xref: /openbmc/linux/drivers/clk/sunxi/clk-a10-pll2.c (revision 460d0d44)
1 /*
2  * Copyright 2013 Emilio López
3  * Emilio López <emilio@elopez.com.ar>
4  *
5  * Copyright 2015 Maxime Ripard
6  * Maxime Ripard <maxime.ripard@free-electrons.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  */
18 
19 #include <linux/clk-provider.h>
20 #include <linux/of.h>
21 #include <linux/of_address.h>
22 #include <linux/slab.h>
23 
24 #include <dt-bindings/clock/sun4i-a10-pll2.h>
25 
26 #define SUN4I_PLL2_ENABLE		31
27 
28 #define SUN4I_PLL2_PRE_DIV_SHIFT	0
29 #define SUN4I_PLL2_PRE_DIV_WIDTH	5
30 #define SUN4I_PLL2_PRE_DIV_MASK		GENMASK(SUN4I_PLL2_PRE_DIV_WIDTH - 1, 0)
31 
32 #define SUN4I_PLL2_N_SHIFT		8
33 #define SUN4I_PLL2_N_WIDTH		7
34 #define SUN4I_PLL2_N_MASK		GENMASK(SUN4I_PLL2_N_WIDTH - 1, 0)
35 
36 #define SUN4I_PLL2_POST_DIV_SHIFT	26
37 #define SUN4I_PLL2_POST_DIV_WIDTH	4
38 #define SUN4I_PLL2_POST_DIV_MASK	GENMASK(SUN4I_PLL2_POST_DIV_WIDTH - 1, 0)
39 
40 #define SUN4I_PLL2_POST_DIV_VALUE	4
41 
42 #define SUN4I_PLL2_OUTPUTS		4
43 
44 static DEFINE_SPINLOCK(sun4i_a10_pll2_lock);
45 
46 static void __init sun4i_pll2_setup(struct device_node *node)
47 {
48 	const char *clk_name = node->name, *parent;
49 	struct clk **clks, *base_clk, *prediv_clk;
50 	struct clk_onecell_data *clk_data;
51 	struct clk_multiplier *mult;
52 	struct clk_gate *gate;
53 	void __iomem *reg;
54 	u32 val;
55 
56 	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
57 	if (IS_ERR(reg))
58 		return;
59 
60 	clk_data = kzalloc(sizeof(*clk_data), GFP_KERNEL);
61 	if (!clk_data)
62 		goto err_unmap;
63 
64 	clks = kcalloc(SUN4I_PLL2_OUTPUTS, sizeof(struct clk *), GFP_KERNEL);
65 	if (!clks)
66 		goto err_free_data;
67 
68 	parent = of_clk_get_parent_name(node, 0);
69 	prediv_clk = clk_register_divider(NULL, "pll2-prediv",
70 					  parent, 0, reg,
71 					  SUN4I_PLL2_PRE_DIV_SHIFT,
72 					  SUN4I_PLL2_PRE_DIV_WIDTH,
73 					  CLK_DIVIDER_ONE_BASED |
74 					  CLK_DIVIDER_ALLOW_ZERO,
75 					  &sun4i_a10_pll2_lock);
76 	if (!prediv_clk) {
77 		pr_err("Couldn't register the prediv clock\n");
78 		goto err_free_array;
79 	}
80 
81 	/* Setup the gate part of the PLL2 */
82 	gate = kzalloc(sizeof(struct clk_gate), GFP_KERNEL);
83 	if (!gate)
84 		goto err_unregister_prediv;
85 
86 	gate->reg = reg;
87 	gate->bit_idx = SUN4I_PLL2_ENABLE;
88 	gate->lock = &sun4i_a10_pll2_lock;
89 
90 	/* Setup the multiplier part of the PLL2 */
91 	mult = kzalloc(sizeof(struct clk_multiplier), GFP_KERNEL);
92 	if (!mult)
93 		goto err_free_gate;
94 
95 	mult->reg = reg;
96 	mult->shift = SUN4I_PLL2_N_SHIFT;
97 	mult->width = 7;
98 	mult->flags = CLK_MULTIPLIER_ZERO_BYPASS |
99 			CLK_MULTIPLIER_ROUND_CLOSEST;
100 	mult->lock = &sun4i_a10_pll2_lock;
101 
102 	parent = __clk_get_name(prediv_clk);
103 	base_clk = clk_register_composite(NULL, "pll2-base",
104 					  &parent, 1,
105 					  NULL, NULL,
106 					  &mult->hw, &clk_multiplier_ops,
107 					  &gate->hw, &clk_gate_ops,
108 					  CLK_SET_RATE_PARENT);
109 	if (!base_clk) {
110 		pr_err("Couldn't register the base multiplier clock\n");
111 		goto err_free_multiplier;
112 	}
113 
114 	parent = __clk_get_name(base_clk);
115 
116 	/*
117 	 * PLL2-1x
118 	 *
119 	 * This is supposed to have a post divider, but we won't need
120 	 * to use it, we just need to initialise it to 4, and use a
121 	 * fixed divider.
