xref: /linux/drivers/clk/renesas/clk-sh73a0.c (revision da5b2ad1c2f18834cb1ce429e2e5a5cf5cbdf21b)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * sh73a0 Core CPG Clocks
4  *
5  * Copyright (C) 2014  Ulrich Hecht
6  */
7 
8 #include <linux/clk-provider.h>
9 #include <linux/clk/renesas.h>
10 #include <linux/init.h>
11 #include <linux/io.h>
12 #include <linux/kernel.h>
13 #include <linux/of.h>
14 #include <linux/of_address.h>
15 #include <linux/slab.h>
16 #include <linux/spinlock.h>
17 
18 struct sh73a0_cpg {
19 	struct clk_onecell_data data;
20 	spinlock_t lock;
21 };
22 
23 #define CPG_FRQCRA	0x00
24 #define CPG_FRQCRB	0x04
25 #define CPG_SD0CKCR	0x74
26 #define CPG_SD1CKCR	0x78
27 #define CPG_SD2CKCR	0x7c
28 #define CPG_PLLECR	0xd0
29 #define CPG_PLL0CR	0xd8
30 #define CPG_PLL1CR	0x28
31 #define CPG_PLL2CR	0x2c
32 #define CPG_PLL3CR	0xdc
33 #define CPG_CKSCR	0xc0
34 #define CPG_DSI0PHYCR	0x6c
35 #define CPG_DSI1PHYCR	0x70
36 
37 struct div4_clk {
38 	const char *name;
39 	const char *parent;
40 	unsigned int reg;
41 	unsigned int shift;
42 };
43 
44 static const struct div4_clk div4_clks[] = {
45 	{ "zg", "pll0", CPG_FRQCRA, 16 },
46 	{ "m3", "pll1", CPG_FRQCRA, 12 },
47 	{ "b",  "pll1", CPG_FRQCRA,  8 },
48 	{ "m1", "pll1", CPG_FRQCRA,  4 },
49 	{ "m2", "pll1", CPG_FRQCRA,  0 },
50 	{ "zx", "pll1", CPG_FRQCRB, 12 },
51 	{ "hp", "pll1", CPG_FRQCRB,  4 },
52 	{ NULL, NULL, 0, 0 },
53 };
54 
55 static const struct clk_div_table div4_div_table[] = {
56 	{ 0, 2 }, { 1, 3 }, { 2, 4 }, { 3, 6 }, { 4, 8 }, { 5, 12 },
57 	{ 6, 16 }, { 7, 18 }, { 8, 24 }, { 10, 36 }, { 11, 48 },
58 	{ 12, 7 }, { 0, 0 }
59 };
60 
61 static const struct clk_div_table z_div_table[] = {
62 	/* ZSEL == 0 */
63 	{ 0, 1 }, { 1, 1 }, { 2, 1 }, { 3, 1 }, { 4, 1 }, { 5, 1 },
64 	{ 6, 1 }, { 7, 1 }, { 8, 1 }, { 9, 1 }, { 10, 1 }, { 11, 1 },
65 	{ 12, 1 }, { 13, 1 }, { 14, 1 }, { 15, 1 },
66 	/* ZSEL == 1 */
67 	{ 16, 2 }, { 17, 3 }, { 18, 4 }, { 19, 6 }, { 20, 8 }, { 21, 12 },
68 	{ 22, 16 }, { 24, 24 }, { 27, 48 }, { 0, 0 }
69 };
70 
71 static struct clk * __init
72 sh73a0_cpg_register_clock(struct device_node *np, struct sh73a0_cpg *cpg,
73 			  void __iomem *base, const char *name)
74 {
75 	const struct clk_div_table *table = NULL;
76 	unsigned int shift, reg, width;
77 	const char *parent_name = NULL;
78 	unsigned int mult = 1;
79 	unsigned int div = 1;
80 
81 	if (!strcmp(name, "main")) {
82 		/* extal1, extal1_div2, extal2, extal2_div2 */
83 		u32 parent_idx = (readl(base + CPG_CKSCR) >> 28) & 3;
84 
85 		parent_name = of_clk_get_parent_name(np, parent_idx >> 1);
86 		div = (parent_idx & 1) + 1;
87 	} else if (!strncmp(name, "pll", 3)) {
88 		void __iomem *enable_reg = base;
89 		u32 enable_bit = name[3] - '0';
90 
91 		parent_name = "main";
92 		switch (enable_bit) {
93 		case 0:
94 			enable_reg += CPG_PLL0CR;
95 			break;
96 		case 1:
97 			enable_reg += CPG_PLL1CR;
98 			break;
99 		case 2:
100 			enable_reg += CPG_PLL2CR;
101 			break;
102 		case 3:
103 			enable_reg += CPG_PLL3CR;
104 			break;
105 		default:
106 			return ERR_PTR(-EINVAL);
