summaryrefslogtreecommitdiff
path: root/arch/arm/mach-omap2/cm33xx.c
blob: 325a515765766c1757c5fd858e9bd8b3c226f44e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
/*
 * AM33XX CM functions
 *
 * Copyright (C) 2011-2012 Texas Instruments Incorporated - http://www.ti.com/
 * Vaibhav Hiremath <hvaibhav@ti.com>
 *
 * Reference taken from from OMAP4 cminst44xx.c
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation version 2.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 * kind, whether express or implied; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/io.h>

#include "clockdomain.h"
#include "cm.h"
#include "cm33xx.h"
#include "cm-regbits-34xx.h"
#include "cm-regbits-33xx.h"
#include "prm33xx.h"

/*
 * CLKCTRL_IDLEST_*: possible values for the CM_*_CLKCTRL.IDLEST bitfield:
 *
 *   0x0 func:     Module is fully functional, including OCP
 *   0x1 trans:    Module is performing transition: wakeup, or sleep, or sleep
 *                 abortion
 *   0x2 idle:     Module is in Idle mode (only OCP part). It is functional if
 *                 using separate functional clock
 *   0x3 disabled: Module is disabled and cannot be accessed
 *
 */
#define CLKCTRL_IDLEST_FUNCTIONAL		0x0
#define CLKCTRL_IDLEST_INTRANSITION		0x1
#define CLKCTRL_IDLEST_INTERFACE_IDLE		0x2
#define CLKCTRL_IDLEST_DISABLED			0x3

/* Private functions */

/* Read a register in a CM instance */
static inline u32 am33xx_cm_read_reg(s16 inst, u16 idx)
{
	return __raw_readl(cm_base + inst + idx);
}

/* Write into a register in a CM */
static inline void am33xx_cm_write_reg(u32 val, s16 inst, u16 idx)
{
	__raw_writel(val, cm_base + inst + idx);
}

/* Read-modify-write a register in CM */
static inline u32 am33xx_cm_rmw_reg_bits(u32 mask, u32 bits, s16 inst, s16 idx)
{
	u32 v;

	v = am33xx_cm_read_reg(inst, idx);
	v &= ~mask;
	v |= bits;
	am33xx_cm_write_reg(v, inst, idx);

	return v;
}

static inline u32 am33xx_cm_set_reg_bits(u32 bits, s16 inst, s16 idx)
{
	return am33xx_cm_rmw_reg_bits(bits, bits, inst, idx);
}

static inline u32 am33xx_cm_clear_reg_bits(u32 bits, s16 inst, s16 idx)
{
	return am33xx_cm_rmw_reg_bits(bits, 0x0, inst, idx);
}

static inline u32 am33xx_cm_read_reg_bits(u16 inst, s16 idx, u32 mask)
{
	u32 v;

	v = am33xx_cm_read_reg(inst, idx);
	v &= mask;
	v >>= __ffs(mask);

	return v;
}

/**
 * _clkctrl_idlest - read a CM_*_CLKCTRL register; mask & shift IDLEST bitfield
 * @inst: CM instance register offset (*_INST macro)
 * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
 * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro)
 *
 * Return the IDLEST bitfield of a CM_*_CLKCTRL register, shifted down to
 * bit 0.
 */
static u32 _clkctrl_idlest(u16 inst, s16 cdoffs, u16 clkctrl_offs)
{
	u32 v = am33xx_cm_read_reg(inst, clkctrl_offs);
	v &= AM33XX_IDLEST_MASK;
	v >>= AM33XX_IDLEST_SHIFT;
	return v;
}

/**
 * _is_module_ready - can module registers be accessed without causing an abort?
 * @inst: CM instance register offset (*_INST macro)
 * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
 * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro)
 *
 * Returns true if the module's CM_*_CLKCTRL.IDLEST bitfield is either
 * *FUNCTIONAL or *INTERFACE_IDLE; false otherwise.
 */
static bool _is_module_ready(u16 inst, s16 cdoffs, u16 clkctrl_offs)
{
	u32 v;

	v = _clkctrl_idlest(inst, cdoffs, clkctrl_offs);

	return (v == CLKCTRL_IDLEST_FUNCTIONAL ||
		v == CLKCTRL_IDLEST_INTERFACE_IDLE) ? true : false;
}

