1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright 2015 Chen-Yu Tsai
4 *
5 * Chen-Yu Tsai <wens@csie.org>
6 */
7
8 #include <linux/clk-provider.h>
9 #include <linux/io.h>
10 #include <linux/of.h>
11 #include <linux/of_address.h>
12 #include <linux/reset-controller.h>
13 #include <linux/slab.h>
14 #include <linux/spinlock.h>
15
16 static DEFINE_SPINLOCK(ve_lock);
17
18 #define SUN4I_VE_ENABLE 31
19 #define SUN4I_VE_DIVIDER_SHIFT 16
20 #define SUN4I_VE_DIVIDER_WIDTH 3
21 #define SUN4I_VE_RESET 0
22
23 /**
24 * sunxi_ve_reset... - reset bit in ve clk registers handling
25 */
26
27 struct ve_reset_data {
28 void __iomem *reg;
29 spinlock_t *lock;
30 struct reset_controller_dev rcdev;
31 };
32
sunxi_ve_reset_assert(struct reset_controller_dev * rcdev,unsigned long id)33 static int sunxi_ve_reset_assert(struct reset_controller_dev *rcdev,
34 unsigned long id)
35 {
36 struct ve_reset_data *data = container_of(rcdev,
37 struct ve_reset_data,
38 rcdev);
39 unsigned long flags;
40 u32 reg;
41
42 spin_lock_irqsave(data->lock, flags);
43
44 reg = readl(data->reg);
45 writel(reg & ~BIT(SUN4I_VE_RESET), data->reg);
46
47 spin_unlock_irqrestore(data->lock, flags);
48
49 return 0;
50 }
51
sunxi_ve_reset_deassert(struct reset_controller_dev * rcdev,unsigned long id)52 static int sunxi_ve_reset_deassert(struct reset_controller_dev *rcdev,
53 unsigned long id)
54 {
55 struct ve_reset_data *data = container_of(rcdev,
56 struct ve_reset_data,
57 rcdev);
58 unsigned long flags;
59 u32 reg;
60
61 spin_lock_irqsave(data->lock, flags);
62
63 reg = readl(data->reg);
64 writel(reg | BIT(SUN4I_VE_RESET), data->reg);
65
66 spin_unlock_irqrestore(data->lock, flags);
67
68 return 0;
69 }
70
sunxi_ve_of_xlate(struct reset_controller_dev * rcdev,const struct of_phandle_args * reset_spec)71 static int sunxi_ve_of_xlate(struct reset_controller_dev *rcdev,
72 const struct of_phandle_args *reset_spec)
73 {
74 if (WARN_ON(reset_spec->args_count != 0))
75 return -EINVAL;
76
77 return 0;
78 }
79
80 static const struct reset_control_ops sunxi_ve_reset_ops = {
81 .assert = sunxi_ve_reset_assert,
82 .deassert = sunxi_ve_reset_deassert,
83 };
84
sun4i_ve_clk_setup(struct device_node * node)85 static void __init sun4i_ve_clk_setup(struct device_node *node)
86 {
87 struct clk *clk;
88 struct clk_divider *div;
89 struct clk_gate *gate;
90 struct ve_reset_data *reset_data;
91 const char *parent;
92 const char *clk_name = node->name;
93 void __iomem *reg;
94 int err;
95
96 reg = of_io_request_and_map(node, 0, of_node_full_name(node));
97 if (IS_ERR(reg))
98 return;
99
100 div = kzalloc(sizeof(*div), GFP_KERNEL);
101 if (!div)
102 goto err_unmap;
103
104 gate = kzalloc(sizeof(*gate), GFP_KERNEL);
105 if (!gate)
106 goto err_free_div;
107
108 of_property_read_string(node, "clock-output-names", &clk_name);
109 parent = of_clk_get_parent_name(node, 0);
110
111 gate->reg = reg;
112 gate->bit_idx = SUN4I_VE_ENABLE;
113 gate->lock = &ve_lock;
114
115 div->reg = reg;
116 div->shift = SUN4I_VE_DIVIDER_SHIFT;
117 div->width = SUN4I_VE_DIVIDER_WIDTH;
118 div->lock = &ve_lock;
119
120 clk = clk_register_composite(NULL, clk_name, &parent, 1,
121 NULL, NULL,
122 &div->hw, &clk_divider_ops,
123 &gate->hw, &clk_gate_ops,
124 CLK_SET_RATE_PARENT);
125 if (IS_ERR(clk))
126 goto err_free_gate;
127
128 err = of_clk_add_provider(node, of_clk_src_simple_get, clk);
129 if (err)
130 goto err_unregister_clk;
131
132 reset_data = kzalloc(sizeof(*reset_data), GFP_KERNEL);
133 if (!reset_data)
134 goto err_del_provider;
135
136 reset_data->reg = reg;
137 reset_data->lock = &ve_lock;
138 reset_data->rcdev.nr_resets = 1;
139 reset_data->rcdev.ops = &sunxi_ve_reset_ops;
140 reset_data->rcdev.of_node = node;
141 reset_data->rcdev.of_xlate = sunxi_ve_of_xlate;
142 reset_data->rcdev.of_reset_n_cells = 0;
143 err = reset_controller_register(&reset_data->rcdev);
144 if (err)
145 goto err_free_reset;
146
147 return;
148
149 err_free_reset:
150 kfree(reset_data);
151 err_del_provider:
152 of_clk_del_provider(node);
153 err_unregister_clk:
154 clk_unregister(clk);
155 err_free_gate:
156 kfree(gate);
157 err_free_div:
158 kfree(div);
159 err_unmap:
160 iounmap(reg);
161 }
162 CLK_OF_DECLARE(sun4i_ve, "allwinner,sun4i-a10-ve-clk",
163 sun4i_ve_clk_setup);
164