xref: /linux/arch/arm/mach-omap2/cminst44xx.c (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
1 /*
2  * OMAP4 CM instance functions
3  *
4  * Copyright (C) 2009 Nokia Corporation
5  * Copyright (C) 2008-2011 Texas Instruments, Inc.
6  * Paul Walmsley
7  * Rajendra Nayak <rnayak@ti.com>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  *
13  * This is needed since CM instances can be in the PRM, PRCM_MPU, CM1,
14  * or CM2 hardware modules.  For example, the EMU_CM CM instance is in
15  * the PRM hardware module.  What a mess...
16  */
17 
18 #include <linux/kernel.h>
19 #include <linux/types.h>
20 #include <linux/errno.h>
21 #include <linux/err.h>
22 #include <linux/io.h>
23 
24 #include "clockdomain.h"
25 #include "cm.h"
26 #include "cm1_44xx.h"
27 #include "cm2_44xx.h"
28 #include "cm44xx.h"
29 #include "cm-regbits-34xx.h"
30 #include "prcm44xx.h"
31 #include "prm44xx.h"
32 #include "prcm_mpu44xx.h"
33 #include "prcm-common.h"
34 
35 #define OMAP4430_IDLEST_SHIFT		16
36 #define OMAP4430_IDLEST_MASK		(0x3 << 16)
37 #define OMAP4430_CLKTRCTRL_SHIFT	0
38 #define OMAP4430_CLKTRCTRL_MASK		(0x3 << 0)
39 #define OMAP4430_MODULEMODE_SHIFT	0
40 #define OMAP4430_MODULEMODE_MASK	(0x3 << 0)
41 
42 /*
43  * CLKCTRL_IDLEST_*: possible values for the CM_*_CLKCTRL.IDLEST bitfield:
44  *
45  *   0x0 func:     Module is fully functional, including OCP
46  *   0x1 trans:    Module is performing transition: wakeup, or sleep, or sleep
47  *                 abortion
48  *   0x2 idle:     Module is in Idle mode (only OCP part). It is functional if
49  *                 using separate functional clock
50  *   0x3 disabled: Module is disabled and cannot be accessed
51  *
52  */
53 #define CLKCTRL_IDLEST_FUNCTIONAL		0x0
54 #define CLKCTRL_IDLEST_INTRANSITION		0x1
55 #define CLKCTRL_IDLEST_INTERFACE_IDLE		0x2
56 #define CLKCTRL_IDLEST_DISABLED			0x3
57 
58 static void __iomem *_cm_bases[OMAP4_MAX_PRCM_PARTITIONS];
59 
60 /**
61  * omap_cm_base_init - Populates the cm partitions
62  *
63  * Populates the base addresses of the _cm_bases
64  * array used for read/write of cm module registers.
65  */
66 void omap_cm_base_init(void)
67 {
68 	_cm_bases[OMAP4430_PRM_PARTITION] = prm_base;
69 	_cm_bases[OMAP4430_CM1_PARTITION] = cm_base;
70 	_cm_bases[OMAP4430_CM2_PARTITION] = cm2_base;
71 	_cm_bases[OMAP4430_PRCM_MPU_PARTITION] = prcm_mpu_base;
72 }
73 
74 /* Private functions */
75 
76 static u32 omap4_cminst_read_inst_reg(u8 part, u16 inst, u16 idx);
77 
78 /**
79  * _clkctrl_idlest - read a CM_*_CLKCTRL register; mask & shift IDLEST bitfield
80  * @part: PRCM partition ID that the CM_CLKCTRL register exists in
81  * @inst: CM instance register offset (*_INST macro)
82  * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro)
83  *
84  * Return the IDLEST bitfield of a CM_*_CLKCTRL register, shifted down to
85  * bit 0.
