diff options
Diffstat (limited to 'arch/arm/mach-s3c2410/s3c2410-clock.c')
-rw-r--r-- | arch/arm/mach-s3c2410/s3c2410-clock.c | 263 |
1 files changed, 263 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c2410/s3c2410-clock.c b/arch/arm/mach-s3c2410/s3c2410-clock.c new file mode 100644 index 000000000000..fd17c60e1132 --- /dev/null +++ b/arch/arm/mach-s3c2410/s3c2410-clock.c | |||
@@ -0,0 +1,263 @@ | |||
1 | /* linux/arch/arm/mach-s3c2410/clock.c | ||
2 | * | ||
3 | * Copyright (c) 2006 Simtec Electronics | ||
4 | * Ben Dooks <ben@simtec.co.uk> | ||
5 | * | ||
6 | * S3C2410,S3C2440,S3C2442 Clock control support | ||
7 | * | ||
8 | * This program is free software; you can redistribute it and/or modify | ||
9 | * it under the terms of the GNU General Public License as published by | ||
10 | * the Free Software Foundation; either version 2 of the License, or | ||
11 | * (at your option) any later version. | ||
12 | * | ||
13 | * This program is distributed in the hope that it will be useful, | ||
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
16 | * GNU General Public License for more details. | ||
17 | * | ||
18 | * You should have received a copy of the GNU General Public License | ||
19 | * along with this program; if not, write to the Free Software | ||
20 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | ||
21 | */ | ||
22 | |||
23 | #include <linux/init.h> | ||
24 | #include <linux/module.h> | ||
25 | #include <linux/kernel.h> | ||
26 | #include <linux/list.h> | ||
27 | #include <linux/errno.h> | ||
28 | #include <linux/err.h> | ||
29 | #include <linux/sysdev.h> | ||
30 | #include <linux/clk.h> | ||
31 | #include <linux/mutex.h> | ||
32 | #include <linux/delay.h> | ||
33 | |||
34 | #include <asm/hardware.h> | ||
35 | #include <asm/io.h> | ||
36 | |||
37 | #include <asm/arch/regs-clock.h> | ||
38 | #include <asm/arch/regs-gpio.h> | ||
39 | |||
40 | #include "clock.h" | ||
41 | #include "cpu.h" | ||
42 | |||
43 | int s3c2410_clkcon_enable(struct clk *clk, int enable) | ||
44 | { | ||
45 | unsigned int clocks = clk->ctrlbit; | ||
46 | unsigned long clkcon; | ||
47 | |||
48 | clkcon = __raw_readl(S3C2410_CLKCON); | ||
49 | |||
50 | if (enable) | ||
51 | clkcon |= clocks; | ||
52 | else | ||
53 | clkcon &= ~clocks; | ||
54 | |||
55 | /* ensure none of the special function bits set */ | ||
56 | clkcon &= ~(S3C2410_CLKCON_IDLE|S3C2410_CLKCON_POWER); | ||
57 | |||
58 | __raw_writel(clkcon, S3C2410_CLKCON); | ||
59 | |||
60 | return 0; | ||
61 | } | ||
62 | |||
63 | static int s3c2410_upll_enable(struct clk *clk, int enable) | ||
64 | { | ||
65 | unsigned long clkslow = __raw_readl(S3C2410_CLKSLOW); | ||
66 | unsigned long orig = clkslow; | ||
67 | |||
68 | if (enable) | ||
69 | clkslow &= ~S3C2410_CLKSLOW_UCLK_OFF; | ||
70 | else | ||
71 | clkslow |= S3C2410_CLKSLOW_UCLK_OFF; | ||
72 | |||
73 | __raw_writel(clkslow, S3C2410_CLKSLOW); | ||
74 | |||
75 | /* if we started the UPLL, then allow to settle */ | ||
76 | |||
