1 /* linux/arch/arm/plat-s3c24xx/s3c2443-clock.c
2 *
3 * Copyright (c) 2007, 2010 Simtec Electronics
4 * Ben Dooks <ben@simtec.co.uk>
5 *
6 * S3C2443 Clock control suport - common code
7 */
8
9 #include <linux/init.h>
10 #include <linux/clk.h>
11 #include <linux/io.h>
12
13 #include <mach/regs-s3c2443-clock.h>
14
15 #include <plat/s3c2443.h>
16 #include <plat/clock.h>
17 #include <plat/clock-clksrc.h>
18 #include <plat/cpu.h>
19
20 #include <plat/cpu-freq.h>
21
22
s3c2443_gate(void __iomem * reg,struct clk * clk,int enable)23 static int s3c2443_gate(void __iomem *reg, struct clk *clk, int enable)
24 {
25 u32 ctrlbit = clk->ctrlbit;
26 u32 con = __raw_readl(reg);
27
28 if (enable)
29 con |= ctrlbit;
30 else
31 con &= ~ctrlbit;
32
33 __raw_writel(con, reg);
34 return 0;
35 }
36
s3c2443_clkcon_enable_h(struct clk * clk,int enable)37 int s3c2443_clkcon_enable_h(struct clk *clk, int enable)
38 {
39 return s3c2443_gate(S3C2443_HCLKCON, clk, enable);
40 }
41
s3c2443_clkcon_enable_p(struct clk * clk,int enable)42 int s3c2443_clkcon_enable_p(struct clk *clk, int enable)
43 {
44 return s3c2443_gate(S3C2443_PCLKCON, clk, enable);
45 }
46
s3c2443_clkcon_enable_s(struct clk * clk,int enable)47 int s3c2443_clkcon_enable_s(struct clk *clk, int enable)
48 {
49 return s3c2443_gate(S3C2443_SCLKCON, clk, enable);
50 }
51
52 /* mpllref is a direct descendant of clk_xtal by default, but it is not
53 * elided as the EPLL can be either sourced by the XTAL or EXTCLK and as
54 * such directly equating the two source clocks is impossible.
55 */
56 struct clk clk_mpllref = {
57 .name = "mpllref",
58 .parent = &clk_xtal,
59 .id = -1,
60 };
61
62 static struct clk *clk_epllref_sources[] = {
63 [0] = &clk_mpllref,
64 [1] = &clk_mpllref,
65 [2] = &clk_xtal,
66 [3] = &clk_ext,
67 };
68
69 struct clksrc_clk clk_epllref = {
70 .clk = {
71 .name = "epllref",
72 .id = -1,
73 },
74 .sources = &(struct clksrc_sources) {
75 .sources = clk_epllref_sources,
76 .nr_sources = ARRAY_SIZE(clk_epllref_sources),
77 },
78 .reg_src = { .reg = S3C2443_CLKSRC, .size = 2, .shift = 7 },
79 };
80
81 /* esysclk
82 *
83 * this is sourced from either the EPLL or the EPLLref clock
84 */
85
86 static struct clk *clk_sysclk_sources[] = {
87 [0] = &clk_epllref.clk,
88 [1] = &clk_epll,
89 };
90
91 struct clksrc_clk clk_esysclk = {
92 .clk = {
93 .name = "esysclk",
94 .parent = &clk_epll,
95 .id = -1,
96 },
97 .sources = &(struct clksrc_sources) {
98 .sources = clk_sysclk_sources,
99 .nr_sources = ARRAY_SIZE(clk_sysclk_sources),
100 },
101 .reg_src = { .reg = S3C2443_CLKSRC, .size = 1, .shift = 6 },
102 };
103
s3c2443_getrate_mdivclk(struct clk * clk)104 static unsigned long s3c2443_getrate_mdivclk(struct clk *clk)
105 {
106 unsigned long parent_rate = clk_get_rate(clk->parent);
107 unsigned long div = __raw_readl(S3C2443_CLKDIV0);
108
109 div &= S3C2443_CLKDIV0_EXTDIV_MASK;
110 div >>= (S3C2443_CLKDIV0_EXTDIV_SHIFT-1); /* x2 */
111
112 return parent_rate / (div + 1);
113 }
114
115 static struct clk clk_mdivclk = {
116 .name = "mdivclk",
117 .parent = &clk_mpllref,
118 .id = -1,
119 .ops = &(struct clk_ops) {
120 .get_rate = s3c2443_getrate_mdivclk,
121 },
122 };
123
124 static struct clk *clk_msysclk_sources[] = {
125 [0] = &clk_mpllref,
126 [1] = &clk_mpll,
127 [2] = &clk_mdivclk,
128 [3] = &clk_mpllref,
129 };
130
131 struct clksrc_clk clk_msysclk = {
132 .clk = {
133 .name = "msysclk",
134 .parent = &clk_xtal,
135 .id = -1,
136 },
137 .sources = &(struct clksrc_sources) {
138 .sources = clk_msysclk_sources,
139 .nr_sources = ARRAY_SIZE(clk_msysclk_sources),
140 },
141 .reg_src = { .reg = S3C2443_CLKSRC, .size = 2, .shift = 3 },
142 };
143
144 /* prediv
145 *
146 * this divides the msysclk down to pass to h/p/etc.
