1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2014 Samsung Electronics Co., Ltd.
4 * Author: Tomasz Figa <t.figa@samsung.com>
5 *
6 * Clock driver for Exynos clock output
7 */
8
9 #include <linux/slab.h>
10 #include <linux/clk.h>
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/syscore_ops.h>
16
17 #define EXYNOS_CLKOUT_NR_CLKS 1
18 #define EXYNOS_CLKOUT_PARENTS 32
19
20 #define EXYNOS_PMU_DEBUG_REG 0xa00
21 #define EXYNOS_CLKOUT_DISABLE_SHIFT 0
22 #define EXYNOS_CLKOUT_MUX_SHIFT 8
23 #define EXYNOS4_CLKOUT_MUX_MASK 0xf
24 #define EXYNOS5_CLKOUT_MUX_MASK 0x1f
25
26 struct exynos_clkout {
27 struct clk_gate gate;
28 struct clk_mux mux;
29 spinlock_t slock;
30 void __iomem *reg;
31 u32 pmu_debug_save;
32 struct clk_hw_onecell_data data;
33 };
34
35 static struct exynos_clkout *clkout;
36
exynos_clkout_suspend(void)37 static int exynos_clkout_suspend(void)
38 {
39 clkout->pmu_debug_save = readl(clkout->reg + EXYNOS_PMU_DEBUG_REG);
40
41 return 0;
42 }
43
exynos_clkout_resume(void)44 static void exynos_clkout_resume(void)
45 {
46 writel(clkout->pmu_debug_save, clkout->reg + EXYNOS_PMU_DEBUG_REG);
47 }
48
49 static struct syscore_ops exynos_clkout_syscore_ops = {
50 .suspend = exynos_clkout_suspend,
51 .resume = exynos_clkout_resume,
52 };
53
exynos_clkout_init(struct device_node * node,u32 mux_mask)54 static void __init exynos_clkout_init(struct device_node *node, u32 mux_mask)
55 {
56 const char *parent_names[EXYNOS_CLKOUT_PARENTS];
57 struct clk *parents[EXYNOS_CLKOUT_PARENTS];
58 int parent_count;
59 int ret;
60 int i;
61
62 clkout = kzalloc(struct_size(clkout, data.hws, EXYNOS_CLKOUT_NR_CLKS),
63 GFP_KERNEL);
64 if (!clkout)
65 return;
66
67 spin_lock_init(&clkout->slock);
68
69 parent_count = 0;
70 for (i = 0; i < EXYNOS_CLKOUT_PARENTS; ++i) {
71 char name[] = "clkoutXX";
72
73 snprintf(name, sizeof(name), "clkout%d", i);
74 parents[i] = of_clk_get_by_name(node, name);
75 if (IS_ERR(parents[i])) {
76 parent_names[i] = "none";
77 continue;
78 }
79
80 parent_names[i] = __clk_get_name(parents[i]);
81 parent_count = i + 1;
82 }
83
84 if (!parent_count)
85 goto free_clkout;
86
87 clkout->reg = of_iomap(node, 0);
88 if (!clkout->reg)
89 goto clks_put;
90
91 clkout->gate.reg = clkout->reg + EXYNOS_PMU_DEBUG_REG;
92 clkout->gate.bit_idx = EXYNOS_CLKOUT_DISABLE_SHIFT;
93 clkout->gate.flags = CLK_GATE_SET_TO_DISABLE;
94 clkout->gate.lock = &clkout->slock;
95
96 clkout->mux.reg = clkout->reg + EXYNOS_PMU_DEBUG_REG;
97 clkout->mux.mask = mux_mask;
98 clkout->mux.shift = EXYNOS_CLKOUT_MUX_SHIFT;
99 clkout->mux.lock = &clkout->slock;
100
101 clkout->data.hws[0] = clk_hw_register_composite(NULL, "clkout",
102 parent_names, parent_count, &clkout->mux.hw,
103 &clk_mux_ops, NULL, NULL, &clkout->gate.hw,
104 &clk_gate_ops, CLK_SET_RATE_PARENT
105 | CLK_SET_RATE_NO_REPARENT);
106 if (IS_ERR(clkout->data.hws[0]))
107 goto err_unmap;
108
109 clkout->data.num = EXYNOS_CLKOUT_NR_CLKS;
110 ret = of_clk_add_hw_provider(node, of_clk_hw_onecell_get, &clkout->data);
111 if (ret)
112 goto err_clk_unreg;
113
114 register_syscore_ops(&exynos_clkout_syscore_ops);
115
116 return;
117
118 err_clk_unreg:
119 clk_hw_unregister(clkout->data.hws[0]);
120 err_unmap:
121 iounmap(clkout->reg);
122 clks_put:
123 for (i = 0; i < EXYNOS_CLKOUT_PARENTS; ++i)
124 if (!IS_ERR(parents[i]))
125 clk_put(parents[i]);
126 free_clkout:
127 kfree(clkout);
128
129 pr_err("%s: failed to register clkout clock\n", __func__);
130 }
131
132 /*
133 * We use CLK_OF_DECLARE_DRIVER initialization method to avoid setting
134 * the OF_POPULATED flag on the pmu device tree node, so later the
135 * Exynos PMU platform device can be properly probed with PMU driver.
136 */
137
exynos4_clkout_init(struct device_node * node)138 static void __init exynos4_clkout_init(struct device_node *node)
139 {
140 exynos_clkout_init(node, EXYNOS4_CLKOUT_MUX_MASK);
141 }
142 CLK_OF_DECLARE_DRIVER(exynos4210_clkout, "samsung,exynos4210-pmu",
143 exynos4_clkout_init);
144 CLK_OF_DECLARE_DRIVER(exynos4412_clkout, "samsung,exynos4412-pmu",
145 exynos4_clkout_init);
146 CLK_OF_DECLARE_DRIVER(exynos3250_clkout, "samsung,exynos3250-pmu",
147 exynos4_clkout_init);
148
exynos5_clkout_init(struct device_node * node)149 static void __init exynos5_clkout_init(struct device_node *node)
150 {
151 exynos_clkout_init(node, EXYNOS5_CLKOUT_MUX_MASK);
152 }
153 CLK_OF_DECLARE_DRIVER(exynos5250_clkout, "samsung,exynos5250-pmu",
154 exynos5_clkout_init);
155 CLK_OF_DECLARE_DRIVER(exynos5410_clkout, "samsung,exynos5410-pmu",
156 exynos5_clkout_init);
157 CLK_OF_DECLARE_DRIVER(exynos5420_clkout, "samsung,exynos5420-pmu",
158 exynos5_clkout_init);
159 CLK_OF_DECLARE_DRIVER(exynos5433_clkout, "samsung,exynos5433-pmu",
160 exynos5_clkout_init);
161
