xref: /openbmc/linux/arch/arm/mach-omap2/clock.c (revision 42ed83f5)
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 <asm/cpu.h>
27 
28 #include <trace/events/power.h>
29 
30 #include "soc.h"
31 #include "clockdomain.h"
32 #include "clock.h"
33 #include "cm.h"
34 #include "cm2xxx.h"
35 #include "cm3xxx.h"
36 #include "cm-regbits-24xx.h"
37 #include "cm-regbits-34xx.h"
38 #include "common.h"
39 
40 /*
41  * MAX_MODULE_ENABLE_WAIT: maximum of number of microseconds to wait
42  * for a module to indicate that it is no longer in idle
43  */
44 #define MAX_MODULE_ENABLE_WAIT		100000
45 
46 u16 cpu_mask;
47 
48 /*
49  * Clock features setup. Used instead of CPU type checks.
50  */
51 struct ti_clk_features ti_clk_features;
52 
53 /* DPLL valid Fint frequency band limits - from 34xx TRM Section 4.7.6.2 */
54 #define OMAP3430_DPLL_FINT_BAND1_MIN	750000
55 #define OMAP3430_DPLL_FINT_BAND1_MAX	2100000
56 #define OMAP3430_DPLL_FINT_BAND2_MIN	7500000
57 #define OMAP3430_DPLL_FINT_BAND2_MAX	21000000
58 
59 /*
60  * DPLL valid Fint frequency range for OMAP36xx and OMAP4xxx.
61  * From device data manual section 4.3 "DPLL and DLL Specifications".
62  */
63 #define OMAP3PLUS_DPLL_FINT_MIN		32000
64 #define OMAP3PLUS_DPLL_FINT_MAX		52000000
65 
66 /*
67  * clkdm_control: if true, then when a clock is enabled in the
68  * hardware, its clockdomain will first be enabled; and when a clock
69  * is disabled in the hardware, its clockdomain will be disabled
70  * afterwards.
71  */
72 static bool clkdm_control = true;
73 
74 static LIST_HEAD(clk_hw_omap_clocks);
75 void __iomem *clk_memmaps[CLK_MAX_MEMMAPS];
76 
77 void omap2_clk_writel(u32 val, struct clk_hw_omap *clk, void __iomem *reg)
78 {
79 	if (clk->flags & MEMMAP_ADDRESSING) {
80 		struct clk_omap_reg *r = (struct clk_omap_reg *)&reg;
81 		writel_relaxed(val, clk_memmaps[r->index] + r->offset);
82 	} else {
83 		writel_relaxed(val, reg);
84 	}
85 }
86 
87 u32 omap2_clk_readl(struct clk_hw_omap *clk, void __iomem *reg)
88 {
89 	u32 val;
90 
91 	if (clk->flags & MEMMAP_ADDRESSING) {
92 		struct clk_omap_reg *r = (struct clk_omap_reg *)&reg;
93 		val = readl_relaxed(clk_memmaps[r->index] + r->offset);
94 	} else {
95 		val = readl_relaxed(reg);
96 	}
97 
98 	return val;
99 }
100 
101 /*
102  * OMAP2+ specific clock functions
103  */
104 
105 /* Private functions */
106 
107 
108 /**
109  * _wait_idlest_generic - wait for a module to leave the idle state
110  * @clk: module clock to wait for (needed for register offsets)
111  * @reg: virtual address of module IDLEST register
112  * @mask: value to mask against to determine if the module is active
113  * @idlest: idle state indicator (0 or 1) for the clock
114  * @name: name of the clock (for printk)
115  *
116  * Wait for a module to leave idle, where its idle-status register is
117  * not inside the CM module.  Returns 1 if the module left idle
118  * promptly, or 0 if the module did not leave idle before the timeout
119  * elapsed.  XXX Deprecated - should be moved into drivers for the
120  * individual IP block that the IDLEST register exists in.
