1
2 /*******************************************************************************
3 *
4 * Module Name: hwregs - Read/write access functions for the various ACPI
5 * control and status registers.
6 *
7 ******************************************************************************/
8
9 /*
10 * Copyright (C) 2000 - 2011, Intel Corp.
11 * All rights reserved.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions, and the following disclaimer,
18 * without modification.
19 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
20 * substantially similar to the "NO WARRANTY" disclaimer below
21 * ("Disclaimer") and any redistribution must be conditioned upon
22 * including a substantially similar Disclaimer requirement for further
23 * binary redistribution.
24 * 3. Neither the names of the above-listed copyright holders nor the names
25 * of any contributors may be used to endorse or promote products derived
26 * from this software without specific prior written permission.
27 *
28 * Alternatively, this software may be distributed under the terms of the
29 * GNU General Public License ("GPL") version 2 as published by the Free
30 * Software Foundation.
31 *
32 * NO WARRANTY
33 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
34 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
35 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
36 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
37 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
38 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
39 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
40 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
41 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
42 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
43 * POSSIBILITY OF SUCH DAMAGES.
44 */
45
46 #define __HWREGS_C__
47
48 #include "acpi.h"
49 #include "accommon.h"
50 #include "acevents.h"
51
52 #define _COMPONENT ACPI_HARDWARE
53 ACPI_MODULE_NAME ("hwregs")
54
55
56 /* Local Prototypes */
57
58 static ACPI_STATUS
59 AcpiHwReadMultiple (
60 UINT32 *Value,
61 ACPI_GENERIC_ADDRESS *RegisterA,
62 ACPI_GENERIC_ADDRESS *RegisterB);
63
64 static ACPI_STATUS
65 AcpiHwWriteMultiple (
66 UINT32 Value,
67 ACPI_GENERIC_ADDRESS *RegisterA,
68 ACPI_GENERIC_ADDRESS *RegisterB);
69
70
71 /******************************************************************************
72 *
73 * FUNCTION: AcpiHwValidateRegister
74 *
75 * PARAMETERS: Reg - GAS register structure
76 * MaxBitWidth - Max BitWidth supported (32 or 64)
77 * Address - Pointer to where the gas->address
78 * is returned
79 *
80 * RETURN: Status
81 *
82 * DESCRIPTION: Validate the contents of a GAS register. Checks the GAS
83 * pointer, Address, SpaceId, BitWidth, and BitOffset.
84 *
85 ******************************************************************************/
86
87 ACPI_STATUS
88 AcpiHwValidateRegister (
89 ACPI_GENERIC_ADDRESS *Reg,
90 UINT8 MaxBitWidth,
91 UINT64 *Address)
92 {
93
94 /* Must have a valid pointer to a GAS structure */
95
96 if (!Reg)
97 {
98 return (AE_BAD_PARAMETER);
99 }
100
101 /*
102 * Copy the target address. This handles possible alignment issues.
103 * Address must not be null. A null address also indicates an optional
104 * ACPI register that is not supported, so no error message.
105 */
106 ACPI_MOVE_64_TO_64 (Address, &Reg->Address);
107 if (!(*Address))
108 {
109 return (AE_BAD_ADDRESS);
110 }
111
112 /* Validate the SpaceID */
113
114 if ((Reg->SpaceId != ACPI_ADR_SPACE_SYSTEM_MEMORY) &&
115 (Reg->SpaceId != ACPI_ADR_SPACE_SYSTEM_IO))
116 {
117 ACPI_ERROR ((AE_INFO,
118 "Unsupported address space: 0x%X", Reg->SpaceId));
119 return (AE_SUPPORT);
120 }
121
122 /* Validate the BitWidth */
123
124 if ((Reg->BitWidth != 8) &&
125 (Reg->BitWidth != 16) &&
126 (Reg->BitWidth != 32) &&
127 (Reg->BitWidth != MaxBitWidth))
128 {
129 ACPI_ERROR ((AE_INFO,
130 "Unsupported register bit width: 0x%X", Reg->BitWidth));
131 return (AE_SUPPORT);
132 }
133
134 /* Validate the BitOffset. Just a warning for now. */
135
136 if (Reg->BitOffset != 0)
137 {
138 ACPI_WARNING ((AE_INFO,
139 "Unsupported register bit offset: 0x%X", Reg->BitOffset));
140 }
141
142 return (AE_OK);
143 }
144
145
146 /******************************************************************************
147 *
148 * FUNCTION: AcpiHwRead
149 *
150 * PARAMETERS: Value - Where the value is returned
151 * Reg - GAS register structure
152 *
153 * RETURN: Status
154 *
155 * DESCRIPTION: Read from either memory or IO space. This is a 32-bit max
156 * version of AcpiRead, used internally since the overhead of
157 * 64-bit values is not needed.
