xref: /openbmc/linux/arch/arm/mach-omap1/clock.c (revision b627b4ed)
1 /*
2  *  linux/arch/arm/mach-omap1/clock.c
3  *
4  *  Copyright (C) 2004 - 2005 Nokia corporation
5  *  Written by Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>
6  *
7  *  Modified to use omap shared clock framework by
8  *  Tony Lindgren <tony@atomide.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  */
14 #include <linux/module.h>
15 #include <linux/kernel.h>
16 #include <linux/list.h>
17 #include <linux/errno.h>
18 #include <linux/err.h>
19 #include <linux/clk.h>
20 #include <linux/io.h>
21 
22 #include <asm/mach-types.h>
23 #include <asm/clkdev.h>
24 
25 #include <mach/cpu.h>
26 #include <mach/usb.h>
27 #include <mach/clock.h>
28 #include <mach/sram.h>
29 
30 static const struct clkops clkops_generic;
31 static const struct clkops clkops_uart;
32 static const struct clkops clkops_dspck;
33 
34 #include "clock.h"
35 
36 static int clk_omap1_dummy_enable(struct clk *clk)
37 {
38 	return 0;
39 }
40 
41 static void clk_omap1_dummy_disable(struct clk *clk)
42 {
43 }
44 
45 static const struct clkops clkops_dummy = {
46 	.enable = clk_omap1_dummy_enable,
47 	.disable = clk_omap1_dummy_disable,
48 };
49 
50 static struct clk dummy_ck = {
51 	.name	= "dummy",
52 	.ops	= &clkops_dummy,
53 	.flags	= RATE_FIXED,
54 };
55 
56 struct omap_clk {
57 	u32		cpu;
58 	struct clk_lookup lk;
59 };
60 
61 #define CLK(dev, con, ck, cp) 		\
62 	{				\
63 		 .cpu = cp,		\
64 		.lk = {			\
65 			.dev_id = dev,	\
66 			.con_id = con,	\
67 			.clk = ck,	\
68 		},			\
69 	}
70 
71 #define CK_310	(1 << 0)
72 #define CK_730	(1 << 1)
73 #define CK_1510	(1 << 2)
74 #define CK_16XX	(1 << 3)
75 
76 static struct omap_clk omap_clks[] = {
77 	/* non-ULPD clocks */
78 	CLK(NULL,	"ck_ref",	&ck_ref,	CK_16XX | CK_1510 | CK_310),
79 	CLK(NULL,	"ck_dpll1",	&ck_dpll1,	CK_16XX | CK_1510 | CK_310),
80 	/* CK_GEN1 clocks */
81 	CLK(NULL,	"ck_dpll1out",	&ck_dpll1out.clk, CK_16XX),
82 	CLK(NULL,	"ck_sossi",	&sossi_ck,	CK_16XX),
83 	CLK(NULL,	"arm_ck",	&arm_ck,	CK_16XX | CK_1510 | CK_310),
84 	CLK(NULL,	"armper_ck",	&armper_ck.clk,	CK_16XX | CK_1510 | CK_310),
85 	CLK(NULL,	"arm_gpio_ck",	&arm_gpio_ck,	CK_1510 | CK_310),
86 	CLK(NULL,	"armxor_ck",	&armxor_ck.clk,	CK_16XX | CK_1510 | CK_310),
87 	CLK(NULL,	"armtim_ck",	&armtim_ck.clk,	CK_16XX | CK_1510 | CK_310),
88 	CLK("omap_wdt",	"fck",		&armwdt_ck.clk,	CK_16XX | CK_1510 | CK_310),
89 	CLK("omap_wdt",	"ick",		&armper_ck.clk,	CK_16XX),
90 	CLK("omap_wdt", "ick",		&dummy_ck,	CK_1510 | CK_310),
91 	CLK(NULL,	"arminth_ck",	&arminth_ck1510, CK_1510 | CK_310),
92 	CLK(NULL,	"arminth_ck",	&arminth_ck16xx, CK_16XX),
93 	/* CK_GEN2 clocks */
94 	CLK(NULL,	"dsp_ck",	&dsp_ck,	CK_16XX | CK_1510 | CK_310),
95 	CLK(NULL,	"dspmmu_ck",	&dspmmu_ck,	CK_16XX | CK_1510 | CK_310),
96 	CLK(NULL,	"dspper_ck",	&dspper_ck,	CK_16XX | CK_1510 | CK_310),
97 	CLK(NULL,	"dspxor_ck",	&dspxor_ck,	CK_16XX | CK_1510 | CK_310),
98 	CLK(NULL,	"dsptim_ck",	&dsptim_ck,	CK_16XX | CK_1510 | CK_310),
99 	/* CK_GEN3 clocks */
100 	CLK(NULL,	"tc_ck",	&tc_ck.clk,	CK_16XX | CK_1510 | CK_310 | CK_730),