121  */
122 static int _wait_idlest_generic(struct clk_hw_omap *clk, void __iomem *reg,
123 				u32 mask, u8 idlest, const char *name)
124 {
125 	int i = 0, ena = 0;
126 
127 	ena = (idlest) ? 0 : mask;
128 
129 	omap_test_timeout(((omap2_clk_readl(clk, reg) & mask) == ena),
130 			  MAX_MODULE_ENABLE_WAIT, i);
131 
132 	if (i < MAX_MODULE_ENABLE_WAIT)
133 		pr_debug("omap clock: module associated with clock %s ready after %d loops\n",
134 			 name, i);
135 	else
136 		pr_err("omap clock: module associated with clock %s didn't enable in %d tries\n",
137 		       name, MAX_MODULE_ENABLE_WAIT);
138 
139 	return (i < MAX_MODULE_ENABLE_WAIT) ? 1 : 0;
140 };
141 
142 /**
143  * _omap2_module_wait_ready - wait for an OMAP module to leave IDLE
144  * @clk: struct clk * belonging to the module
145  *
146  * If the necessary clocks for the OMAP hardware IP block that
147  * corresponds to clock @clk are enabled, then wait for the module to
148  * indicate readiness (i.e., to leave IDLE).  This code does not
149  * belong in the clock code and will be moved in the medium term to
150  * module-dependent code.  No return value.
151  */
152 static void _omap2_module_wait_ready(struct clk_hw_omap *clk)
153 {
154 	void __iomem *companion_reg, *idlest_reg;
155 	u8 other_bit, idlest_bit, idlest_val, idlest_reg_id;
156 	s16 prcm_mod;
157 	int r;
158 
159 	/* Not all modules have multiple clocks that their IDLEST depends on */
160 	if (clk->ops->find_companion) {
161 		clk->ops->find_companion(clk, &companion_reg, &other_bit);
162 		if (!(omap2_clk_readl(clk, companion_reg) & (1 << other_bit)))
163 			return;
164 	}
165 
166 	clk->ops->find_idlest(clk, &idlest_reg, &idlest_bit, &idlest_val);
167 	r = cm_split_idlest_reg(idlest_reg, &prcm_mod, &idlest_reg_id);
168 	if (r) {
169 		/* IDLEST register not in the CM module */
170 		_wait_idlest_generic(clk, idlest_reg, (1 << idlest_bit),
171 				     idlest_val, __clk_get_name(clk->hw.clk));
172 	} else {
173 		omap_cm_wait_module_ready(0, prcm_mod, idlest_reg_id,
174 					  idlest_bit);
175 	};
176 }
177 
178 /* Public functions */
179 
180 /**
181  * omap2_init_clk_clkdm - look up a clockdomain name, store pointer in clk
182  * @clk: OMAP clock struct ptr to use
183  *
184  * Convert a clockdomain name stored in a struct clk 'clk' into a
185  * clockdomain pointer, and save it into the struct clk.  Intended to be
186  * called during clk_register().  No return value.
187  */
188 void omap2_init_clk_clkdm(struct clk_hw *hw)
189 {
190 	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
191 	struct clockdomain *clkdm;
192 	const char *clk_name;
193 
194 	if (!clk->clkdm_name)
195 		return;
196 
197 	clk_name = __clk_get_name(hw->clk);
198 
199 	clkdm = clkdm_lookup(clk->clkdm_name);
200 	if (clkdm) {
201 		pr_debug("clock: associated clk %s to clkdm %s\n",
202 			 clk_name, clk->clkdm_name);
203 		clk->clkdm = clkdm;
204 	} else {
205 		pr_debug("clock: could not associate clk %s to clkdm %s\n",
206 			 clk_name, clk->clkdm_name);
207 	}
208 }
209 
210 /**
211  * omap2_clk_disable_clkdm_control - disable clkdm control on clk enable/disable
212  *
213  * Prevent the OMAP clock code from calling into the clockdomain code
214  * when a hardware clock in that clockdomain is enabled or disabled.
