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
58static 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 */
66static 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
76static 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 */
87static 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 */
104static 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 */
115static 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 */
124static 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 */
133static 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
146static 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
151static 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
157static 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 */
182static 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 */
201static 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 */
221static 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 */
236static 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 */
250static 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
259static 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 */
276static 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 */
302static 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 */
326static 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 */
345static 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
358static 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
368static 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
378static 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
388static 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
410static 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
426static 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
433static 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
439static 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
449static 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
457static 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
484struct 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
501struct 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
510static 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
517int __init omap4_cm_init(const struct omap_prcm_init_data *data)
518{
519	omap_cm_base_init();
520
521	return cm_register(&omap4xxx_cm_ll_data);
522}
523
524static void __exit omap4_cm_exit(void)
525{
526	cm_unregister(&omap4xxx_cm_ll_data);
527}
528__exitcall(omap4_cm_exit);
529