xref: /openbmc/linux/arch/arm/mach-omap2/clock.c (revision 519ab8b2)
1 /*
2  *  linux/arch/arm/mach-omap2/clock.c
3  *
4  *  Copyright (C) 2005-2008 Texas Instruments, Inc.
5  *  Copyright (C) 2004-2010 Nokia Corporation
6  *
7  *  Contacts:
8  *  Richard Woodruff <r-woodruff2@ti.com>
9  *  Paul Walmsley
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License version 2 as
13  * published by the Free Software Foundation.
14  */
15 #undef DEBUG
16 
17 #include <linux/kernel.h>
18 #include <linux/export.h>
19 #include <linux/list.h>
20 #include <linux/errno.h>
21 #include <linux/err.h>
22 #include <linux/delay.h>
23 #include <linux/clk-provider.h>
24 #include <linux/io.h>
25 #include <linux/bitops.h>
26 #include <linux/clk-private.h>
27 #include <asm/cpu.h>
28 
29 #include <trace/events/power.h>
30 
31 #include "soc.h"
32 #include "clockdomain.h"
33 #include "clock.h"
34 #include "cm.h"
35 #include "cm2xxx.h"
36 #include "cm3xxx.h"
37 #include "cm-regbits-24xx.h"
38 #include "cm-regbits-34xx.h"
39 #include "common.h"
40 
41 /*
42  * MAX_MODULE_ENABLE_WAIT: maximum of number of microseconds to wait
43  * for a module to indicate that it is no longer in idle
44  */
45 #define MAX_MODULE_ENABLE_WAIT		100000
46 
47 u16 cpu_mask;
48 
49 /*
50  * clkdm_control: if true, then when a clock is enabled in the
51  * hardware, its clockdomain will first be enabled; and when a clock
52  * is disabled in the hardware, its clockdomain will be disabled
53  * afterwards.
54  */
55 static bool clkdm_control = true;
56 
57 static LIST_HEAD(clk_hw_omap_clocks);
58 void __iomem *clk_memmaps[CLK_MAX_MEMMAPS];
59 
60 void omap2_clk_writel(u32 val, struct clk_hw_omap *clk, void __iomem *reg)
61 {
62 	if (clk->flags & MEMMAP_ADDRESSING) {
63 		struct clk_omap_reg *r = (struct clk_omap_reg *)&reg;
64 		writel_relaxed(val, clk_memmaps[r->index] + r->offset);
65 	} else {
66 		writel_relaxed(val, reg);
67 	}
68 }
69 
70 u32 omap2_clk_readl(struct clk_hw_omap *clk, void __iomem *reg)
71 {
72 	u32 val;
73 
74 	if (clk->flags & MEMMAP_ADDRESSING) {
75 		struct clk_omap_reg *r = (struct clk_omap_reg *)&reg;
76 		val = readl_relaxed(clk_memmaps[r->index] + r->offset);
77 	} else {
78 		val = readl_relaxed(reg);
79 	}
80 
81 	return val;
82 }
83 
84 /*
85  * Used for clocks that have the same value as the parent clock,
86  * divided by some factor
87  */
88 unsigned long omap_fixed_divisor_recalc(struct clk_hw *hw,
89 		unsigned long parent_rate)
90 {
91 	struct clk_hw_omap *oclk;
92 
93 	if (!hw) {
94 		pr_warn("%s: hw is NULL\n", __func__);
95 		return -EINVAL;
96 	}
97 
98 	oclk = to_clk_hw_omap(hw);
99 
100 	WARN_ON(!oclk->fixed_div);
101 
102 	return parent_rate / oclk->fixed_div;
103 }
104 
105 /*
106  * OMAP2+ specific clock functions
107  */
108 
109 /* Private functions */
110 
111 
112 /**
113  * _wait_idlest_generic - wait for a module to leave the idle state
114  * @clk: module clock to wait for (needed for register offsets)
115  * @reg: virtual address of module IDLEST register
116  * @mask: value to mask against to determine if the module is active
117  * @idlest: idle state indicator (0 or 1) for the clock
118  * @name: name of the clock (for printk)
119  *
120  * Wait for a module to leave idle, where its idle-status register is
121  * not inside the CM module.  Returns 1 if the module left idle
122  * promptly, or 0 if the module did not leave idle before the timeout
123  * elapsed.  XXX Deprecated - should be moved into drivers for the
124  * individual IP block that the IDLEST register exists in.