86  */
87 static u32 _clkctrl_idlest(u8 part, u16 inst, u16 clkctrl_offs)
88 {
89 	u32 v = omap4_cminst_read_inst_reg(part, inst, clkctrl_offs);
90 	v &= OMAP4430_IDLEST_MASK;
91 	v >>= OMAP4430_IDLEST_SHIFT;
92 	return v;
93 }
94 
95 /**
96  * _is_module_ready - can module registers be accessed without causing an abort?
97  * @part: PRCM partition ID that the CM_CLKCTRL register exists in
98  * @inst: CM instance register offset (*_INST macro)
99  * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro)
100  *
101  * Returns true if the module's CM_*_CLKCTRL.IDLEST bitfield is either
102  * *FUNCTIONAL or *INTERFACE_IDLE; false otherwise.
103  */
104 static bool _is_module_ready(u8 part, u16 inst, u16 clkctrl_offs)
105 {
106 	u32 v;
107 
108 	v = _clkctrl_idlest(part, inst, clkctrl_offs);
109 
110 	return (v == CLKCTRL_IDLEST_FUNCTIONAL ||
111 		v == CLKCTRL_IDLEST_INTERFACE_IDLE) ? true : false;
112 }
113 
114 /* Read a register in a CM instance */
115 static u32 omap4_cminst_read_inst_reg(u8 part, u16 inst, u16 idx)
116 {
117 	BUG_ON(part >= OMAP4_MAX_PRCM_PARTITIONS ||
118 	       part == OMAP4430_INVALID_PRCM_PARTITION ||
119 	       !_cm_bases[part]);
120 	return readl_relaxed(_cm_bases[part] + inst + idx);
121 }
122 
123 /* Write into a register in a CM instance */
124 static void omap4_cminst_write_inst_reg(u32 val, u8 part, u16 inst, u16 idx)
125 {
126 	BUG_ON(part >= OMAP4_MAX_PRCM_PARTITIONS ||
127 	       part == OMAP4430_INVALID_PRCM_PARTITION ||
128 	       !_cm_bases[part]);
129 	writel_relaxed(val, _cm_bases[part] + inst + idx);
130 }
131 
132 /* Read-modify-write a register in CM1. Caller must lock */
133 static u32 omap4_cminst_rmw_inst_reg_bits(u32 mask, u32 bits, u8 part, u16 inst,
134 					  s16 idx)
135 {
136 	u32 v;
137 
138 	v = omap4_cminst_read_inst_reg(part, inst, idx);
139 	v &= ~mask;
140 	v |= bits;
141 	omap4_cminst_write_inst_reg(v, part, inst, idx);
142 
143 	return v;
144 }
145 
146 static u32 omap4_cminst_set_inst_reg_bits(u32 bits, u8 part, u16 inst, s16 idx)
147 {
148 	return omap4_cminst_rmw_inst_reg_bits(bits, bits, part, inst, idx);
149 }
150 
151 static u32 omap4_cminst_clear_inst_reg_bits(u32 bits, u8 part, u16 inst,
152 					    s16 idx)
153 {
154 	return omap4_cminst_rmw_inst_reg_bits(bits, 0x0, part, inst, idx);
155 }
156 
157 static u32 omap4_cminst_read_inst_reg_bits(u8 part, u16 inst, s16 idx, u32 mask)
158 {
159 	u32 v;
160 
161 	v = omap4_cminst_read_inst_reg(part, inst, idx);
162 	v &= mask;
163 	v >>= __ffs(mask);
164 
165 	return v;
166 }
167 
168 /*
169  *
170  */
171 
172 /**
173  * _clktrctrl_write - write @c to a CM_CLKSTCTRL.CLKTRCTRL register bitfield
174  * @c: CLKTRCTRL register bitfield (LSB = bit 0, i.e., unshifted)
175  * @part: PRCM partition ID that the CM_CLKSTCTRL register exists in
176  * @inst: CM instance register offset (*_INST macro)
177  * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
178  *
179  * @c must be the unshifted value for CLKTRCTRL - i.e., this function
180  * will handle the shift itself.