/**
 * _clktrctrl_write - write @c to a CM_CLKSTCTRL.CLKTRCTRL register bitfield
 * @c: CLKTRCTRL register bitfield (LSB = bit 0, i.e., unshifted)
 * @inst: CM instance register offset (*_INST macro)
 * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
 *
 * @c must be the unshifted value for CLKTRCTRL - i.e., this function
 * will handle the shift itself.
 */
static void _clktrctrl_write(u8 c, s16 inst, u16 cdoffs)
{
	u32 v;

	v = am33xx_cm_read_reg(inst, cdoffs);
	v &= ~AM33XX_CLKTRCTRL_MASK;
	v |= c << AM33XX_CLKTRCTRL_SHIFT;
	am33xx_cm_write_reg(v, inst, cdoffs);
}

/* Public functions */

/**
 * am33xx_cm_is_clkdm_in_hwsup - is a clockdomain in hwsup idle mode?
 * @inst: CM instance register offset (*_INST macro)
 * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
 *
 * Returns true if the clockdomain referred to by (@inst, @cdoffs)
 * is in hardware-supervised idle mode, or 0 otherwise.
 */
bool am33xx_cm_is_clkdm_in_hwsup(s16 inst, u16 cdoffs)
{
	u32 v;

	v = am33xx_cm_read_reg(inst, cdoffs);
	v &= AM33XX_CLKTRCTRL_MASK;
	v >>= AM33XX_CLKTRCTRL_SHIFT;

	return (v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) ? true : false;
}

/**
 * am33xx_cm_clkdm_enable_hwsup - put a clockdomain in hwsup-idle mode
 * @inst: CM instance register offset (*_INST macro)
 * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
 *
 * Put a clockdomain referred to by (@inst, @cdoffs) into
 * hardware-supervised idle mode.  No return value.
 */
void am33xx_cm_clkdm_enable_hwsup(s16 inst, u16 cdoffs)
{
	_clktrctrl_write(OMAP34XX_CLKSTCTRL_ENABLE_AUTO, inst, cdoffs);
}

/**
 * am33xx_cm_clkdm_disable_hwsup - put a clockdomain in swsup-idle mode
 * @inst: CM instance register offset (*_INST macro)
 * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
 *
 * Put a clockdomain referred to by (@inst, @cdoffs) into
 * software-supervised idle mode, i.e., controlled manually by the
 * Linux OMAP clockdomain code.  No return value.
 */
void am33xx_cm_clkdm_disable_hwsup(s16 inst, u16 cdoffs)
{
	_clktrctrl_write(OMAP34XX_CLKSTCTRL_DISABLE_AUTO, inst, cdoffs);
}

/**
 * am33xx_cm_clkdm_force_sleep - try to put a clockdomain into idle
 * @inst: CM instance register offset (*_INST macro)
 * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
 *
 * Put a clockdomain referred to by (@inst, @cdoffs) into idle
 * No return value.
 */
void am33xx_cm_clkdm_force_sleep(s16 inst, u16 cdoffs)
{
	_clktrctrl_write(OMAP34XX_CLKSTCTRL_FORCE_SLEEP, inst, cdoffs);
}

/**
 * am33xx_cm_clkdm_force_wakeup - try to take a clockdomain out of idle
 * @inst: CM instance register offset (*_INST macro)
 * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
 *
 * Take a clockdomain referred to by (@inst, @cdoffs) out of idle,
 * waking it up.  No return value.
 */
void am33xx_cm_clkdm_force_wakeup(s16 inst, u16 cdoffs)
{
	_clktrctrl_write(OMAP34XX_CLKSTCTRL_FORCE_WAKEUP, inst, cdoffs);
}

/*
 *
 */

/**
 * am33xx_cm_wait_module_ready - wait for a module to be in 'func' state
 * @inst: CM instance register offset (*_INST macro)
 * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
 * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro)
 *
 * Wait for the module IDLEST to be functional. If the idle state is in any
 * the non functional state (trans, idle or disabled), module and thus the
 * sysconfig cannot be accessed and will probably lead to an "imprecise
 * external abort"
 */
int am33xx_cm_wait_module_ready(u16 inst, s16 cdoffs, u16 clkctrl_offs)
{
	int i = 0;

	omap_test_timeout(_is_module_ready(inst, cdoffs, clkctrl_offs),
			  MAX_MODULE_READY_TIME, i);