125  */
126 static int _wait_idlest_generic(struct clk_hw_omap *clk, void __iomem *reg,
127 				u32 mask, u8 idlest, const char *name)
128 {
129 	int i = 0, ena = 0;
130 
131 	ena = (idlest) ? 0 : mask;
132 
133 	omap_test_timeout(((omap2_clk_readl(clk, reg) & mask) == ena),
134 			  MAX_MODULE_ENABLE_WAIT, i);
135 
136 	if (i < MAX_MODULE_ENABLE_WAIT)
137 		pr_debug("omap clock: module associated with clock %s ready after %d loops\n",
138 			 name, i);
139 	else
140 		pr_err("omap clock: module associated with clock %s didn't enable in %d tries\n",
141 		       name, MAX_MODULE_ENABLE_WAIT);
142 
143 	return (i < MAX_MODULE_ENABLE_WAIT) ? 1 : 0;
144 };
145 
146 /**
147  * _omap2_module_wait_ready - wait for an OMAP module to leave IDLE
148  * @clk: struct clk * belonging to the module
149  *
150  * If the necessary clocks for the OMAP hardware IP block that
151  * corresponds to clock @clk are enabled, then wait for the module to
152  * indicate readiness (i.e., to leave IDLE).  This code does not
153  * belong in the clock code and will be moved in the medium term to
154  * module-dependent code.  No return value.
155  */
156 static void _omap2_module_wait_ready(struct clk_hw_omap *clk)
157 {
158 	void __iomem *companion_reg, *idlest_reg;
159 	u8 other_bit, idlest_bit, idlest_val, idlest_reg_id;
160 	s16 prcm_mod;
161 	int r;
162 
163 	/* Not all modules have multiple clocks that their IDLEST depends on */
164 	if (clk->ops->find_companion) {
165 		clk->ops->find_companion(clk, &companion_reg, &other_bit);
166 		if (!(omap2_clk_readl(clk, companion_reg) & (1 << other_bit)))
167 			return;
168 	}
169 
170 	clk->ops->find_idlest(clk, &idlest_reg, &idlest_bit, &idlest_val);
171 	r = cm_split_idlest_reg(idlest_reg, &prcm_mod, &idlest_reg_id);
172 	if (r) {
173 		/* IDLEST register not in the CM module */
174 		_wait_idlest_generic(clk, idlest_reg, (1 << idlest_bit),
175 				     idlest_val, __clk_get_name(clk->hw.clk));
176 	} else {
177 		cm_wait_module_ready(prcm_mod, idlest_reg_id, idlest_bit);
178 	};
179 }
180 
181 /* Public functions */
182 
183 /**
184  * omap2_init_clk_clkdm - look up a clockdomain name, store pointer in clk
185  * @clk: OMAP clock struct ptr to use
186  *
187  * Convert a clockdomain name stored in a struct clk 'clk' into a
188  * clockdomain pointer, and save it into the struct clk.  Intended to be
189  * called during clk_register().  No return value.
190  */
191 void omap2_init_clk_clkdm(struct clk_hw *hw)
192 {
193 	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
194 	struct clockdomain *clkdm;
195 	const char *clk_name;
196 
197 	if (!clk->clkdm_name)
198 		return;
199 
200 	clk_name = __clk_get_name(hw->clk);
201 
202 	clkdm = clkdm_lookup(clk->clkdm_name);
203 	if (clkdm) {
204 		pr_debug("clock: associated clk %s to clkdm %s\n",
205 			 clk_name, clk->clkdm_name);
206 		clk->clkdm = clkdm;
207 	} else {
208 		pr_debug("clock: could not associate clk %s to clkdm %s\n",
209 			 clk_name, clk->clkdm_name);
210 	}
211 }
212 
213 /**
214  * omap2_clk_disable_clkdm_control - disable clkdm control on clk enable/disable
215  *
216  * Prevent the OMAP clock code from calling into the clockdomain code
217  * when a hardware clock in that clockdomain is enabled or disabled.
218  * Intended to be called at init time from omap*_clk_init().  No
219  * return value.