181  */
182 static void _clktrctrl_write(u8 c, u8 part, u16 inst, u16 cdoffs)
183 {
184 	u32 v;
185 
186 	v = omap4_cminst_read_inst_reg(part, inst, cdoffs + OMAP4_CM_CLKSTCTRL);
187 	v &= ~OMAP4430_CLKTRCTRL_MASK;
188 	v |= c << OMAP4430_CLKTRCTRL_SHIFT;
189 	omap4_cminst_write_inst_reg(v, part, inst, cdoffs + OMAP4_CM_CLKSTCTRL);
190 }
191 
192 /**
193  * omap4_cminst_is_clkdm_in_hwsup - is a clockdomain in hwsup idle mode?
194  * @part: PRCM partition ID that the CM_CLKSTCTRL register exists in
195  * @inst: CM instance register offset (*_INST macro)
196  * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
197  *
198  * Returns true if the clockdomain referred to by (@part, @inst, @cdoffs)
199  * is in hardware-supervised idle mode, or 0 otherwise.
200  */
201 static bool omap4_cminst_is_clkdm_in_hwsup(u8 part, u16 inst, u16 cdoffs)
202 {
203 	u32 v;
204 
205 	v = omap4_cminst_read_inst_reg(part, inst, cdoffs + OMAP4_CM_CLKSTCTRL);
206 	v &= OMAP4430_CLKTRCTRL_MASK;
207 	v >>= OMAP4430_CLKTRCTRL_SHIFT;
208 
209 	return (v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) ? true : false;
210 }
211 
212 /**
213  * omap4_cminst_clkdm_enable_hwsup - put a clockdomain in hwsup-idle mode
214  * @part: PRCM partition ID that the clockdomain registers exist in
215  * @inst: CM instance register offset (*_INST macro)
216  * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
217  *
218  * Put a clockdomain referred to by (@part, @inst, @cdoffs) into
219  * hardware-supervised idle mode.  No return value.
220  */
221 static void omap4_cminst_clkdm_enable_hwsup(u8 part, u16 inst, u16 cdoffs)
222 {
223 	_clktrctrl_write(OMAP34XX_CLKSTCTRL_ENABLE_AUTO, part, inst, cdoffs);
224 }
225 
226 /**
227  * omap4_cminst_clkdm_disable_hwsup - put a clockdomain in swsup-idle mode
228  * @part: PRCM partition ID that the clockdomain registers exist in
229  * @inst: CM instance register offset (*_INST macro)
230  * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
231  *
232  * Put a clockdomain referred to by (@part, @inst, @cdoffs) into
233  * software-supervised idle mode, i.e., controlled manually by the
234  * Linux OMAP clockdomain code.  No return value.
235  */
236 static void omap4_cminst_clkdm_disable_hwsup(u8 part, u16 inst, u16 cdoffs)
237 {
238 	_clktrctrl_write(OMAP34XX_CLKSTCTRL_DISABLE_AUTO, part, inst, cdoffs);
239 }
240 
241 /**
242  * omap4_cminst_clkdm_force_sleep - try to take a clockdomain out of idle
243  * @part: PRCM partition ID that the clockdomain registers exist in
244  * @inst: CM instance register offset (*_INST macro)
245  * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
246  *
247  * Take a clockdomain referred to by (@part, @inst, @cdoffs) out of idle,
248  * waking it up.  No return value.
