summaryrefslogtreecommitdiff
path: root/drivers/clk/sunxi-ng/ccu_mp.c
blob: b583f186a804df669e974f811e6bef91c4aaa877 (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
164
165
166
167
168
169
170
171
172
173
/*
 * Copyright (C) 2016 Maxime Ripard
 * Maxime Ripard <maxime.ripard@free-electrons.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 */

#include <linux/clk-provider.h>

#include "ccu_gate.h"
#include "ccu_mp.h"

static void ccu_mp_find_best(unsigned long parent, unsigned long rate,
			     unsigned int max_m, unsigned int max_p,
			     unsigned int *m, unsigned int *p)
{
	unsigned long best_rate = 0;
	unsigned int best_m = 0, best_p = 0;
	unsigned int _m, _p;

	for (_p = 1; _p <= max_p; _p <<= 1) {
		for (_m = 1; _m <= max_m; _m++) {
			unsigned long tmp_rate = parent / _p / _m;

			if (tmp_rate > rate)
				continue;

			if ((rate - tmp_rate) < (rate - best_rate)) {
				best_rate = tmp_rate;
				best_m = _m;
				best_p = _p;
			}
		}
	}

	*m = best_m;
	*p = best_p;
}

static unsigned long ccu_mp_round_rate(struct ccu_mux_internal *mux,
				       unsigned long parent_rate,
				       unsigned long rate,
				       void *data)
{
	struct ccu_mp *cmp = data;
	unsigned int max_m, max_p;
	unsigned int m, p;

	max_m = cmp->m.max ?: 1 << cmp->m.width;
	max_p = cmp->p.max ?: 1 << ((1 << cmp->p.width) - 1);

	ccu_mp_find_best(parent_rate, rate, max_m, max_p, &m, &p);

	return parent_rate / p / m;
}

static void ccu_mp_disable(struct clk_hw *hw)
{
	struct ccu_mp *cmp = hw_to_ccu_mp(hw);

	return ccu_gate_helper_disable(&cmp->common, cmp->enable);
}

static int ccu_mp_enable(struct clk_hw *hw)
{
	struct ccu_mp *cmp = hw_to_ccu_mp(hw);

	return ccu_gate_helper_enable(&cmp->common, cmp->enable);
}

static int ccu_mp_is_enabled(struct clk_hw *hw)
{
	struct ccu_mp *cmp = hw_to_ccu_mp(hw);

	return ccu_gate_helper_is_enabled(&cmp->common, cmp->enable);
}

static unsigned long ccu_mp_recalc_rate(struct clk_hw *hw,
					unsigned long parent_rate)
{
	struct ccu_mp *cmp = hw_to_ccu_mp(hw);
	unsigned int m, p;
	u32 reg;

	/* Adjust parent_rate according to pre-dividers */
	ccu_mux_helper_adjust_parent_for_prediv(&cmp->common, &cmp->mux,
						-1, &parent_rate);

	reg = readl(cmp->common.base + cmp->common.reg);

	m = reg >> cmp->m.shift;
	m &= (1 << cmp->m.width) - 1;
	m += cmp->m.offset;
	if (!m)
		m++;

	p = reg >> cmp->p.shift;
	p &= (1 << cmp->p.width) - 1;

	return (parent_rate >> p) / m;
}

static int ccu_mp_determine_rate(struct clk_hw *hw,
				 struct clk_rate_request *req)
{
	struct ccu_mp *cmp = hw_to_ccu_mp(hw);

	return ccu_mux_helper_determine_rate(&cmp->common, &cmp->mux,
					     req, ccu_mp_round_rate, cmp);
}

static int ccu_mp_set_rate(struct clk_hw *hw, unsigned long rate,
			   unsigned long parent_rate)
{
	struct ccu_mp *cmp = hw_to_ccu_mp(hw);
	unsigned long flags;
	unsigned int max_m, max_p;
	unsigned int m, p;
	u32 reg;

	/* Adjust parent_rate according to pre-dividers */
	ccu_mux_helper_adjust_parent_for_prediv(&cmp->common, &cmp->mux,
						-1, &parent_rate);

	max_m = cmp->m.max ?: 1 << cmp->m.width;
	max_p = cmp->p.max ?: 1 << ((1 << cmp->p.width) - 1);

	ccu_mp_find_best(parent_rate, rate, max_m, max_p, &m, &p);

	spin_lock_irqsave(cmp->common.lock, flags);

	reg = readl(cmp->common.base + cmp->common.reg);
	reg &= ~GENMASK(cmp->m.width + cmp->m.shift - 1, cmp->m.shift);
	reg &= ~GENMASK(cmp->p.width + cmp->p.shift - 1, cmp->p.shift);
	reg |= (m - cmp->m.offset) << cmp->m.shift;
	reg |= ilog2(p) << cmp->p.shift;

	writel(reg, cmp->common.base + cmp->common.reg);

	spin_unlock_irqrestore(cmp->common.lock, flags);

	return 0;
}

static u8 ccu_mp_get_parent(struct clk_hw *hw)
{
	struct ccu_mp *cmp = hw_to_ccu_mp(hw);

	return ccu_mux_helper_get_parent(&cmp->common, &cmp->mux);
}

static int ccu_mp_set_parent(struct clk_hw *hw, u8 index)
{
	struct ccu_mp *cmp = hw_to_ccu_mp(hw);

	return ccu_mux_helper_set_parent(&cmp->common, &cmp->mux, index);
}

const struct clk_ops ccu_mp_ops = {
	.disable	= ccu_mp_disable,
	.enable		= ccu_mp_enable,
	.is_enabled	= ccu_mp_is_enabled,

	.get_parent	= ccu_mp_get_parent,
	.set_parent	= ccu_mp_set_parent,

	.determine_rate	= ccu_mp_determine_rate,
	.recalc_rate	= ccu_mp_recalc_rate,
	.set_rate	= ccu_mp_set_rate,
};