1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Amlogic Meson SDHC clock controller
4  *
5  * Copyright (C) 2020 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
6  */
7 
8 #include <linux/clk.h>
9 #include <linux/clk-provider.h>
10 #include <linux/device.h>
11 #include <linux/platform_device.h>
12 
13 #include "meson-mx-sdhc.h"
14 
15 #define MESON_SDHC_NUM_BUILTIN_CLKS	6
16 
17 struct meson_mx_sdhc_clkc {
18 	struct clk_mux			src_sel;
19 	struct clk_divider		div;
20 	struct clk_gate			mod_clk_en;
21 	struct clk_gate			tx_clk_en;
22 	struct clk_gate			rx_clk_en;
23 	struct clk_gate			sd_clk_en;
24 };
25 
26 static const struct clk_parent_data meson_mx_sdhc_src_sel_parents[4] = {
27 	{ .fw_name = "clkin0" },
28 	{ .fw_name = "clkin1" },
29 	{ .fw_name = "clkin2" },
30 	{ .fw_name = "clkin3" },
31 };
32 
33 static const struct clk_div_table meson_mx_sdhc_div_table[] = {
34 	{ .div = 6, .val = 5, },
35 	{ .div = 8, .val = 7, },
36 	{ .div = 9, .val = 8, },
37 	{ .div = 10, .val = 9, },
38 	{ .div = 12, .val = 11, },
39 	{ .div = 16, .val = 15, },
40 	{ .div = 18, .val = 17, },
41 	{ .div = 34, .val = 33, },
42 	{ .div = 142, .val = 141, },
43 	{ .div = 850, .val = 849, },
44 	{ .div = 2126, .val = 2125, },
45 	{ .div = 4096, .val = 4095, },
46 	{ /* sentinel */ }
47 };
48 
49 static int meson_mx_sdhc_clk_hw_register(struct device *dev,
50 					 const char *name_suffix,
51 					 const struct clk_parent_data *parents,
52 					 unsigned int num_parents,
53 					 const struct clk_ops *ops,
54 					 struct clk_hw *hw)
55 {
56 	struct clk_init_data init = { };
57 	char clk_name[32];
58 
59 	snprintf(clk_name, sizeof(clk_name), "%s#%s", dev_name(dev),
60 		 name_suffix);
61 
62 	init.name = clk_name;
63 	init.ops = ops;
64 	init.flags = CLK_SET_RATE_PARENT;
65 	init.parent_data = parents;
66 	init.num_parents = num_parents;
67 
68 	hw->init = &init;
69 
70 	return devm_clk_hw_register(dev, hw);
71 }
72 
73 static int meson_mx_sdhc_gate_clk_hw_register(struct device *dev,
74 					      const char *name_suffix,
75 					      struct clk_hw *parent,
76 					      struct clk_hw *hw)
77 {
78 	struct clk_parent_data parent_data = { .hw = parent };
79 
80 	return meson_mx_sdhc_clk_hw_register(dev, name_suffix, &parent_data, 1,
81 					     &clk_gate_ops, hw);
82 }
83 
84 int meson_mx_sdhc_register_clkc(struct device *dev, void __iomem *base,
85 				struct clk_bulk_data *clk_bulk_data)
86 {
87 	struct clk_parent_data div_parent = { };
88 	struct meson_mx_sdhc_clkc *clkc_data;
89 	int ret;
90 
91 	clkc_data = devm_kzalloc(dev, sizeof(*clkc_data), GFP_KERNEL);
92 	if (!clkc_data)
93 		return -ENOMEM;
94 
95 	clkc_data->src_sel.reg = base + MESON_SDHC_CLKC;
96 	clkc_data->src_sel.mask = 0x3;
97 	clkc_data->src_sel.shift = 16;
98 	ret = meson_mx_sdhc_clk_hw_register(dev, "src_sel",
99 					    meson_mx_sdhc_src_sel_parents, 4,
100 					    &clk_mux_ops,
101 					    &clkc_data->src_sel.hw);
102 	if (ret)
103 		return ret;
104 
105 	clkc_data->div.reg = base + MESON_SDHC_CLKC;
106 	clkc_data->div.shift = 0;
107 	clkc_data->div.width = 12;
108 	clkc_data->div.table = meson_mx_sdhc_div_table;
109 	div_parent.hw = &clkc_data->src_sel.hw;
110 	ret = meson_mx_sdhc_clk_hw_register(dev, "div", &div_parent, 1,
111 					    &clk_divider_ops,
112 					    &clkc_data->div.hw);
113 	if (ret)
114 		return ret;
115 
116 	clkc_data->mod_clk_en.reg = base + MESON_SDHC_CLKC;
117 	clkc_data->mod_clk_en.bit_idx = 15;
118 	ret = meson_mx_sdhc_gate_clk_hw_register(dev, "mod_clk_on",
119 						 &clkc_data->div.hw,
120 						 &clkc_data->mod_clk_en.hw);
121 	if (ret)
122 		return ret;
123 
124 	clkc_data->tx_clk_en.reg = base + MESON_SDHC_CLKC;
125 	clkc_data->tx_clk_en.bit_idx = 14;
126 	ret = meson_mx_sdhc_gate_clk_hw_register(dev, "tx_clk_on",
127 						 &clkc_data->div.hw,
128 						 &clkc_data->tx_clk_en.hw);
129 	if (ret)
130 		return ret;
131 
132 	clkc_data->rx_clk_en.reg = base + MESON_SDHC_CLKC;
133 	clkc_data->rx_clk_en.bit_idx = 13;
134 	ret = meson_mx_sdhc_gate_clk_hw_register(dev, "rx_clk_on",
135 						 &clkc_data->div.hw,
136 						 &clkc_data->rx_clk_en.hw);
137 	if (ret)
138 		return ret;
139 
140 	clkc_data->sd_clk_en.reg = base + MESON_SDHC_CLKC;
141 	clkc_data->sd_clk_en.bit_idx = 12;
142 	ret = meson_mx_sdhc_gate_clk_hw_register(dev, "sd_clk_on",
143 						 &clkc_data->div.hw,
144 						 &clkc_data->sd_clk_en.hw);
145 	if (ret)
146 		return ret;
147 
148 	/*
149 	 * TODO: Replace clk_hw.clk with devm_clk_hw_get_clk() once that is
150 	 * available.
151 	 */
152 	clk_bulk_data[0].clk = clkc_data->mod_clk_en.hw.clk;
153 	clk_bulk_data[1].clk = clkc_data->sd_clk_en.hw.clk;
154 	clk_bulk_data[2].clk = clkc_data->tx_clk_en.hw.clk;
155 	clk_bulk_data[3].clk = clkc_data->rx_clk_en.hw.clk;
156 
157 	return 0;
158 }
159