215  * Intended to be called at init time from omap*_clk_init().  No
216  * return value.
217  */
218 void __init omap2_clk_disable_clkdm_control(void)
219 {
220 	clkdm_control = false;
221 }
222 
223 /**
224  * omap2_clk_dflt_find_companion - find companion clock to @clk
225  * @clk: struct clk * to find the companion clock of
226  * @other_reg: void __iomem ** to return the companion clock CM_*CLKEN va in
227  * @other_bit: u8 ** to return the companion clock bit shift in
228  *
229  * Note: We don't need special code here for INVERT_ENABLE for the
230  * time being since INVERT_ENABLE only applies to clocks enabled by
231  * CM_CLKEN_PLL
232  *
233  * Convert CM_ICLKEN* <-> CM_FCLKEN*.  This conversion assumes it's
234  * just a matter of XORing the bits.
235  *
236  * Some clocks don't have companion clocks.  For example, modules with
237  * only an interface clock (such as MAILBOXES) don't have a companion
238  * clock.  Right now, this code relies on the hardware exporting a bit
239  * in the correct companion register that indicates that the
240  * nonexistent 'companion clock' is active.  Future patches will
241  * associate this type of code with per-module data structures to
242  * avoid this issue, and remove the casts.  No return value.
243  */
244 void omap2_clk_dflt_find_companion(struct clk_hw_omap *clk,
245 			void __iomem **other_reg, u8 *other_bit)
246 {
247 	u32 r;
248 
249 	/*
250 	 * Convert CM_ICLKEN* <-> CM_FCLKEN*.  This conversion assumes
251 	 * it's just a matter of XORing the bits.
252 	 */
253 	r = ((__force u32)clk->enable_reg ^ (CM_FCLKEN ^ CM_ICLKEN));
254 
255 	*other_reg = (__force void __iomem *)r;
256 	*other_bit = clk->enable_bit;
257 }
258 
259 /**
260  * omap2_clk_dflt_find_idlest - find CM_IDLEST reg va, bit shift for @clk
261  * @clk: struct clk * to find IDLEST info for
262  * @idlest_reg: void __iomem ** to return the CM_IDLEST va in
263  * @idlest_bit: u8 * to return the CM_IDLEST bit shift in
264  * @idlest_val: u8 * to return the idle status indicator
265  *
266  * Return the CM_IDLEST register address and bit shift corresponding
267  * to the module that "owns" this clock.  This default code assumes
268  * that the CM_IDLEST bit shift is the CM_*CLKEN bit shift, and that
269  * the IDLEST register address ID corresponds to the CM_*CLKEN
270  * register address ID (e.g., that CM_FCLKEN2 corresponds to
271  * CM_IDLEST2).  This is not true for all modules.  No return value.
272  */
273 void omap2_clk_dflt_find_idlest(struct clk_hw_omap *clk,
274 		void __iomem **idlest_reg, u8 *idlest_bit, u8 *idlest_val)
275 {
276 	u32 r;
277 
278 	r = (((__force u32)clk->enable_reg & ~0xf0) | 0x20);
279 	*idlest_reg = (__force void __iomem *)r;
280 	*idlest_bit = clk->enable_bit;
281 
282 	/*
283 	 * 24xx uses 0 to indicate not ready, and 1 to indicate ready.
284 	 * 34xx reverses this, just to keep us on our toes
285 	 * AM35xx uses both, depending on the module.
286 	 */
287 	*idlest_val = ti_clk_features.cm_idlest_val;
288 }
289 
290 /**
291  * omap2_dflt_clk_enable - enable a clock in the hardware
292  * @hw: struct clk_hw * of the clock to enable
293  *
294  * Enable the clock @hw in the hardware.  We first call into the OMAP
295  * clockdomain code to "enable" the corresponding clockdomain if this
296  * is the first enabled user of the clockdomain.  Then program the
297  * hardware to enable the clock.  Then wait for the IP block that uses
298  * this clock to leave idle (if applicable).  Returns the error value
299  * from clkdm_clk_enable() if it terminated with an error, or -EINVAL
300  * if @hw has a null clock enable_reg, or zero upon success.
