xref: /openbmc/linux/drivers/clk/sunxi/clk-a10-pll2.c (revision ae213c44)
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/io.h>
21 #include <linux/of.h>
22 #include <linux/of_address.h>
23 #include <linux/slab.h>
24 
25 #include <dt-bindings/clock/sun4i-a10-pll2.h>
26 
27 #define SUN4I_PLL2_ENABLE		31
28 
29 #define SUN4I_PLL2_PRE_DIV_SHIFT	0
30 #define SUN4I_PLL2_PRE_DIV_WIDTH	5
31 #define SUN4I_PLL2_PRE_DIV_MASK		GENMASK(SUN4I_PLL2_PRE_DIV_WIDTH - 1, 0)
32 
33 #define SUN4I_PLL2_N_SHIFT		8
34 #define SUN4I_PLL2_N_WIDTH		7
35 #define SUN4I_PLL2_N_MASK		GENMASK(SUN4I_PLL2_N_WIDTH - 1, 0)
36 
37 #define SUN4I_PLL2_POST_DIV_SHIFT	26
38 #define SUN4I_PLL2_POST_DIV_WIDTH	4
39 #define SUN4I_PLL2_POST_DIV_MASK	GENMASK(SUN4I_PLL2_POST_DIV_WIDTH - 1, 0)
40 
41 #define SUN4I_PLL2_POST_DIV_VALUE	4
42 
43 #define SUN4I_PLL2_OUTPUTS		4
44 
45 static DEFINE_SPINLOCK(sun4i_a10_pll2_lock);
46 
47 static void __init sun4i_pll2_setup(struct device_node *node,
48 				    int post_div_offset)
49 {
50 	const char *clk_name = node->name, *parent;
51 	struct clk **clks, *base_clk, *prediv_clk;
52 	struct clk_onecell_data *clk_data;
53 	struct clk_multiplier *mult;
54 	struct clk_gate *gate;
55 	void __iomem *reg;
56 	u32 val;
57 
58 	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
59 	if (IS_ERR(reg))
60 		return;
61 
62 	clk_data = kzalloc(sizeof(*clk_data), GFP_KERNEL);
63 	if (!clk_data)
64 		goto err_unmap;
65 
66 	clks = kcalloc(SUN4I_PLL2_OUTPUTS, sizeof(struct clk *), GFP_KERNEL);
67 	if (!clks)
68 		goto err_free_data;
69 
70 	parent = of_clk_get_parent_name(node, 0);
71 	prediv_clk = clk_register_divider(NULL, "pll2-prediv",
72 					  parent, 0, reg,
73 					  SUN4I_PLL2_PRE_DIV_SHIFT,
74 					  SUN4I_PLL2_PRE_DIV_WIDTH,
75 					  CLK_DIVIDER_ONE_BASED | CLK_DIVIDER_ALLOW_ZERO,
76 					  &sun4i_a10_pll2_lock);
77 	if (IS_ERR(prediv_clk)) {
78 		pr_err("Couldn't register the prediv clock\n");
79 		goto err_free_array;
80 	}
81 
82 	/* Setup the gate part of the PLL2 */
83 	gate = kzalloc(sizeof(struct clk_gate), GFP_KERNEL);
84 	if (!gate)
85 		goto err_unregister_prediv;
86 
87 	gate->reg = reg;
88 	gate->bit_idx = SUN4I_PLL2_ENABLE;
89 	gate->lock = &sun4i_a10_pll2_lock;
90 
91 	/* Setup the multiplier part of the PLL2 */
92 	mult = kzalloc(sizeof(struct clk_multiplier), GFP_KERNEL);
93 	if (!mult)
94 		goto err_free_gate;
95 
96 	mult->reg = reg;
97 	mult->shift = SUN4I_PLL2_N_SHIFT;
98 	mult->width = 7;
99 	mult->flags = CLK_MULTIPLIER_ZERO_BYPASS |
100 			CLK_MULTIPLIER_ROUND_CLOSEST;
101 	mult->lock = &sun4i_a10_pll2_lock;
102 
103 	parent = __clk_get_name(prediv_clk);
104 	base_clk = clk_register_composite(NULL, "pll2-base",
105 					  &parent, 1,
106 					  NULL, NULL,
107 					  &mult->hw, &clk_multiplier_ops,
108 					  &gate->hw, &clk_gate_ops,
109 					  CLK_SET_RATE_PARENT);
110 	if (IS_ERR(base_clk)) {
111 		pr_err("Couldn't register the base multiplier clock\n");
112 		goto err_free_multiplier;
113 	}
114 
115 	parent = __clk_get_name(base_clk);
116 
117 	/*
118 	 * PLL2-1x
119 	 *
120 	 * This is supposed to have a post divider, but we won't need
121 	 * to use it, we just need to initialise it to 4, and use a
122 	 * fixed divider.
