1 /*
2  * Copyright (C) 2015 Jens Kuske <jenskuske@gmail.com>
3  *
4  * Based on clk-simple-gates.c, which is:
5  * Copyright 2015 Maxime Ripard
6  *
7  * Maxime Ripard <maxime.ripard@free-electrons.com>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  */
19 
20 #include <linux/clk-provider.h>
21 #include <linux/io.h>
22 #include <linux/of.h>
23 #include <linux/of_address.h>
24 #include <linux/slab.h>
25 #include <linux/spinlock.h>
26 
27 static DEFINE_SPINLOCK(gates_lock);
28 
29 static void __init sun8i_h3_bus_gates_init(struct device_node *node)
30 {
31 	static const char * const names[] = { "ahb1", "ahb2", "apb1", "apb2" };
32 	enum { AHB1, AHB2, APB1, APB2, PARENT_MAX } clk_parent;
33 	const char *parents[PARENT_MAX];
34 	struct clk_onecell_data *clk_data;
35 	const char *clk_name;
36 	struct property *prop;
37 	struct resource res;
38 	void __iomem *clk_reg;
39 	void __iomem *reg;
40 	const __be32 *p;
41 	int number, i;
42 	u8 clk_bit;
43 	int index;
44 
45 	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
46 	if (IS_ERR(reg))
47 		return;
48 
49 	for (i = 0; i < ARRAY_SIZE(names); i++) {
50 		int idx = of_property_match_string(node, "clock-names",
51 						   names[i]);
52 		if (idx < 0)
53 			return;
54 
55 		parents[i] = of_clk_get_parent_name(node, idx);
56 	}
57 
58 	clk_data = kmalloc(sizeof(struct clk_onecell_data), GFP_KERNEL);
59 	if (!clk_data)
60 		goto err_unmap;
61 
62 	number = of_property_count_u32_elems(node, "clock-indices");
63 	of_property_read_u32_index(node, "clock-indices", number - 1, &number);
64 
65 	clk_data->clks = kcalloc(number + 1, sizeof(struct clk *), GFP_KERNEL);
66 	if (!clk_data->clks)
67 		goto err_free_data;
68 
69 	i = 0;
70 	of_property_for_each_u32(node, "clock-indices", prop, p, index) {
71 		of_property_read_string_index(node, "clock-output-names",
72 					      i, &clk_name);
73 
74 		if (index == 17 || (index >= 29 && index <= 31))
75 			clk_parent = AHB2;
76 		else if (index <= 63 || index >= 128)
77 			clk_parent = AHB1;
78 		else if (index >= 64 && index <= 95)
79 			clk_parent = APB1;
80 		else if (index >= 96 && index <= 127)
81 			clk_parent = APB2;
82 		else {
83 			WARN_ON(true);
84 			continue;
85 		}
86 
87 		clk_reg = reg + 4 * (index / 32);
88 		clk_bit = index % 32;
89 
90 		clk_data->clks[index] = clk_register_gate(NULL, clk_name,
91 							  parents[clk_parent],
92 							  0, clk_reg, clk_bit,
93 							  0, &gates_lock);
94 		i++;
95 
96 		if (IS_ERR(clk_data->clks[index])) {
97 			WARN_ON(true);
98 			continue;
99 		}
100 	}
101 
102 	clk_data->clk_num = number + 1;
103 	of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
104 
105 	return;
106 
107 err_free_data:
108 	kfree(clk_data);
109 err_unmap:
110 	iounmap(reg);
111 	of_address_to_resource(node, 0, &res);
112 	release_mem_region(res.start, resource_size(&res));
113 }
114 
115 CLK_OF_DECLARE(sun8i_h3_bus_gates, "allwinner,sun8i-h3-bus-gates-clk",
116 	       sun8i_h3_bus_gates_init);
117 CLK_OF_DECLARE(sun8i_a83t_bus_gates, "allwinner,sun8i-a83t-bus-gates-clk",
118 	       sun8i_h3_bus_gates_init);
119