101 	CLK(NULL,	"tipb_ck",	&tipb_ck,	CK_1510 | CK_310),
102 	CLK(NULL,	"l3_ocpi_ck",	&l3_ocpi_ck,	CK_16XX),
103 	CLK(NULL,	"tc1_ck",	&tc1_ck,	CK_16XX),
104 	CLK(NULL,	"tc2_ck",	&tc2_ck,	CK_16XX),
105 	CLK(NULL,	"dma_ck",	&dma_ck,	CK_16XX | CK_1510 | CK_310),
106 	CLK(NULL,	"dma_lcdfree_ck", &dma_lcdfree_ck, CK_16XX),
107 	CLK(NULL,	"api_ck",	&api_ck.clk,	CK_16XX | CK_1510 | CK_310),
108 	CLK(NULL,	"lb_ck",	&lb_ck.clk,	CK_1510 | CK_310),
109 	CLK(NULL,	"rhea1_ck",	&rhea1_ck,	CK_16XX),
110 	CLK(NULL,	"rhea2_ck",	&rhea2_ck,	CK_16XX),
111 	CLK(NULL,	"lcd_ck",	&lcd_ck_16xx,	CK_16XX | CK_730),
112 	CLK(NULL,	"lcd_ck",	&lcd_ck_1510.clk, CK_1510 | CK_310),
113 	/* ULPD clocks */
114 	CLK(NULL,	"uart1_ck",	&uart1_1510,	CK_1510 | CK_310),
115 	CLK(NULL,	"uart1_ck",	&uart1_16xx.clk, CK_16XX),
116 	CLK(NULL,	"uart2_ck",	&uart2_ck,	CK_16XX | CK_1510 | CK_310),
117 	CLK(NULL,	"uart3_ck",	&uart3_1510,	CK_1510 | CK_310),
118 	CLK(NULL,	"uart3_ck",	&uart3_16xx.clk, CK_16XX),
119 	CLK(NULL,	"usb_clko",	&usb_clko,	CK_16XX | CK_1510 | CK_310),
120 	CLK(NULL,	"usb_hhc_ck",	&usb_hhc_ck1510, CK_1510 | CK_310),
121 	CLK(NULL,	"usb_hhc_ck",	&usb_hhc_ck16xx, CK_16XX),
122 	CLK(NULL,	"usb_dc_ck",	&usb_dc_ck,	CK_16XX),
123 	CLK(NULL,	"mclk",		&mclk_1510,	CK_1510 | CK_310),
124 	CLK(NULL,	"mclk",		&mclk_16xx,	CK_16XX),
125 	CLK(NULL,	"bclk",		&bclk_1510,	CK_1510 | CK_310),
126 	CLK(NULL,	"bclk",		&bclk_16xx,	CK_16XX),
127 	CLK("mmci-omap.0", "fck",	&mmc1_ck,	CK_16XX | CK_1510 | CK_310),
128 	CLK("mmci-omap.0", "ick",	&armper_ck.clk,	CK_16XX | CK_1510 | CK_310),
129 	CLK("mmci-omap.1", "fck",	&mmc2_ck,	CK_16XX),
130 	CLK("mmci-omap.1", "ick",	&armper_ck.clk,	CK_16XX),
131 	/* Virtual clocks */
132 	CLK(NULL,	"mpu",		&virtual_ck_mpu, CK_16XX | CK_1510 | CK_310),
133 	CLK("i2c_omap.1", "fck",	&i2c_fck,	CK_16XX | CK_1510 | CK_310),
134 	CLK("i2c_omap.1", "ick",	&i2c_ick,	CK_16XX),
135 	CLK("i2c_omap.1", "ick",	&dummy_ck,	CK_1510 | CK_310),
136 	CLK("omap_uwire", "fck",	&armxor_ck.clk,	CK_16XX | CK_1510 | CK_310),
137 	CLK("omap-mcbsp.1", "ick",	&dspper_ck,	CK_16XX),
138 	CLK("omap-mcbsp.1", "ick",	&dummy_ck,	CK_1510 | CK_310),
139 	CLK("omap-mcbsp.2", "ick",	&armper_ck.clk,	CK_16XX),
140 	CLK("omap-mcbsp.2", "ick",	&dummy_ck,	CK_1510 | CK_310),
141 	CLK("omap-mcbsp.3", "ick",	&dspper_ck,	CK_16XX),
142 	CLK("omap-mcbsp.3", "ick",	&dummy_ck,	CK_1510 | CK_310),
143 	CLK("omap-mcbsp.1", "fck",	&dspxor_ck,	CK_16XX | CK_1510 | CK_310),
144 	CLK("omap-mcbsp.2", "fck",	&armper_ck.clk,	CK_16XX | CK_1510 | CK_310),
145 	CLK("omap-mcbsp.3", "fck",	&dspxor_ck,	CK_16XX | CK_1510 | CK_310),
146 };
147 
148 static int omap1_clk_enable_generic(struct clk * clk);
149 static int omap1_clk_enable(struct clk *clk);
150 static void omap1_clk_disable_generic(struct clk * clk);
151 static void omap1_clk_disable(struct clk *clk);
152 
153 __u32 arm_idlect1_mask;
154 
155 /*-------------------------------------------------------------------------
156  * Omap1 specific clock functions
157  *-------------------------------------------------------------------------*/
158 
