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Merge 2.6.38-rc5 into staging-next
[deliverable/linux.git] / arch / arm / mach-mxs / clock-mx23.c
1 /*
2 * Copyright (C) 2009-2010 Freescale Semiconductor, Inc. All Rights Reserved.
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 as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19 #include <linux/mm.h>
20 #include <linux/delay.h>
21 #include <linux/clk.h>
22 #include <linux/io.h>
23 #include <linux/jiffies.h>
24 #include <linux/clkdev.h>
25
26 #include <asm/clkdev.h>
27 #include <asm/div64.h>
28
29 #include <mach/mx23.h>
30 #include <mach/common.h>
31 #include <mach/clock.h>
32
33 #include "regs-clkctrl-mx23.h"
34
35 #define CLKCTRL_BASE_ADDR MX23_IO_ADDRESS(MX23_CLKCTRL_BASE_ADDR)
36 #define DIGCTRL_BASE_ADDR MX23_IO_ADDRESS(MX23_DIGCTL_BASE_ADDR)
37
38 #define PARENT_RATE_SHIFT 8
39
40 static int _raw_clk_enable(struct clk *clk)
41 {
42 u32 reg;
43
44 if (clk->enable_reg) {
45 reg = __raw_readl(clk->enable_reg);
46 reg &= ~(1 << clk->enable_shift);
47 __raw_writel(reg, clk->enable_reg);
48 }
49
50 return 0;
51 }
52
53 static void _raw_clk_disable(struct clk *clk)
54 {
55 u32 reg;
56
57 if (clk->enable_reg) {
58 reg = __raw_readl(clk->enable_reg);
59 reg |= 1 << clk->enable_shift;
60 __raw_writel(reg, clk->enable_reg);
61 }
62 }
63
64 /*
65 * ref_xtal_clk
66 */
67 static unsigned long ref_xtal_clk_get_rate(struct clk *clk)
68 {
69 return 24000000;
70 }
71
72 static struct clk ref_xtal_clk = {
73 .get_rate = ref_xtal_clk_get_rate,
74 };
75
76 /*
77 * pll_clk
78 */
79 static unsigned long pll_clk_get_rate(struct clk *clk)
80 {
81 return 480000000;
82 }
83
84 static int pll_clk_enable(struct clk *clk)
85 {
86 __raw_writel(BM_CLKCTRL_PLLCTRL0_POWER |
87 BM_CLKCTRL_PLLCTRL0_EN_USB_CLKS,
88 CLKCTRL_BASE_ADDR + HW_CLKCTRL_PLLCTRL0_SET);
89
90 /* Only a 10us delay is need. PLLCTRL1 LOCK bitfied is only a timer
91 * and is incorrect (excessive). Per definition of the PLLCTRL0
92 * POWER field, waiting at least 10us.
93 */
94 udelay(10);
95
96 return 0;
97 }
98
99 static void pll_clk_disable(struct clk *clk)
100 {
101 __raw_writel(BM_CLKCTRL_PLLCTRL0_POWER |
102 BM_CLKCTRL_PLLCTRL0_EN_USB_CLKS,
103 CLKCTRL_BASE_ADDR + HW_CLKCTRL_PLLCTRL0_CLR);
104 }
105
106 static struct clk pll_clk = {
107 .get_rate = pll_clk_get_rate,
108 .enable = pll_clk_enable,
109 .disable = pll_clk_disable,
110 .parent = &ref_xtal_clk,
111 };
112
113 /*
114 * ref_clk
115 */
116 #define _CLK_GET_RATE_REF(name, sr, ss) \
117 static unsigned long name##_get_rate(struct clk *clk) \
118 { \
119 unsigned long parent_rate; \
120 u32 reg, div; \
121 \
122 reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_##sr); \
123 div = (reg >> BP_CLKCTRL_##sr##_##ss##FRAC) & 0x3f; \
124 parent_rate = clk_get_rate(clk->parent); \
125 \
126 return SH_DIV((parent_rate >> PARENT_RATE_SHIFT) * 18, \
127 div, PARENT_RATE_SHIFT); \
128 }
129
130 _CLK_GET_RATE_REF(ref_cpu_clk, FRAC, CPU)
131 _CLK_GET_RATE_REF(ref_emi_clk, FRAC, EMI)
132 _CLK_GET_RATE_REF(ref_pix_clk, FRAC, PIX)