301  */
302 int omap2_dflt_clk_enable(struct clk_hw *hw)
303 {
304 	struct clk_hw_omap *clk;
305 	u32 v;
306 	int ret = 0;
307 
308 	clk = to_clk_hw_omap(hw);
309 
310 	if (clkdm_control && clk->clkdm) {
311 		ret = clkdm_clk_enable(clk->clkdm, hw->clk);
312 		if (ret) {
313 			WARN(1, "%s: could not enable %s's clockdomain %s: %d\n",
314 			     __func__, __clk_get_name(hw->clk),
315 			     clk->clkdm->name, ret);
316 			return ret;
317 		}
318 	}
319 
320 	if (unlikely(clk->enable_reg == NULL)) {
321 		pr_err("%s: %s missing enable_reg\n", __func__,
322 		       __clk_get_name(hw->clk));
323 		ret = -EINVAL;
324 		goto err;
325 	}
326 
327 	/* FIXME should not have INVERT_ENABLE bit here */
328 	v = omap2_clk_readl(clk, clk->enable_reg);
329 	if (clk->flags & INVERT_ENABLE)
330 		v &= ~(1 << clk->enable_bit);
331 	else
332 		v |= (1 << clk->enable_bit);
333 	omap2_clk_writel(v, clk, clk->enable_reg);
334 	v = omap2_clk_readl(clk, clk->enable_reg); /* OCP barrier */
335 
336 	if (clk->ops && clk->ops->find_idlest)
337 		_omap2_module_wait_ready(clk);
338 
339 	return 0;
340 
341 err:
342 	if (clkdm_control && clk->clkdm)
343 		clkdm_clk_disable(clk->clkdm, hw->clk);
344 	return ret;
345 }
346 
347 /**
348  * omap2_dflt_clk_disable - disable a clock in the hardware
349  * @hw: struct clk_hw * of the clock to disable
350  *
351  * Disable the clock @hw in the hardware, and call into the OMAP
352  * clockdomain code to "disable" the corresponding clockdomain if all
353  * clocks/hwmods in that clockdomain are now disabled.  No return
354  * value.
355  */
356 void omap2_dflt_clk_disable(struct clk_hw *hw)
357 {
358 	struct clk_hw_omap *clk;
359 	u32 v;
360 
361 	clk = to_clk_hw_omap(hw);
362 	if (!clk->enable_reg) {
363 		/*
364 		 * 'independent' here refers to a clock which is not
365 		 * controlled by its parent.
366 		 */
367 		pr_err("%s: independent clock %s has no enable_reg\n",
368 		       __func__, __clk_get_name(hw->clk));
369 		return;
370 	}
371 
372 	v = omap2_clk_readl(clk, clk->enable_reg);
373 	if (clk->flags & INVERT_ENABLE)
374 		v |= (1 << clk->enable_bit);
375 	else
376 		v &= ~(1 << clk->enable_bit);
377 	omap2_clk_writel(v, clk, clk->enable_reg);
378 	/* No OCP barrier needed here since it is a disable operation */
379 
380 	if (clkdm_control && clk->clkdm)
381 		clkdm_clk_disable(clk->clkdm, hw->clk);
382 }
383 
384 /**
385  * omap2_clkops_enable_clkdm - increment usecount on clkdm of @hw
386  * @hw: struct clk_hw * of the clock being enabled
387  *
388  * Increment the usecount of the clockdomain of the clock pointed to
389  * by @hw; if the usecount is 1, the clockdomain will be "enabled."
390  * Only needed for clocks that don't use omap2_dflt_clk_enable() as
391  * their enable function pointer.  Passes along the return value of
392  * clkdm_clk_enable(), -EINVAL if @hw is not associated with a
393  * clockdomain, or 0 if clock framework-based clockdomain control is
394  * not implemented.
