aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-omap2/clkt2xxx_apll.c
blob: 25b1feed480d8ae9089d63da213377dfd5d6dc5d (plain) (blame)
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
/*
 * OMAP2xxx APLL clock control functions
 *
 * Copyright (C) 2005-2008 Texas Instruments, Inc.
 * Copyright (C) 2004-2010 Nokia Corporation
 *
 * Contacts:
 * Richard Woodruff <r-woodruff2@ti.com>
 * Paul Walmsley
 *
 * Based on earlier work by Tuukka Tikkanen, Tony Lindgren,
 * Gordon McNutt and RidgeRun, Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#undef DEBUG

#include <linux/kernel.h>
#include <linux/clk.h>
#include <linux/io.h>


#include "clock.h"
#include "clock2xxx.h"
#include "cm2xxx.h"
#include "cm-regbits-24xx.h"

/* CM_CLKEN_PLL.EN_{54,96}M_PLL options (24XX) */
#define EN_APLL_STOPPED			0
#define EN_APLL_LOCKED			3

/* CM_CLKSEL1_PLL.APLLS_CLKIN options (24XX) */
#define APLLS_CLKIN_19_2MHZ		0
#define APLLS_CLKIN_13MHZ		2
#define APLLS_CLKIN_12MHZ		3

/* Private functions */

/**
 * omap2xxx_clk_apll_locked - is the APLL locked?
 * @hw: struct clk_hw * of the APLL to check
 *
 * If the APLL IP block referred to by @hw indicates that it's locked,
 * return true; otherwise, return false.
 */
static bool omap2xxx_clk_apll_locked(struct clk_hw *hw)
{
	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
	u32 r, apll_mask;

	apll_mask = EN_APLL_LOCKED << clk->enable_bit;

	r = omap2_cm_read_mod_reg(PLL_MOD, CM_CLKEN);

	return ((r & apll_mask) == apll_mask) ? true : false;
}

int omap2_clk_apll96_enable(struct clk_hw *hw)
{
	return omap2xxx_cm_apll96_enable();
}

int omap2_clk_apll54_enable(struct clk_hw *hw)
{
	return omap2xxx_cm_apll54_enable();
}

static void _apll96_allow_idle(struct clk_hw_omap *clk)
{
	omap2xxx_cm_set_apll96_auto_low_power_stop();
}

static void _apll96_deny_idle(struct clk_hw_omap *clk)
{
	omap2xxx_cm_set_apll96_disable_autoidle();
}

static void _apll54_allow_idle(struct clk_hw_omap *clk)
{
	omap2xxx_cm_set_apll54_auto_low_power_stop();
}

static void _apll54_deny_idle(struct clk_hw_omap *clk)
{
	omap2xxx_cm_set_apll54_disable_autoidle();
}

void omap2_clk_apll96_disable(struct clk_hw *hw)
{
	omap2xxx_cm_apll96_disable();
}

void omap2_clk_apll54_disable(struct clk_hw *hw)
{
	omap2xxx_cm_apll54_disable();
}

unsigned long omap2_clk_apll54_recalc(struct clk_hw *hw,
				      unsigned long parent_rate)
{
	return (omap2xxx_clk_apll_locked(hw)) ? 54000000 : 0;
}

unsigned long omap2_clk_apll96_recalc(struct clk_hw *hw,
				      unsigned long parent_rate)
{
	return (omap2xxx_clk_apll_locked(hw)) ? 96000000 : 0;
}

/* Public data */
const struct clk_hw_omap_ops clkhwops_apll54 = {
	.allow_idle	= _apll54_allow_idle,
	.deny_idle	= _apll54_deny_idle,
};

const struct clk_hw_omap_ops clkhwops_apll96 = {
	.allow_idle	= _apll96_allow_idle,
	.deny_idle	= _apll96_deny_idle,
};

/* Public functions */

u32 omap2xxx_get_apll_clkin(void)
{
	u32 aplls, srate = 0;

	aplls = omap2_cm_read_mod_reg(PLL_MOD, CM_CLKSEL1);
	aplls &= OMAP24XX_APLLS_CLKIN_MASK;
	aplls >>= OMAP24XX_APLLS_CLKIN_SHIFT;

	if (aplls == APLLS_CLKIN_19_2MHZ)
		srate = 19200000;
	else if (aplls == APLLS_CLKIN_13MHZ)
		srate = 13000000;
	else if (aplls == APLLS_CLKIN_12MHZ)
		srate = 12000000;

	return srate;
}