158 *
159 * LIMITATIONS: <These limitations also apply to AcpiHwWrite>
160 * BitWidth must be exactly 8, 16, or 32.
161 * SpaceID must be SystemMemory or SystemIO.
162 * BitOffset and AccessWidth are currently ignored, as there has
163 * not been a need to implement these.
164 *
165 ******************************************************************************/
166
167 ACPI_STATUS
168 AcpiHwRead (
169 UINT32 *Value,
170 ACPI_GENERIC_ADDRESS *Reg)
171 {
172 UINT64 Address;
173 ACPI_STATUS Status;
174
175
176 ACPI_FUNCTION_NAME (HwRead);
177
178
179 /* Validate contents of the GAS register */
180
181 Status = AcpiHwValidateRegister (Reg, 32, &Address);
182 if (ACPI_FAILURE (Status))
183 {
184 return (Status);
185 }
186
187 /* Initialize entire 32-bit return value to zero */
188
189 *Value = 0;
190
191 /*
192 * Two address spaces supported: Memory or IO. PCI_Config is
193 * not supported here because the GAS structure is insufficient
194 */
195 if (Reg->SpaceId == ACPI_ADR_SPACE_SYSTEM_MEMORY)
196 {
197 Status = AcpiOsReadMemory ((ACPI_PHYSICAL_ADDRESS)
198 Address, Value, Reg->BitWidth);
199 }
200 else /* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */
201 {
202 Status = AcpiHwReadPort ((ACPI_IO_ADDRESS)
203 Address, Value, Reg->BitWidth);
204 }
205
206 ACPI_DEBUG_PRINT ((ACPI_DB_IO,
207 "Read: %8.8X width %2d from %8.8X%8.8X (%s)\n",
208 *Value, Reg->BitWidth, ACPI_FORMAT_UINT64 (Address),
209 AcpiUtGetRegionName (Reg->SpaceId)));
210
211 return (Status);
212 }
213
214
215 /******************************************************************************
216 *
217 * FUNCTION: AcpiHwWrite
218 *
219 * PARAMETERS: Value - Value to be written
220 * Reg - GAS register structure
221 *
222 * RETURN: Status
223 *
224 * DESCRIPTION: Write to either memory or IO space. This is a 32-bit max
225 * version of AcpiWrite, used internally since the overhead of
226 * 64-bit values is not needed.
