aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/acpi/acpica/hwregs.c
blob: 9c8162128c2b943b2d970c6f13e699d367e9cdf3 (plain) (blame)
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
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419

/*******************************************************************************
 *
 * Module Name: hwregs - Read/write access functions for the various ACPI
 *                       control and status registers.
 *
 ******************************************************************************/

/*
 * Copyright (C) 2000 - 2008, Intel Corp.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 */

#include <acpi/acpi.h>
#include "accommon.h"
#include "acnamesp.h"
#include "acevents.h"

#define _COMPONENT          ACPI_HARDWARE
ACPI_MODULE_NAME("hwregs")

/* Local Prototypes */
static acpi_status
acpi_hw_read_multiple(u32 *value,
		      struct acpi_generic_address *register_a,
		      struct acpi_generic_address *register_b);

static acpi_status
acpi_hw_write_multiple(u32 value,
		       struct acpi_generic_address *register_a,
		       struct acpi_generic_address *register_b);

/*******************************************************************************
 *
 * FUNCTION:    acpi_hw_clear_acpi_status
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Clears all fixed and general purpose status bits
 *
 ******************************************************************************/

acpi_status acpi_hw_clear_acpi_status(void)
{
	acpi_status status;
	acpi_cpu_flags lock_flags = 0;

	ACPI_FUNCTION_TRACE(hw_clear_acpi_status);

	ACPI_DEBUG_PRINT((ACPI_DB_IO, "About to write %04X to %0llX\n",
			  ACPI_BITMASK_ALL_FIXED_STATUS,
			  acpi_gbl_xpm1a_status.address));

	lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock);

	/* Clear the fixed events in PM1 A/B */

	status = acpi_hw_register_write(ACPI_REGISTER_PM1_STATUS,
					ACPI_BITMASK_ALL_FIXED_STATUS);
	if (ACPI_FAILURE(status)) {
		goto unlock_and_exit;
	}

	/* Clear the GPE Bits in all GPE registers in all GPE blocks */

	status = acpi_ev_walk_gpe_list(acpi_hw_clear_gpe_block, NULL);

      unlock_and_exit:
	acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags);
	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_hw_get_register_bit_mask
 *
 * PARAMETERS:  register_id         - Index of ACPI Register to access
 *
 * RETURN:      The bitmask to be used when accessing the register
 *
 * DESCRIPTION: Map register_id into a register bitmask.
 *
 ******************************************************************************/

struct acpi_bit_register_info *acpi_hw_get_bit_register_info(u32 register_id)
{
	ACPI_FUNCTION_ENTRY();

	if (register_id > ACPI_BITREG_MAX) {
		ACPI_ERROR((AE_INFO, "Invalid BitRegister ID: %X",
			    register_id));
		return (NULL);
	}

	return (&acpi_gbl_bit_register_info[register_id]);
}

/******************************************************************************
 *
 * FUNCTION:    acpi_hw_register_read
 *
 * PARAMETERS:  register_id         - ACPI Register ID
 *              return_value        - Where the register value is returned
 *
 * RETURN:      Status and the value read.
 *
 * DESCRIPTION: Read from the specified ACPI register
 *
 ******************************************************************************/
acpi_status
acpi_hw_register_read(u32 register_id, u32 * return_value)
{
	u32 value = 0;
	acpi_status status;

	ACPI_FUNCTION_TRACE(hw_register_read);

	switch (register_id) {
	case ACPI_REGISTER_PM1_STATUS:	/* PM1 A/B: 16-bit access each */

		status = acpi_hw_read_multiple(&value,
					       &acpi_gbl_xpm1a_status,
					       &acpi_gbl_xpm1b_status);
		break;

	case ACPI_REGISTER_PM1_ENABLE:	/* PM1 A/B: 16-bit access each */

		status = acpi_hw_read_multiple(&value,
					       &acpi_gbl_xpm1a_enable,
					       &acpi_gbl_xpm1b_enable);
		break;

	case ACPI_REGISTER_PM1_CONTROL:	/* PM1 A/B: 16-bit access each */

		status = acpi_hw_read_multiple(&value,
					       &acpi_gbl_FADT.
					       xpm1a_control_block,
					       &acpi_gbl_FADT.
					       xpm1b_control_block);
		break;

	case ACPI_REGISTER_PM2_CONTROL:	/* 8-bit access */

		status = acpi_read(&value, &acpi_gbl_FADT.xpm2_control_block);
		break;

	case ACPI_REGISTER_PM_TIMER:	/* 32-bit access */

		status = acpi_read(&value, &acpi_gbl_FADT.xpm_timer_block);
		break;

	case ACPI_REGISTER_SMI_COMMAND_BLOCK:	/* 8-bit access */

		status =
		    acpi_os_read_port(acpi_gbl_FADT.smi_command, &value, 8);
		break;

	default:
		ACPI_ERROR((AE_INFO, "Unknown Register ID: %X", register_id));
		status = AE_BAD_PARAMETER;
		break;
	}

	if (ACPI_SUCCESS(status)) {
		*return_value = value;
	}

	return_ACPI_STATUS(status);
}

/******************************************************************************
 *
 * FUNCTION:    acpi_hw_register_write
 *
 * PARAMETERS:  register_id         - ACPI Register ID
 *              Value               - The value to write
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Write to the specified ACPI register
 *
 * NOTE: In accordance with the ACPI specification, this function automatically
 * preserves the value of the following bits, meaning that these bits cannot be
 * changed via this interface:
 *
 * PM1_CONTROL[0] = SCI_EN
 * PM1_CONTROL[9]
 * PM1_STATUS[11]
 *
 * ACPI References:
 * 1) Hardware Ignored Bits: When software writes to a register with ignored
 *      bit fields, it preserves the ignored bit fields
 * 2) SCI_EN: OSPM always preserves this bit position
 *
 ******************************************************************************/

acpi_status acpi_hw_register_write(u32 register_id, u32 value)
{
	acpi_status status;
	u32 read_value;

