drivers/clk/sunxi/clk-a10-pll2.c

   1 /*
   2  * Copyright 2013 Emilio López
   3  * Emilio López <emilio@elopez.com.ar>
   4  *
   5  * Copyright 2015 Maxime Ripard
   6  * Maxime Ripard <maxime.ripard@free-electrons.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  */
  18
  19 #include <linux/clk-provider.h>
  20 #include <linux/of.h>
  21 #include <linux/of_address.h>
  22 #include <linux/slab.h>
  23
  24 #include <dt-bindings/clock/sun4i-a10-pll2.h>
  25
  26 #define SUN4I_PLL2_ENABLE               31
  27
  28 #define SUN4I_PLL2_PRE_DIV_SHIFT        0
  29 #define SUN4I_PLL2_PRE_DIV_WIDTH        5
  30 #define SUN4I_PLL2_PRE_DIV_MASK         GENMASK(SUN4I_PLL2_PRE_DIV_WIDTH - 1, 0)
  31
  32 #define SUN4I_PLL2_N_SHIFT              8
  33 #define SUN4I_PLL2_N_WIDTH              7
  34 #define SUN4I_PLL2_N_MASK               GENMASK(SUN4I_PLL2_N_WIDTH - 1, 0)
  35
  36 #define SUN4I_PLL2_POST_DIV_SHIFT       26
  37 #define SUN4I_PLL2_POST_DIV_WIDTH       4
  38 #define SUN4I_PLL2_POST_DIV_MASK        GENMASK(SUN4I_PLL2_POST_DIV_WIDTH - 1, 0)
  39
  40 #define SUN4I_PLL2_POST_DIV_VALUE       4
  41
  42 #define SUN4I_PLL2_OUTPUTS              4
  43
  44 static DEFINE_SPINLOCK(sun4i_a10_pll2_lock);
  45
  46 static void __init sun4i_pll2_setup(struct device_node *node,
  47                                     int post_div_offset)
  48 {
  49         const char *clk_name = node->name, *parent;
  50         struct clk **clks, *base_clk, *prediv_clk;
  51         struct clk_onecell_data *clk_data;
  52         struct clk_multiplier *mult;
  53         struct clk_gate *gate;
  54         void __iomem *reg;
  55         u32 val;
  56
  57         reg = of_io_request_and_map(node, 0, of_node_full_name(node));
  58         if (IS_ERR(reg))
  59                 return;
  60
  61         clk_data = kzalloc(sizeof(*clk_data), GFP_KERNEL);
  62         if (!clk_data)
  63                 goto err_unmap;
  64
  65         clks = kcalloc(SUN4I_PLL2_OUTPUTS, sizeof(struct clk *), GFP_KERNEL);
  66         if (!clks)
  67                 goto err_free_data;
  68
  69         parent = of_clk_get_parent_name(node, 0);
  70         prediv_clk = clk_register_divider(NULL, "pll2-prediv",
  71                                           parent, 0, reg,
  72                                           SUN4I_PLL2_PRE_DIV_SHIFT,
  73                                           SUN4I_PLL2_PRE_DIV_WIDTH,
  74                                           CLK_DIVIDER_ONE_BASED | CLK_DIVIDER_ALLOW_ZERO,
  75                                           &sun4i_a10_pll2_lock);
  76         if (!prediv_clk) {
  77                 pr_err("Couldn't register the prediv clock\n");
  78                 goto err_free_array;
  79         }
  80
  81         /* Setup the gate part of the PLL2 */
  82         gate = kzalloc(sizeof(struct clk_gate), GFP_KERNEL);
  83         if (!gate)
  84                 goto err_unregister_prediv;
  85
  86         gate->reg = reg;
  87         gate->bit_idx = SUN4I_PLL2_ENABLE;
  88         gate->lock = &sun4i_a10_pll2_lock;
  89
  90         /* Setup the multiplier part of the PLL2 */
  91         mult = kzalloc(sizeof(struct clk_multiplier), GFP_KERNEL);
  92         if (!mult)
  93                 goto err_free_gate;
  94
  95         mult->reg = reg;
  96         mult->shift = SUN4I_PLL2_N_SHIFT;
  97         mult->width = 7;
  98         mult->flags = CLK_MULTIPLIER_ZERO_BYPASS |
  99                         CLK_MULTIPLIER_ROUND_CLOSEST;
 100         mult->lock = &sun4i_a10_pll2_lock;
 101
 102         parent = __clk_get_name(prediv_clk);
 103         base_clk = clk_register_composite(NULL, "pll2-base",
 104                                           &parent, 1,
 105                                           NULL, NULL,
 106                                           &mult->hw, &clk_multiplier_ops,
 107                                           &gate->hw, &clk_gate_ops,
 108                                           CLK_SET_RATE_PARENT);
 109         if (!base_clk) {
 110                 pr_err("Couldn't register the base multiplier clock\n");
 111                 goto err_free_multiplier;
 112         }
 113
 114         parent = __clk_get_name(base_clk);
 115
 116         /*
 117          * PLL2-1x
 118          *
 119          * This is supposed to have a post divider, but we won't need
 120          * to use it, we just need to initialise it to 4, and use a
 121          * fixed divider.