159 static unsigned long omap1_watchdog_recalc(struct clk *clk)
160 {
161 	return clk->parent->rate / 14;
162 }
163 
164 static unsigned long omap1_uart_recalc(struct clk *clk)
165 {
166 	unsigned int val = __raw_readl(clk->enable_reg);
167 	return val & clk->enable_bit ? 48000000 : 12000000;
168 }
169 
170 static unsigned long omap1_sossi_recalc(struct clk *clk)
171 {
172 	u32 div = omap_readl(MOD_CONF_CTRL_1);
173 
174 	div = (div >> 17) & 0x7;
175 	div++;
176 
177 	return clk->parent->rate / div;
178 }
179 
180 static int omap1_clk_enable_dsp_domain(struct clk *clk)
181 {
182 	int retval;
183 
184 	retval = omap1_clk_enable(&api_ck.clk);
185 	if (!retval) {
186 		retval = omap1_clk_enable_generic(clk);
187 		omap1_clk_disable(&api_ck.clk);
188 	}
189 
190 	return retval;
191 }
192 
193 static void omap1_clk_disable_dsp_domain(struct clk *clk)
194 {
195 	if (omap1_clk_enable(&api_ck.clk) == 0) {
196 		omap1_clk_disable_generic(clk);
197 		omap1_clk_disable(&api_ck.clk);
198 	}
199 }
200 
201 static const struct clkops clkops_dspck = {
202 	.enable		= &omap1_clk_enable_dsp_domain,
203 	.disable	= &omap1_clk_disable_dsp_domain,
204 };
205 
206 static int omap1_clk_enable_uart_functional(struct clk *clk)
207 {
208 	int ret;
209 	struct uart_clk *uclk;
210 
211 	ret = omap1_clk_enable_generic(clk);
212 	if (ret == 0) {
213 		/* Set smart idle acknowledgement mode */
214 		uclk = (struct uart_clk *)clk;
215 		omap_writeb((omap_readb(uclk->sysc_addr) & ~0x10) | 8,
216 			    uclk->sysc_addr);
217 	}
218 
219 	return ret;
220 }
221 
222 static void omap1_clk_disable_uart_functional(struct clk *clk)
223 {
224 	struct uart_clk *uclk;
225 
226 	/* Set force idle acknowledgement mode */
227 	uclk = (struct uart_clk *)clk;
228 	omap_writeb((omap_readb(uclk->sysc_addr) & ~0x18), uclk->sysc_addr);
229 
230 	omap1_clk_disable_generic(clk);
231 }
232 
233 static const struct clkops clkops_uart = {
234 	.enable		= &omap1_clk_enable_uart_functional,
235 	.disable	= &omap1_clk_disable_uart_functional,
236 };
237 
238 static void omap1_clk_allow_idle(struct clk *clk)
239 {
240 	struct arm_idlect1_clk * iclk = (struct arm_idlect1_clk *)clk;
241 
242 	if (!(clk->flags & CLOCK_IDLE_CONTROL))
243 		return;
244 
245 	if (iclk->no_idle_count > 0 && !(--iclk->no_idle_count))
246 		arm_idlect1_mask |= 1 << iclk->idlect_shift;
247 }
248 
249 static void omap1_clk_deny_idle(struct clk *clk)
250 {
251 	struct arm_idlect1_clk * iclk = (struct arm_idlect1_clk *)clk;
252 
253 	if (!(clk->flags & CLOCK_IDLE_CONTROL))
254 		return;
255 
256 	if (iclk->no_idle_count++ == 0)
257 		arm_idlect1_mask &= ~(1 << iclk->idlect_shift);
258 }
259 
260 static __u16 verify_ckctl_value(__u16 newval)
261 {
262 	/* This function checks for following limitations set
263 	 * by the hardware (all conditions must be true):
264 	 * DSPMMU_CK == DSP_CK  or  DSPMMU_CK == DSP_CK/2
265 	 * ARM_CK >= TC_CK
266 	 * DSP_CK >= TC_CK
267 	 * DSPMMU_CK >= TC_CK
268 	 *
269 	 * In addition following rules are enforced:
270 	 * LCD_CK <= TC_CK
271 	 * ARMPER_CK <= TC_CK
272 	 *
273 	 * However, maximum frequencies are not checked for!