220  */
221 void __init omap2_clk_disable_clkdm_control(void)
222 {
223 	clkdm_control = false;
224 }
225 
226 /**
227  * omap2_clk_dflt_find_companion - find companion clock to @clk
228  * @clk: struct clk * to find the companion clock of
229  * @other_reg: void __iomem ** to return the companion clock CM_*CLKEN va in
230  * @other_bit: u8 ** to return the companion clock bit shift in
231  *
232  * Note: We don't need special code here for INVERT_ENABLE for the
233  * time being since INVERT_ENABLE only applies to clocks enabled by
234  * CM_CLKEN_PLL
235  *
236  * Convert CM_ICLKEN* <-> CM_FCLKEN*.  This conversion assumes it's
237  * just a matter of XORing the bits.
238  *
239  * Some clocks don't have companion clocks.  For example, modules with
240  * only an interface clock (such as MAILBOXES) don't have a companion
241  * clock.  Right now, this code relies on the hardware exporting a bit
242  * in the correct companion register that indicates that the
243  * nonexistent 'companion clock' is active.  Future patches will
244  * associate this type of code with per-module data structures to
245  * avoid this issue, and remove the casts.  No return value.
246  */
247 void omap2_clk_dflt_find_companion(struct clk_hw_omap *clk,
248 			void __iomem **other_reg, u8 *other_bit)
249 {
250 	u32 r;
251 
252 	/*
253 	 * Convert CM_ICLKEN* <-> CM_FCLKEN*.  This conversion assumes
254 	 * it's just a matter of XORing the bits.
255 	 */
256 	r = ((__force u32)clk->enable_reg ^ (CM_FCLKEN ^ CM_ICLKEN));
257 
258 	*other_reg = (__force void __iomem *)r;
259 	*other_bit = clk->enable_bit;
260 }
261 
262 /**
263  * omap2_clk_dflt_find_idlest - find CM_IDLEST reg va, bit shift for @clk
264  * @clk: struct clk * to find IDLEST info for
265  * @idlest_reg: void __iomem ** to return the CM_IDLEST va in
266  * @idlest_bit: u8 * to return the CM_IDLEST bit shift in
267  * @idlest_val: u8 * to return the idle status indicator
268  *
269  * Return the CM_IDLEST register address and bit shift corresponding
270  * to the module that "owns" this clock.  This default code assumes
271  * that the CM_IDLEST bit shift is the CM_*CLKEN bit shift, and that
272  * the IDLEST register address ID corresponds to the CM_*CLKEN
273  * register address ID (e.g., that CM_FCLKEN2 corresponds to
274  * CM_IDLEST2).  This is not true for all modules.  No return value.
275  */
276 void omap2_clk_dflt_find_idlest(struct clk_hw_omap *clk,
277 		void __iomem **idlest_reg, u8 *idlest_bit, u8 *idlest_val)
278 {
279 	u32 r;
280 
281 	r = (((__force u32)clk->enable_reg & ~0xf0) | 0x20);
282 	*idlest_reg = (__force void __iomem *)r;
283 	*idlest_bit = clk->enable_bit;
284 
285 	/*
286 	 * 24xx uses 0 to indicate not ready, and 1 to indicate ready.
287 	 * 34xx reverses this, just to keep us on our toes
288 	 * AM35xx uses both, depending on the module.
289 	 */
290 	if (cpu_is_omap24xx())
291 		*idlest_val = OMAP24XX_CM_IDLEST_VAL;
292 	else if (cpu_is_omap34xx())
293 		*idlest_val = OMAP34XX_CM_IDLEST_VAL;
294 	else
295 		BUG();
296 
297 }
298 
299 /**
300  * omap2_dflt_clk_enable - enable a clock in the hardware
301  * @hw: struct clk_hw * of the clock to enable
302  *
303  * Enable the clock @hw in the hardware.  We first call into the OMAP
304  * clockdomain code to "enable" the corresponding clockdomain if this
305  * is the first enabled user of the clockdomain.  Then program the
306  * hardware to enable the clock.  Then wait for the IP block that uses
307  * this clock to leave idle (if applicable).  Returns the error value
308  * from clkdm_clk_enable() if it terminated with an error, or -EINVAL
309  * if @hw has a null clock enable_reg, or zero upon success.