 122          */
 123         val = readl(reg);
 124         val &= ~(SUN4I_PLL2_POST_DIV_MASK << SUN4I_PLL2_POST_DIV_SHIFT);
 125         val |= (SUN4I_PLL2_POST_DIV_VALUE - post_div_offset) << SUN4I_PLL2_POST_DIV_SHIFT;
 126         writel(val, reg);
 127
 128         of_property_read_string_index(node, "clock-output-names",
 129                                       SUN4I_A10_PLL2_1X, &clk_name);
 130         clks[SUN4I_A10_PLL2_1X] = clk_register_fixed_factor(NULL, clk_name,
 131                                                             parent,
 132                                                             CLK_SET_RATE_PARENT,
 133                                                             1,
 134                                                             SUN4I_PLL2_POST_DIV_VALUE);
 135         WARN_ON(IS_ERR(clks[SUN4I_A10_PLL2_1X]));
 136
 137         /*
 138          * PLL2-2x
 139          *
 140          * This clock doesn't use the post divider, and really is just
 141          * a fixed divider from the PLL2 base clock.
 142          */
 143         of_property_read_string_index(node, "clock-output-names",
 144                                       SUN4I_A10_PLL2_2X, &clk_name);
 145         clks[SUN4I_A10_PLL2_2X] = clk_register_fixed_factor(NULL, clk_name,
 146                                                             parent,
 147                                                             CLK_SET_RATE_PARENT,
 148                                                             1, 2);
 149         WARN_ON(IS_ERR(clks[SUN4I_A10_PLL2_2X]));
 150
 151         /* PLL2-4x */
 152         of_property_read_string_index(node, "clock-output-names",
 153                                       SUN4I_A10_PLL2_4X, &clk_name);
 154         clks[SUN4I_A10_PLL2_4X] = clk_register_fixed_factor(NULL, clk_name,
 155                                                             parent,
 156                                                             CLK_SET_RATE_PARENT,
 157                                                             1, 1);
 158         WARN_ON(IS_ERR(clks[SUN4I_A10_PLL2_4X]));
 159
 160         /* PLL2-8x */
 161         of_property_read_string_index(node, "clock-output-names",
 162                                       SUN4I_A10_PLL2_8X, &clk_name);
 163         clks[SUN4I_A10_PLL2_8X] = clk_register_fixed_factor(NULL, clk_name,
 164                                                             parent,
 165                                                             CLK_SET_RATE_PARENT,
 166                                                             2, 1);
 167         WARN_ON(IS_ERR(clks[SUN4I_A10_PLL2_8X]));
 168
 169         clk_data->clks = clks;
 170         clk_data->clk_num = SUN4I_PLL2_OUTPUTS;
 171         of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
 172
 173         return;
 174
 175 err_free_multiplier:
 176         kfree(mult);
 177 err_free_gate:
 178         kfree(gate);
 179 err_unregister_prediv:
 180         clk_unregister_divider(prediv_clk);
 181 err_free_array:
 182         kfree(clks);
 183 err_free_data:
 184         kfree(clk_data);
 185 err_unmap:
 186         iounmap(reg);
 187 }
 188
 189 static void __init sun4i_a10_pll2_setup(struct device_node *node)
 190 {
 191         sun4i_pll2_setup(node, 0);
 192 }
 193
 194 CLK_OF_DECLARE(sun4i_a10_pll2, "allwinner,sun4i-a10-pll2-clk",
 195                sun4i_a10_pll2_setup);
 196
 197 static void __init sun5i_a13_pll2_setup(struct device_node *node)
 198 {
 199         sun4i_pll2_setup(node, 1);
 200 }
 201
 202 CLK_OF_DECLARE(sun5i_a13_pll2, "allwinner,sun5i-a13-pll2-clk",
 203                sun5i_a13_pll2_setup);