274 	 */
275 	__u8 per_exp;
276 	__u8 lcd_exp;
277 	__u8 arm_exp;
278 	__u8 dsp_exp;
279 	__u8 tc_exp;
280 	__u8 dspmmu_exp;
281 
282 	per_exp = (newval >> CKCTL_PERDIV_OFFSET) & 3;
283 	lcd_exp = (newval >> CKCTL_LCDDIV_OFFSET) & 3;
284 	arm_exp = (newval >> CKCTL_ARMDIV_OFFSET) & 3;
285 	dsp_exp = (newval >> CKCTL_DSPDIV_OFFSET) & 3;
286 	tc_exp = (newval >> CKCTL_TCDIV_OFFSET) & 3;
287 	dspmmu_exp = (newval >> CKCTL_DSPMMUDIV_OFFSET) & 3;
288 
289 	if (dspmmu_exp < dsp_exp)
290 		dspmmu_exp = dsp_exp;
291 	if (dspmmu_exp > dsp_exp+1)
292 		dspmmu_exp = dsp_exp+1;
293 	if (tc_exp < arm_exp)
294 		tc_exp = arm_exp;
295 	if (tc_exp < dspmmu_exp)
296 		tc_exp = dspmmu_exp;
297 	if (tc_exp > lcd_exp)
298 		lcd_exp = tc_exp;
299 	if (tc_exp > per_exp)
300 		per_exp = tc_exp;
301 
302 	newval &= 0xf000;
303 	newval |= per_exp << CKCTL_PERDIV_OFFSET;
304 	newval |= lcd_exp << CKCTL_LCDDIV_OFFSET;
305 	newval |= arm_exp << CKCTL_ARMDIV_OFFSET;
306 	newval |= dsp_exp << CKCTL_DSPDIV_OFFSET;
307 	newval |= tc_exp << CKCTL_TCDIV_OFFSET;
308 	newval |= dspmmu_exp << CKCTL_DSPMMUDIV_OFFSET;
309 
310 	return newval;
311 }
312 
313 static int calc_dsor_exp(struct clk *clk, unsigned long rate)
314 {
315 	/* Note: If target frequency is too low, this function will return 4,
316 	 * which is invalid value. Caller must check for this value and act
317 	 * accordingly.
318 	 *
319 	 * Note: This function does not check for following limitations set
320 	 * by the hardware (all conditions must be true):
321 	 * DSPMMU_CK == DSP_CK  or  DSPMMU_CK == DSP_CK/2
322 	 * ARM_CK >= TC_CK
323 	 * DSP_CK >= TC_CK
324 	 * DSPMMU_CK >= TC_CK
325 	 */
326 	unsigned long realrate;
327 	struct clk * parent;
328 	unsigned  dsor_exp;
329 
330 	parent = clk->parent;
331 	if (unlikely(parent == NULL))
332 		return -EIO;
333 
334 	realrate = parent->rate;
335 	for (dsor_exp=0; dsor_exp<4; dsor_exp++) {
336 		if (realrate <= rate)
337 			break;
338 
339 		realrate /= 2;
340 	}
341 
342 	return dsor_exp;
343 }
344 
345 static unsigned long omap1_ckctl_recalc(struct clk *clk)
346 {
347 	/* Calculate divisor encoded as 2-bit exponent */
348 	int dsor = 1 << (3 & (omap_readw(ARM_CKCTL) >> clk->rate_offset));
349 
350 	return clk->parent->rate / dsor;
351 }
352 
353 static unsigned long omap1_ckctl_recalc_dsp_domain(struct clk *clk)
354 {
355 	int dsor;
356 
357 	/* Calculate divisor encoded as 2-bit exponent
358 	 *
359 	 * The clock control bits are in DSP domain,
360 	 * so api_ck is needed for access.
361 	 * Note that DSP_CKCTL virt addr = phys addr, so
362 	 * we must use __raw_readw() instead of omap_readw().
363 	 */
364 	omap1_clk_enable(&api_ck.clk);
365 	dsor = 1 << (3 & (__raw_readw(DSP_CKCTL) >> clk->rate_offset));
366 	omap1_clk_disable(&api_ck.clk);
367 
368 	return clk->parent->rate / dsor;
369 }
370 
371 /* MPU virtual clock functions */
372 static int omap1_select_table_rate(struct clk * clk, unsigned long rate)
373 {
374 	/* Find the highest supported frequency <= rate and switch to it */
375 	struct mpu_rate * ptr;
376 
377 	if (clk != &virtual_ck_mpu)
378 		return -EINVAL;
379 
380 	for (ptr = rate_table; ptr->rate; ptr++) {
381 		if (ptr->xtal != ck_ref.rate)
382 			continue;
383 
384 		/* DPLL1 cannot be reprogrammed without risking system crash */
385 		if (likely(ck_dpll1.rate!=0) && ptr->pll_rate != ck_dpll1.rate)
386 			continue;
387 
388 		/* Can check only after xtal frequency check */
389 		if (ptr->rate <= rate)
390 			break;
391 	}
392 
393 	if (!ptr->rate)
394 		return -EINVAL;
395 
396 	/*
397 	 * In most cases we should not need to reprogram DPLL.
398 	 * Reprogramming the DPLL is tricky, it must be done from SRAM.