107 		}
108 		if (readl(base + CPG_PLLECR) & BIT(enable_bit)) {
109 			mult = ((readl(enable_reg) >> 24) & 0x3f) + 1;
110 			/* handle CFG bit for PLL1 and PLL2 */
111 			if (enable_bit == 1 || enable_bit == 2)
112 				if (readl(enable_reg) & BIT(20))
113 					mult *= 2;
114 		}
115 	} else if (!strcmp(name, "dsi0phy") || !strcmp(name, "dsi1phy")) {
116 		u32 phy_no = name[3] - '0';
117 		void __iomem *dsi_reg = base +
118 			(phy_no ? CPG_DSI1PHYCR : CPG_DSI0PHYCR);
119 
120 		parent_name = phy_no ? "dsi1pck" : "dsi0pck";
121 		mult = readl(dsi_reg);
122 		if (!(mult & 0x8000))
123 			mult = 1;
124 		else
125 			mult = (mult & 0x3f) + 1;
126 	} else if (!strcmp(name, "z")) {
127 		parent_name = "pll0";
128 		table = z_div_table;
129 		reg = CPG_FRQCRB;
130 		shift = 24;
131 		width = 5;
132 	} else {
133 		const struct div4_clk *c;
134 
135 		for (c = div4_clks; c->name; c++) {
136 			if (!strcmp(name, c->name)) {
137 				parent_name = c->parent;
138 				table = div4_div_table;
139 				reg = c->reg;
140 				shift = c->shift;
141 				width = 4;
142 				break;
143 			}
144 		}
145 		if (!c->name)
146 			return ERR_PTR(-EINVAL);
147 	}
148 
149 	if (!table) {
150 		return clk_register_fixed_factor(NULL, name, parent_name, 0,
151 						 mult, div);
152 	} else {
153 		return clk_register_divider_table(NULL, name, parent_name, 0,
154 						  base + reg, shift, width, 0,
155 						  table, &cpg->lock);
156 	}
157 }
158 
159 static void __init sh73a0_cpg_clocks_init(struct device_node *np)
160 {
161 	struct sh73a0_cpg *cpg;
162 	void __iomem *base;
163 	struct clk **clks;
164 	unsigned int i;
165 	int num_clks;
166 
167 	num_clks = of_property_count_strings(np, "clock-output-names");
168 	if (num_clks < 0) {
169 		pr_err("%s: failed to count clocks\n", __func__);
170 		return;
171 	}
172 
173 	cpg = kzalloc(sizeof(*cpg), GFP_KERNEL);
174 	clks = kcalloc(num_clks, sizeof(*clks), GFP_KERNEL);
175 	if (cpg == NULL || clks == NULL) {
176 		/* We're leaking memory on purpose, there's no point in cleaning
177 		 * up as the system won't boot anyway.
178 		 */
179 		return;
180 	}
181 
182 	spin_lock_init(&cpg->lock);
183 
184 	cpg->data.clks = clks;
185 	cpg->data.clk_num = num_clks;
186 
187 	base = of_iomap(np, 0);
188 	if (WARN_ON(base == NULL))
189 		return;
190 
191 	/* Set SDHI clocks to a known state */
192 	writel(0x108, base + CPG_SD0CKCR);
193 	writel(0x108, base + CPG_SD1CKCR);
194 	writel(0x108, base + CPG_SD2CKCR);
195 
196 	for (i = 0; i < num_clks; ++i) {
197 		const char *name;
198 		struct clk *clk;
199 
200 		of_property_read_string_index(np, "clock-output-names", i,
201 					      &name);
202 
203 		clk = sh73a0_cpg_register_clock(np, cpg, base, name);
204 		if (IS_ERR(clk))
205 			pr_err("%s: failed to register %pOFn %s clock (%ld)\n",
206 			       __func__, np, name, PTR_ERR(clk));
207 		else
208 			cpg->data.clks[i] = clk;
209 	}
210 
211 	of_clk_add_provider(np, of_clk_src_onecell_get, &cpg->data);
212 }
213 CLK_OF_DECLARE(sh73a0_cpg_clks, "renesas,sh73a0-cpg-clocks",
214 	       sh73a0_cpg_clocks_init);
215