147 */
148
s3c2443_prediv_getrate(struct clk * clk)149 static unsigned long s3c2443_prediv_getrate(struct clk *clk)
150 {
151 unsigned long rate = clk_get_rate(clk->parent);
152 unsigned long clkdiv0 = __raw_readl(S3C2443_CLKDIV0);
153
154 clkdiv0 &= S3C2443_CLKDIV0_PREDIV_MASK;
155 clkdiv0 >>= S3C2443_CLKDIV0_PREDIV_SHIFT;
156
157 return rate / (clkdiv0 + 1);
158 }
159
160 static struct clk clk_prediv = {
161 .name = "prediv",
162 .id = -1,
163 .parent = &clk_msysclk.clk,
164 .ops = &(struct clk_ops) {
165 .get_rate = s3c2443_prediv_getrate,
166 },
167 };
168
169 /* usbhost
170 *
171 * usb host bus-clock, usually 48MHz to provide USB bus clock timing
172 */
173
174 static struct clksrc_clk clk_usb_bus_host = {
175 .clk = {
176 .name = "usb-bus-host-parent",
177 .id = -1,
178 .parent = &clk_esysclk.clk,
179 .ctrlbit = S3C2443_SCLKCON_USBHOST,
180 .enable = s3c2443_clkcon_enable_s,
181 },
182 .reg_div = { .reg = S3C2443_CLKDIV1, .size = 2, .shift = 4 },
183 };
184
185 /* common clksrc clocks */
186
187 static struct clksrc_clk clksrc_clks[] = {
188 {
189 /* ART baud-rate clock sourced from esysclk via a divisor */
190 .clk = {
191 .name = "uartclk",
192 .id = -1,
193 .parent = &clk_esysclk.clk,
194 },
195 .reg_div = { .reg = S3C2443_CLKDIV1, .size = 4, .shift = 8 },
196 }, {
197 /* camera interface bus-clock, divided down from esysclk */
198 .clk = {
199 .name = "camif-upll", /* same as 2440 name */
200 .id = -1,
201 .parent = &clk_esysclk.clk,
202 .ctrlbit = S3C2443_SCLKCON_CAMCLK,
203 .enable = s3c2443_clkcon_enable_s,
204 },
205 .reg_div = { .reg = S3C2443_CLKDIV1, .size = 4, .shift = 26 },
206 }, {
207 .clk = {
208 .name = "display-if",
209 .id = -1,
210 .parent = &clk_esysclk.clk,
211 .ctrlbit = S3C2443_SCLKCON_DISPCLK,
212 .enable = s3c2443_clkcon_enable_s,
213 },
214 .reg_div = { .reg = S3C2443_CLKDIV1, .size = 8, .shift = 16 },
215 },
216 };
217
218
219 static struct clk init_clocks_off[] = {
220 {
221 .name = "adc",
222 .id = -1,
223 .parent = &clk_p,
224 .enable = s3c2443_clkcon_enable_p,
225 .ctrlbit = S3C2443_PCLKCON_ADC,
226 }, {
227 .name = "i2c",
228 .id = -1,
229 .parent = &clk_p,
230 .enable = s3c2443_clkcon_enable_p,
231 .ctrlbit = S3C2443_PCLKCON_IIC,
232 }
233 };
234
235 static struct clk init_clocks[] = {
236 {
237 .name = "dma",
238 .id = 0,
239 .parent = &clk_h,
240 .enable = s3c2443_clkcon_enable_h,
241 .ctrlbit = S3C2443_HCLKCON_DMA0,
242 }, {
243 .name = "dma",
244 .id = 1,
245 .parent = &clk_h,
246 .enable = s3c2443_clkcon_enable_h,
247 .ctrlbit = S3C2443_HCLKCON_DMA1,
248 }, {
249 .name = "dma",
250 .id = 2,
251 .parent = &clk_h,
252 .enable = s3c2443_clkcon_enable_h,
253 .ctrlbit = S3C2443_HCLKCON_DMA2,
254 }, {
255 .name = "dma",
256 .id = 3,
257 .parent = &clk_h,
258 .enable = s3c2443_clkcon_enable_h,
259 .ctrlbit = S3C2443_HCLKCON_DMA3,
260 }, {
261 .name = "dma",
262 .id = 4,