395  */
396 int omap2_clkops_enable_clkdm(struct clk_hw *hw)
397 {
398 	struct clk_hw_omap *clk;
399 	int ret = 0;
400 
401 	clk = to_clk_hw_omap(hw);
402 
403 	if (unlikely(!clk->clkdm)) {
404 		pr_err("%s: %s: no clkdm set ?!\n", __func__,
405 		       __clk_get_name(hw->clk));
406 		return -EINVAL;
407 	}
408 
409 	if (unlikely(clk->enable_reg))
410 		pr_err("%s: %s: should use dflt_clk_enable ?!\n", __func__,
411 		       __clk_get_name(hw->clk));
412 
413 	if (!clkdm_control) {
414 		pr_err("%s: %s: clkfw-based clockdomain control disabled ?!\n",
415 		       __func__, __clk_get_name(hw->clk));
416 		return 0;
417 	}
418 
419 	ret = clkdm_clk_enable(clk->clkdm, hw->clk);
420 	WARN(ret, "%s: could not enable %s's clockdomain %s: %d\n",
421 	     __func__, __clk_get_name(hw->clk), clk->clkdm->name, ret);
422 
423 	return ret;
424 }
425 
426 /**
427  * omap2_clkops_disable_clkdm - decrement usecount on clkdm of @hw
428  * @hw: struct clk_hw * of the clock being disabled
429  *
430  * Decrement the usecount of the clockdomain of the clock pointed to
431  * by @hw; if the usecount is 0, the clockdomain will be "disabled."
432  * Only needed for clocks that don't use omap2_dflt_clk_disable() as their
433  * disable function pointer.  No return value.
434  */
435 void omap2_clkops_disable_clkdm(struct clk_hw *hw)
436 {
437 	struct clk_hw_omap *clk;
438 
439 	clk = to_clk_hw_omap(hw);
440 
441 	if (unlikely(!clk->clkdm)) {
442 		pr_err("%s: %s: no clkdm set ?!\n", __func__,
443 		       __clk_get_name(hw->clk));
444 		return;
445 	}
446 
447 	if (unlikely(clk->enable_reg))
448 		pr_err("%s: %s: should use dflt_clk_disable ?!\n", __func__,
449 		       __clk_get_name(hw->clk));
450 
451 	if (!clkdm_control) {
452 		pr_err("%s: %s: clkfw-based clockdomain control disabled ?!\n",
453 		       __func__, __clk_get_name(hw->clk));
454 		return;
455 	}
456 
457 	clkdm_clk_disable(clk->clkdm, hw->clk);
458 }
459 
460 /**
461  * omap2_dflt_clk_is_enabled - is clock enabled in the hardware?
462  * @hw: struct clk_hw * to check
463  *
464  * Return 1 if the clock represented by @hw is enabled in the
465  * hardware, or 0 otherwise.  Intended for use in the struct
466  * clk_ops.is_enabled function pointer.
467  */
468 int omap2_dflt_clk_is_enabled(struct clk_hw *hw)
469 {
470 	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
471 	u32 v;
472 
473 	v = omap2_clk_readl(clk, clk->enable_reg);
474 
475 	if (clk->flags & INVERT_ENABLE)
476 		v ^= BIT(clk->enable_bit);
477 
478 	v &= BIT(clk->enable_bit);
479 
480 	return v ? 1 : 0;
481 }
482 
483 static int __initdata mpurate;
484 
485 /*
486  * By default we use the rate set by the bootloader.
487  * You can override this with mpurate= cmdline option.