77 | if (enable && (orig & S3C2410_CLKSLOW_UCLK_OFF)) | ||
78 | udelay(200); | ||
79 | |||
80 | return 0; | ||
81 | } | ||
82 | |||
83 | /* standard clock definitions */ | ||
84 | |||
85 | static struct clk init_clocks_disable[] = { | ||
86 | { | ||
87 | .name = "nand", | ||
88 | .id = -1, | ||
89 | .parent = &clk_h, | ||
90 | .enable = s3c2410_clkcon_enable, | ||
91 | .ctrlbit = S3C2410_CLKCON_NAND, | ||
92 | }, { | ||
93 | .name = "sdi", | ||
94 | .id = -1, | ||
95 | .parent = &clk_p, | ||
96 | .enable = s3c2410_clkcon_enable, | ||
97 | .ctrlbit = S3C2410_CLKCON_SDI, | ||
98 | }, { | ||
99 | .name = "adc", | ||
100 | .id = -1, | ||
101 | .parent = &clk_p, | ||
102 | .enable = s3c2410_clkcon_enable, | ||
103 | .ctrlbit = S3C2410_CLKCON_ADC, | ||
104 | }, { | ||
105 | .name = "i2c", | ||
106 | .id = -1, | ||
107 | .parent = &clk_p, | ||
108 | .enable = s3c2410_clkcon_enable, | ||
109 | .ctrlbit = S3C2410_CLKCON_IIC, | ||
110 | }, { | ||
111 | .name = "iis", | ||
112 | .id = -1, | ||
113 | .parent = &clk_p, | ||
114 | .enable = s3c2410_clkcon_enable, | ||
115 | .ctrlbit = S3C2410_CLKCON_IIS, | ||
116 | }, { | ||
117 | .name = "spi", | ||
118 | .id = -1, | ||
119 | .parent = &clk_p, | ||
120 | .enable = s3c2410_clkcon_enable, | ||
121 | .ctrlbit = S3C2410_CLKCON_SPI, | ||
122 | } | ||
123 | }; | ||
124 | |||
125 | static struct clk init_clocks[] = { | ||
126 | { | ||
127 | .name = "lcd", | ||
128 | .id = -1, | ||
129 | .parent = &clk_h, | ||
130 | .enable = s3c2410_clkcon_enable, | ||
131 | .ctrlbit = S3C2410_CLKCON_LCDC, | ||
132 | }, { | ||
133 | .name = "gpio", | ||
134 | .id = -1, | ||
135 | .parent = &clk_p, | ||
136 | .enable = s3c2410_clkcon_enable, | ||
137 | .ctrlbit = S3C2410_CLKCON_GPIO, | ||
138 | }, { | ||
139 | .name = "usb-host", | ||
140 | .id = -1, | ||
141 | .parent = &clk_h, | ||
142 | .enable = s3c2410_clkcon_enable, | ||
143 | .ctrlbit = S3C2410_CLKCON_USBH, | ||
144 | }, { | ||
145 | .name = "usb-device", | ||
146 | .id = -1, | ||
147 | .parent = &clk_h, | ||
148 | .enable = s3c2410_clkcon_enable, | ||
149 | .ctrlbit = S3C2410_CLKCON_USBD, | ||
150 | }, { | ||
151 | .name = "timers", | ||
152 | .id = -1, | ||
153 | .parent = &clk_p, | ||
154 | .enable = s3c2410_clkcon_enable, | ||
155 | .ctrlbit = S3C2410_CLKCON_PWMT, | ||
156 | }, { | ||
157 | .name = "uart", | ||
158 | .id = 0, | ||
159 | .parent = &clk_p, | ||
160 | .enable = s3c2410_clkcon_enable, | ||
161 | .ctrlbit = S3C2410_CLKCON_UART0, | ||
162 | }, { | ||
163 | .name = "uart", | ||
164 | .id = 1, | ||
165 | .parent = &clk_p, | ||
166 | .enable = s3c2410_clkcon_enable, | ||
167 | .ctrlbit = S3C2410_CLKCON_UART1, | ||
168 | }, { | ||
169 | .name = "uart", | ||
170 | .id = 2, | ||
171 | .parent = &clk_p, | ||
172 | .enable = s3c2410_clkcon_enable, | ||
173 | .ctrlbit = S3C2410_CLKCON_UART2, | ||
174 | }, { | ||
175 | .name = "rtc", | ||
176 | .id = -1, | ||
177 | .parent = &clk_p, | ||
178 | .enable = s3c2410_clkcon_enable, | ||
179 | .ctrlbit = S3C2410_CLKCON_RTC, | ||
180 | }, { | ||