399 	 * (on 730, bit 13 must always be 1)
400 	 */
401 	if (cpu_is_omap730())
402 		omap_sram_reprogram_clock(ptr->dpllctl_val, ptr->ckctl_val | 0x2000);
403 	else
404 		omap_sram_reprogram_clock(ptr->dpllctl_val, ptr->ckctl_val);
405 
406 	ck_dpll1.rate = ptr->pll_rate;
407 	return 0;
408 }
409 
410 static int omap1_clk_set_rate_dsp_domain(struct clk *clk, unsigned long rate)
411 {
412 	int dsor_exp;
413 	u16 regval;
414 
415 	dsor_exp = calc_dsor_exp(clk, rate);
416 	if (dsor_exp > 3)
417 		dsor_exp = -EINVAL;
418 	if (dsor_exp < 0)
419 		return dsor_exp;
420 
421 	regval = __raw_readw(DSP_CKCTL);
422 	regval &= ~(3 << clk->rate_offset);
423 	regval |= dsor_exp << clk->rate_offset;
424 	__raw_writew(regval, DSP_CKCTL);
425 	clk->rate = clk->parent->rate / (1 << dsor_exp);
426 
427 	return 0;
428 }
429 
430 static long omap1_clk_round_rate_ckctl_arm(struct clk *clk, unsigned long rate)
431 {
432 	int dsor_exp = calc_dsor_exp(clk, rate);
433 	if (dsor_exp < 0)
434 		return dsor_exp;
435 	if (dsor_exp > 3)
436 		dsor_exp = 3;
437 	return clk->parent->rate / (1 << dsor_exp);
438 }
439 
440 static int omap1_clk_set_rate_ckctl_arm(struct clk *clk, unsigned long rate)
441 {
442 	int dsor_exp;
443 	u16 regval;
444 
445 	dsor_exp = calc_dsor_exp(clk, rate);
446 	if (dsor_exp > 3)
447 		dsor_exp = -EINVAL;
448 	if (dsor_exp < 0)
449 		return dsor_exp;
450 
451 	regval = omap_readw(ARM_CKCTL);
452 	regval &= ~(3 << clk->rate_offset);
453 	regval |= dsor_exp << clk->rate_offset;
454 	regval = verify_ckctl_value(regval);
455 	omap_writew(regval, ARM_CKCTL);
456 	clk->rate = clk->parent->rate / (1 << dsor_exp);
457 	return 0;
458 }
459 
460 static long omap1_round_to_table_rate(struct clk * clk, unsigned long rate)
461 {
462 	/* Find the highest supported frequency <= rate */
463 	struct mpu_rate * ptr;
464 	long  highest_rate;
465 
466 	if (clk != &virtual_ck_mpu)
467 		return -EINVAL;
468 
469 	highest_rate = -EINVAL;
470 
471 	for (ptr = rate_table; ptr->rate; ptr++) {
472 		if (ptr->xtal != ck_ref.rate)
473 			continue;
474 
475 		highest_rate = ptr->rate;
476 
477 		/* Can check only after xtal frequency check */
478 		if (ptr->rate <= rate)
479 			break;
480 	}
481 
482 	return highest_rate;
483 }
484 
485 static unsigned calc_ext_dsor(unsigned long rate)
486 {
487 	unsigned dsor;
488 
489 	/* MCLK and BCLK divisor selection is not linear:
490 	 * freq = 96MHz / dsor
491 	 *
492 	 * RATIO_SEL range: dsor <-> RATIO_SEL
493 	 * 0..6: (RATIO_SEL+2) <-> (dsor-2)
494 	 * 6..48:  (8+(RATIO_SEL-6)*2) <-> ((dsor-8)/2+6)
495 	 * Minimum dsor is 2 and maximum is 96. Odd divisors starting from 9
496 	 * can not be used.