123 	 */
124 	val = readl(reg);
125 	val &= ~(SUN4I_PLL2_POST_DIV_MASK << SUN4I_PLL2_POST_DIV_SHIFT);
126 	val |= (SUN4I_PLL2_POST_DIV_VALUE - post_div_offset) << SUN4I_PLL2_POST_DIV_SHIFT;
127 	writel(val, reg);
128 
129 	of_property_read_string_index(node, "clock-output-names",
130 				      SUN4I_A10_PLL2_1X, &clk_name);
131 	clks[SUN4I_A10_PLL2_1X] = clk_register_fixed_factor(NULL, clk_name,
132 							    parent,
133 							    CLK_SET_RATE_PARENT,
134 							    1,
135 							    SUN4I_PLL2_POST_DIV_VALUE);
136 	WARN_ON(IS_ERR(clks[SUN4I_A10_PLL2_1X]));
137 
138 	/*
139 	 * PLL2-2x
140 	 *
141 	 * This clock doesn't use the post divider, and really is just
142 	 * a fixed divider from the PLL2 base clock.
143 	 */
144 	of_property_read_string_index(node, "clock-output-names",
145 				      SUN4I_A10_PLL2_2X, &clk_name);
146 	clks[SUN4I_A10_PLL2_2X] = clk_register_fixed_factor(NULL, clk_name,
147 							    parent,
148 							    CLK_SET_RATE_PARENT,
149 							    1, 2);
150 	WARN_ON(IS_ERR(clks[SUN4I_A10_PLL2_2X]));
151 
152 	/* PLL2-4x */
153 	of_property_read_string_index(node, "clock-output-names",
154 				      SUN4I_A10_PLL2_4X, &clk_name);
155 	clks[SUN4I_A10_PLL2_4X] = clk_register_fixed_factor(NULL, clk_name,
156 							    parent,
157 							    CLK_SET_RATE_PARENT,
158 							    1, 1);
159 	WARN_ON(IS_ERR(clks[SUN4I_A10_PLL2_4X]));
160 
161 	/* PLL2-8x */
162 	of_property_read_string_index(node, "clock-output-names",
163 				      SUN4I_A10_PLL2_8X, &clk_name);
164 	clks[SUN4I_A10_PLL2_8X] = clk_register_fixed_factor(NULL, clk_name,
165 							    parent,
166 							    CLK_SET_RATE_PARENT,
167 							    2, 1);
168 	WARN_ON(IS_ERR(clks[SUN4I_A10_PLL2_8X]));
169 
170 	clk_data->clks = clks;
171 	clk_data->clk_num = SUN4I_PLL2_OUTPUTS;
172 	of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
173 
174 	return;
175 
176 err_free_multiplier:
177 	kfree(mult);
178 err_free_gate:
179 	kfree(gate);
180 err_unregister_prediv:
181 	clk_unregister_divider(prediv_clk);
182 err_free_array:
183 	kfree(clks);
184 err_free_data:
185 	kfree(clk_data);
186 err_unmap:
187 	iounmap(reg);
188 }
189 
190 static void __init sun4i_a10_pll2_setup(struct device_node *node)
191 {
192 	sun4i_pll2_setup(node, 0);
193 }
194 
195 CLK_OF_DECLARE(sun4i_a10_pll2, "allwinner,sun4i-a10-pll2-clk",
196 	       sun4i_a10_pll2_setup);
197 
198 static void __init sun5i_a13_pll2_setup(struct device_node *node)
199 {
200 	sun4i_pll2_setup(node, 1);
201 }
202 
203 CLK_OF_DECLARE(sun5i_a13_pll2, "allwinner,sun5i-a13-pll2-clk",
204 	       sun5i_a13_pll2_setup);
205