1 /*
2  * linux/arch/arm/mach-pxa/clock-pxa3xx.c
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8 
9 #include <linux/module.h>
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/io.h>
13 
14 #include <mach/smemc.h>
15 #include <mach/pxa3xx-regs.h>
16 
17 #include "clock.h"
18 
19 /* Crystal clock: 13MHz */
20 #define BASE_CLK	13000000
21 
22 /* Ring Oscillator Clock: 60MHz */
23 #define RO_CLK		60000000
24 
25 #define ACCR_D0CS	(1 << 26)
26 #define ACCR_PCCE	(1 << 11)
27 
28 /* crystal frequency to HSIO bus frequency multiplier (HSS) */
29 static unsigned char hss_mult[4] = { 8, 12, 16, 24 };
30 
31 /*
32  * Get the clock frequency as reflected by CCSR and the turbo flag.
33  * We assume these values have been applied via a fcs.
34  * If info is not 0 we also display the current settings.
35  */
pxa3xx_get_clk_frequency_khz(int info)36 unsigned int pxa3xx_get_clk_frequency_khz(int info)
37 {
38 	unsigned long acsr, xclkcfg;
39 	unsigned int t, xl, xn, hss, ro, XL, XN, CLK, HSS;
40 
41 	/* Read XCLKCFG register turbo bit */
42 	__asm__ __volatile__("mrc\tp14, 0, %0, c6, c0, 0" : "=r"(xclkcfg));
43 	t = xclkcfg & 0x1;
44 
45 	acsr = ACSR;
46 
47 	xl  = acsr & 0x1f;
48 	xn  = (acsr >> 8) & 0x7;
49 	hss = (acsr >> 14) & 0x3;
50 
51 	XL = xl * BASE_CLK;
52 	XN = xn * XL;
53 
54 	ro = acsr & ACCR_D0CS;
55 
56 	CLK = (ro) ? RO_CLK : ((t) ? XN : XL);
57 	HSS = (ro) ? RO_CLK : hss_mult[hss] * BASE_CLK;
58 
59 	if (info) {
60 		pr_info("RO Mode clock: %d.%02dMHz (%sactive)\n",
61 			RO_CLK / 1000000, (RO_CLK % 1000000) / 10000,
62 			(ro) ? "" : "in");
63 		pr_info("Run Mode clock: %d.%02dMHz (*%d)\n",
64 			XL / 1000000, (XL % 1000000) / 10000, xl);
65 		pr_info("Turbo Mode clock: %d.%02dMHz (*%d, %sactive)\n",
66 			XN / 1000000, (XN % 1000000) / 10000, xn,
67 			(t) ? "" : "in");
68 		pr_info("HSIO bus clock: %d.%02dMHz\n",
69 			HSS / 1000000, (HSS % 1000000) / 10000);
70 	}
71 
72 	return CLK / 1000;
73 }
74 
75 /*
76  * Return the current AC97 clock frequency.
77  */
clk_pxa3xx_ac97_getrate(struct clk * clk)78 static unsigned long clk_pxa3xx_ac97_getrate(struct clk *clk)
79 {
80 	unsigned long rate = 312000000;
81 	unsigned long ac97_div;
82 
83 	ac97_div = AC97_DIV;
84 
85 	/* This may loose precision for some rates but won't for the
86 	 * standard 24.576MHz.