497 	 */
498 	for (dsor = 2; dsor < 96; ++dsor) {
499 		if ((dsor & 1) && dsor > 8)
500 			continue;
501 		if (rate >= 96000000 / dsor)
502 			break;
503 	}
504 	return dsor;
505 }
506 
507 /* Only needed on 1510 */
508 static int omap1_set_uart_rate(struct clk * clk, unsigned long rate)
509 {
510 	unsigned int val;
511 
512 	val = __raw_readl(clk->enable_reg);
513 	if (rate == 12000000)
514 		val &= ~(1 << clk->enable_bit);
515 	else if (rate == 48000000)
516 		val |= (1 << clk->enable_bit);
517 	else
518 		return -EINVAL;
519 	__raw_writel(val, clk->enable_reg);
520 	clk->rate = rate;
521 
522 	return 0;
523 }
524 
525 /* External clock (MCLK & BCLK) functions */
526 static int omap1_set_ext_clk_rate(struct clk * clk, unsigned long rate)
527 {
528 	unsigned dsor;
529 	__u16 ratio_bits;
530 
531 	dsor = calc_ext_dsor(rate);
532 	clk->rate = 96000000 / dsor;
533 	if (dsor > 8)
534 		ratio_bits = ((dsor - 8) / 2 + 6) << 2;
535 	else
536 		ratio_bits = (dsor - 2) << 2;
537 
538 	ratio_bits |= __raw_readw(clk->enable_reg) & ~0xfd;
539 	__raw_writew(ratio_bits, clk->enable_reg);
540 
541 	return 0;
542 }
543 
544 static int omap1_set_sossi_rate(struct clk *clk, unsigned long rate)
545 {
546 	u32 l;
547 	int div;
548 	unsigned long p_rate;
549 
550 	p_rate = clk->parent->rate;
551 	/* Round towards slower frequency */
552 	div = (p_rate + rate - 1) / rate;
553 	div--;
554 	if (div < 0 || div > 7)
555 		return -EINVAL;
556 
557 	l = omap_readl(MOD_CONF_CTRL_1);
558 	l &= ~(7 << 17);
559 	l |= div << 17;
560 	omap_writel(l, MOD_CONF_CTRL_1);
561 
562 	clk->rate = p_rate / (div + 1);
563 
564 	return 0;
565 }
566 
567 static long omap1_round_ext_clk_rate(struct clk * clk, unsigned long rate)
568 {
569 	return 96000000 / calc_ext_dsor(rate);
570 }
571 
572 static void omap1_init_ext_clk(struct clk * clk)
573 {
574 	unsigned dsor;
575 	__u16 ratio_bits;
576 
577 	/* Determine current rate and ensure clock is based on 96MHz APLL */
578 	ratio_bits = __raw_readw(clk->enable_reg) & ~1;
579 	__raw_writew(ratio_bits, clk->enable_reg);
580 
581 	ratio_bits = (ratio_bits & 0xfc) >> 2;
582 	if (ratio_bits > 6)
583 		dsor = (ratio_bits - 6) * 2 + 8;
584 	else
585 		dsor = ratio_bits + 2;
586 
587 	clk-> rate = 96000000 / dsor;
588 }
589 
590 static int omap1_clk_enable(struct clk *clk)
591 {
592 	int ret = 0;
593 
594 	if (clk->usecount++ == 0) {
595 		if (clk->parent) {
596 			ret = omap1_clk_enable(clk->parent);
597 			if (ret)
598 				goto err;
599 
600 			if (clk->flags & CLOCK_NO_IDLE_PARENT)
601 				omap1_clk_deny_idle(clk->parent);
602 		}
603 
604 		ret = clk->ops->enable(clk);
605 		if (ret) {
606 			if (clk->parent)
607 				omap1_clk_disable(clk->parent);
608 			goto err;
609 		}
610 	}
611 	return ret;
612 
613 err:
614 	clk->usecount--;
615 	return ret;
616 }
617 
618 static void omap1_clk_disable(struct clk *clk)
619 {
620 	if (clk->usecount > 0 && !(--clk->usecount)) {
621 		clk->ops->disable(clk);
622 		if (likely(clk->parent)) {
623 			omap1_clk_disable(clk->parent);
624 			if (clk->flags & CLOCK_NO_IDLE_PARENT)
625 				omap1_clk_allow_idle(clk->parent);
626 		}
627 	}
628 }
629 
630 static int omap1_clk_enable_generic(struct clk *clk)
631 {
632 	__u16 regval16;
633 	__u32 regval32;
634 
635 	if (unlikely(clk->enable_reg == NULL)) {
636 		printk(KERN_ERR "clock.c: Enable for %s without enable code\n",
637 		       clk->name);
638 		return -EINVAL;
639 	}
640 
641 	if (clk->flags & ENABLE_REG_32BIT) {
642 		regval32 = __raw_readl(clk->enable_reg);
643 		regval32 |= (1 << clk->enable_bit);
644 		__raw_writel(regval32, clk->enable_reg);
645 	} else {
646 		regval16 = __raw_readw(clk->enable_reg);
647 		regval16 |= (1 << clk->enable_bit);
648 		__raw_writew(regval16, clk->enable_reg);
649 	}
650 
651 	return 0;
652 }
653 
654 static void omap1_clk_disable_generic(struct clk *clk)
655 {
656 	__u16 regval16;
657 	__u32 regval32;
658 
659 	if (clk->enable_reg == NULL)
660 		return;
661 
662 	if (clk->flags & ENABLE_REG_32BIT) {
663 		regval32 = __raw_readl(clk->enable_reg);
664 		regval32 &= ~(1 << clk->enable_bit);
665 		__raw_writel(regval32, clk->enable_reg);
666 	} else {
667 		regval16 = __raw_readw(clk->enable_reg);
668 		regval16 &= ~(1 << clk->enable_bit);
669 		__raw_writew(regval16, clk->enable_reg);
670 	}
671 }
672 
673 static const struct clkops clkops_generic = {
674 	.enable		= &omap1_clk_enable_generic,