227 *
228 ******************************************************************************/
229
230 ACPI_STATUS
231 AcpiHwWrite (
232 UINT32 Value,
233 ACPI_GENERIC_ADDRESS *Reg)
234 {
235 UINT64 Address;
236 ACPI_STATUS Status;
237
238
239 ACPI_FUNCTION_NAME (HwWrite);
240
241
242 /* Validate contents of the GAS register */
243
244 Status = AcpiHwValidateRegister (Reg, 32, &Address);
245 if (ACPI_FAILURE (Status))
246 {
247 return (Status);
248 }
249
250 /*
251 * Two address spaces supported: Memory or IO. PCI_Config is
252 * not supported here because the GAS structure is insufficient
253 */
254 if (Reg->SpaceId == ACPI_ADR_SPACE_SYSTEM_MEMORY)
255 {
256 Status = AcpiOsWriteMemory ((ACPI_PHYSICAL_ADDRESS)
257 Address, Value, Reg->BitWidth);
258 }
259 else /* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */
260 {
261 Status = AcpiHwWritePort ((ACPI_IO_ADDRESS)
262 Address, Value, Reg->BitWidth);
263 }
264
265 ACPI_DEBUG_PRINT ((ACPI_DB_IO,
266 "Wrote: %8.8X width %2d to %8.8X%8.8X (%s)\n",
267 Value, Reg->BitWidth, ACPI_FORMAT_UINT64 (Address),
268 AcpiUtGetRegionName (Reg->SpaceId)));
269
270 return (Status);
271 }
272
273
274 /*******************************************************************************
275 *
276 * FUNCTION: AcpiHwClearAcpiStatus
277 *
278 * PARAMETERS: None
279 *
280 * RETURN: Status
281 *
282 * DESCRIPTION: Clears all fixed and general purpose status bits
283 *
284 ******************************************************************************/
285
286 ACPI_STATUS
287 AcpiHwClearAcpiStatus (
288 void)
289 {
290 ACPI_STATUS Status;
291 ACPI_CPU_FLAGS LockFlags = 0;
292
293
294 ACPI_FUNCTION_TRACE (HwClearAcpiStatus);
295
296
297 ACPI_DEBUG_PRINT ((ACPI_DB_IO, "About to write %04X to %8.8X%8.8X\n",
298 ACPI_BITMASK_ALL_FIXED_STATUS,
299 ACPI_FORMAT_UINT64 (AcpiGbl_XPm1aStatus.Address)));
300
301 LockFlags = AcpiOsAcquireLock (AcpiGbl_HardwareLock);
302
303 /* Clear the fixed events in PM1 A/B */
304
305 Status = AcpiHwRegisterWrite (ACPI_REGISTER_PM1_STATUS,
306 ACPI_BITMASK_ALL_FIXED_STATUS);
307 if (ACPI_FAILURE (Status))
308 {
309 goto UnlockAndExit;
310 }
311
312 /* Clear the GPE Bits in all GPE registers in all GPE blocks */
313
314 Status = AcpiEvWalkGpeList (AcpiHwClearGpeBlock, NULL);
315
316 UnlockAndExit:
317 AcpiOsReleaseLock (AcpiGbl_HardwareLock, LockFlags);
318 return_ACPI_STATUS (Status);
319 }
320
321
322 /*******************************************************************************
323 *
324 * FUNCTION: AcpiHwGetRegisterBitMask
325 *
326 * PARAMETERS: RegisterId - Index of ACPI Register to access
327 *
328 * RETURN: The bitmask to be used when accessing the register
329 *
330 * DESCRIPTION: Map RegisterId into a register bitmask.
331 *
332 ******************************************************************************/
333
334 ACPI_BIT_REGISTER_INFO *
335 AcpiHwGetBitRegisterInfo (
336 UINT32 RegisterId)
337 {
338 ACPI_FUNCTION_ENTRY ();
339
340
341 if (RegisterId > ACPI_BITREG_MAX)
342 {
343 ACPI_ERROR ((AE_INFO, "Invalid BitRegister ID: 0x%X", RegisterId));
344 return (NULL);
345 }
346
347 return (&AcpiGbl_BitRegisterInfo[RegisterId]);
348 }
349
350
351 /******************************************************************************
352 *
353 * FUNCTION: AcpiHwWritePm1Control
354 *
355 * PARAMETERS: Pm1aControl - Value to be written to PM1A control
356 * Pm1bControl - Value to be written to PM1B control
357 *
358 * RETURN: Status
359 *
360 * DESCRIPTION: Write the PM1 A/B control registers. These registers are
361 * different than than the PM1 A/B status and enable registers
362 * in that different values can be written to the A/B registers.