	return (i < MAX_MODULE_READY_TIME) ? 0 : -EBUSY;
}

/**
 * am33xx_cm_wait_module_idle - wait for a module to be in 'disabled'
 * state
 * @inst: CM instance register offset (*_INST macro)
 * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
 * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro)
 *
 * Wait for the module IDLEST to be disabled. Some PRCM transition,
 * like reset assertion or parent clock de-activation must wait the
 * module to be fully disabled.
 */
int am33xx_cm_wait_module_idle(u16 inst, s16 cdoffs, u16 clkctrl_offs)
{
	int i = 0;

	if (!clkctrl_offs)
		return 0;

	omap_test_timeout((_clkctrl_idlest(inst, cdoffs, clkctrl_offs) ==
				CLKCTRL_IDLEST_DISABLED),
				MAX_MODULE_READY_TIME, i);

	return (i < MAX_MODULE_READY_TIME) ? 0 : -EBUSY;
}

/**
 * am33xx_cm_module_enable - Enable the modulemode inside CLKCTRL
 * @mode: Module mode (SW or HW)
 * @inst: CM instance register offset (*_INST macro)
 * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
 * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro)
 *
 * No return value.
 */
void am33xx_cm_module_enable(u8 mode, u16 inst, s16 cdoffs, u16 clkctrl_offs)
{
	u32 v;

	v = am33xx_cm_read_reg(inst, clkctrl_offs);
	v &= ~AM33XX_MODULEMODE_MASK;
	v |= mode << AM33XX_MODULEMODE_SHIFT;
	am33xx_cm_write_reg(v, inst, clkctrl_offs);
}

/**
 * am33xx_cm_module_disable - Disable the module inside CLKCTRL
 * @inst: CM instance register offset (*_INST macro)
 * @cdoffs: Clockdomain register offset (*_CDOFFS macro)
 * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro)
 *
 * No return value.
 */
void am33xx_cm_module_disable(u16 inst, s16 cdoffs, u16 clkctrl_offs)
{
	u32 v;

	v = am33xx_cm_read_reg(inst, clkctrl_offs);
	v &= ~AM33XX_MODULEMODE_MASK;
	am33xx_cm_write_reg(v, inst, clkctrl_offs);
}

/*
 * Clockdomain low-level functions
 */

static int am33xx_clkdm_sleep(struct clockdomain *clkdm)
{
	am33xx_cm_clkdm_force_sleep(clkdm->cm_inst, clkdm->clkdm_offs);
	return 0;
}

static int am33xx_clkdm_wakeup(struct clockdomain *clkdm)
{
	am33xx_cm_clkdm_force_wakeup(clkdm->cm_inst, clkdm->clkdm_offs);
	return 0;
}

static void am33xx_clkdm_allow_idle(struct clockdomain *clkdm)
{
	am33xx_cm_clkdm_enable_hwsup(clkdm->cm_inst, clkdm->clkdm_offs);
}

static void am33xx_clkdm_deny_idle(struct clockdomain *clkdm)
{
	am33xx_cm_clkdm_disable_hwsup(clkdm->cm_inst, clkdm->clkdm_offs);
}

static int am33xx_clkdm_clk_enable(struct clockdomain *clkdm)
{
	if (clkdm->flags & CLKDM_CAN_FORCE_WAKEUP)
		return am33xx_clkdm_wakeup(clkdm);

	return 0;
}

static int am33xx_clkdm_clk_disable(struct clockdomain *clkdm)
{
	bool hwsup = false;

	hwsup = am33xx_cm_is_clkdm_in_hwsup(clkdm->cm_inst, clkdm->clkdm_offs);

	if (!hwsup && (clkdm->flags & CLKDM_CAN_FORCE_SLEEP))
		am33xx_clkdm_sleep(clkdm);

	return 0;
}

struct clkdm_ops am33xx_clkdm_operations = {
	.clkdm_sleep		= am33xx_clkdm_sleep,
	.clkdm_wakeup		= am33xx_clkdm_wakeup,
	.clkdm_allow_idle	= am33xx_clkdm_allow_idle,
	.clkdm_deny_idle	= am33xx_clkdm_deny_idle,
	.clkdm_clk_enable	= am33xx_clkdm_clk_enable,
	.clkdm_clk_disable	= am33xx_clkdm_clk_disable,
};