310  */
311 int omap2_dflt_clk_enable(struct clk_hw *hw)
312 {
313 	struct clk_hw_omap *clk;
314 	u32 v;
315 	int ret = 0;
316 
317 	clk = to_clk_hw_omap(hw);
318 
319 	if (clkdm_control && clk->clkdm) {
320 		ret = clkdm_clk_enable(clk->clkdm, hw->clk);
321 		if (ret) {
322 			WARN(1, "%s: could not enable %s's clockdomain %s: %d\n",
323 			     __func__, __clk_get_name(hw->clk),
324 			     clk->clkdm->name, ret);
325 			return ret;
326 		}
327 	}
328 
329 	if (unlikely(clk->enable_reg == NULL)) {
330 		pr_err("%s: %s missing enable_reg\n", __func__,
331 		       __clk_get_name(hw->clk));
332 		ret = -EINVAL;
333 		goto err;
334 	}
335 
336 	/* FIXME should not have INVERT_ENABLE bit here */
337 	v = omap2_clk_readl(clk, clk->enable_reg);
338 	if (clk->flags & INVERT_ENABLE)
339 		v &= ~(1 << clk->enable_bit);
340 	else
341 		v |= (1 << clk->enable_bit);
342 	omap2_clk_writel(v, clk, clk->enable_reg);
343 	v = omap2_clk_readl(clk, clk->enable_reg); /* OCP barrier */
344 
345 	if (clk->ops && clk->ops->find_idlest)
346 		_omap2_module_wait_ready(clk);
347 
348 	return 0;
349 
350 err:
351 	if (clkdm_control && clk->clkdm)
352 		clkdm_clk_disable(clk->clkdm, hw->clk);
353 	return ret;
354 }
355 
356 /**
357  * omap2_dflt_clk_disable - disable a clock in the hardware
358  * @hw: struct clk_hw * of the clock to disable
359  *
360  * Disable the clock @hw in the hardware, and call into the OMAP
361  * clockdomain code to "disable" the corresponding clockdomain if all
362  * clocks/hwmods in that clockdomain are now disabled.  No return
363  * value.
364  */
365 void omap2_dflt_clk_disable(struct clk_hw *hw)
366 {
367 	struct clk_hw_omap *clk;
368 	u32 v;
369 
370 	clk = to_clk_hw_omap(hw);
371 	if (!clk->enable_reg) {
372 		/*
373 		 * 'independent' here refers to a clock which is not
374 		 * controlled by its parent.
375 		 */
376 		pr_err("%s: independent clock %s has no enable_reg\n",
377 		       __func__, __clk_get_name(hw->clk));
378 		return;
379 	}
380 
381 	v = omap2_clk_readl(clk, clk->enable_reg);
382 	if (clk->flags & INVERT_ENABLE)
383 		v |= (1 << clk->enable_bit);
384 	else
385 		v &= ~(1 << clk->enable_bit);
386 	omap2_clk_writel(v, clk, clk->enable_reg);
387 	/* No OCP barrier needed here since it is a disable operation */
388 
389 	if (clkdm_control && clk->clkdm)
390 		clkdm_clk_disable(clk->clkdm, hw->clk);
391 }
392 
393 /**
394  * omap2_clkops_enable_clkdm - increment usecount on clkdm of @hw
395  * @hw: struct clk_hw * of the clock being enabled
396  *
397  * Increment the usecount of the clockdomain of the clock pointed to
398  * by @hw; if the usecount is 1, the clockdomain will be "enabled."
399  * Only needed for clocks that don't use omap2_dflt_clk_enable() as
400  * their enable function pointer.  Passes along the return value of
401  * clkdm_clk_enable(), -EINVAL if @hw is not associated with a
402  * clockdomain, or 0 if clock framework-based clockdomain control is
403  * not implemented.