133 _CLK_GET_RATE_REF(ref_io_clk, FRAC, IO)
134
135 #define _DEFINE_CLOCK_REF(name, er, es) \
136 static struct clk name = { \
137 .enable_reg = CLKCTRL_BASE_ADDR + HW_CLKCTRL_##er, \
138 .enable_shift = BP_CLKCTRL_##er##_CLKGATE##es, \
139 .get_rate = name##_get_rate, \
140 .enable = _raw_clk_enable, \
141 .disable = _raw_clk_disable, \
142 .parent = &pll_clk, \
143 }
144
145 _DEFINE_CLOCK_REF(ref_cpu_clk, FRAC, CPU);
146 _DEFINE_CLOCK_REF(ref_emi_clk, FRAC, EMI);
147 _DEFINE_CLOCK_REF(ref_pix_clk, FRAC, PIX);
148 _DEFINE_CLOCK_REF(ref_io_clk, FRAC, IO);
149
150 /*
151 * General clocks
152 *
153 * clk_get_rate
154 */
155 static unsigned long rtc_clk_get_rate(struct clk *clk)
156 {
157 /* ref_xtal_clk is implemented as the only parent */
158 return clk_get_rate(clk->parent) / 768;
159 }
160
161 static unsigned long clk32k_clk_get_rate(struct clk *clk)
162 {
163 return clk->parent->get_rate(clk->parent) / 750;
164 }
165
166 #define _CLK_GET_RATE(name, rs) \
167 static unsigned long name##_get_rate(struct clk *clk) \
168 { \
169 u32 reg, div; \
170 \
171 reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_##rs); \
172 \
173 if (clk->parent == &ref_xtal_clk) \
174 div = (reg & BM_CLKCTRL_##rs##_DIV_XTAL) >> \
175 BP_CLKCTRL_##rs##_DIV_XTAL; \
176 else \
177 div = (reg & BM_CLKCTRL_##rs##_DIV_##rs) >> \
178 BP_CLKCTRL_##rs##_DIV_##rs; \
179 \
180 if (!div) \
181 return -EINVAL; \
182 \
183 return clk_get_rate(clk->parent) / div; \
184 }
185
186 _CLK_GET_RATE(cpu_clk, CPU)
187 _CLK_GET_RATE(emi_clk, EMI)
188
189 #define _CLK_GET_RATE1(name, rs) \
190 static unsigned long name##_get_rate(struct clk *clk) \
191 { \
192 u32 reg, div; \
193 \
194 reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_##rs); \
195 div = (reg & BM_CLKCTRL_##rs##_DIV) >> BP_CLKCTRL_##rs##_DIV; \
196 \
197 if (!div) \
198 return -EINVAL; \
199 \
200 return clk_get_rate(clk->parent) / div; \
201 }
202
203 _CLK_GET_RATE1(hbus_clk, HBUS)
204 _CLK_GET_RATE1(xbus_clk, XBUS)
205 _CLK_GET_RATE1(ssp_clk, SSP)
206 _CLK_GET_RATE1(gpmi_clk, GPMI)
207 _CLK_GET_RATE1(lcdif_clk, PIX)
208
209 #define _CLK_GET_RATE_STUB(name) \
210 static unsigned long name##_get_rate(struct clk *clk) \
211 { \
212 return clk_get_rate(clk->parent); \
213 }
214
215 _CLK_GET_RATE_STUB(uart_clk)
216 _CLK_GET_RATE_STUB(audio_clk)
217 _CLK_GET_RATE_STUB(pwm_clk)
218
219 /*
220 * clk_set_rate
221 */
222 static int cpu_clk_set_rate(struct clk *clk, unsigned long rate)
223 {
224 u32 reg, bm_busy, div_max, d, f, div, frac;
225 unsigned long diff, parent_rate, calc_rate;
226 int i;
227
228 parent_rate = clk_get_rate(clk->parent);
229
230 if (clk->parent == &ref_xtal_clk) {
231 div_max = BM_CLKCTRL_CPU_DIV_XTAL >> BP_CLKCTRL_CPU_DIV_XTAL;
232 bm_busy = BM_CLKCTRL_CPU_BUSY_REF_XTAL;
233 div = DIV_ROUND_UP(parent_rate, rate);
234 if (div == 0 || div > div_max)
235 return -EINVAL;
236 } else {
237 div_max = BM_CLKCTRL_CPU_DIV_CPU >> BP_CLKCTRL_CPU_DIV_CPU;
238 bm_busy = BM_CLKCTRL_CPU_BUSY_REF_CPU;
239 rate >>= PARENT_RATE_SHIFT;
