1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * MStar MSC313 MPLL driver 4 * 5 * Copyright (C) 2020 Daniel Palmer <daniel@thingy.jp> 6 */ 7 8 #include <linux/platform_device.h> 9 #include <linux/of_address.h> 10 #include <linux/clk-provider.h> 11 #include <linux/regmap.h> 12 13 #define REG_CONFIG1 0x8 14 #define REG_CONFIG2 0xc 15 16 static const struct regmap_config msc313_mpll_regmap_config = { 17 .reg_bits = 16, 18 .val_bits = 16, 19 .reg_stride = 4, 20 }; 21 22 static const struct reg_field config1_loop_div_first = REG_FIELD(REG_CONFIG1, 8, 9); 23 static const struct reg_field config1_input_div_first = REG_FIELD(REG_CONFIG1, 4, 5); 24 static const struct reg_field config2_output_div_first = REG_FIELD(REG_CONFIG2, 12, 13); 25 static const struct reg_field config2_loop_div_second = REG_FIELD(REG_CONFIG2, 0, 7); 26 27 static const unsigned int output_dividers[] = { 28 2, 3, 4, 5, 6, 7, 10 29 }; 30 31 #define NUMOUTPUTS (ARRAY_SIZE(output_dividers) + 1) 32 33 struct msc313_mpll { 34 struct clk_hw clk_hw; 35 struct regmap_field *input_div; 36 struct regmap_field *loop_div_first; 37 struct regmap_field *loop_div_second; 38 struct regmap_field *output_div; 39 struct clk_hw_onecell_data *clk_data; 40 }; 41 42 #define to_mpll(_hw) container_of(_hw, struct msc313_mpll, clk_hw) 43 44 static unsigned long msc313_mpll_recalc_rate(struct clk_hw *hw, 45 unsigned long parent_rate) 46 { 47 struct msc313_mpll *mpll = to_mpll(hw); 48 unsigned int input_div, output_div, loop_first, loop_second; 49 unsigned long output_rate; 50 51 regmap_field_read(mpll->input_div, &input_div); 52 regmap_field_read(mpll->output_div, &output_div); 53 regmap_field_read(mpll->loop_div_first, &loop_first); 54 regmap_field_read(mpll->loop_div_second, &loop_second); 55 56 output_rate = parent_rate / (1 << input_div); 57 output_rate *= (1 << loop_first) * max(loop_second, 1U); 58 output_rate /= max(output_div, 1U); 59 60 return output_rate; 61 } 62 63 static const struct clk_ops msc313_mpll_ops = { 64 .recalc_rate = msc313_mpll_recalc_rate, 65 }; 66 67 static const struct clk_parent_data mpll_parent = { 68 .index = 0, 69 }; 70 71 static int msc313_mpll_probe(struct platform_device *pdev) 72 { 73 void __iomem *base; 74 struct msc313_mpll *mpll; 75 struct clk_init_data clk_init = { }; 76 struct device *dev = &pdev->dev; 77 struct regmap *regmap; 78 char *outputname; 79 struct clk_hw *divhw; 80 int ret, i; 81 82 mpll = devm_kzalloc(dev, sizeof(*mpll), GFP_KERNEL); 83 if (!mpll) 84 return -ENOMEM; 85 86 base = devm_platform_ioremap_resource(pdev, 0); 87 if (IS_ERR(base)) 88 return PTR_ERR(base); 89 90 regmap = devm_regmap_init_mmio(dev, base, &msc313_mpll_regmap_config); 91 if (IS_ERR(regmap)) 92 return PTR_ERR(regmap); 93 94 mpll->input_div = devm_regmap_field_alloc(dev, regmap, config1_input_div_first); 95 if (IS_ERR(mpll->input_div)) 96 return PTR_ERR(mpll->input_div); 97 mpll->output_div = devm_regmap_field_alloc(dev, regmap, config2_output_div_first); 98 if (IS_ERR(mpll->output_div)) 99 return PTR_ERR(mpll->output_div); 100 mpll->loop_div_first = devm_regmap_field_alloc(dev, regmap, config1_loop_div_first); 101 if (IS_ERR(mpll->loop_div_first)) 102 return PTR_ERR(mpll->loop_div_first); 103 mpll->loop_div_second = devm_regmap_field_alloc(dev, regmap, config2_loop_div_second); 104 if (IS_ERR(mpll->loop_div_second)) 105 return PTR_ERR(mpll->loop_div_second); 106 107 mpll->clk_data = devm_kzalloc(dev, struct_size(mpll->clk_data, hws, 108 ARRAY_SIZE(output_dividers)), GFP_KERNEL); 109 if (!mpll->clk_data) 110 return -ENOMEM; 111 112 clk_init.name = dev_name(dev); 113 clk_init.ops = &msc313_mpll_ops; 114 clk_init.parent_data = &mpll_parent; 115 clk_init.num_parents = 1; 116 mpll->clk_hw.init = &clk_init; 117 118 ret = devm_clk_hw_register(dev, &mpll->clk_hw); 119 if (ret) 120 return ret; 121 122 mpll->clk_data->num = NUMOUTPUTS; 123 mpll->clk_data->hws[0] = &mpll->clk_hw; 124 125 for (i = 0; i < ARRAY_SIZE(output_dividers); i++) { 126 outputname = devm_kasprintf(dev, GFP_KERNEL, "%s_div_%u", 127 clk_init.name, output_dividers[i]); 128 if (!outputname) 129 return -ENOMEM; 130 divhw = devm_clk_hw_register_fixed_factor(dev, outputname, 131 clk_init.name, 0, 1, output_dividers[i]); 132 if (IS_ERR(divhw)) 133 return PTR_ERR(divhw); 134 mpll->clk_data->hws[i + 1] = divhw; 135 } 136 137 platform_set_drvdata(pdev, mpll); 138 139 return devm_of_clk_add_hw_provider(&pdev->dev, of_clk_hw_onecell_get, 140 mpll->clk_data); 141 } 142 143 static const struct of_device_id msc313_mpll_of_match[] = { 144 { .compatible = "mstar,msc313-mpll", }, 145 {} 146 }; 147 148 static struct platform_driver msc313_mpll_driver = { 149 .driver = { 150 .name = "mstar-msc313-mpll", 151 .of_match_table = msc313_mpll_of_match, 152 }, 153 .probe = msc313_mpll_probe, 154 }; 155 builtin_platform_driver(msc313_mpll_driver); 156