404  */
405 int omap2_clkops_enable_clkdm(struct clk_hw *hw)
406 {
407 	struct clk_hw_omap *clk;
408 	int ret = 0;
409 
410 	clk = to_clk_hw_omap(hw);
411 
412 	if (unlikely(!clk->clkdm)) {
413 		pr_err("%s: %s: no clkdm set ?!\n", __func__,
414 		       __clk_get_name(hw->clk));
415 		return -EINVAL;
416 	}
417 
418 	if (unlikely(clk->enable_reg))
419 		pr_err("%s: %s: should use dflt_clk_enable ?!\n", __func__,
420 		       __clk_get_name(hw->clk));
421 
422 	if (!clkdm_control) {
423 		pr_err("%s: %s: clkfw-based clockdomain control disabled ?!\n",
424 		       __func__, __clk_get_name(hw->clk));
425 		return 0;
426 	}
427 
428 	ret = clkdm_clk_enable(clk->clkdm, hw->clk);
429 	WARN(ret, "%s: could not enable %s's clockdomain %s: %d\n",
430 	     __func__, __clk_get_name(hw->clk), clk->clkdm->name, ret);
431 
432 	return ret;
433 }
434 
435 /**
436  * omap2_clkops_disable_clkdm - decrement usecount on clkdm of @hw
437  * @hw: struct clk_hw * of the clock being disabled
438  *
439  * Decrement the usecount of the clockdomain of the clock pointed to
440  * by @hw; if the usecount is 0, the clockdomain will be "disabled."
441  * Only needed for clocks that don't use omap2_dflt_clk_disable() as their
442  * disable function pointer.  No return value.
443  */
444 void omap2_clkops_disable_clkdm(struct clk_hw *hw)
445 {
446 	struct clk_hw_omap *clk;
447 
448 	clk = to_clk_hw_omap(hw);
449 
450 	if (unlikely(!clk->clkdm)) {
451 		pr_err("%s: %s: no clkdm set ?!\n", __func__,
452 		       __clk_get_name(hw->clk));
453 		return;
454 	}
455 
456 	if (unlikely(clk->enable_reg))
457 		pr_err("%s: %s: should use dflt_clk_disable ?!\n", __func__,
458 		       __clk_get_name(hw->clk));
459 
460 	if (!clkdm_control) {
461 		pr_err("%s: %s: clkfw-based clockdomain control disabled ?!\n",
462 		       __func__, __clk_get_name(hw->clk));
463 		return;
464 	}
465 
466 	clkdm_clk_disable(clk->clkdm, hw->clk);
467 }
468 
469 /**
470  * omap2_dflt_clk_is_enabled - is clock enabled in the hardware?
471  * @hw: struct clk_hw * to check
472  *
473  * Return 1 if the clock represented by @hw is enabled in the
474  * hardware, or 0 otherwise.  Intended for use in the struct
475  * clk_ops.is_enabled function pointer.
476  */
477 int omap2_dflt_clk_is_enabled(struct clk_hw *hw)
478 {
479 	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
480 	u32 v;
481 
482 	v = omap2_clk_readl(clk, clk->enable_reg);
483 
484 	if (clk->flags & INVERT_ENABLE)
485 		v ^= BIT(clk->enable_bit);
486 
487 	v &= BIT(clk->enable_bit);
488 
489 	return v ? 1 : 0;
490 }
491 
492 static int __initdata mpurate;
493 
494 /*
495  * By default we use the rate set by the bootloader.
496  * You can override this with mpurate= cmdline option.
497  */
498 static int __init omap_clk_setup(char *str)
499 {
500 	get_option(&str, &mpurate);
501 
502 	if (!mpurate)
503 		return 1;
504 
505 	if (mpurate < 1000)
506 		mpurate *= 1000000;
507 
508 	return 1;
509 }
510 __setup("mpurate=", omap_clk_setup);
511 
512 /**
513  * omap2_init_clk_hw_omap_clocks - initialize an OMAP clock
514  * @clk: struct clk * to initialize
515  *
516  * Add an OMAP clock @clk to the internal list of OMAP clocks.  Used
517  * temporarily for autoidle handling, until this support can be
518  * integrated into the common clock framework code in some way.  No
519  * return value.