363 * Most notably, the SLP_TYP bits can be different, as per the
364 * values returned from the _Sx predefined methods.
365 *
366 ******************************************************************************/
367
368 ACPI_STATUS
369 AcpiHwWritePm1Control (
370 UINT32 Pm1aControl,
371 UINT32 Pm1bControl)
372 {
373 ACPI_STATUS Status;
374
375
376 ACPI_FUNCTION_TRACE (HwWritePm1Control);
377
378
379 Status = AcpiHwWrite (Pm1aControl, &AcpiGbl_FADT.XPm1aControlBlock);
380 if (ACPI_FAILURE (Status))
381 {
382 return_ACPI_STATUS (Status);
383 }
384
385 if (AcpiGbl_FADT.XPm1bControlBlock.Address)
386 {
387 Status = AcpiHwWrite (Pm1bControl, &AcpiGbl_FADT.XPm1bControlBlock);
388 }
389 return_ACPI_STATUS (Status);
390 }
391
392
393 /******************************************************************************
394 *
395 * FUNCTION: AcpiHwRegisterRead
396 *
397 * PARAMETERS: RegisterId - ACPI Register ID
398 * ReturnValue - Where the register value is returned
399 *
400 * RETURN: Status and the value read.
401 *
402 * DESCRIPTION: Read from the specified ACPI register
403 *
404 ******************************************************************************/
405
406 ACPI_STATUS
407 AcpiHwRegisterRead (
408 UINT32 RegisterId,
409 UINT32 *ReturnValue)
410 {
411 UINT32 Value = 0;
412 ACPI_STATUS Status;
413
414
415 ACPI_FUNCTION_TRACE (HwRegisterRead);
416
417
418 switch (RegisterId)
419 {
420 case ACPI_REGISTER_PM1_STATUS: /* PM1 A/B: 16-bit access each */
421
422 Status = AcpiHwReadMultiple (&Value,
423 &AcpiGbl_XPm1aStatus,
424 &AcpiGbl_XPm1bStatus);
425 break;
426
427
428 case ACPI_REGISTER_PM1_ENABLE: /* PM1 A/B: 16-bit access each */
429
430 Status = AcpiHwReadMultiple (&Value,
431 &AcpiGbl_XPm1aEnable,
432 &AcpiGbl_XPm1bEnable);
433 break;
434
435
436 case ACPI_REGISTER_PM1_CONTROL: /* PM1 A/B: 16-bit access each */
437
438 Status = AcpiHwReadMultiple (&Value,
439 &AcpiGbl_FADT.XPm1aControlBlock,
440 &AcpiGbl_FADT.XPm1bControlBlock);
441
442 /*
443 * Zero the write-only bits. From the ACPI specification, "Hardware
444 * Write-Only Bits": "Upon reads to registers with write-only bits,
445 * software masks out all write-only bits."
