summaryrefslogtreecommitdiffstats
path: root/drivers/clk/ux500/clk-prcc.c
blob: bd4769a8448582284b2734b0a77cfa6484306e17 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
/*
 * PRCC clock implementation for ux500 platform.
 *
 * Copyright (C) 2012 ST-Ericsson SA
 * Author: Ulf Hansson <ulf.hansson@linaro.org>
 *
 * License terms: GNU General Public License (GPL) version 2
 */

#include <linux/clk-provider.h>
#include <linux/clk-private.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/err.h>
#include <linux/types.h>

#include "clk.h"

#define PRCC_PCKEN			0x000
#define PRCC_PCKDIS			0x004
#define PRCC_KCKEN			0x008
#define PRCC_KCKDIS			0x00C
#define PRCC_PCKSR			0x010
#define PRCC_KCKSR			0x014

#define to_clk_prcc(_hw) container_of(_hw, struct clk_prcc, hw)

struct clk_prcc {
	struct clk_hw hw;
	void __iomem *base;
	u32 cg_sel;
	int is_enabled;
};

/* PRCC clock operations. */

static int clk_prcc_pclk_enable(struct clk_hw *hw)
{
	struct clk_prcc *clk = to_clk_prcc(hw);

	writel(clk->cg_sel, (clk->base + PRCC_PCKEN));
	while (!(readl(clk->base + PRCC_PCKSR) & clk->cg_sel))
		cpu_relax();

	clk->is_enabled = 1;
	return 0;
}

static void clk_prcc_pclk_disable(struct clk_hw *hw)
{
	struct clk_prcc *clk = to_clk_prcc(hw);

	writel(clk->cg_sel, (clk->base + PRCC_PCKDIS));
	clk->is_enabled = 0;
}

static int clk_prcc_kclk_enable(struct clk_hw *hw)
{
	struct clk_prcc *clk = to_clk_prcc(hw);

	writel(clk->cg_sel, (clk->base + PRCC_KCKEN));
	while (!(readl(clk->base + PRCC_KCKSR) & clk->cg_sel))
		cpu_relax();

	clk->is_enabled = 1;
	return 0;
}

static void clk_prcc_kclk_disable(struct clk_hw *hw)
{
	struct clk_prcc *clk = to_clk_prcc(hw);

	writel(clk->cg_sel, (clk->base + PRCC_KCKDIS));
	clk->is_enabled = 0;
}

static int clk_prcc_is_enabled(struct clk_hw *hw)
{
	struct clk_prcc *clk = to_clk_prcc(hw);
	return clk->is_enabled;
}

static struct clk_ops clk_prcc_pclk_ops = {
	.enable = clk_prcc_pclk_enable,
	.disable = clk_prcc_pclk_disable,
	.is_enabled = clk_prcc_is_enabled,
};

static struct clk_ops clk_prcc_kclk_ops = {
	.enable = clk_prcc_kclk_enable,
	.disable = clk_prcc_kclk_disable,
	.is_enabled = clk_prcc_is_enabled,
};

static struct clk *clk_reg_prcc(const char *name,
				const char *parent_name,
				resource_size_t phy_base,
				u32 cg_sel,
				unsigned long flags,
				struct clk_ops *clk_prcc_ops)
{
	struct clk_prcc *clk;
	struct clk_init_data clk_prcc_init;
	struct clk *clk_reg;

	if (!name) {
		pr_err("clk_prcc: %s invalid arguments passed\n", __func__);
		return ERR_PTR(-EINVAL);
	}

	clk = kzalloc(sizeof(struct clk_prcc), GFP_KERNEL);
	if (!clk) {
		pr_err("clk_prcc: %s could not allocate clk\n", __func__);
		return ERR_PTR(-ENOMEM);
	}

	clk->base = ioremap(phy_base, SZ_4K);
	if (!clk->base)
		goto free_clk;

	clk->cg_sel = cg_sel;
	clk->is_enabled = 1;

	clk_prcc_init.name = name;
	clk_prcc_init.ops = clk_prcc_ops;
	clk_prcc_init.flags = flags;
	clk_prcc_init.parent_names = (parent_name ? &parent_name : NULL);
	clk_prcc_init.num_parents = (parent_name ? 1 : 0);
	clk->hw.init = &clk_prcc_init;

	clk_reg = clk_register(NULL, &clk->hw);
	if (IS_ERR_OR_NULL(clk_reg))
		goto unmap_clk;

	return clk_reg;

unmap_clk:
	iounmap(clk->base);
free_clk:
	kfree(clk);
	pr_err("clk_prcc: %s failed to register clk\n", __func__);
	return ERR_PTR(-ENOMEM);
}

struct clk *clk_reg_prcc_pclk(const char *name,
			      const char *parent_name,
			      resource_size_t phy_base,
			      u32 cg_sel,
			      unsigned long flags)
{
	return clk_reg_prcc(name, parent_name, phy_base, cg_sel, flags,
			&clk_prcc_pclk_ops);
}

struct clk *clk_reg_prcc_kclk(const char *name,
			      const char *parent_name,
			      resource_size_t phy_base,
			      u32 cg_sel,
			      unsigned long flags)
{
	return clk_reg_prcc(name, parent_name, phy_base, cg_sel, flags,
			&clk_prcc_kclk_ops);
}
OpenPOWER on IntegriCloud