240 parent_rate >>= PARENT_RATE_SHIFT;
241 diff = parent_rate;
242 div = frac = 1;
243 for (d = 1; d <= div_max; d++) {
244 f = parent_rate * 18 / d / rate;
245 if ((parent_rate * 18 / d) % rate)
246 f++;
247 if (f < 18 || f > 35)
248 continue;
249
250 calc_rate = parent_rate * 18 / f / d;
251 if (calc_rate > rate)
252 continue;
253
254 if (rate - calc_rate < diff) {
255 frac = f;
256 div = d;
257 diff = rate - calc_rate;
258 }
259
260 if (diff == 0)
261 break;
262 }
263
264 if (diff == parent_rate)
265 return -EINVAL;
266
267 reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_FRAC);
268 reg &= ~BM_CLKCTRL_FRAC_CPUFRAC;
269 reg |= frac;
270 __raw_writel(reg, CLKCTRL_BASE_ADDR + HW_CLKCTRL_FRAC);
271 }
272
273 reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_CPU);
274 reg &= ~BM_CLKCTRL_CPU_DIV_CPU;
275 reg |= div << BP_CLKCTRL_CPU_DIV_CPU;
276 __raw_writel(reg, CLKCTRL_BASE_ADDR + HW_CLKCTRL_CPU);
277
278 for (i = 10000; i; i--)
279 if (!(__raw_readl(CLKCTRL_BASE_ADDR +
280 HW_CLKCTRL_CPU) & bm_busy))
281 break;
282 if (!i) {
283 pr_err("%s: divider writing timeout\n", __func__);
284 return -ETIMEDOUT;
285 }
286
287 return 0;
288 }
289
290 #define _CLK_SET_RATE(name, dr) \
291 static int name##_set_rate(struct clk *clk, unsigned long rate) \
292 { \
293 u32 reg, div_max, div; \
294 unsigned long parent_rate; \
295 int i; \
296 \
297 parent_rate = clk_get_rate(clk->parent); \
298 div_max = BM_CLKCTRL_##dr##_DIV >> BP_CLKCTRL_##dr##_DIV; \
299 \
300 div = DIV_ROUND_UP(parent_rate, rate); \
301 if (div == 0 || div > div_max) \
302 return -EINVAL; \
303 \
304 reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_##dr); \
305 reg &= ~BM_CLKCTRL_##dr##_DIV; \
306 reg |= div << BP_CLKCTRL_##dr##_DIV; \
307 if (reg & (1 << clk->enable_shift)) { \
308 pr_err("%s: clock is gated\n", __func__); \
309 return -EINVAL; \
310 } \
311 __raw_writel(reg, CLKCTRL_BASE_ADDR + HW_CLKCTRL_##dr); \
312 \
313 for (i = 10000; i; i--) \
314 if (!(__raw_readl(CLKCTRL_BASE_ADDR + \
315 HW_CLKCTRL_##dr) & BM_CLKCTRL_##dr##_BUSY)) \
316 break; \
317 if (!i) { \
318 pr_err("%s: divider writing timeout\n", __func__); \
319 return -ETIMEDOUT; \
320 } \
321 \
322 return 0; \
323 }
324
325 _CLK_SET_RATE(xbus_clk, XBUS)
326 _CLK_SET_RATE(ssp_clk, SSP)
327 _CLK_SET_RATE(gpmi_clk, GPMI)
328 _CLK_SET_RATE(lcdif_clk, PIX)
329
330 #define _CLK_SET_RATE_STUB(name) \
331 static int name##_set_rate(struct clk *clk, unsigned long rate) \
332 { \
333 return -EINVAL; \
334 }
335
336 _CLK_SET_RATE_STUB(emi_clk)
337 _CLK_SET_RATE_STUB(uart_clk)
338 _CLK_SET_RATE_STUB(audio_clk)
339 _CLK_SET_RATE_STUB(pwm_clk)
340 _CLK_SET_RATE_STUB(clk32k_clk)
341
342 /*
343 * clk_set_parent
344 */
345 #define _CLK_SET_PARENT(name, bit) \
346 static int name##_set_parent(struct clk *clk, struct clk *parent) \
347 { \
348 if (parent != clk->parent) { \
349 __raw_writel(BM_CLKCTRL_CLKSEQ_BYPASS_##bit, \
350 CLKCTRL_BASE_ADDR + HW_CLKCTRL_CLKSEQ_TOG); \
351 clk->parent = parent; \
352 } \
353 \
354 return 0; \
355 }
356
357 _CLK_SET_PARENT(cpu_clk, CPU)
