xref: /linux/drivers/clk/sunxi/clk-sun8i-bus-gates.c (revision 55d0969c451159cff86949b38c39171cab962069)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2015 Jens Kuske <jenskuske@gmail.com>
4  *
5  * Based on clk-simple-gates.c, which is:
6  * Copyright 2015 Maxime Ripard
7  *
8  * Maxime Ripard <maxime.ripard@free-electrons.com>
9  */
10 
11 #include <linux/clk-provider.h>
12 #include <linux/io.h>
13 #include <linux/of.h>
14 #include <linux/of_address.h>
15 #include <linux/slab.h>
16 #include <linux/spinlock.h>
17 
18 static DEFINE_SPINLOCK(gates_lock);
19 
20 static void __init sun8i_h3_bus_gates_init(struct device_node *node)
21 {
22 	static const char * const names[] = { "ahb1", "ahb2", "apb1", "apb2" };
23 	enum { AHB1, AHB2, APB1, APB2, PARENT_MAX } clk_parent;
24 	const char *parents[PARENT_MAX];
25 	struct clk_onecell_data *clk_data;
26 	const char *clk_name;
27 	struct resource res;
28 	void __iomem *clk_reg;
29 	void __iomem *reg;
30 	int number, i;
31 	u8 clk_bit;
32 	int index;
33 
34 	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
35 	if (IS_ERR(reg))
36 		return;
37 
38 	for (i = 0; i < ARRAY_SIZE(names); i++) {
39 		int idx = of_property_match_string(node, "clock-names",
40 						   names[i]);
41 		if (idx < 0)
42 			return;
43 
44 		parents[i] = of_clk_get_parent_name(node, idx);
45 	}
46 
47 	clk_data = kmalloc(sizeof(struct clk_onecell_data), GFP_KERNEL);
48 	if (!clk_data)
49 		goto err_unmap;
50 
51 	number = of_property_count_u32_elems(node, "clock-indices");
52 	of_property_read_u32_index(node, "clock-indices", number - 1, &number);
53 
54 	clk_data->clks = kcalloc(number + 1, sizeof(struct clk *), GFP_KERNEL);
55 	if (!clk_data->clks)
56 		goto err_free_data;
57 
58 	i = 0;
59 	of_property_for_each_u32(node, "clock-indices", index) {
60 		of_property_read_string_index(node, "clock-output-names",
61 					      i, &clk_name);
62 
63 		if (index == 17 || (index >= 29 && index <= 31))
64 			clk_parent = AHB2;
65 		else if (index <= 63 || index >= 128)
66 			clk_parent = AHB1;
67 		else if (index >= 64 && index <= 95)
68 			clk_parent = APB1;
69 		else if (index >= 96 && index <= 127)
70 			clk_parent = APB2;
71 		else {
72 			WARN_ON(true);
73 			continue;
74 		}
75 
76 		clk_reg = reg + 4 * (index / 32);
77 		clk_bit = index % 32;
78 
79 		clk_data->clks[index] = clk_register_gate(NULL, clk_name,
80 							  parents[clk_parent],
81 							  0, clk_reg, clk_bit,
82 							  0, &gates_lock);
83 		i++;
84 
85 		if (IS_ERR(clk_data->clks[index])) {
86 			WARN_ON(true);
87 			continue;
88 		}
89 	}
90 
91 	clk_data->clk_num = number + 1;
92 	of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
93 
94 	return;
95 
96 err_free_data:
97 	kfree(clk_data);
98 err_unmap:
99 	iounmap(reg);
100 	of_address_to_resource(node, 0, &res);
101 	release_mem_region(res.start, resource_size(&res));
102 }
103 
104 CLK_OF_DECLARE(sun8i_h3_bus_gates, "allwinner,sun8i-h3-bus-gates-clk",
105 	       sun8i_h3_bus_gates_init);
106 CLK_OF_DECLARE(sun8i_a83t_bus_gates, "allwinner,sun8i-a83t-bus-gates-clk",
107 	       sun8i_h3_bus_gates_init);
108