aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-pxa/clock-pxa3xx.c
blob: 3f864cd0bd2893d786bc0441576a8c648a4435d3 (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
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
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
/*
 * linux/arch/arm/mach-pxa/clock-pxa3xx.c
 *
 * 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/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>

#include <mach/smemc.h>
#include <mach/pxa3xx-regs.h>

#include "clock.h"

/* Crystal clock: 13MHz */
#define BASE_CLK	13000000

/* Ring Oscillator Clock: 60MHz */
#define RO_CLK		60000000

#define ACCR_D0CS	(1 << 26)
#define ACCR_PCCE	(1 << 11)

/* crystal frequency to HSIO bus frequency multiplier (HSS) */
static unsigned char hss_mult[4] = { 8, 12, 16, 24 };

/*
 * Get the clock frequency as reflected by CCSR and the turbo flag.
 * We assume these values have been applied via a fcs.
 * If info is not 0 we also display the current settings.
 */
unsigned int pxa3xx_get_clk_frequency_khz(int info)
{
	unsigned long acsr, xclkcfg;
	unsigned int t, xl, xn, hss, ro, XL, XN, CLK, HSS;

	/* Read XCLKCFG register turbo bit */
	__asm__ __volatile__("mrc\tp14, 0, %0, c6, c0, 0" : "=r"(xclkcfg));
	t = xclkcfg & 0x1;

	acsr = ACSR;

	xl  = acsr & 0x1f;
	xn  = (acsr >> 8) & 0x7;
	hss = (acsr >> 14) & 0x3;

	XL = xl * BASE_CLK;
	XN = xn * XL;

	ro = acsr & ACCR_D0CS;

	CLK = (ro) ? RO_CLK : ((t) ? XN : XL);
	HSS = (ro) ? RO_CLK : hss_mult[hss] * BASE_CLK;

	if (info) {
		pr_info("RO Mode clock: %d.%02dMHz (%sactive)\n",
			RO_CLK / 1000000, (RO_CLK % 1000000) / 10000,
			(ro) ? "" : "in");
		pr_info("Run Mode clock: %d.%02dMHz (*%d)\n",
			XL / 1000000, (XL % 1000000) / 10000, xl);
		pr_info("Turbo Mode clock: %d.%02dMHz (*%d, %sactive)\n",
			XN / 1000000, (XN % 1000000) / 10000, xn,
			(t) ? "" : "in");
		pr_info("HSIO bus clock: %d.%02dMHz\n",
			HSS / 1000000, (HSS % 1000000) / 10000);
	}

	return CLK / 1000;
}

/*
 * Return the current AC97 clock frequency.
 */
static unsigned long clk_pxa3xx_ac97_getrate(struct clk *clk)
{
	unsigned long rate = 312000000;
	unsigned long ac97_div;

	ac97_div = AC97_DIV;

	/* This may loose precision for some rates but won't for the
	 * standard 24.576MHz.
	 */
	rate /= (ac97_div >> 12) & 0x7fff;
	rate *= (ac97_div & 0xfff);

	return rate;
}

/*
 * Return the current HSIO bus clock frequency
 */
static unsigned long clk_pxa3xx_hsio_getrate(struct clk *clk)
{
	unsigned long acsr;
	unsigned int hss, hsio_clk;

	acsr = ACSR;

	hss = (acsr >> 14) & 0x3;
	hsio_clk = (acsr & ACCR_D0CS) ? RO_CLK : hss_mult[hss] * BASE_CLK;

	return hsio_clk;
}

/* crystal frequency to static memory controller multiplier (SMCFS) */
static unsigned int smcfs_mult[8] = { 6, 0, 8, 0, 0, 16, };
static unsigned int df_clkdiv[4] = { 1, 2, 4, 1 };

static unsigned long clk_pxa3xx_smemc_getrate(struct clk *clk)
{
	unsigned long acsr = ACSR;
	unsigned long memclkcfg = __raw_readl(MEMCLKCFG);

	return BASE_CLK * smcfs_mult[(acsr >> 23) & 0x7] /
			df_clkdiv[(memclkcfg >> 16) & 0x3];
}

void clk_pxa3xx_cken_enable(struct clk *clk)
{
	unsigned long mask = 1ul << (clk->cken & 0x1f);

	if (clk->cken < 32)
		CKENA |= mask;
	else
		CKENB |= mask;
}

void clk_pxa3xx_cken_disable(struct clk *clk)
{
	unsigned long mask = 1ul << (clk->cken & 0x1f);

	if (clk->cken < 32)
		CKENA &= ~mask;
	else
		CKENB &= ~mask;
}

const struct clkops clk_pxa3xx_cken_ops = {
	.enable		= clk_pxa3xx_cken_enable,
	.disable	= clk_pxa3xx_cken_disable,
};

const struct clkops clk_pxa3xx_hsio_ops = {
	.enable		= clk_pxa3xx_cken_enable,
	.disable	= clk_pxa3xx_cken_disable,
	.getrate	= clk_pxa3xx_hsio_getrate,
};

const struct clkops clk_pxa3xx_ac97_ops = {
	.enable		= clk_pxa3xx_cken_enable,
	.disable	= clk_pxa3xx_cken_disable,
	.getrate	= clk_pxa3xx_ac97_getrate,
};

const struct clkops clk_pxa3xx_smemc_ops = {
	.enable		= clk_pxa3xx_cken_enable,
	.disable	= clk_pxa3xx_cken_disable,
	.getrate	= clk_pxa3xx_smemc_getrate,
};

static void clk_pout_enable(struct clk *clk)
{
	OSCC |= OSCC_PEN;
}

static void clk_pout_disable(struct clk *clk)
{
	OSCC &= ~OSCC_PEN;
}

const struct clkops clk_pxa3xx_pout_ops = {
	.enable		= clk_pout_enable,
	.disable	= clk_pout_disable,
};

#ifdef CONFIG_PM
static uint32_t cken[2];
static uint32_t accr;

static int pxa3xx_clock_suspend(struct sys_device *d, pm_message_t state)
{
	cken[0] = CKENA;
	cken[1] = CKENB;
	accr = ACCR;
	return 0;
}

static int pxa3xx_clock_resume(struct sys_device *d)
{
	ACCR = accr;
	CKENA = cken[0];
	CKENB = cken[1];
	return 0;
}
#else
#define pxa3xx_clock_suspend	NULL
#define pxa3xx_clock_resume	NULL
#endif

struct sysdev_class pxa3xx_clock_sysclass = {
	.name		= "pxa3xx-clock",
	.suspend	= pxa3xx_clock_suspend,
	.resume		= pxa3xx_clock_resume,
};

static int __init pxa3xx_clock_init(void)
{
	if (cpu_is_pxa3xx() || cpu_is_pxa95x())
		return sysdev_class_register(&pxa3xx_clock_sysclass);
	return 0;
}
postcore_initcall(pxa3xx_clock_init);