263 .parent = &clk_h,
264 .enable = s3c2443_clkcon_enable_h,
265 .ctrlbit = S3C2443_HCLKCON_DMA4,
266 }, {
267 .name = "dma",
268 .id = 5,
269 .parent = &clk_h,
270 .enable = s3c2443_clkcon_enable_h,
271 .ctrlbit = S3C2443_HCLKCON_DMA5,
272 }, {
273 .name = "hsmmc",
274 .id = 1,
275 .parent = &clk_h,
276 .enable = s3c2443_clkcon_enable_h,
277 .ctrlbit = S3C2443_HCLKCON_HSMMC,
278 }, {
279 .name = "gpio",
280 .id = -1,
281 .parent = &clk_p,
282 .enable = s3c2443_clkcon_enable_p,
283 .ctrlbit = S3C2443_PCLKCON_GPIO,
284 }, {
285 .name = "usb-host",
286 .id = -1,
287 .parent = &clk_h,
288 .enable = s3c2443_clkcon_enable_h,
289 .ctrlbit = S3C2443_HCLKCON_USBH,
290 }, {
291 .name = "usb-device",
292 .id = -1,
293 .parent = &clk_h,
294 .enable = s3c2443_clkcon_enable_h,
295 .ctrlbit = S3C2443_HCLKCON_USBD,
296 }, {
297 .name = "lcd",
298 .id = -1,
299 .parent = &clk_h,
300 .enable = s3c2443_clkcon_enable_h,
301 .ctrlbit = S3C2443_HCLKCON_LCDC,
302
303 }, {
304 .name = "timers",
305 .id = -1,
306 .parent = &clk_p,
307 .enable = s3c2443_clkcon_enable_p,
308 .ctrlbit = S3C2443_PCLKCON_PWMT,
309 }, {
310 .name = "cfc",
311 .id = -1,
312 .parent = &clk_h,
313 .enable = s3c2443_clkcon_enable_h,
314 .ctrlbit = S3C2443_HCLKCON_CFC,
315 }, {
316 .name = "ssmc",
317 .id = -1,
318 .parent = &clk_h,
319 .enable = s3c2443_clkcon_enable_h,
320 .ctrlbit = S3C2443_HCLKCON_SSMC,
321 }, {
322 .name = "uart",
323 .id = 0,
324 .parent = &clk_p,
325 .enable = s3c2443_clkcon_enable_p,
326 .ctrlbit = S3C2443_PCLKCON_UART0,
327 }, {
328 .name = "uart",
329 .id = 1,
330 .parent = &clk_p,
331 .enable = s3c2443_clkcon_enable_p,
332 .ctrlbit = S3C2443_PCLKCON_UART1,
333 }, {
334 .name = "uart",
335 .id = 2,
336 .parent = &clk_p,
337 .enable = s3c2443_clkcon_enable_p,
338 .ctrlbit = S3C2443_PCLKCON_UART2,
339 }, {
340 .name = "uart",
341 .id = 3,
342 .parent = &clk_p,
343 .enable = s3c2443_clkcon_enable_p,
344 .ctrlbit = S3C2443_PCLKCON_UART3,
345 }, {
346 .name = "rtc",
347 .id = -1,
348 .parent = &clk_p,
349 .enable = s3c2443_clkcon_enable_p,
350 .ctrlbit = S3C2443_PCLKCON_RTC,
351 }, {
352 .name = "watchdog",
353 .id = -1,
354 .parent = &clk_p,
355 .ctrlbit = S3C2443_PCLKCON_WDT,
356 }, {
357 .name = "ac97",
358 .id = -1,
359 .parent = &clk_p,
360 .ctrlbit = S3C2443_PCLKCON_AC97,
361 }, {
362 .name = "nand",
363 .id = -1,
364 .parent = &clk_h,
365 }, {
366 .name = "usb-bus-host",
367 .id = -1,
368 .parent = &clk_usb_bus_host.clk,
369 }
370 };
371
s3c2443_get_hdiv(unsigned long clkcon0)372 static inline unsigned long s3c2443_get_hdiv(unsigned long clkcon0)
373 {
374 clkcon0 &= S3C2443_CLKDIV0_HCLKDIV_MASK;
375
376 return clkcon0 + 1;
377 }
378
379 /* EPLLCON compatible enough to get on/off information */
380
s3c2443_common_setup_clocks(pll_fn get_mpll,fdiv_fn get_fdiv)381 void __init_or_cpufreq s3c2443_common_setup_clocks(pll_fn get_mpll,
382 fdiv_fn get_fdiv)
