1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * r8a7779 Core CPG Clocks
4 *
5 * Copyright (C) 2013, 2014 Horms Solutions Ltd.
6 *
7 * Contact: Simon Horman <horms@verge.net.au>
8 */
9
10 #include <linux/clk-provider.h>
11 #include <linux/clk/renesas.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/of.h>
15 #include <linux/of_address.h>
16 #include <linux/slab.h>
17 #include <linux/spinlock.h>
18 #include <linux/soc/renesas/rcar-rst.h>
19
20 #include <dt-bindings/clock/r8a7779-clock.h>
21
22 #define CPG_NUM_CLOCKS (R8A7779_CLK_OUT + 1)
23
24 /* -----------------------------------------------------------------------------
25 * CPG Clock Data
26 */
27
28 /*
29 * MD1 = 1 MD1 = 0
30 * (PLLA = 1500) (PLLA = 1600)
31 * (MHz) (MHz)
32 *------------------------------------------------+--------------------
33 * clkz 1000 (2/3) 800 (1/2)
34 * clkzs 250 (1/6) 200 (1/8)
35 * clki 750 (1/2) 800 (1/2)
36 * clks 250 (1/6) 200 (1/8)
37 * clks1 125 (1/12) 100 (1/16)
38 * clks3 187.5 (1/8) 200 (1/8)
39 * clks4 93.7 (1/16) 100 (1/16)
40 * clkp 62.5 (1/24) 50 (1/32)
41 * clkg 62.5 (1/24) 66.6 (1/24)
42 * clkb, CLKOUT
43 * (MD2 = 0) 62.5 (1/24) 66.6 (1/24)
44 * (MD2 = 1) 41.6 (1/36) 50 (1/32)
45 */
46
47 #define CPG_CLK_CONFIG_INDEX(md) (((md) & (BIT(2)|BIT(1))) >> 1)
48
49 struct cpg_clk_config {
50 unsigned int z_mult;
51 unsigned int z_div;
52 unsigned int zs_and_s_div;
53 unsigned int s1_div;
54 unsigned int p_div;
55 unsigned int b_and_out_div;
56 };
57
58 static const struct cpg_clk_config cpg_clk_configs[4] __initconst = {
59 { 1, 2, 8, 16, 32, 24 },
60 { 2, 3, 6, 12, 24, 24 },
61 { 1, 2, 8, 16, 32, 32 },
62 { 2, 3, 6, 12, 24, 36 },
63 };
64
65 /*
66 * MD PLLA Ratio
67 * 12 11
68 *------------------------
69 * 0 0 x42
70 * 0 1 x48
71 * 1 0 x56
72 * 1 1 x64
73 */
74
75 #define CPG_PLLA_MULT_INDEX(md) (((md) & (BIT(12)|BIT(11))) >> 11)
76
77 static const unsigned int cpg_plla_mult[4] __initconst = { 42, 48, 56, 64 };
78
79 /* -----------------------------------------------------------------------------
80 * Initialization
81 */
82
83 static struct clk * __init
r8a7779_cpg_register_clock(struct device_node * np,const struct cpg_clk_config * config,unsigned int plla_mult,const char * name)84 r8a7779_cpg_register_clock(struct device_node *np,
85 const struct cpg_clk_config *config,
86 unsigned int plla_mult, const char *name)
87 {
88 const char *parent_name = "plla";
89 unsigned int mult = 1;
90 unsigned int div = 1;
91
92 if (!strcmp(name, "plla")) {
93 parent_name = of_clk_get_parent_name(np, 0);
94 mult = plla_mult;
95 } else if (!strcmp(name, "z")) {
96 div = config->z_div;
97 mult = config->z_mult;
98 } else if (!strcmp(name, "zs") || !strcmp(name, "s")) {
99 div = config->zs_and_s_div;
100 } else if (!strcmp(name, "s1")) {
101 div = config->s1_div;
102 } else if (!strcmp(name, "p")) {
103 div = config->p_div;
104 } else if (!strcmp(name, "b") || !strcmp(name, "out")) {
105 div = config->b_and_out_div;
106 } else {
107 return ERR_PTR(-EINVAL);
108 }
109
110 return clk_register_fixed_factor(NULL, name, parent_name, 0, mult, div);
111 }
112
r8a7779_cpg_clocks_init(struct device_node * np)113 static void __init r8a7779_cpg_clocks_init(struct device_node *np)
114 {
115 const struct cpg_clk_config *config;
116 struct clk_onecell_data *data;
117 struct clk **clks;
118 unsigned int i, plla_mult;
119 int num_clks;
120 u32 mode;
121
122 if (rcar_rst_read_mode_pins(&mode))
123 return;
124
125 num_clks = of_property_count_strings(np, "clock-output-names");
126 if (num_clks < 0) {
127 pr_err("%s: failed to count clocks\n", __func__);
128 return;
129 }
130
131 data = kzalloc(sizeof(*data), GFP_KERNEL);
132 clks = kcalloc(CPG_NUM_CLOCKS, sizeof(*clks), GFP_KERNEL);
133 if (data == NULL || clks == NULL) {
134 /* We're leaking memory on purpose, there's no point in cleaning
135 * up as the system won't boot anyway.
136 */
137 return;
138 }
139
140 data->clks = clks;
141 data->clk_num = num_clks;
142
143 config = &cpg_clk_configs[CPG_CLK_CONFIG_INDEX(mode)];
144 plla_mult = cpg_plla_mult[CPG_PLLA_MULT_INDEX(mode)];
145
146 for (i = 0; i < num_clks; ++i) {
147 const char *name;
148 struct clk *clk;
149
150 of_property_read_string_index(np, "clock-output-names", i,
151 &name);
152
153 clk = r8a7779_cpg_register_clock(np, config, plla_mult, name);
154 if (IS_ERR(clk))
155 pr_err("%s: failed to register %pOFn %s clock (%ld)\n",
156 __func__, np, name, PTR_ERR(clk));
157 else
158 data->clks[i] = clk;
159 }
160
161 of_clk_add_provider(np, of_clk_src_onecell_get, data);
162
163 cpg_mstp_add_clk_domain(np);
164 }
165 CLK_OF_DECLARE(r8a7779_cpg_clks, "renesas,r8a7779-cpg-clocks",
166 r8a7779_cpg_clocks_init);
167