LXR linux/drivers/clk/sunxi-ng/ccu

   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
  16static 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
  38static 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
  45static 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
  52static 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
  59static 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);
  75
  76        if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
  77                val /= cd->fixed_post_div;
  78
  79        return val;
  80}
  81
  82static 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
  91static 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
 121static 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
 128static 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
 135const 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};
 147