446 */
447 Value &= ~ACPI_PM1_CONTROL_WRITEONLY_BITS;
448 break;
449
450
451 case ACPI_REGISTER_PM2_CONTROL: /* 8-bit access */
452
453 Status = AcpiHwRead (&Value, &AcpiGbl_FADT.XPm2ControlBlock);
454 break;
455
456
457 case ACPI_REGISTER_PM_TIMER: /* 32-bit access */
458
459 Status = AcpiHwRead (&Value, &AcpiGbl_FADT.XPmTimerBlock);
460 break;
461
462
463 case ACPI_REGISTER_SMI_COMMAND_BLOCK: /* 8-bit access */
464
465 Status = AcpiHwReadPort (AcpiGbl_FADT.SmiCommand, &Value, 8);
466 break;
467
468
469 default:
470 ACPI_ERROR ((AE_INFO, "Unknown Register ID: 0x%X",
471 RegisterId));
472 Status = AE_BAD_PARAMETER;
473 break;
474 }
475
476 if (ACPI_SUCCESS (Status))
477 {
478 *ReturnValue = Value;
479 }
480
481 return_ACPI_STATUS (Status);
482 }
483
484
485 /******************************************************************************
486 *
487 * FUNCTION: AcpiHwRegisterWrite
488 *
489 * PARAMETERS: RegisterId - ACPI Register ID
490 * Value - The value to write
491 *
492 * RETURN: Status
493 *
494 * DESCRIPTION: Write to the specified ACPI register
495 *
496 * NOTE: In accordance with the ACPI specification, this function automatically
497 * preserves the value of the following bits, meaning that these bits cannot be
498 * changed via this interface:
499 *
500 * PM1_CONTROL[0] = SCI_EN
501 * PM1_CONTROL[9]
502 * PM1_STATUS[11]
503 *
504 * ACPI References:
505 * 1) Hardware Ignored Bits: When software writes to a register with ignored
506 * bit fields, it preserves the ignored bit fields
507 * 2) SCI_EN: OSPM always preserves this bit position
508 *
509 ******************************************************************************/
510
511 ACPI_STATUS
512 AcpiHwRegisterWrite (
513 UINT32 RegisterId,
514 UINT32 Value)
515 {
516 ACPI_STATUS Status;
517 UINT32 ReadValue;
518
519
520 ACPI_FUNCTION_TRACE (HwRegisterWrite);
521
522
523 switch (RegisterId)
524 {
525 case ACPI_REGISTER_PM1_STATUS: /* PM1 A/B: 16-bit access each */
526 /*
527 * Handle the "ignored" bit in PM1 Status. According to the ACPI
528 * specification, ignored bits are to be preserved when writing.
529 * Normally, this would mean a read/modify/write sequence. However,
530 * preserving a bit in the status register is different. Writing a
531 * one clears the status, and writing a zero preserves the status.
532 * Therefore, we must always write zero to the ignored bit.
533 *
534 * This behavior is clarified in the ACPI 4.0 specification.
535 */
536 Value &= ~ACPI_PM1_STATUS_PRESERVED_BITS;
537
538 Status = AcpiHwWriteMultiple (Value,
539 &AcpiGbl_XPm1aStatus,
540 &AcpiGbl_XPm1bStatus);
541 break;
542
543
544 case ACPI_REGISTER_PM1_ENABLE: /* PM1 A/B: 16-bit access each */
545
546 Status = AcpiHwWriteMultiple (Value,
547 &AcpiGbl_XPm1aEnable,
548 &AcpiGbl_XPm1bEnable);
549 break;
550
551
552 case ACPI_REGISTER_PM1_CONTROL: /* PM1 A/B: 16-bit access each */
553
554 /*
555 * Perform a read first to preserve certain bits (per ACPI spec)
556 * Note: This includes SCI_EN, we never want to change this bit
557 */
558 Status = AcpiHwReadMultiple (&ReadValue,
559 &AcpiGbl_FADT.XPm1aControlBlock,
560 &AcpiGbl_FADT.XPm1bControlBlock);
561 if (ACPI_FAILURE (Status))
562 {
563 goto Exit;
564 }
565
566 /* Insert the bits to be preserved */
567
568 ACPI_INSERT_BITS (Value, ACPI_PM1_CONTROL_PRESERVED_BITS, ReadValue);
569
570 /* Now we can write the data */
571
572 Status = AcpiHwWriteMultiple (Value,
573 &AcpiGbl_FADT.XPm1aControlBlock,
574 &AcpiGbl_FADT.XPm1bControlBlock);
575 break;
576
577
578 case ACPI_REGISTER_PM2_CONTROL: /* 8-bit access */
579
580 /*
581 * For control registers, all reserved bits must be preserved,
582 * as per the ACPI spec.