520  */
521 void omap2_init_clk_hw_omap_clocks(struct clk *clk)
522 {
523 	struct clk_hw_omap *c;
524 
525 	if (__clk_get_flags(clk) & CLK_IS_BASIC)
526 		return;
527 
528 	c = to_clk_hw_omap(__clk_get_hw(clk));
529 	list_add(&c->node, &clk_hw_omap_clocks);
530 }
531 
532 /**
533  * omap2_clk_enable_autoidle_all - enable autoidle on all OMAP clocks that
534  * support it
535  *
536  * Enable clock autoidle on all OMAP clocks that have allow_idle
537  * function pointers associated with them.  This function is intended
538  * to be temporary until support for this is added to the common clock
539  * code.  Returns 0.
540  */
541 int omap2_clk_enable_autoidle_all(void)
542 {
543 	struct clk_hw_omap *c;
544 
545 	list_for_each_entry(c, &clk_hw_omap_clocks, node)
546 		if (c->ops && c->ops->allow_idle)
547 			c->ops->allow_idle(c);
548 
549 	of_ti_clk_allow_autoidle_all();
550 
551 	return 0;
552 }
553 
554 /**
555  * omap2_clk_disable_autoidle_all - disable autoidle on all OMAP clocks that
556  * support it
557  *
558  * Disable clock autoidle on all OMAP clocks that have allow_idle
559  * function pointers associated with them.  This function is intended
560  * to be temporary until support for this is added to the common clock
561  * code.  Returns 0.
562  */
563 int omap2_clk_disable_autoidle_all(void)
564 {
565 	struct clk_hw_omap *c;
566 
567 	list_for_each_entry(c, &clk_hw_omap_clocks, node)
568 		if (c->ops && c->ops->deny_idle)
569 			c->ops->deny_idle(c);
570 
571 	of_ti_clk_deny_autoidle_all();
572 
573 	return 0;
574 }
575 
576 /**
577  * omap2_clk_deny_idle - disable autoidle on an OMAP clock
578  * @clk: struct clk * to disable autoidle for
579  *
580  * Disable autoidle on an OMAP clock.
581  */
582 int omap2_clk_deny_idle(struct clk *clk)
583 {
584 	struct clk_hw_omap *c;
585 
586 	if (__clk_get_flags(clk) & CLK_IS_BASIC)
587 		return -EINVAL;
588 
589 	c = to_clk_hw_omap(__clk_get_hw(clk));
590 	if (c->ops && c->ops->deny_idle)
591 		c->ops->deny_idle(c);
592 	return 0;
593 }
594 
595 /**
596  * omap2_clk_allow_idle - enable autoidle on an OMAP clock
597  * @clk: struct clk * to enable autoidle for
598  *
599  * Enable autoidle on an OMAP clock.
600  */
601 int omap2_clk_allow_idle(struct clk *clk)
602 {
603 	struct clk_hw_omap *c;
604 
605 	if (__clk_get_flags(clk) & CLK_IS_BASIC)
606 		return -EINVAL;
607 
608 	c = to_clk_hw_omap(__clk_get_hw(clk));
609 	if (c->ops && c->ops->allow_idle)
610 		c->ops->allow_idle(c);
611 	return 0;
612 }
613 
614 /**
615  * omap2_clk_enable_init_clocks - prepare & enable a list of clocks
616  * @clk_names: ptr to an array of strings of clock names to enable
617  * @num_clocks: number of clock names in @clk_names
618  *
619  * Prepare and enable a list of clocks, named by @clk_names.  No
620  * return value. XXX Deprecated; only needed until these clocks are
621  * properly claimed and enabled by the drivers or core code that uses
622  * them.  XXX What code disables & calls clk_put on these clocks?
623  */
624 void omap2_clk_enable_init_clocks(const char **clk_names, u8 num_clocks)
625 {
626 	struct clk *init_clk;
627 	int i;
628 
629 	for (i = 0; i < num_clocks; i++) {
630 		init_clk = clk_get(NULL, clk_names[i]);
631 		clk_prepare_enable(init_clk);
632 	}
633 }
634 
635 const struct clk_hw_omap_ops clkhwops_wait = {
636 	.find_idlest	= omap2_clk_dflt_find_idlest,
637 	.find_companion	= omap2_clk_dflt_find_companion,
638 };
639 
640 /**
641  * omap_clocks_register - register an array of omap_clk
642  * @ocs: pointer to an array of omap_clk to register
643  */
644 void __init omap_clocks_register(struct omap_clk oclks[], int cnt)
645 {
646 	struct omap_clk *c;
647 
648 	for (c = oclks; c < oclks + cnt; c++) {
649 		clkdev_add(&c->lk);
650 		if (!__clk_init(NULL, c->lk.clk))
651 			omap2_init_clk_hw_omap_clocks(c->lk.clk);
652 	}
653 }
654 
655 /**
656  * omap2_clk_switch_mpurate_at_boot - switch ARM MPU rate by boot-time argument
657  * @mpurate_ck_name: clk name of the clock to change rate
658  *
659  * Change the ARM MPU clock rate to the rate specified on the command
660  * line, if one was specified.  @mpurate_ck_name should be
661  * "virt_prcm_set" on OMAP2xxx and "dpll1_ck" on OMAP34xx/OMAP36xx.