488  */
489 static int __init omap_clk_setup(char *str)
490 {
491 	get_option(&str, &mpurate);
492 
493 	if (!mpurate)
494 		return 1;
495 
496 	if (mpurate < 1000)
497 		mpurate *= 1000000;
498 
499 	return 1;
500 }
501 __setup("mpurate=", omap_clk_setup);
502 
503 /**
504  * omap2_init_clk_hw_omap_clocks - initialize an OMAP clock
505  * @clk: struct clk * to initialize
506  *
507  * Add an OMAP clock @clk to the internal list of OMAP clocks.  Used
508  * temporarily for autoidle handling, until this support can be
509  * integrated into the common clock framework code in some way.  No
510  * return value.
511  */
512 void omap2_init_clk_hw_omap_clocks(struct clk *clk)
513 {
514 	struct clk_hw_omap *c;
515 
516 	if (__clk_get_flags(clk) & CLK_IS_BASIC)
517 		return;
518 
519 	c = to_clk_hw_omap(__clk_get_hw(clk));
520 	list_add(&c->node, &clk_hw_omap_clocks);
521 }
522 
523 /**
524  * omap2_clk_enable_autoidle_all - enable autoidle on all OMAP clocks that
525  * support it
526  *
527  * Enable clock autoidle on all OMAP clocks that have allow_idle
528  * function pointers associated with them.  This function is intended
529  * to be temporary until support for this is added to the common clock
530  * code.  Returns 0.
531  */
532 int omap2_clk_enable_autoidle_all(void)
533 {
534 	struct clk_hw_omap *c;
535 
536 	list_for_each_entry(c, &clk_hw_omap_clocks, node)
537 		if (c->ops && c->ops->allow_idle)
538 			c->ops->allow_idle(c);
539 
540 	of_ti_clk_allow_autoidle_all();
541 
542 	return 0;
543 }
544 
545 /**
546  * omap2_clk_disable_autoidle_all - disable autoidle on all OMAP clocks that
547  * support it
548  *
549  * Disable clock autoidle on all OMAP clocks that have allow_idle
550  * function pointers associated with them.  This function is intended
551  * to be temporary until support for this is added to the common clock
552  * code.  Returns 0.
553  */
554 int omap2_clk_disable_autoidle_all(void)
555 {
556 	struct clk_hw_omap *c;
557 
558 	list_for_each_entry(c, &clk_hw_omap_clocks, node)
559 		if (c->ops && c->ops->deny_idle)
560 			c->ops->deny_idle(c);
561 
562 	of_ti_clk_deny_autoidle_all();
563 
564 	return 0;
565 }
566 
567 /**
568  * omap2_clk_deny_idle - disable autoidle on an OMAP clock
569  * @clk: struct clk * to disable autoidle for
570  *
571  * Disable autoidle on an OMAP clock.
572  */
573 int omap2_clk_deny_idle(struct clk *clk)
574 {
575 	struct clk_hw_omap *c;
576 
577 	if (__clk_get_flags(clk) & CLK_IS_BASIC)
578 		return -EINVAL;
579 
580 	c = to_clk_hw_omap(__clk_get_hw(clk));
581 	if (c->ops && c->ops->deny_idle)
582 		c->ops->deny_idle(c);
583 	return 0;
584 }
585 
586 /**
587  * omap2_clk_allow_idle - enable autoidle on an OMAP clock
588  * @clk: struct clk * to enable autoidle for
589  *
590  * Enable autoidle on an OMAP clock.
591  */
592 int omap2_clk_allow_idle(struct clk *clk)
593 {
594 	struct clk_hw_omap *c;
595 
596 	if (__clk_get_flags(clk) & CLK_IS_BASIC)
597 		return -EINVAL;
598 
599 	c = to_clk_hw_omap(__clk_get_hw(clk));
600 	if (c->ops && c->ops->allow_idle)
601 		c->ops->allow_idle(c);
602 	return 0;
603 }
604 
605 /**
606  * omap2_clk_enable_init_clocks - prepare & enable a list of clocks
607  * @clk_names: ptr to an array of strings of clock names to enable
608  * @num_clocks: number of clock names in @clk_names
609  *
610  * Prepare and enable a list of clocks, named by @clk_names.  No
611  * return value. XXX Deprecated; only needed until these clocks are
612  * properly claimed and enabled by the drivers or core code that uses
613  * them.  XXX What code disables & calls clk_put on these clocks?