358 _CLK_SET_PARENT(emi_clk, EMI)
359 _CLK_SET_PARENT(ssp_clk, SSP)
360 _CLK_SET_PARENT(gpmi_clk, GPMI)
361 _CLK_SET_PARENT(lcdif_clk, PIX)
362
363 #define _CLK_SET_PARENT_STUB(name) \
364 static int name##_set_parent(struct clk *clk, struct clk *parent) \
365 { \
366 if (parent != clk->parent) \
367 return -EINVAL; \
368 else \
369 return 0; \
370 }
371
372 _CLK_SET_PARENT_STUB(uart_clk)
373 _CLK_SET_PARENT_STUB(audio_clk)
374 _CLK_SET_PARENT_STUB(pwm_clk)
375 _CLK_SET_PARENT_STUB(clk32k_clk)
376
377 /*
378 * clk definition
379 */
380 static struct clk cpu_clk = {
381 .get_rate = cpu_clk_get_rate,
382 .set_rate = cpu_clk_set_rate,
383 .set_parent = cpu_clk_set_parent,
384 .parent = &ref_cpu_clk,
385 };
386
387 static struct clk hbus_clk = {
388 .get_rate = hbus_clk_get_rate,
389 .parent = &cpu_clk,
390 };
391
392 static struct clk xbus_clk = {
393 .get_rate = xbus_clk_get_rate,
394 .set_rate = xbus_clk_set_rate,
395 .parent = &ref_xtal_clk,
396 };
397
398 static struct clk rtc_clk = {
399 .get_rate = rtc_clk_get_rate,
400 .parent = &ref_xtal_clk,
401 };
402
403 /* usb_clk gate is controlled in DIGCTRL other than CLKCTRL */
404 static struct clk usb_clk = {
405 .enable_reg = DIGCTRL_BASE_ADDR,
406 .enable_shift = 2,
407 .enable = _raw_clk_enable,
408 .disable = _raw_clk_disable,
409 .parent = &pll_clk,
410 };
411
412 #define _DEFINE_CLOCK(name, er, es, p) \
413 static struct clk name = { \
414 .enable_reg = CLKCTRL_BASE_ADDR + HW_CLKCTRL_##er, \
415 .enable_shift = BP_CLKCTRL_##er##_##es, \
416 .get_rate = name##_get_rate, \
417 .set_rate = name##_set_rate, \
418 .set_parent = name##_set_parent, \
419 .enable = _raw_clk_enable, \
420 .disable = _raw_clk_disable, \
421 .parent = p, \
422 }
423
424 _DEFINE_CLOCK(emi_clk, EMI, CLKGATE, &ref_xtal_clk);
425 _DEFINE_CLOCK(ssp_clk, SSP, CLKGATE, &ref_xtal_clk);
426 _DEFINE_CLOCK(gpmi_clk, GPMI, CLKGATE, &ref_xtal_clk);
427 _DEFINE_CLOCK(lcdif_clk, PIX, CLKGATE, &ref_xtal_clk);
428 _DEFINE_CLOCK(uart_clk, XTAL, UART_CLK_GATE, &ref_xtal_clk);
429 _DEFINE_CLOCK(audio_clk, XTAL, FILT_CLK24M_GATE, &ref_xtal_clk);
430 _DEFINE_CLOCK(pwm_clk, XTAL, PWM_CLK24M_GATE, &ref_xtal_clk);
431 _DEFINE_CLOCK(clk32k_clk, XTAL, TIMROT_CLK32K_GATE, &ref_xtal_clk);
432
433 #define _REGISTER_CLOCK(d, n, c) \
434 { \
435 .dev_id = d, \
436 .con_id = n, \
437 .clk = &c, \
438 },
439
440 static struct clk_lookup lookups[] = {
441 /* for amba bus driver */
442 _REGISTER_CLOCK("duart", "apb_pclk", xbus_clk)
443 /* for amba-pl011 driver */
444 _REGISTER_CLOCK("duart", NULL, uart_clk)
445 _REGISTER_CLOCK("rtc", NULL, rtc_clk)
446 _REGISTER_CLOCK(NULL, "hclk", hbus_clk)
447 _REGISTER_CLOCK(NULL, "usb", usb_clk)
448 _REGISTER_CLOCK(NULL, "audio", audio_clk)
449 _REGISTER_CLOCK(NULL, "pwm", pwm_clk)
450 };
451
452 static int clk_misc_init(void)
453 {
454 u32 reg;
455 int i;
456
457 /* Fix up parent per register setting */
458 reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_CLKSEQ);
459 cpu_clk.parent = (reg & BM_CLKCTRL_CLKSEQ_BYPASS_CPU) ?
