.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2016 Maxime Ripard
   4  * Maxime Ripard <maxime.ripard@free-electrons.com>
   5  */
   6
   7 #include <linux/clk-provider.h>
   8 #include <linux/io.h>
   9
  10 #include "ccu_gate.h"
  11 #include "ccu_mult.h"
  12
  13 struct _ccu_mult {
  14         unsigned long   mult, min, max;
  15 };
  16
  17 static void ccu_mult_find_best(unsigned long parent, unsigned long rate,
  18                                struct _ccu_mult *mult)
  19 {
  20         int _mult;
  21
  22         _mult = rate / parent;
  23         if (_mult < mult->min)
  24                 _mult = mult->min;
  25
  26         if (_mult > mult->max)
  27                 _mult = mult->max;
  28
  29         mult->mult = _mult;
  30 }
  31
  32 static unsigned long ccu_mult_round_rate(struct ccu_mux_internal *mux,
  33                                          struct clk_hw *parent,
  34                                          unsigned long *parent_rate,
  35                                          unsigned long rate,
  36                                          void *data)
  37 {
  38         struct ccu_mult *cm = data;
  39         struct _ccu_mult _cm;
  40
  41         _cm.min = cm->mult.min;
  42
  43         if (cm->mult.max)
  44                 _cm.max = cm->mult.max;
  45         else
  46                 _cm.max = (1 << cm->mult.width) + cm->mult.offset - 1;
  47
  48         ccu_mult_find_best(*parent_rate, rate, &_cm);
  49
  50         return *parent_rate * _cm.mult;
  51 }
  52
  53 static void ccu_mult_disable(struct clk_hw *hw)
  54 {
  55         struct ccu_mult *cm = hw_to_ccu_mult(hw);
  56
  57         return ccu_gate_helper_disable(&cm->common, cm->enable);
  58 }
  59
  60 static int ccu_mult_enable(struct clk_hw *hw)
  61 {
  62         struct ccu_mult *cm = hw_to_ccu_mult(hw);
  63
  64         return ccu_gate_helper_enable(&cm->common, cm->enable);
  65 }
  66
  67 static int ccu_mult_is_enabled(struct clk_hw *hw)
  68 {
  69         struct ccu_mult *cm = hw_to_ccu_mult(hw);
  70
  71         return ccu_gate_helper_is_enabled(&cm->common, cm->enable);
  72 }
  73
  74 static unsigned long ccu_mult_recalc_rate(struct clk_hw *hw,
  75                                         unsigned long parent_rate)
  76 {
  77         struct ccu_mult *cm = hw_to_ccu_mult(hw);
  78         unsigned long val;
  79         u32 reg;
  80
  81         if (ccu_frac_helper_is_enabled(&cm->common, &cm->frac))
  82                 return ccu_frac_helper_read_rate(&cm->common, &cm->frac);
  83
  84         reg = readl(cm->common.base + cm->common.reg);
  85         val = reg >> cm->mult.shift;
  86         val &= (1 << cm->mult.width) - 1;
  87
  88         parent_rate = ccu_mux_helper_apply_prediv(&cm->common, &cm->mux, -1,
  89                                                   parent_rate);
  90
  91         return parent_rate * (val + cm->mult.offset);
  92 }
  93
  94 static int ccu_mult_determine_rate(struct clk_hw *hw,
  95                                 struct clk_rate_request *req)
  96 {
  97         struct ccu_mult *cm = hw_to_ccu_mult(hw);
  98
  99         return ccu_mux_helper_determine_rate(&cm->common, &cm->mux,
 100                                              req, ccu_mult_round_rate, cm);
 101 }
 102
 103 static int ccu_mult_set_rate(struct clk_hw *hw, unsigned long rate,
 104                            unsigned long parent_rate)
 105 {
 106         struct ccu_mult *cm = hw_to_ccu_mult(hw);
 107         struct _ccu_mult _cm;
 108         unsigned long flags;
 109         u32 reg;
 110
 111         if (ccu_frac_helper_has_rate(&cm->common, &cm->frac, rate)) {
 112                 ccu_frac_helper_enable(&cm->common, &cm->frac);
 113
 114                 return ccu_frac_helper_set_rate(&cm->common, &cm->frac,
 115                                                 rate, cm->lock);
 116         } else {
 117                 ccu_frac_helper_disable(&cm->common, &cm->frac);
 118         }
 119
 120         parent_rate = ccu_mux_helper_apply_prediv(&cm->common, &cm->mux, -1,
 121                                                   parent_rate);
 122
 123         _cm.min = cm->mult.min;
 124
 125         if (cm->mult.max)
 126                 _cm.max = cm->mult.max;
 127         else
 128                 _cm.max = (1 << cm->mult.width) + cm->mult.offset - 1;
 129
 130         ccu_mult_find_best(parent_rate, rate, &_cm);
 131
 132         spin_lock_irqsave(cm->common.lock, flags);
 133
 134         reg = readl(cm->common.base + cm->common.reg);
 135         reg &= ~GENMASK(cm->mult.width + cm->mult.shift - 1, cm->mult.shift);
 136         reg |= ((_cm.mult - cm->mult.offset) << cm->mult.shift);
 137
 138         writel(reg, cm->common.base + cm->common.reg);
 139
 140         spin_unlock_irqrestore(cm->common.lock, flags);
 141
 142         ccu_helper_wait_for_lock(&cm->common, cm->lock);
 143
 144         return 0;
 145 }
 146
 147 static u8 ccu_mult_get_parent(struct clk_hw *hw)
 148 {
 149         struct ccu_mult *cm = hw_to_ccu_mult(hw);
 150
 151         return ccu_mux_helper_get_parent(&cm->common, &cm->mux);
 152 }
 153
 154 static int ccu_mult_set_parent(struct clk_hw *hw, u8 index)
 155 {
 156         struct ccu_mult *cm = hw_to_ccu_mult(hw);
 157
 158         return ccu_mux_helper_set_parent(&cm->common, &cm->mux, index);
 159 }
 160
 161 const struct clk_ops ccu_mult_ops = {
 162         .disable        = ccu_mult_disable,
 163         .enable         = ccu_mult_enable,
 164         .is_enabled     = ccu_mult_is_enabled,
 165
 166         .get_parent     = ccu_mult_get_parent,
 167         .set_parent     = ccu_mult_set_parent,
 168
 169         .determine_rate = ccu_mult_determine_rate,
 170         .recalc_rate    = ccu_mult_recalc_rate,
 171         .set_rate       = ccu_mult_set_rate,
 172 };