	ACPI_FUNCTION_TRACE(hw_register_write);

	switch (register_id) {
	case ACPI_REGISTER_PM1_STATUS:	/* PM1 A/B: 16-bit access each */

		/* Perform a read first to preserve certain bits (per ACPI spec) */

		status = acpi_hw_read_multiple(&read_value,
					       &acpi_gbl_xpm1a_status,
					       &acpi_gbl_xpm1b_status);
		if (ACPI_FAILURE(status)) {
			goto exit;
		}

		/* Insert the bits to be preserved */

		ACPI_INSERT_BITS(value, ACPI_PM1_STATUS_PRESERVED_BITS,
				 read_value);

		/* Now we can write the data */

		status = acpi_hw_write_multiple(value,
						&acpi_gbl_xpm1a_status,
						&acpi_gbl_xpm1b_status);
		break;

	case ACPI_REGISTER_PM1_ENABLE:	/* PM1 A/B: 16-bit access */

		status = acpi_hw_write_multiple(value,
						&acpi_gbl_xpm1a_enable,
						&acpi_gbl_xpm1b_enable);
		break;

	case ACPI_REGISTER_PM1_CONTROL:	/* PM1 A/B: 16-bit access each */

		/*
		 * Perform a read first to preserve certain bits (per ACPI spec)
		 * Note: This includes SCI_EN, we never want to change this bit
		 */
		status = acpi_hw_read_multiple(&read_value,
					       &acpi_gbl_FADT.
					       xpm1a_control_block,
					       &acpi_gbl_FADT.
					       xpm1b_control_block);
		if (ACPI_FAILURE(status)) {
			goto exit;
		}

		/* Insert the bits to be preserved */

		ACPI_INSERT_BITS(value, ACPI_PM1_CONTROL_PRESERVED_BITS,
				 read_value);

		/* Now we can write the data */

		status = acpi_hw_write_multiple(value,
						&acpi_gbl_FADT.
						xpm1a_control_block,
						&acpi_gbl_FADT.
						xpm1b_control_block);
		break;

	case ACPI_REGISTER_PM1A_CONTROL:	/* 16-bit access */

		status = acpi_write(value, &acpi_gbl_FADT.xpm1a_control_block);
		break;

	case ACPI_REGISTER_PM1B_CONTROL:	/* 16-bit access */

		status = acpi_write(value, &acpi_gbl_FADT.xpm1b_control_block);
		break;

	case ACPI_REGISTER_PM2_CONTROL:	/* 8-bit access */

		status = acpi_write(value, &acpi_gbl_FADT.xpm2_control_block);
		break;

	case ACPI_REGISTER_PM_TIMER:	/* 32-bit access */

		status = acpi_write(value, &acpi_gbl_FADT.xpm_timer_block);
		break;

	case ACPI_REGISTER_SMI_COMMAND_BLOCK:	/* 8-bit access */

		/* SMI_CMD is currently always in IO space */

		status =
		    acpi_os_write_port(acpi_gbl_FADT.smi_command, value, 8);
		break;

	default:
		ACPI_ERROR((AE_INFO, "Unknown Register ID: %X", register_id));
		status = AE_BAD_PARAMETER;
		break;
	}

      exit:
	return_ACPI_STATUS(status);
}

/******************************************************************************
 *
 * FUNCTION:    acpi_hw_read_multiple
 *
 * PARAMETERS:  Value               - Where the register value is returned
 *              register_a           - First ACPI register (required)
 *              register_b           - Second ACPI register (optional)
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Read from the specified two-part ACPI register (such as PM1 A/B)
 *
 ******************************************************************************/

static acpi_status
acpi_hw_read_multiple(u32 *value,
		      struct acpi_generic_address *register_a,
		      struct acpi_generic_address *register_b)
{
	u32 value_a = 0;
	u32 value_b = 0;
	acpi_status status;

	/* The first register is always required */

	status = acpi_read(&value_a, register_a);
	if (ACPI_FAILURE(status)) {
		return (status);
	}

	/* Second register is optional */

	if (register_b->address) {
		status = acpi_read(&value_b, register_b);
		if (ACPI_FAILURE(status)) {
			return (status);
		}
	}

	/* Shift the B bits above the A bits */

	*value = value_a | (value_b << register_a->bit_width);
	return (AE_OK);
}

/******************************************************************************
 *
 * FUNCTION:    acpi_hw_write_multiple
 *
 * PARAMETERS:  Value               - The value to write
 *              register_a           - First ACPI register (required)
 *              register_b           - Second ACPI register (optional)
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Write to the specified two-part ACPI register (such as PM1 A/B)
 *
 ******************************************************************************/

static acpi_status
acpi_hw_write_multiple(u32 value,
		       struct acpi_generic_address *register_a,
		       struct acpi_generic_address *register_b)
{
	acpi_status status;

	/* The first register is always required */

	status = acpi_write(value, register_a);
	if (ACPI_FAILURE(status)) {
		return (status);
	}

	/* Second register is optional */

	if (register_b->address) {

		/* Normalize the B bits before write */

		status = acpi_write(value >> register_a->bit_width, register_b);
	}

	return (status);
}