675 	.disable	= &omap1_clk_disable_generic,
676 };
677 
678 static long omap1_clk_round_rate(struct clk *clk, unsigned long rate)
679 {
680 	if (clk->flags & RATE_FIXED)
681 		return clk->rate;
682 
683 	if (clk->round_rate != NULL)
684 		return clk->round_rate(clk, rate);
685 
686 	return clk->rate;
687 }
688 
689 static int omap1_clk_set_rate(struct clk *clk, unsigned long rate)
690 {
691 	int  ret = -EINVAL;
692 
693 	if (clk->set_rate)
694 		ret = clk->set_rate(clk, rate);
695 	return ret;
696 }
697 
698 /*-------------------------------------------------------------------------
699  * Omap1 clock reset and init functions
700  *-------------------------------------------------------------------------*/
701 
702 #ifdef CONFIG_OMAP_RESET_CLOCKS
703 
704 static void __init omap1_clk_disable_unused(struct clk *clk)
705 {
706 	__u32 regval32;
707 
708 	/* Clocks in the DSP domain need api_ck. Just assume bootloader
709 	 * has not enabled any DSP clocks */
710 	if (clk->enable_reg == DSP_IDLECT2) {
711 		printk(KERN_INFO "Skipping reset check for DSP domain "
712 		       "clock \"%s\"\n", clk->name);
713 		return;
714 	}
715 
716 	/* Is the clock already disabled? */
717 	if (clk->flags & ENABLE_REG_32BIT)
718 		regval32 = __raw_readl(clk->enable_reg);
719 	else
720 		regval32 = __raw_readw(clk->enable_reg);
721 
722 	if ((regval32 & (1 << clk->enable_bit)) == 0)
723 		return;
724 
725 	/* FIXME: This clock seems to be necessary but no-one
726 	 * has asked for its activation. */
727 	if (clk == &tc2_ck		/* FIX: pm.c (SRAM), CCP, Camera */
728 	    || clk == &ck_dpll1out.clk	/* FIX: SoSSI, SSR */
729 	    || clk == &arm_gpio_ck	/* FIX: GPIO code for 1510 */
730 		) {
731 		printk(KERN_INFO "FIXME: Clock \"%s\" seems unused\n",
732 		       clk->name);
733 		return;
734 	}
735 
736 	printk(KERN_INFO "Disabling unused clock \"%s\"... ", clk->name);
737 	clk->ops->disable(clk);
738 	printk(" done\n");
739 }
740 
741 #else
742 #define omap1_clk_disable_unused	NULL
743 #endif
744 
745 static struct clk_functions omap1_clk_functions = {
746 	.clk_enable		= omap1_clk_enable,
747 	.clk_disable		= omap1_clk_disable,
748 	.clk_round_rate		= omap1_clk_round_rate,
749 	.clk_set_rate		= omap1_clk_set_rate,
750 	.clk_disable_unused	= omap1_clk_disable_unused,
751 };
752 
753 int __init omap1_clk_init(void)
754 {
755 	struct omap_clk *c;
756 	const struct omap_clock_config *info;
757 	int crystal_type = 0; /* Default 12 MHz */
758 	u32 reg, cpu_mask;
759 
760 #ifdef CONFIG_DEBUG_LL
761 	/* Resets some clocks that may be left on from bootloader,
762 	 * but leaves serial clocks on.
763  	 */
764 	omap_writel(0x3 << 29, MOD_CONF_CTRL_0);
765 #endif
766 
767 	/* USB_REQ_EN will be disabled later if necessary (usb_dc_ck) */
768 	reg = omap_readw(SOFT_REQ_REG) & (1 << 4);
769 	omap_writew(reg, SOFT_REQ_REG);
770 	if (!cpu_is_omap15xx())
771 		omap_writew(0, SOFT_REQ_REG2);
772 
773 	clk_init(&omap1_clk_functions);
774 
775 	/* By default all idlect1 clocks are allowed to idle */
776 	arm_idlect1_mask = ~0;
777 
778 	for (c = omap_clks; c < omap_clks + ARRAY_SIZE(omap_clks); c++)
779 		clk_init_one(c->lk.clk);
780 
781 	cpu_mask = 0;
782 	if (cpu_is_omap16xx())
783 		cpu_mask |= CK_16XX;
784 	if (cpu_is_omap1510())
785 		cpu_mask |= CK_1510;
786 	if (cpu_is_omap730())
787 		cpu_mask |= CK_730;
788 	if (cpu_is_omap310())
789 		cpu_mask |= CK_310;
790 
791 	for (c = omap_clks; c < omap_clks + ARRAY_SIZE(omap_clks); c++)
792 		if (c->cpu & cpu_mask) {
793 			clkdev_add(&c->lk);
794 			clk_register(c->lk.clk);
795 		}
796 
797 	info = omap_get_config(OMAP_TAG_CLOCK, struct omap_clock_config);
798 	if (info != NULL) {
799 		if (!cpu_is_omap15xx())
800 			crystal_type = info->system_clock_type;
801 	}
802 
803 #if defined(CONFIG_ARCH_OMAP730)
804 	ck_ref.rate = 13000000;
805 #elif defined(CONFIG_ARCH_OMAP16XX)
806 	if (crystal_type == 2)
807 		ck_ref.rate = 19200000;
808 #endif
809 
810 	printk("Clocks: ARM_SYSST: 0x%04x DPLL_CTL: 0x%04x ARM_CKCTL: 0x%04x\n",
811 	       omap_readw(ARM_SYSST), omap_readw(DPLL_CTL),
812 	       omap_readw(ARM_CKCTL));
813 
814 	/* We want to be in syncronous scalable mode */
815 	omap_writew(0x1000, ARM_SYSST);
816 
817 #ifdef CONFIG_OMAP_CLOCKS_SET_BY_BOOTLOADER
818 	/* Use values set by bootloader. Determine PLL rate and recalculate
819 	 * dependent clocks as if kernel had changed PLL or divisors.