249  */
250 static void omap4_cminst_clkdm_force_wakeup(u8 part, u16 inst, u16 cdoffs)
251 {
252 	_clktrctrl_write(OMAP34XX_CLKSTCTRL_FORCE_WAKEUP, part, inst, cdoffs);
253 }
254 
255 /*
256  *
257  */
258 
259 static void omap4_cminst_clkdm_force_sleep(u8 part, u16 inst, u16 cdoffs)
260 {
261 	_clktrctrl_write(OMAP34XX_CLKSTCTRL_FORCE_SLEEP, part, inst, cdoffs);
262 }
263 
264 /**
265  * omap4_cminst_wait_module_ready - wait for a module to be in 'func' state
266  * @part: PRCM partition ID that the CM_CLKCTRL register exists in
267  * @inst: CM instance register offset (*_INST macro)
268  * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro)
269  * @bit_shift: bit shift for the register, ignored for OMAP4+
270  *
271  * Wait for the module IDLEST to be functional. If the idle state is in any
272  * the non functional state (trans, idle or disabled), module and thus the
273  * sysconfig cannot be accessed and will probably lead to an "imprecise
274  * external abort"
275  */
276 static int omap4_cminst_wait_module_ready(u8 part, s16 inst, u16 clkctrl_offs,
277 					  u8 bit_shift)
278 {
279 	int i = 0;
280 
281 	if (!clkctrl_offs)
282 		return 0;
283 
284 	omap_test_timeout(_is_module_ready(part, inst, clkctrl_offs),
285 			  MAX_MODULE_READY_TIME, i);
286 
287 	return (i < MAX_MODULE_READY_TIME) ? 0 : -EBUSY;
288 }
289 
290 /**
291  * omap4_cminst_wait_module_idle - wait for a module to be in 'disabled'
292  * state
293  * @part: PRCM partition ID that the CM_CLKCTRL register exists in
294  * @inst: CM instance register offset (*_INST macro)
295  * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro)
296  * @bit_shift: Bit shift for the register, ignored for OMAP4+
297  *
298  * Wait for the module IDLEST to be disabled. Some PRCM transition,
299  * like reset assertion or parent clock de-activation must wait the
300  * module to be fully disabled.
301  */
302 static int omap4_cminst_wait_module_idle(u8 part, s16 inst, u16 clkctrl_offs,
303 					 u8 bit_shift)
304 {
305 	int i = 0;
306 
307 	if (!clkctrl_offs)
308 		return 0;
309 
310 	omap_test_timeout((_clkctrl_idlest(part, inst, clkctrl_offs) ==
311 			   CLKCTRL_IDLEST_DISABLED),
312 			  MAX_MODULE_DISABLE_TIME, i);
313 
314 	return (i < MAX_MODULE_DISABLE_TIME) ? 0 : -EBUSY;
315 }
316 
317 /**
318  * omap4_cminst_module_enable - Enable the modulemode inside CLKCTRL
319  * @mode: Module mode (SW or HW)
320  * @part: PRCM partition ID that the CM_CLKCTRL register exists in
321  * @inst: CM instance register offset (*_INST macro)
322  * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro)
323  *
324  * No return value.
325  */
326 static void omap4_cminst_module_enable(u8 mode, u8 part, u16 inst,
327 				       u16 clkctrl_offs)
328 {
329 	u32 v;
330 
331 	v = omap4_cminst_read_inst_reg(part, inst, clkctrl_offs);
332 	v &= ~OMAP4430_MODULEMODE_MASK;
333 	v |= mode << OMAP4430_MODULEMODE_SHIFT;
334 	omap4_cminst_write_inst_reg(v, part, inst, clkctrl_offs);
335 }
336 
337 /**
338  * omap4_cminst_module_disable - Disable the module inside CLKCTRL
339  * @part: PRCM partition ID that the CM_CLKCTRL register exists in
340  * @inst: CM instance register offset (*_INST macro)
341  * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro)
342  *
343  * No return value.