181 | .name = "watchdog", | ||
182 | .id = -1, | ||
183 | .parent = &clk_p, | ||
184 | .ctrlbit = 0, | ||
185 | } | ||
186 | }; | ||
187 | |||
188 | /* s3c2410_baseclk_add() | ||
189 | * | ||
190 | * Add all the clocks used by the s3c2410 or compatible CPUs | ||
191 | * such as the S3C2440 and S3C2442. | ||
192 | * | ||
193 | * We cannot use a system device as we are needed before any | ||
194 | * of the init-calls that initialise the devices are actually | ||
195 | * done. | ||
196 | */ | ||
197 | |||
198 | int __init s3c2410_baseclk_add(void) | ||
199 | { | ||
200 | unsigned long clkslow = __raw_readl(S3C2410_CLKSLOW); | ||
201 | unsigned long clkcon = __raw_readl(S3C2410_CLKCON); | ||
202 | struct clk *clkp; | ||
203 | struct clk *xtal; | ||
204 | int ret; | ||
205 | int ptr; | ||
206 | |||
207 | clk_upll.enable = s3c2410_upll_enable; | ||
208 | |||
209 | if (s3c24xx_register_clock(&clk_usb_bus) < 0) | ||
210 | printk(KERN_ERR "failed to register usb bus clock\n"); | ||
211 | |||
212 | /* register clocks from clock array */ | ||
213 | |||
214 | clkp = init_clocks; | ||
215 | for (ptr = 0; ptr < ARRAY_SIZE(init_clocks); ptr++, clkp++) { | ||
216 | /* ensure that we note the clock state */ | ||
217 | |||
218 | clkp->usage = clkcon & clkp->ctrlbit ? 1 : 0; | ||
219 | |||
220 | ret = s3c24xx_register_clock(clkp); | ||
221 | if (ret < 0) { | ||
222 | printk(KERN_ERR "Failed to register clock %s (%d)\n", | ||
223 | clkp->name, ret); | ||
224 | } | ||
225 | } | ||
226 | |||
227 | /* We must be careful disabling the clocks we are not intending to | ||
228 | * be using at boot time, as subsytems such as the LCD which do | ||
229 | * their own DMA requests to the bus can cause the system to lockup | ||
230 | * if they where in the middle of requesting bus access. | ||
231 | * | ||
232 | * Disabling the LCD clock if the LCD is active is very dangerous, | ||
233 | * and therefore the bootloader should be careful to not enable | ||
234 | * the LCD clock if it is not needed. | ||
235 | */ | ||
236 | |||
237 | /* install (and disable) the clocks we do not need immediately */ | ||
238 | |||
239 | clkp = init_clocks_disable; | ||
240 | for (ptr = 0; ptr < ARRAY_SIZE(init_clocks_disable); ptr++, clkp++) { | ||
241 | |||
242 | ret = s3c24xx_register_clock(clkp); | ||
243 | if (ret < 0) { | ||
244 | printk(KERN_ERR "Failed to register clock %s (%d)\n", | ||
245 | clkp->name, ret); | ||
246 | } | ||
247 | |||
248 | s3c2410_clkcon_enable(clkp, 0); | ||
249 | } | ||
250 | |||
251 | /* show the clock-slow value */ | ||
252 | |||
253 | xtal = clk_get(NULL, "xtal"); | ||
254 | |||
255 | printk("CLOCK: Slow mode (%ld.%ld MHz), %s, MPLL %s, UPLL %s\n", | ||
256 | print_mhz(clk_get_rate(xtal) / | ||
257 | ( 2 * S3C2410_CLKSLOW_GET_SLOWVAL(clkslow))), | ||
258 | (clkslow & S3C2410_CLKSLOW_SLOW) ? "slow" : "fast", | ||
259 | (clkslow & S3C2410_CLKSLOW_MPLL_OFF) ? "off" : "on", | ||
260 | (clkslow & S3C2410_CLKSLOW_UCLK_OFF) ? "off" : "on"); | ||
261 | |||
262 | return 0; | ||
263 | } | ||