820 	 */
821 	{
822 		unsigned pll_ctl_val = omap_readw(DPLL_CTL);
823 
824 		ck_dpll1.rate = ck_ref.rate; /* Base xtal rate */
825 		if (pll_ctl_val & 0x10) {
826 			/* PLL enabled, apply multiplier and divisor */
827 			if (pll_ctl_val & 0xf80)
828 				ck_dpll1.rate *= (pll_ctl_val & 0xf80) >> 7;
829 			ck_dpll1.rate /= ((pll_ctl_val & 0x60) >> 5) + 1;
830 		} else {
831 			/* PLL disabled, apply bypass divisor */
832 			switch (pll_ctl_val & 0xc) {
833 			case 0:
834 				break;
835 			case 0x4:
836 				ck_dpll1.rate /= 2;
837 				break;
838 			default:
839 				ck_dpll1.rate /= 4;
840 				break;
841 			}
842 		}
843 	}
844 #else
845 	/* Find the highest supported frequency and enable it */
846 	if (omap1_select_table_rate(&virtual_ck_mpu, ~0)) {
847 		printk(KERN_ERR "System frequencies not set. Check your config.\n");
848 		/* Guess sane values (60MHz) */
849 		omap_writew(0x2290, DPLL_CTL);
850 		omap_writew(cpu_is_omap730() ? 0x3005 : 0x1005, ARM_CKCTL);
851 		ck_dpll1.rate = 60000000;
852 	}
853 #endif
854 	propagate_rate(&ck_dpll1);
855 	/* Cache rates for clocks connected to ck_ref (not dpll1) */
856 	propagate_rate(&ck_ref);
857 	printk(KERN_INFO "Clocking rate (xtal/DPLL1/MPU): "
858 		"%ld.%01ld/%ld.%01ld/%ld.%01ld MHz\n",
859 	       ck_ref.rate / 1000000, (ck_ref.rate / 100000) % 10,
860 	       ck_dpll1.rate / 1000000, (ck_dpll1.rate / 100000) % 10,
861 	       arm_ck.rate / 1000000, (arm_ck.rate / 100000) % 10);
862 
863 #if defined(CONFIG_MACH_OMAP_PERSEUS2) || defined(CONFIG_MACH_OMAP_FSAMPLE)
864 	/* Select slicer output as OMAP input clock */
865 	omap_writew(omap_readw(OMAP730_PCC_UPLD_CTRL) & ~0x1, OMAP730_PCC_UPLD_CTRL);
866 #endif
867 
868 	/* Amstrad Delta wants BCLK high when inactive */
869 	if (machine_is_ams_delta())
870 		omap_writel(omap_readl(ULPD_CLOCK_CTRL) |
871 				(1 << SDW_MCLK_INV_BIT),
872 				ULPD_CLOCK_CTRL);
873 
874 	/* Turn off DSP and ARM_TIMXO. Make sure ARM_INTHCK is not divided */
875 	/* (on 730, bit 13 must not be cleared) */
876 	if (cpu_is_omap730())
877 		omap_writew(omap_readw(ARM_CKCTL) & 0x2fff, ARM_CKCTL);
878 	else
879 		omap_writew(omap_readw(ARM_CKCTL) & 0x0fff, ARM_CKCTL);
880 
881 	/* Put DSP/MPUI into reset until needed */
882 	omap_writew(0, ARM_RSTCT1);
883 	omap_writew(1, ARM_RSTCT2);
884 	omap_writew(0x400, ARM_IDLECT1);
885 
886 	/*
887 	 * According to OMAP5910 Erratum SYS_DMA_1, bit DMACK_REQ (bit 8)
888 	 * of the ARM_IDLECT2 register must be set to zero. The power-on
889 	 * default value of this bit is one.
890 	 */
891 	omap_writew(0x0000, ARM_IDLECT2);	/* Turn LCD clock off also */
892 
893 	/*
894 	 * Only enable those clocks we will need, let the drivers
895 	 * enable other clocks as necessary
896 	 */
897 	clk_enable(&armper_ck.clk);
898 	clk_enable(&armxor_ck.clk);
899 	clk_enable(&armtim_ck.clk); /* This should be done by timer code */
900 
901 	if (cpu_is_omap15xx())
902 		clk_enable(&arm_gpio_ck);
903 
904 	return 0;
905 }
906