614  */
615 void omap2_clk_enable_init_clocks(const char **clk_names, u8 num_clocks)
616 {
617 	struct clk *init_clk;
618 	int i;
619 
620 	for (i = 0; i < num_clocks; i++) {
621 		init_clk = clk_get(NULL, clk_names[i]);
622 		clk_prepare_enable(init_clk);
623 	}
624 }
625 
626 const struct clk_hw_omap_ops clkhwops_wait = {
627 	.find_idlest	= omap2_clk_dflt_find_idlest,
628 	.find_companion	= omap2_clk_dflt_find_companion,
629 };
630 
631 /**
632  * omap2_clk_switch_mpurate_at_boot - switch ARM MPU rate by boot-time argument
633  * @mpurate_ck_name: clk name of the clock to change rate
634  *
635  * Change the ARM MPU clock rate to the rate specified on the command
636  * line, if one was specified.  @mpurate_ck_name should be
637  * "virt_prcm_set" on OMAP2xxx and "dpll1_ck" on OMAP34xx/OMAP36xx.
638  * XXX Does not handle voltage scaling - on OMAP2xxx this is currently
639  * handled by the virt_prcm_set clock, but this should be handled by
640  * the OPP layer.  XXX This is intended to be handled by the OPP layer
641  * code in the near future and should be removed from the clock code.
642  * Returns -EINVAL if 'mpurate' is zero or if clk_set_rate() rejects
643  * the rate, -ENOENT if the struct clk referred to by @mpurate_ck_name
644  * cannot be found, or 0 upon success.
645  */
646 int __init omap2_clk_switch_mpurate_at_boot(const char *mpurate_ck_name)
647 {
648 	struct clk *mpurate_ck;
649 	int r;
650 
651 	if (!mpurate)
652 		return -EINVAL;
653 
654 	mpurate_ck = clk_get(NULL, mpurate_ck_name);
655 	if (WARN(IS_ERR(mpurate_ck), "Failed to get %s.\n", mpurate_ck_name))
656 		return -ENOENT;
657 
658 	r = clk_set_rate(mpurate_ck, mpurate);
659 	if (r < 0) {
660 		WARN(1, "clock: %s: unable to set MPU rate to %d: %d\n",
661 		     mpurate_ck_name, mpurate, r);
662 		clk_put(mpurate_ck);
663 		return -EINVAL;
664 	}
665 
666 	calibrate_delay();
667 	clk_put(mpurate_ck);
668 
669 	return 0;
670 }
671 
672 /**
673  * omap2_clk_print_new_rates - print summary of current clock tree rates
674  * @hfclkin_ck_name: clk name for the off-chip HF oscillator
675  * @core_ck_name: clk name for the on-chip CORE_CLK
676  * @mpu_ck_name: clk name for the ARM MPU clock
677  *
678  * Prints a short message to the console with the HFCLKIN oscillator
679  * rate, the rate of the CORE clock, and the rate of the ARM MPU clock.
680  * Called by the boot-time MPU rate switching code.   XXX This is intended
681  * to be handled by the OPP layer code in the near future and should be
682  * removed from the clock code.  No return value.