460 &ref_xtal_clk : &ref_cpu_clk;
461 emi_clk.parent = (reg & BM_CLKCTRL_CLKSEQ_BYPASS_EMI) ?
462 &ref_xtal_clk : &ref_emi_clk;
463 ssp_clk.parent = (reg & BM_CLKCTRL_CLKSEQ_BYPASS_SSP) ?
464 &ref_xtal_clk : &ref_io_clk;
465 gpmi_clk.parent = (reg & BM_CLKCTRL_CLKSEQ_BYPASS_GPMI) ?
466 &ref_xtal_clk : &ref_io_clk;
467 lcdif_clk.parent = (reg & BM_CLKCTRL_CLKSEQ_BYPASS_PIX) ?
468 &ref_xtal_clk : &ref_pix_clk;
469
470 /* Use int div over frac when both are available */
471 __raw_writel(BM_CLKCTRL_CPU_DIV_XTAL_FRAC_EN,
472 CLKCTRL_BASE_ADDR + HW_CLKCTRL_CPU_CLR);
473 __raw_writel(BM_CLKCTRL_CPU_DIV_CPU_FRAC_EN,
474 CLKCTRL_BASE_ADDR + HW_CLKCTRL_CPU_CLR);
475 __raw_writel(BM_CLKCTRL_HBUS_DIV_FRAC_EN,
476 CLKCTRL_BASE_ADDR + HW_CLKCTRL_HBUS_CLR);
477
478 reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_XBUS);
479 reg &= ~BM_CLKCTRL_XBUS_DIV_FRAC_EN;
480 __raw_writel(reg, CLKCTRL_BASE_ADDR + HW_CLKCTRL_XBUS);
481
482 reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_SSP);
483 reg &= ~BM_CLKCTRL_SSP_DIV_FRAC_EN;
484 __raw_writel(reg, CLKCTRL_BASE_ADDR + HW_CLKCTRL_SSP);
485
486 reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_GPMI);
487 reg &= ~BM_CLKCTRL_GPMI_DIV_FRAC_EN;
488 __raw_writel(reg, CLKCTRL_BASE_ADDR + HW_CLKCTRL_GPMI);
489
490 reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_PIX);
491 reg &= ~BM_CLKCTRL_PIX_DIV_FRAC_EN;
492 __raw_writel(reg, CLKCTRL_BASE_ADDR + HW_CLKCTRL_PIX);
493
494 /*
495 * Set safe hbus clock divider. A divider of 3 ensure that
496 * the Vddd voltage required for the cpu clock is sufficiently
497 * high for the hbus clock.
498 */
499 reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_HBUS);
500 reg &= BM_CLKCTRL_HBUS_DIV;
501 reg |= 3 << BP_CLKCTRL_HBUS_DIV;
502 __raw_writel(reg, CLKCTRL_BASE_ADDR + HW_CLKCTRL_HBUS);
503
504 for (i = 10000; i; i--)
505 if (!(__raw_readl(CLKCTRL_BASE_ADDR +
506 HW_CLKCTRL_HBUS) & BM_CLKCTRL_HBUS_BUSY))
507 break;
508 if (!i) {
509 pr_err("%s: divider writing timeout\n", __func__);
510 return -ETIMEDOUT;
511 }
512
513 /* Gate off cpu clock in WFI for power saving */
514 __raw_writel(BM_CLKCTRL_CPU_INTERRUPT_WAIT,
515 CLKCTRL_BASE_ADDR + HW_CLKCTRL_CPU_SET);
516
517 return 0;
518 }
519
520 int __init mx23_clocks_init(void)
521 {
522 clk_misc_init();
523
524 clk_enable(&cpu_clk);
525 clk_enable(&hbus_clk);
526 clk_enable(&xbus_clk);
527 clk_enable(&emi_clk);
528 clk_enable(&uart_clk);
529
530 clkdev_add_table(lookups, ARRAY_SIZE(lookups));
531
532 mxs_timer_init(&clk32k_clk, MX23_INT_TIMER0);
533
534 return 0;
535 }
Linux kernel - Deliverables
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