344  */
345 static void omap4_cminst_module_disable(u8 part, u16 inst, u16 clkctrl_offs)
346 {
347 	u32 v;
348 
349 	v = omap4_cminst_read_inst_reg(part, inst, clkctrl_offs);
350 	v &= ~OMAP4430_MODULEMODE_MASK;
351 	omap4_cminst_write_inst_reg(v, part, inst, clkctrl_offs);
352 }
353 
354 /*
355  * Clockdomain low-level functions
356  */
357 
358 static int omap4_clkdm_add_wkup_sleep_dep(struct clockdomain *clkdm1,
359 					struct clockdomain *clkdm2)
360 {
361 	omap4_cminst_set_inst_reg_bits((1 << clkdm2->dep_bit),
362 				       clkdm1->prcm_partition,
363 				       clkdm1->cm_inst, clkdm1->clkdm_offs +
364 				       OMAP4_CM_STATICDEP);
365 	return 0;
366 }
367 
368 static int omap4_clkdm_del_wkup_sleep_dep(struct clockdomain *clkdm1,
369 					struct clockdomain *clkdm2)
370 {
371 	omap4_cminst_clear_inst_reg_bits((1 << clkdm2->dep_bit),
372 					 clkdm1->prcm_partition,
373 					 clkdm1->cm_inst, clkdm1->clkdm_offs +
374 					 OMAP4_CM_STATICDEP);
375 	return 0;
376 }
377 
378 static int omap4_clkdm_read_wkup_sleep_dep(struct clockdomain *clkdm1,
379 					struct clockdomain *clkdm2)
380 {
381 	return omap4_cminst_read_inst_reg_bits(clkdm1->prcm_partition,
382 					       clkdm1->cm_inst,
383 					       clkdm1->clkdm_offs +
384 					       OMAP4_CM_STATICDEP,
385 					       (1 << clkdm2->dep_bit));
386 }
387 
388 static int omap4_clkdm_clear_all_wkup_sleep_deps(struct clockdomain *clkdm)
389 {
390 	struct clkdm_dep *cd;
391 	u32 mask = 0;
392 
393 	if (!clkdm->prcm_partition)
394 		return 0;
395 
396 	for (cd = clkdm->wkdep_srcs; cd && cd->clkdm_name; cd++) {
397 		if (!cd->clkdm)
398 			continue; /* only happens if data is erroneous */
399 
400 		mask |= 1 << cd->clkdm->dep_bit;
401 		cd->wkdep_usecount = 0;
402 	}
403 
404 	omap4_cminst_clear_inst_reg_bits(mask, clkdm->prcm_partition,
405 					 clkdm->cm_inst, clkdm->clkdm_offs +
406 					 OMAP4_CM_STATICDEP);
407 	return 0;
408 }
409 
410 static int omap4_clkdm_sleep(struct clockdomain *clkdm)
411 {
412 	if (clkdm->flags & CLKDM_CAN_HWSUP)
413 		omap4_cminst_clkdm_enable_hwsup(clkdm->prcm_partition,
414 						clkdm->cm_inst,
415 						clkdm->clkdm_offs);
416 	else if (clkdm->flags & CLKDM_CAN_FORCE_SLEEP)
417 		omap4_cminst_clkdm_force_sleep(clkdm->prcm_partition,
418 					       clkdm->cm_inst,
419 					       clkdm->clkdm_offs);
420 	else
421 		return -EINVAL;
422 
423 	return 0;
424 }
425 
426 static int omap4_clkdm_wakeup(struct clockdomain *clkdm)
427 {
428 	omap4_cminst_clkdm_force_wakeup(clkdm->prcm_partition,
429 					clkdm->cm_inst, clkdm->clkdm_offs);
430 	return 0;
431 }
432 
433 static void omap4_clkdm_allow_idle(struct clockdomain *clkdm)
434 {
435 	omap4_cminst_clkdm_enable_hwsup(clkdm->prcm_partition,
436 					clkdm->cm_inst, clkdm->clkdm_offs);
437 }
438 
439 static void omap4_clkdm_deny_idle(struct clockdomain *clkdm)
