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
26struct 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
35static struct exynos_clkout *clkout;
36
37static int exynos_clkout_suspend(void)
38{
39	clkout->pmu_debug_save = readl(clkout->reg + EXYNOS_PMU_DEBUG_REG);
40
41	return 0;
42}
43
44static void exynos_clkout_resume(void)
45{
46	writel(clkout->pmu_debug_save, clkout->reg + EXYNOS_PMU_DEBUG_REG);
47}
48
49static struct syscore_ops exynos_clkout_syscore_ops = {
50	.suspend = exynos_clkout_suspend,
51	.resume = exynos_clkout_resume,
52};
53
54static 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
118err_clk_unreg:
119	clk_hw_unregister(clkout->data.hws[0]);
120err_unmap:
121	iounmap(clkout->reg);
122clks_put:
123	for (i = 0; i < EXYNOS_CLKOUT_PARENTS; ++i)
124		if (!IS_ERR(parents[i]))
125			clk_put(parents[i]);
126free_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
138static void __init exynos4_clkout_init(struct device_node *node)
139{
140	exynos_clkout_init(node, EXYNOS4_CLKOUT_MUX_MASK);
141}
142CLK_OF_DECLARE_DRIVER(exynos4210_clkout, "samsung,exynos4210-pmu",
143		exynos4_clkout_init);
144CLK_OF_DECLARE_DRIVER(exynos4412_clkout, "samsung,exynos4412-pmu",
145		exynos4_clkout_init);
146CLK_OF_DECLARE_DRIVER(exynos3250_clkout, "samsung,exynos3250-pmu",
147		exynos4_clkout_init);
148
149static void __init exynos5_clkout_init(struct device_node *node)
150{
151	exynos_clkout_init(node, EXYNOS5_CLKOUT_MUX_MASK);
152}
153CLK_OF_DECLARE_DRIVER(exynos5250_clkout, "samsung,exynos5250-pmu",
154		exynos5_clkout_init);
155CLK_OF_DECLARE_DRIVER(exynos5410_clkout, "samsung,exynos5410-pmu",
156		exynos5_clkout_init);
157CLK_OF_DECLARE_DRIVER(exynos5420_clkout, "samsung,exynos5420-pmu",
158		exynos5_clkout_init);
159CLK_OF_DECLARE_DRIVER(exynos5433_clkout, "samsung,exynos5433-pmu",
160		exynos5_clkout_init);
161