383 {
384 unsigned long epllcon = __raw_readl(S3C2443_EPLLCON);
385 unsigned long mpllcon = __raw_readl(S3C2443_MPLLCON);
386 unsigned long clkdiv0 = __raw_readl(S3C2443_CLKDIV0);
387 struct clk *xtal_clk;
388 unsigned long xtal;
389 unsigned long pll;
390 unsigned long fclk;
391 unsigned long hclk;
392 unsigned long pclk;
393 int ptr;
394
395 xtal_clk = clk_get(NULL, "xtal");
396 xtal = clk_get_rate(xtal_clk);
397 clk_put(xtal_clk);
398
399 pll = get_mpll(mpllcon, xtal);
400 clk_msysclk.clk.rate = pll;
401
402 fclk = pll / get_fdiv(clkdiv0);
403 hclk = s3c2443_prediv_getrate(&clk_prediv);
404 hclk /= s3c2443_get_hdiv(clkdiv0);
405 pclk = hclk / ((clkdiv0 & S3C2443_CLKDIV0_HALF_PCLK) ? 2 : 1);
406
407 s3c24xx_setup_clocks(fclk, hclk, pclk);
408
409 printk("CPU: MPLL %s %ld.%03ld MHz, cpu %ld.%03ld MHz, mem %ld.%03ld MHz, pclk %ld.%03ld MHz\n",
410 (mpllcon & S3C2443_PLLCON_OFF) ? "off":"on",
411 print_mhz(pll), print_mhz(fclk),
412 print_mhz(hclk), print_mhz(pclk));
413
414 for (ptr = 0; ptr < ARRAY_SIZE(clksrc_clks); ptr++)
415 s3c_set_clksrc(&clksrc_clks[ptr], true);
416
417 /* ensure usb bus clock is within correct rate of 48MHz */
418
419 if (clk_get_rate(&clk_usb_bus_host.clk) != (48 * 1000 * 1000)) {
420 printk(KERN_INFO "Warning: USB host bus not at 48MHz\n");
421 clk_set_rate(&clk_usb_bus_host.clk, 48*1000*1000);
422 }
423
424 printk("CPU: EPLL %s %ld.%03ld MHz, usb-bus %ld.%03ld MHz\n",
425 (epllcon & S3C2443_PLLCON_OFF) ? "off":"on",
426 print_mhz(clk_get_rate(&clk_epll)),
427 print_mhz(clk_get_rate(&clk_usb_bus)));
428 }
429
430 static struct clk *clks[] __initdata = {
431 &clk_prediv,
432 &clk_mpllref,
433 &clk_mdivclk,
434 &clk_ext,
435 &clk_epll,
436 &clk_usb_bus,
437 };
438
439 static struct clksrc_clk *clksrcs[] __initdata = {
440 &clk_usb_bus_host,
441 &clk_epllref,
442 &clk_esysclk,
443 &clk_msysclk,
444 };
445
s3c2443_common_init_clocks(int xtal,pll_fn get_mpll,fdiv_fn get_fdiv)446 void __init s3c2443_common_init_clocks(int xtal, pll_fn get_mpll,
447 fdiv_fn get_fdiv)
448 {
449 int ptr;
450
451 /* s3c2443 parents h and p clocks from prediv */
452 clk_h.parent = &clk_prediv;
453 clk_p.parent = &clk_prediv;
454
455 clk_usb_bus.parent = &clk_usb_bus_host.clk;
456 clk_epll.parent = &clk_epllref.clk;
457
458 s3c24xx_register_baseclocks(xtal);
459 s3c24xx_register_clocks(clks, ARRAY_SIZE(clks));
460
461 for (ptr = 0; ptr < ARRAY_SIZE(clksrcs); ptr++)
462 s3c_register_clksrc(clksrcs[ptr], 1);
463
464 s3c_register_clksrc(clksrc_clks, ARRAY_SIZE(clksrc_clks));
465 s3c_register_clocks(init_clocks, ARRAY_SIZE(init_clocks));
466
467 /* See s3c2443/etc notes on disabling clocks at init time */
468 s3c_register_clocks(init_clocks_off, ARRAY_SIZE(init_clocks_off));
469 s3c_disable_clocks(init_clocks_off, ARRAY_SIZE(init_clocks_off));
470
471 s3c2443_common_setup_clocks(get_mpll, get_fdiv);
472 }
473