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 #include <linux/syscore_ops.h>
14 
15 #include <mach/smemc.h>
16 #include <mach/pxa3xx-regs.h>
17 
18 #include "clock.h"
19 
20 /* Crystal clock: 13MHz */
21 #define BASE_CLK	13000000
22 
23 /* Ring Oscillator Clock: 60MHz */
24 #define RO_CLK		60000000
25 
26 #define ACCR_D0CS	(1 << 26)
27 #define ACCR_PCCE	(1 << 11)
28 
29 /* crystal frequency to HSIO bus frequency multiplier (HSS) */
30 static unsigned char hss_mult[4] = { 8, 12, 16, 24 };
31 
32 /*
33  * Get the clock frequency as reflected by CCSR and the turbo flag.
34  * We assume these values have been applied via a fcs.
35  * If info is not 0 we also display the current settings.
36  */
pxa3xx_get_clk_frequency_khz(int info)37 unsigned int pxa3xx_get_clk_frequency_khz(int info)
38 {
39 	unsigned long acsr, xclkcfg;
40 	unsigned int t, xl, xn, hss, ro, XL, XN, CLK, HSS;
41 
42 	/* Read XCLKCFG register turbo bit */
43 	__asm__ __volatile__("mrc\tp14, 0, %0, c6, c0, 0" : "=r"(xclkcfg));
44 	t = xclkcfg & 0x1;
45 
46 	acsr = ACSR;
47 
48 	xl  = acsr & 0x1f;
49 	xn  = (acsr >> 8) & 0x7;
50 	hss = (acsr >> 14) & 0x3;
51 
52 	XL = xl * BASE_CLK;
53 	XN = xn * XL;
54 
55 	ro = acsr & ACCR_D0CS;
56 
57 	CLK = (ro) ? RO_CLK : ((t) ? XN : XL);
58 	HSS = (ro) ? RO_CLK : hss_mult[hss] * BASE_CLK;
59 
60 	if (info) {
61 		pr_info("RO Mode clock: %d.%02dMHz (%sactive)\n",
62 			RO_CLK / 1000000, (RO_CLK % 1000000) / 10000,
63 			(ro) ? "" : "in");
64 		pr_info("Run Mode clock: %d.%02dMHz (*%d)\n",
65 			XL / 1000000, (XL % 1000000) / 10000, xl);
66 		pr_info("Turbo Mode clock: %d.%02dMHz (*%d, %sactive)\n",
67 			XN / 1000000, (XN % 1000000) / 10000, xn,
68 			(t) ? "" : "in");
69 		pr_info("HSIO bus clock: %d.%02dMHz\n",
70 			HSS / 1000000, (HSS % 1000000) / 10000);
71 	}
72 
73 	return CLK / 1000;
74 }
75 
76 /*
77  * Return the current AC97 clock frequency.
78  */
clk_pxa3xx_ac97_getrate(struct clk * clk)79 static unsigned long clk_pxa3xx_ac97_getrate(struct clk *clk)
80 {
81 	unsigned long rate = 312000000;
82 	unsigned long ac97_div;
83 
84 	ac97_div = AC97_DIV;
85 
86 	/* This may loose precision for some rates but won't for the
87 	 * standard 24.576MHz.