440 {
441 	if (clkdm->flags & CLKDM_CAN_FORCE_WAKEUP)
442 		omap4_clkdm_wakeup(clkdm);
443 	else
444 		omap4_cminst_clkdm_disable_hwsup(clkdm->prcm_partition,
445 						 clkdm->cm_inst,
446 						 clkdm->clkdm_offs);
447 }
448 
449 static int omap4_clkdm_clk_enable(struct clockdomain *clkdm)
450 {
451 	if (clkdm->flags & CLKDM_CAN_FORCE_WAKEUP)
452 		return omap4_clkdm_wakeup(clkdm);
453 
454 	return 0;
455 }
456 
457 static int omap4_clkdm_clk_disable(struct clockdomain *clkdm)
458 {
459 	bool hwsup = false;
460 
461 	if (!clkdm->prcm_partition)
462 		return 0;
463 
464 	/*
465 	 * The CLKDM_MISSING_IDLE_REPORTING flag documentation has
466 	 * more details on the unpleasant problem this is working
467 	 * around
468 	 */
469 	if (clkdm->flags & CLKDM_MISSING_IDLE_REPORTING &&
470 	    !(clkdm->flags & CLKDM_CAN_FORCE_SLEEP)) {
471 		omap4_clkdm_allow_idle(clkdm);
472 		return 0;
473 	}
474 
475 	hwsup = omap4_cminst_is_clkdm_in_hwsup(clkdm->prcm_partition,
476 					clkdm->cm_inst, clkdm->clkdm_offs);
477 
478 	if (!hwsup && (clkdm->flags & CLKDM_CAN_FORCE_SLEEP))
479 		omap4_clkdm_sleep(clkdm);
480 
481 	return 0;
482 }
483 
484 struct clkdm_ops omap4_clkdm_operations = {
485 	.clkdm_add_wkdep	= omap4_clkdm_add_wkup_sleep_dep,
486 	.clkdm_del_wkdep	= omap4_clkdm_del_wkup_sleep_dep,
487 	.clkdm_read_wkdep	= omap4_clkdm_read_wkup_sleep_dep,
488 	.clkdm_clear_all_wkdeps	= omap4_clkdm_clear_all_wkup_sleep_deps,
489 	.clkdm_add_sleepdep	= omap4_clkdm_add_wkup_sleep_dep,
490 	.clkdm_del_sleepdep	= omap4_clkdm_del_wkup_sleep_dep,
491 	.clkdm_read_sleepdep	= omap4_clkdm_read_wkup_sleep_dep,
492 	.clkdm_clear_all_sleepdeps	= omap4_clkdm_clear_all_wkup_sleep_deps,
493 	.clkdm_sleep		= omap4_clkdm_sleep,
494 	.clkdm_wakeup		= omap4_clkdm_wakeup,
495 	.clkdm_allow_idle	= omap4_clkdm_allow_idle,
496 	.clkdm_deny_idle	= omap4_clkdm_deny_idle,
497 	.clkdm_clk_enable	= omap4_clkdm_clk_enable,
498 	.clkdm_clk_disable	= omap4_clkdm_clk_disable,
499 };
500 
501 struct clkdm_ops am43xx_clkdm_operations = {
502 	.clkdm_sleep		= omap4_clkdm_sleep,
503 	.clkdm_wakeup		= omap4_clkdm_wakeup,
504 	.clkdm_allow_idle	= omap4_clkdm_allow_idle,
505 	.clkdm_deny_idle	= omap4_clkdm_deny_idle,
506 	.clkdm_clk_enable	= omap4_clkdm_clk_enable,
507 	.clkdm_clk_disable	= omap4_clkdm_clk_disable,
508 };
509 
510 static struct cm_ll_data omap4xxx_cm_ll_data = {
511 	.wait_module_ready	= &omap4_cminst_wait_module_ready,
512 	.wait_module_idle	= &omap4_cminst_wait_module_idle,
513 	.module_enable		= &omap4_cminst_module_enable,
514 	.module_disable		= &omap4_cminst_module_disable,
515 };
516 
517 int __init omap4_cm_init(void)
518 {
519 	return cm_register(&omap4xxx_cm_ll_data);
520 }
521 
522 static void __exit omap4_cm_exit(void)
523 {
524 	cm_unregister(&omap4xxx_cm_ll_data);
525 }
526 __exitcall(omap4_cm_exit);
527