683  */
684 void __init omap2_clk_print_new_rates(const char *hfclkin_ck_name,
685 				      const char *core_ck_name,
686 				      const char *mpu_ck_name)
687 {
688 	struct clk *hfclkin_ck, *core_ck, *mpu_ck;
689 	unsigned long hfclkin_rate;
690 
691 	mpu_ck = clk_get(NULL, mpu_ck_name);
692 	if (WARN(IS_ERR(mpu_ck), "clock: failed to get %s.\n", mpu_ck_name))
693 		return;
694 
695 	core_ck = clk_get(NULL, core_ck_name);
696 	if (WARN(IS_ERR(core_ck), "clock: failed to get %s.\n", core_ck_name))
697 		return;
698 
699 	hfclkin_ck = clk_get(NULL, hfclkin_ck_name);
700 	if (WARN(IS_ERR(hfclkin_ck), "Failed to get %s.\n", hfclkin_ck_name))
701 		return;
702 
703 	hfclkin_rate = clk_get_rate(hfclkin_ck);
704 
705 	pr_info("Switched to new clocking rate (Crystal/Core/MPU): %ld.%01ld/%ld/%ld MHz\n",
706 		(hfclkin_rate / 1000000), ((hfclkin_rate / 100000) % 10),
707 		(clk_get_rate(core_ck) / 1000000),
708 		(clk_get_rate(mpu_ck) / 1000000));
709 }
710 
711 /**
712  * ti_clk_init_features - init clock features struct for the SoC
713  *
714  * Initializes the clock features struct based on the SoC type.
715  */
716 void __init ti_clk_init_features(void)
717 {
718 	/* Fint setup for DPLLs */
719 	if (cpu_is_omap3430()) {
720 		ti_clk_features.fint_min = OMAP3430_DPLL_FINT_BAND1_MIN;
721 		ti_clk_features.fint_max = OMAP3430_DPLL_FINT_BAND2_MAX;
722 		ti_clk_features.fint_band1_max = OMAP3430_DPLL_FINT_BAND1_MAX;
723 		ti_clk_features.fint_band2_min = OMAP3430_DPLL_FINT_BAND2_MIN;
724 	} else {
725 		ti_clk_features.fint_min = OMAP3PLUS_DPLL_FINT_MIN;
726 		ti_clk_features.fint_max = OMAP3PLUS_DPLL_FINT_MAX;
727 	}
728 
729 	/* Bypass value setup for DPLLs */
730 	if (cpu_is_omap24xx()) {
731 		ti_clk_features.dpll_bypass_vals |=
732 			(1 << OMAP2XXX_EN_DPLL_LPBYPASS) |
733 			(1 << OMAP2XXX_EN_DPLL_FRBYPASS);
734 	} else if (cpu_is_omap34xx()) {
735 		ti_clk_features.dpll_bypass_vals |=
736 			(1 << OMAP3XXX_EN_DPLL_LPBYPASS) |
737 			(1 << OMAP3XXX_EN_DPLL_FRBYPASS);
738 	} else if (soc_is_am33xx() || cpu_is_omap44xx() || soc_is_am43xx() ||
739 		   soc_is_omap54xx() || soc_is_dra7xx()) {
740 		ti_clk_features.dpll_bypass_vals |=
741 			(1 << OMAP4XXX_EN_DPLL_LPBYPASS) |
742 			(1 << OMAP4XXX_EN_DPLL_FRBYPASS) |
743 			(1 << OMAP4XXX_EN_DPLL_MNBYPASS);
744 	}
745 
746 	/* Jitter correction only available on OMAP343X */
747 	if (cpu_is_omap343x())
748 		ti_clk_features.flags |= TI_CLK_DPLL_HAS_FREQSEL;
749 
750 	/* Idlest value for interface clocks.
751 	 * 24xx uses 0 to indicate not ready, and 1 to indicate ready.
752 	 * 34xx reverses this, just to keep us on our toes
753 	 * AM35xx uses both, depending on the module.
754 	 */
755 	if (cpu_is_omap24xx())
756 		ti_clk_features.cm_idlest_val = OMAP24XX_CM_IDLEST_VAL;
757 	else if (cpu_is_omap34xx())
758 		ti_clk_features.cm_idlest_val = OMAP34XX_CM_IDLEST_VAL;
759 
760 	/* On OMAP3430 ES1.0, DPLL4 can't be re-programmed */
761 	if (omap_rev() == OMAP3430_REV_ES1_0)
762 		ti_clk_features.flags |= TI_CLK_DPLL4_DENY_REPROGRAM;
763 }
764