drivers/clk/clk-oxnas.c

   1 /*
   2  * Copyright (C) 2010 Broadcom
   3  * Copyright (C) 2012 Stephen Warren
   4  * Copyright (C) 2016 Neil Armstrong <narmstrong@baylibre.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <linux/clk-provider.h>
  20 #include <linux/kernel.h>
  21 #include <linux/module.h>
  22 #include <linux/of.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/stringify.h>
  25 #include <linux/regmap.h>
  26 #include <linux/mfd/syscon.h>
  27
  28 /* Standard regmap gate clocks */
  29 struct clk_oxnas {
  30         struct clk_hw hw;
  31         signed char bit;
  32         struct regmap *regmap;
  33 };
  34
  35 /* Regmap offsets */
  36 #define CLK_STAT_REGOFFSET      0x24
  37 #define CLK_SET_REGOFFSET       0x2c
  38 #define CLK_CLR_REGOFFSET       0x30
  39
  40 static inline struct clk_oxnas *to_clk_oxnas(struct clk_hw *hw)
  41 {
  42         return container_of(hw, struct clk_oxnas, hw);
  43 }
  44
  45 static int oxnas_clk_is_enabled(struct clk_hw *hw)
  46 {
  47         struct clk_oxnas *std = to_clk_oxnas(hw);
  48         int ret;
  49         unsigned int val;
  50
  51         ret = regmap_read(std->regmap, CLK_STAT_REGOFFSET, &val);
  52         if (ret < 0)
  53                 return ret;
  54
  55         return val & BIT(std->bit);
  56 }
  57
  58 static int oxnas_clk_enable(struct clk_hw *hw)
  59 {
  60         struct clk_oxnas *std = to_clk_oxnas(hw);
  61
  62         regmap_write(std->regmap, CLK_SET_REGOFFSET, BIT(std->bit));
  63
  64         return 0;
  65 }
  66
  67 static void oxnas_clk_disable(struct clk_hw *hw)
  68 {
  69         struct clk_oxnas *std = to_clk_oxnas(hw);
  70
  71         regmap_write(std->regmap, CLK_CLR_REGOFFSET, BIT(std->bit));
  72 }
  73
  74 static const struct clk_ops oxnas_clk_ops = {
  75         .enable = oxnas_clk_enable,
  76         .disable = oxnas_clk_disable,
  77         .is_enabled = oxnas_clk_is_enabled,
  78 };
  79
  80 static const char *const oxnas_clk_parents[] = {
  81         "oscillator",
  82 };
  83
  84 static const char *const eth_parents[] = {
  85         "gmacclk",
  86 };
  87
  88 #define DECLARE_STD_CLKP(__clk, __parent)                       \
  89 static const struct clk_init_data clk_##__clk##_init = {        \
  90         .name = __stringify(__clk),                             \
  91         .ops = &oxnas_clk_ops,                                  \
  92         .parent_names = __parent,                               \
  93         .num_parents = ARRAY_SIZE(__parent),                    \
  94 }
  95
  96 #define DECLARE_STD_CLK(__clk) DECLARE_STD_CLKP(__clk, oxnas_clk_parents)
  97
  98 /* Hardware Bit - Clock association */
  99 struct clk_oxnas_init_data {
 100         unsigned long bit;
 101         const struct clk_init_data *clk_init;
 102 };
 103
 104 /* Clk init data declaration */
 105 DECLARE_STD_CLK(leon);
 106 DECLARE_STD_CLK(dma_sgdma);
 107 DECLARE_STD_CLK(cipher);
 108 DECLARE_STD_CLK(sata);
 109 DECLARE_STD_CLK(audio);
 110 DECLARE_STD_CLK(usbmph);
 111 DECLARE_STD_CLKP(etha, eth_parents);
 112 DECLARE_STD_CLK(pciea);
 113 DECLARE_STD_CLK(nand);
 114
 115 /* Table index is clock indice */
 116 static const struct clk_oxnas_init_data clk_oxnas_init[] = {
 117         [0] = {0, &clk_leon_init},
 118         [1] = {1, &clk_dma_sgdma_init},
 119         [2] = {2, &clk_cipher_init},
 120         /* Skip & Do not touch to DDR clock */
 121         [3] = {4, &clk_sata_init},
 122         [4] = {5, &clk_audio_init},
 123         [5] = {6, &clk_usbmph_init},
 124         [6] = {7, &clk_etha_init},
 125         [7] = {8, &clk_pciea_init},
 126         [8] = {9, &clk_nand_init},
 127 };
 128
 129 struct clk_oxnas_data {
 130         struct clk_oxnas clk_oxnas[ARRAY_SIZE(clk_oxnas_init)];
 131         struct clk_onecell_data onecell_data[ARRAY_SIZE(clk_oxnas_init)];
 132         struct clk *clks[ARRAY_SIZE(clk_oxnas_init)];
 133 };
 134
 135 static int oxnas_stdclk_probe(struct platform_device *pdev)
 136 {
 137         struct device_node *np = pdev->dev.of_node;
 138         struct clk_oxnas_data *clk_oxnas;
 139         struct regmap *regmap;
 140         int i;
 141
 142         clk_oxnas = devm_kzalloc(&pdev->dev, sizeof(*clk_oxnas), GFP_KERNEL);
 143         if (!clk_oxnas)
 144                 return -ENOMEM;
 145
 146         regmap = syscon_node_to_regmap(of_get_parent(np));
 147         if (!regmap) {
 148                 dev_err(&pdev->dev, "failed to have parent regmap\n");
 149                 return -EINVAL;
 150         }
 151
 152         for (i = 0; i < ARRAY_SIZE(clk_oxnas_init); i++) {
 153                 struct clk_oxnas *_clk;
 154
 155                 _clk = &clk_oxnas->clk_oxnas[i];
 156                 _clk->bit = clk_oxnas_init[i].bit;
 157                 _clk->hw.init = clk_oxnas_init[i].clk_init;
 158                 _clk->regmap = regmap;
 159
 160                 clk_oxnas->clks[i] =
 161                         devm_clk_register(&pdev->dev, &_clk->hw);
 162                 if (WARN_ON(IS_ERR(clk_oxnas->clks[i])))
 163                         return PTR_ERR(clk_oxnas->clks[i]);
 164         }
 165
 166         clk_oxnas->onecell_data->clks = clk_oxnas->clks;
 167         clk_oxnas->onecell_data->clk_num = ARRAY_SIZE(clk_oxnas_init);
 168
 169         return of_clk_add_provider(np, of_clk_src_onecell_get,
 170                                    clk_oxnas->onecell_data);
 171 }
 172
 173 static int oxnas_stdclk_remove(struct platform_device *pdev)
 174 {
 175         of_clk_del_provider(pdev->dev.of_node);
 176
 177         return 0;
 178 }
 179
 180 static const struct of_device_id oxnas_stdclk_dt_ids[] = {
 181         { .compatible = "oxsemi,ox810se-stdclk" },
 182         { }
 183 };
 184 MODULE_DEVICE_TABLE(of, oxnas_stdclk_dt_ids);
 185
 186 static struct platform_driver oxnas_stdclk_driver = {
 187         .probe = oxnas_stdclk_probe,
 188         .remove = oxnas_stdclk_remove,
 189         .driver = {
 190                 .name = "oxnas-stdclk",
 191                 .of_match_table = oxnas_stdclk_dt_ids,
 192         },
 193 };
 194
 195 module_platform_driver(oxnas_stdclk_driver);