122 	 */
123 	val = readl(reg);
124 	val &= ~(SUN4I_PLL2_POST_DIV_MASK << SUN4I_PLL2_POST_DIV_SHIFT);
125 	val |= SUN4I_PLL2_POST_DIV_VALUE << SUN4I_PLL2_POST_DIV_SHIFT;
126 	writel(val, reg);
127 
128 	of_property_read_string_index(node, "clock-output-names",
129 				      SUN4I_A10_PLL2_1X, &clk_name);
130 	clks[SUN4I_A10_PLL2_1X] = clk_register_fixed_factor(NULL, clk_name,
131 							    parent,
132 							    CLK_SET_RATE_PARENT,
133 							    1,
134 							    SUN4I_PLL2_POST_DIV_VALUE);
135 	WARN_ON(IS_ERR(clks[SUN4I_A10_PLL2_1X]));
136 
137 	/*
138 	 * PLL2-2x
139 	 *
140 	 * This clock doesn't use the post divider, and really is just
141 	 * a fixed divider from the PLL2 base clock.
142 	 */
143 	of_property_read_string_index(node, "clock-output-names",
144 				      SUN4I_A10_PLL2_2X, &clk_name);
145 	clks[SUN4I_A10_PLL2_2X] = clk_register_fixed_factor(NULL, clk_name,
146 							    parent,
147 							    CLK_SET_RATE_PARENT,
148 							    1, 2);
149 	WARN_ON(IS_ERR(clks[SUN4I_A10_PLL2_2X]));
150 
151 	/* PLL2-4x */
152 	of_property_read_string_index(node, "clock-output-names",
153 				      SUN4I_A10_PLL2_4X, &clk_name);
154 	clks[SUN4I_A10_PLL2_4X] = clk_register_fixed_factor(NULL, clk_name,
155 							    parent,
156 							    CLK_SET_RATE_PARENT,
157 							    1, 1);
158 	WARN_ON(IS_ERR(clks[SUN4I_A10_PLL2_4X]));
159 
160 	/* PLL2-8x */
161 	of_property_read_string_index(node, "clock-output-names",
162 				      SUN4I_A10_PLL2_8X, &clk_name);
163 	clks[SUN4I_A10_PLL2_8X] = clk_register_fixed_factor(NULL, clk_name,
164 							    parent,
165 							    CLK_SET_RATE_PARENT,
166 							    2, 1);
167 	WARN_ON(IS_ERR(clks[SUN4I_A10_PLL2_8X]));
168 
169 	clk_data->clks = clks;
170 	clk_data->clk_num = SUN4I_PLL2_OUTPUTS;
171 	of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
172 
173 	return;
174 
175 err_free_multiplier:
176 	kfree(mult);
177 err_free_gate:
178 	kfree(gate);
179 err_unregister_prediv:
180 	clk_unregister_divider(prediv_clk);
181 err_free_array:
182 	kfree(clks);
183 err_free_data:
184 	kfree(clk_data);
185 err_unmap:
186 	iounmap(reg);
187 }
188 CLK_OF_DECLARE(sun4i_pll2, "allwinner,sun4i-a10-pll2-clk", sun4i_pll2_setup);
189