88 	 */
89 	rate /= (ac97_div >> 12) & 0x7fff;
90 	rate *= (ac97_div & 0xfff);
91 
92 	return rate;
93 }
94 
95 /*
96  * Return the current HSIO bus clock frequency
97  */
clk_pxa3xx_hsio_getrate(struct clk * clk)98 static unsigned long clk_pxa3xx_hsio_getrate(struct clk *clk)
99 {
100 	unsigned long acsr;
101 	unsigned int hss, hsio_clk;
102 
103 	acsr = ACSR;
104 
105 	hss = (acsr >> 14) & 0x3;
106 	hsio_clk = (acsr & ACCR_D0CS) ? RO_CLK : hss_mult[hss] * BASE_CLK;
107 
108 	return hsio_clk;
109 }
110 
111 /* crystal frequency to static memory controller multiplier (SMCFS) */
112 static unsigned int smcfs_mult[8] = { 6, 0, 8, 0, 0, 16, };
113 static unsigned int df_clkdiv[4] = { 1, 2, 4, 1 };
114 
clk_pxa3xx_smemc_getrate(struct clk * clk)115 static unsigned long clk_pxa3xx_smemc_getrate(struct clk *clk)
116 {
117 	unsigned long acsr = ACSR;
118 	unsigned long memclkcfg = __raw_readl(MEMCLKCFG);
119 
120 	return BASE_CLK * smcfs_mult[(acsr >> 23) & 0x7] /
121 			df_clkdiv[(memclkcfg >> 16) & 0x3];
122 }
123 
clk_pxa3xx_cken_enable(struct clk * clk)124 void clk_pxa3xx_cken_enable(struct clk *clk)
125 {
126 	unsigned long mask = 1ul << (clk->cken & 0x1f);
127 
128 	if (clk->cken < 32)
129 		CKENA |= mask;
130 	else
131 		CKENB |= mask;
132 }
133 
clk_pxa3xx_cken_disable(struct clk * clk)134 void clk_pxa3xx_cken_disable(struct clk *clk)
135 {
136 	unsigned long mask = 1ul << (clk->cken & 0x1f);
137 
138 	if (clk->cken < 32)
139 		CKENA &= ~mask;
140 	else
141 		CKENB &= ~mask;
142 }
143 
144 const struct clkops clk_pxa3xx_cken_ops = {
145 	.enable		= clk_pxa3xx_cken_enable,
146 	.disable	= clk_pxa3xx_cken_disable,
147 };
148 
149 const struct clkops clk_pxa3xx_hsio_ops = {
150 	.enable		= clk_pxa3xx_cken_enable,
151 	.disable	= clk_pxa3xx_cken_disable,
152 	.getrate	= clk_pxa3xx_hsio_getrate,
153 };
154 
155 const struct clkops clk_pxa3xx_ac97_ops = {
156 	.enable		= clk_pxa3xx_cken_enable,
157 	.disable	= clk_pxa3xx_cken_disable,
158 	.getrate	= clk_pxa3xx_ac97_getrate,
159 };
160 
161 const struct clkops clk_pxa3xx_smemc_ops = {
162 	.enable		= clk_pxa3xx_cken_enable,
163 	.disable	= clk_pxa3xx_cken_disable,
164 	.getrate	= clk_pxa3xx_smemc_getrate,
165 };
166 
clk_pout_enable(struct clk * clk)167 static void clk_pout_enable(struct clk *clk)
168 {
169 	OSCC |= OSCC_PEN;
170 }
171 
clk_pout_disable(struct clk * clk)172 static void clk_pout_disable(struct clk *clk)
173 {
174 	OSCC &= ~OSCC_PEN;
175 }
176 
177 const struct clkops clk_pxa3xx_pout_ops = {
178 	.enable		= clk_pout_enable,
179 	.disable	= clk_pout_disable,
180 };
181 
182 #ifdef CONFIG_PM
183 static uint32_t cken[2];
184 static uint32_t accr;
185 
pxa3xx_clock_suspend(void)186 static int pxa3xx_clock_suspend(void)
187 {
188 	cken[0] = CKENA;
189 	cken[1] = CKENB;
190 	accr = ACCR;
191 	return 0;
192 }
193 
pxa3xx_clock_resume(void)194 static void pxa3xx_clock_resume(void)
195 {
196 	ACCR = accr;
197 	CKENA = cken[0];
198 	CKENB = cken[1];
199 }
200 #else
201 #define pxa3xx_clock_suspend	NULL
202 #define pxa3xx_clock_resume	NULL
203 #endif
204 
205 struct syscore_ops pxa3xx_clock_syscore_ops = {
206 	.suspend	= pxa3xx_clock_suspend,
207 	.resume		= pxa3xx_clock_resume,
208 };
209