662  * XXX Does not handle voltage scaling - on OMAP2xxx this is currently
663  * handled by the virt_prcm_set clock, but this should be handled by
664  * the OPP layer.  XXX This is intended to be handled by the OPP layer
665  * code in the near future and should be removed from the clock code.
666  * Returns -EINVAL if 'mpurate' is zero or if clk_set_rate() rejects
667  * the rate, -ENOENT if the struct clk referred to by @mpurate_ck_name
668  * cannot be found, or 0 upon success.
669  */
670 int __init omap2_clk_switch_mpurate_at_boot(const char *mpurate_ck_name)
671 {
672 	struct clk *mpurate_ck;
673 	int r;
674 
675 	if (!mpurate)
676 		return -EINVAL;
677 
678 	mpurate_ck = clk_get(NULL, mpurate_ck_name);
679 	if (WARN(IS_ERR(mpurate_ck), "Failed to get %s.\n", mpurate_ck_name))
680 		return -ENOENT;
681 
682 	r = clk_set_rate(mpurate_ck, mpurate);
683 	if (r < 0) {
684 		WARN(1, "clock: %s: unable to set MPU rate to %d: %d\n",
685 		     mpurate_ck_name, mpurate, r);
686 		clk_put(mpurate_ck);
687 		return -EINVAL;
688 	}
689 
690 	calibrate_delay();
691 	clk_put(mpurate_ck);
692 
693 	return 0;
694 }
695 
696 /**
697  * omap2_clk_print_new_rates - print summary of current clock tree rates
698  * @hfclkin_ck_name: clk name for the off-chip HF oscillator
699  * @core_ck_name: clk name for the on-chip CORE_CLK
700  * @mpu_ck_name: clk name for the ARM MPU clock
701  *
702  * Prints a short message to the console with the HFCLKIN oscillator
703  * rate, the rate of the CORE clock, and the rate of the ARM MPU clock.
704  * Called by the boot-time MPU rate switching code.   XXX This is intended
705  * to be handled by the OPP layer code in the near future and should be
706  * removed from the clock code.  No return value.
707  */
708 void __init omap2_clk_print_new_rates(const char *hfclkin_ck_name,
709 				      const char *core_ck_name,
710 				      const char *mpu_ck_name)
711 {
712 	struct clk *hfclkin_ck, *core_ck, *mpu_ck;
713 	unsigned long hfclkin_rate;
714 
715 	mpu_ck = clk_get(NULL, mpu_ck_name);
716 	if (WARN(IS_ERR(mpu_ck), "clock: failed to get %s.\n", mpu_ck_name))
717 		return;
718 
719 	core_ck = clk_get(NULL, core_ck_name);
720 	if (WARN(IS_ERR(core_ck), "clock: failed to get %s.\n", core_ck_name))
721 		return;
722 
723 	hfclkin_ck = clk_get(NULL, hfclkin_ck_name);
724 	if (WARN(IS_ERR(hfclkin_ck), "Failed to get %s.\n", hfclkin_ck_name))
725 		return;
726 
727 	hfclkin_rate = clk_get_rate(hfclkin_ck);
728 
729 	pr_info("Switched to new clocking rate (Crystal/Core/MPU): %ld.%01ld/%ld/%ld MHz\n",
730 		(hfclkin_rate / 1000000), ((hfclkin_rate / 100000) % 10),
731 		(clk_get_rate(core_ck) / 1000000),
732 		(clk_get_rate(mpu_ck) / 1000000));
733 }
734