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 if (clk->cken < 64)
131 CKENB |= mask;
132 else
133 CKENC |= mask;
134 }
135
clk_pxa3xx_cken_disable(struct clk * clk)136 void clk_pxa3xx_cken_disable(struct clk *clk)
137 {
138 unsigned long mask = 1ul << (clk->cken & 0x1f);
139
140 if (clk->cken < 32)
141 CKENA &= ~mask;
142 else if (clk->cken < 64)
143 CKENB &= ~mask;
144 else
145 CKENC &= ~mask;
146 }
147
148 const struct clkops clk_pxa3xx_cken_ops = {
149 .enable = clk_pxa3xx_cken_enable,
150 .disable = clk_pxa3xx_cken_disable,
151 };
152
153 const struct clkops clk_pxa3xx_hsio_ops = {
154 .enable = clk_pxa3xx_cken_enable,
155 .disable = clk_pxa3xx_cken_disable,
156 .getrate = clk_pxa3xx_hsio_getrate,
157 };
158
159 const struct clkops clk_pxa3xx_ac97_ops = {
160 .enable = clk_pxa3xx_cken_enable,
161 .disable = clk_pxa3xx_cken_disable,
162 .getrate = clk_pxa3xx_ac97_getrate,
163 };
164
165 const struct clkops clk_pxa3xx_smemc_ops = {
166 .enable = clk_pxa3xx_cken_enable,
167 .disable = clk_pxa3xx_cken_disable,
168 .getrate = clk_pxa3xx_smemc_getrate,
169 };
170
clk_pout_enable(struct clk * clk)171 static void clk_pout_enable(struct clk *clk)
172 {
173 OSCC |= OSCC_PEN;
174 }
175
clk_pout_disable(struct clk * clk)176 static void clk_pout_disable(struct clk *clk)
177 {
178 OSCC &= ~OSCC_PEN;
179 }
180
181 const struct clkops clk_pxa3xx_pout_ops = {
182 .enable = clk_pout_enable,
183 .disable = clk_pout_disable,
184 };
185
186 #ifdef CONFIG_PM
187 static uint32_t cken[2];
188 static uint32_t accr;
189
pxa3xx_clock_suspend(void)190 static int pxa3xx_clock_suspend(void)
191 {
192 cken[0] = CKENA;
193 cken[1] = CKENB;
194 accr = ACCR;
195 return 0;
196 }
197
pxa3xx_clock_resume(void)198 static void pxa3xx_clock_resume(void)
199 {
200 ACCR = accr;
201 CKENA = cken[0];
202 CKENB = cken[1];
203 }
204 #else
205 #define pxa3xx_clock_suspend NULL
206 #define pxa3xx_clock_resume NULL
207 #endif
208
209 struct syscore_ops pxa3xx_clock_syscore_ops = {
210 .suspend = pxa3xx_clock_suspend,
211 .resume = pxa3xx_clock_resume,
212 };
213