aboutsummaryrefslogtreecommitdiff
path: root/arch/arm/mach-omap2/dpll44xx.c
blob: 09d0ccccb86196650f2ff220b1134320f7c3fb8a (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
/*
 * OMAP4-specific DPLL control functions
 *
 * Copyright (C) 2011 Texas Instruments, Inc.
 * Rajendra Nayak
 *
 * 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.
 */

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

#include <plat/clock.h>

#include "soc.h"
#include "clock.h"
#include "clock44xx.h"
#include "cm-regbits-44xx.h"

/* Supported only on OMAP4 */
int omap4_dpllmx_gatectrl_read(struct clk *clk)
{
	u32 v;
	u32 mask;

	if (!clk || !clk->clksel_reg || !cpu_is_omap44xx())
		return -EINVAL;

	mask = clk->flags & CLOCK_CLKOUTX2 ?
			OMAP4430_DPLL_CLKOUTX2_GATE_CTRL_MASK :
			OMAP4430_DPLL_CLKOUT_GATE_CTRL_MASK;

	v = __raw_readl(clk->clksel_reg);
	v &= mask;
	v >>= __ffs(mask);

	return v;
}

void omap4_dpllmx_allow_gatectrl(struct clk *clk)
{
	u32 v;
	u32 mask;

	if (!clk || !clk->clksel_reg || !cpu_is_omap44xx())
		return;

	mask = clk->flags & CLOCK_CLKOUTX2 ?
			OMAP4430_DPLL_CLKOUTX2_GATE_CTRL_MASK :
			OMAP4430_DPLL_CLKOUT_GATE_CTRL_MASK;

	v = __raw_readl(clk->clksel_reg);
	/* Clear the bit to allow gatectrl */
	v &= ~mask;
	__raw_writel(v, clk->clksel_reg);
}

void omap4_dpllmx_deny_gatectrl(struct clk *clk)
{
	u32 v;
	u32 mask;

	if (!clk || !clk->clksel_reg || !cpu_is_omap44xx())
		return;

	mask = clk->flags & CLOCK_CLKOUTX2 ?
			OMAP4430_DPLL_CLKOUTX2_GATE_CTRL_MASK :
			OMAP4430_DPLL_CLKOUT_GATE_CTRL_MASK;

	v = __raw_readl(clk->clksel_reg);
	/* Set the bit to deny gatectrl */
	v |= mask;
	__raw_writel(v, clk->clksel_reg);
}

const struct clkops clkops_omap4_dpllmx_ops = {
	.allow_idle	= omap4_dpllmx_allow_gatectrl,
	.deny_idle	= omap4_dpllmx_deny_gatectrl,
};

/**
 * omap4_dpll_regm4xen_recalc - compute DPLL rate, considering REGM4XEN bit
 * @clk: struct clk * of the DPLL to compute the rate for
 *
 * Compute the output rate for the OMAP4 DPLL represented by @clk.
 * Takes the REGM4XEN bit into consideration, which is needed for the
 * OMAP4 ABE DPLL.  Returns the DPLL's output rate (before M-dividers)
 * upon success, or 0 upon error.
 */
unsigned long omap4_dpll_regm4xen_recalc(struct clk *clk)
{
	u32 v;
	unsigned long rate;
	struct dpll_data *dd;

	if (!clk || !clk->dpll_data)
		return 0;

	dd = clk->dpll_data;

	rate = omap2_get_dpll_rate(clk);

	/* regm4xen adds a multiplier of 4 to DPLL calculations */
	v = __raw_readl(dd->control_reg);
	if (v & OMAP4430_DPLL_REGM4XEN_MASK)
		rate *= OMAP4430_REGM4XEN_MULT;

	return rate;
}

/**
 * omap4_dpll_regm4xen_round_rate - round DPLL rate, considering REGM4XEN bit
 * @clk: struct clk * of the DPLL to round a rate for
 * @target_rate: the desired rate of the DPLL
 *
 * Compute the rate that would be programmed into the DPLL hardware
 * for @clk if set_rate() were to be provided with the rate
 * @target_rate.  Takes the REGM4XEN bit into consideration, which is
 * needed for the OMAP4 ABE DPLL.  Returns the rounded rate (before
 * M-dividers) upon success, -EINVAL if @clk is null or not a DPLL, or
 * ~0 if an error occurred in omap2_dpll_round_rate().
 */
long omap4_dpll_regm4xen_round_rate(struct clk *clk, unsigned long target_rate)
{
	u32 v;
	struct dpll_data *dd;
	long r;

	if (!clk || !clk->dpll_data)
		return -EINVAL;

	dd = clk->dpll_data;

	/* regm4xen adds a multiplier of 4 to DPLL calculations */
	v = __raw_readl(dd->control_reg) & OMAP4430_DPLL_REGM4XEN_MASK;

	if (v)
		target_rate = target_rate / OMAP4430_REGM4XEN_MULT;

	r = omap2_dpll_round_rate(clk, target_rate);
	if (r == ~0)
		return r;

	if (v)
		clk->dpll_data->last_rounded_rate *= OMAP4430_REGM4XEN_MULT;

	return clk->dpll_data->last_rounded_rate;
}