87 	 */
88 	rate /= (ac97_div >> 12) & 0x7fff;
89 	rate *= (ac97_div & 0xfff);
90 
91 	return rate;
92 }
93 
94 /*
95  * Return the current HSIO bus clock frequency
96  */
clk_pxa3xx_hsio_getrate(struct clk * clk)97 static unsigned long clk_pxa3xx_hsio_getrate(struct clk *clk)
98 {
99 	unsigned long acsr;
100 	unsigned int hss, hsio_clk;
101 
102 	acsr = ACSR;
103 
104 	hss = (acsr >> 14) & 0x3;
105 	hsio_clk = (acsr & ACCR_D0CS) ? RO_CLK : hss_mult[hss] * BASE_CLK;
106 
107 	return hsio_clk;
108 }
109 
110 /* crystal frequency to static memory controller multiplier (SMCFS) */
111 static unsigned int smcfs_mult[8] = { 6, 0, 8, 0, 0, 16, };
112 static unsigned int df_clkdiv[4] = { 1, 2, 4, 1 };
113 
clk_pxa3xx_smemc_getrate(struct clk * clk)114 static unsigned long clk_pxa3xx_smemc_getrate(struct clk *clk)
115 {
116 	unsigned long acsr = ACSR;
117 	unsigned long memclkcfg = __raw_readl(MEMCLKCFG);
118 
119 	return BASE_CLK * smcfs_mult[(acsr >> 23) & 0x7] /
120 			df_clkdiv[(memclkcfg >> 16) & 0x3];
121 }
122 
clk_pxa3xx_cken_enable(struct clk * clk)123 void clk_pxa3xx_cken_enable(struct clk *clk)
124 {
125 	unsigned long mask = 1ul << (clk->cken & 0x1f);
126 
127 	if (clk->cken < 32)
128 		CKENA |= mask;
129 	else
130 		CKENB |= mask;
131 }
132 
clk_pxa3xx_cken_disable(struct clk * clk)133 void clk_pxa3xx_cken_disable(struct clk *clk)
134 {
135 	unsigned long mask = 1ul << (clk->cken & 0x1f);
136 
137 	if (clk->cken < 32)
138 		CKENA &= ~mask;
139 	else
140 		CKENB &= ~mask;
141 }
142 
143 const struct clkops clk_pxa3xx_cken_ops = {
144 	.enable		= clk_pxa3xx_cken_enable,
145 	.disable	= clk_pxa3xx_cken_disable,
146 };
147 
148 const struct clkops clk_pxa3xx_hsio_ops = {
149 	.enable		= clk_pxa3xx_cken_enable,
150 	.disable	= clk_pxa3xx_cken_disable,
151 	.getrate	= clk_pxa3xx_hsio_getrate,
152 };
153 
154 const struct clkops clk_pxa3xx_ac97_ops = {
155 	.enable		= clk_pxa3xx_cken_enable,
156 	.disable	= clk_pxa3xx_cken_disable,
157 	.getrate	= clk_pxa3xx_ac97_getrate,
158 };
159 
160 const struct clkops clk_pxa3xx_smemc_ops = {
161 	.enable		= clk_pxa3xx_cken_enable,
162 	.disable	= clk_pxa3xx_cken_disable,
163 	.getrate	= clk_pxa3xx_smemc_getrate,
164 };
165 
clk_pout_enable(struct clk * clk)166 static void clk_pout_enable(struct clk *clk)
167 {
168 	OSCC |= OSCC_PEN;
169 }
170 
clk_pout_disable(struct clk * clk)171 static void clk_pout_disable(struct clk *clk)
172 {
173 	OSCC &= ~OSCC_PEN;
174 }
175 
176 const struct clkops clk_pxa3xx_pout_ops = {
177 	.enable		= clk_pout_enable,
178 	.disable	= clk_pout_disable,
179 };
180 
181 #ifdef CONFIG_PM
182 static uint32_t cken[2];
183 static uint32_t accr;
184 
pxa3xx_clock_suspend(struct sys_device * d,pm_message_t state)185 static int pxa3xx_clock_suspend(struct sys_device *d, pm_message_t state)
186 {
187 	cken[0] = CKENA;
188 	cken[1] = CKENB;
189 	accr = ACCR;
190 	return 0;
191 }
192 
pxa3xx_clock_resume(struct sys_device * d)193 static int pxa3xx_clock_resume(struct sys_device *d)
194 {
195 	ACCR = accr;
196 	CKENA = cken[0];
197 	CKENB = cken[1];
198 	return 0;
199 }
200 #else
201 #define pxa3xx_clock_suspend	NULL
202 #define pxa3xx_clock_resume	NULL
203 #endif
204 
205 struct sysdev_class pxa3xx_clock_sysclass = {
206 	.name		= "pxa3xx-clock",
207 	.suspend	= pxa3xx_clock_suspend,
208 	.resume		= pxa3xx_clock_resume,
209 };
210 
pxa3xx_clock_init(void)211 static int __init pxa3xx_clock_init(void)
212 {
213 	if (cpu_is_pxa3xx() || cpu_is_pxa95x())
214 		return sysdev_class_register(&pxa3xx_clock_sysclass);
215 	return 0;
216 }
217 postcore_initcall(pxa3xx_clock_init);
218