583 */
584 Status = AcpiHwRead (&ReadValue, &AcpiGbl_FADT.XPm2ControlBlock);
585 if (ACPI_FAILURE (Status))
586 {
587 goto Exit;
588 }
589
590 /* Insert the bits to be preserved */
591
592 ACPI_INSERT_BITS (Value, ACPI_PM2_CONTROL_PRESERVED_BITS, ReadValue);
593
594 Status = AcpiHwWrite (Value, &AcpiGbl_FADT.XPm2ControlBlock);
595 break;
596
597
598 case ACPI_REGISTER_PM_TIMER: /* 32-bit access */
599
600 Status = AcpiHwWrite (Value, &AcpiGbl_FADT.XPmTimerBlock);
601 break;
602
603
604 case ACPI_REGISTER_SMI_COMMAND_BLOCK: /* 8-bit access */
605
606 /* SMI_CMD is currently always in IO space */
607
608 Status = AcpiHwWritePort (AcpiGbl_FADT.SmiCommand, Value, 8);
609 break;
610
611
612 default:
613 ACPI_ERROR ((AE_INFO, "Unknown Register ID: 0x%X",
614 RegisterId));
615 Status = AE_BAD_PARAMETER;
616 break;
617 }
618
619 Exit:
620 return_ACPI_STATUS (Status);
621 }
622
623
624 /******************************************************************************
625 *
626 * FUNCTION: AcpiHwReadMultiple
627 *
628 * PARAMETERS: Value - Where the register value is returned
629 * RegisterA - First ACPI register (required)
630 * RegisterB - Second ACPI register (optional)
631 *
632 * RETURN: Status
633 *
634 * DESCRIPTION: Read from the specified two-part ACPI register (such as PM1 A/B)
635 *
636 ******************************************************************************/
637
638 static ACPI_STATUS
639 AcpiHwReadMultiple (
640 UINT32 *Value,
641 ACPI_GENERIC_ADDRESS *RegisterA,
642 ACPI_GENERIC_ADDRESS *RegisterB)
643 {
644 UINT32 ValueA = 0;
645 UINT32 ValueB = 0;
646 ACPI_STATUS Status;
647
648
649 /* The first register is always required */
650
651 Status = AcpiHwRead (&ValueA, RegisterA);
652 if (ACPI_FAILURE (Status))
653 {
654 return (Status);
655 }
656
657 /* Second register is optional */
658
659 if (RegisterB->Address)
660 {
661 Status = AcpiHwRead (&ValueB, RegisterB);
662 if (ACPI_FAILURE (Status))
663 {
664 return (Status);
665 }
666 }
667
668 /*
669 * OR the two return values together. No shifting or masking is necessary,
670 * because of how the PM1 registers are defined in the ACPI specification:
671 *
672 * "Although the bits can be split between the two register blocks (each
673 * register block has a unique pointer within the FADT), the bit positions
674 * are maintained. The register block with unimplemented bits (that is,
675 * those implemented in the other register block) always returns zeros,
676 * and writes have no side effects"
677 */
678 *Value = (ValueA | ValueB);
679 return (AE_OK);
680 }
681
682
683 /******************************************************************************
684 *
685 * FUNCTION: AcpiHwWriteMultiple
686 *
687 * PARAMETERS: Value - The value to write
688 * RegisterA - First ACPI register (required)
689 * RegisterB - Second ACPI register (optional)
690 *
691 * RETURN: Status
692 *
693 * DESCRIPTION: Write to the specified two-part ACPI register (such as PM1 A/B)
694 *
695 ******************************************************************************/
696
697 static ACPI_STATUS
698 AcpiHwWriteMultiple (
699 UINT32 Value,
700 ACPI_GENERIC_ADDRESS *RegisterA,
701 ACPI_GENERIC_ADDRESS *RegisterB)
702 {
703 ACPI_STATUS Status;
704
705
706 /* The first register is always required */
707
708 Status = AcpiHwWrite (Value, RegisterA);
709 if (ACPI_FAILURE (Status))
710 {
711 return (Status);
712 }
713
714 /*
715 * Second register is optional
716 *
717 * No bit shifting or clearing is necessary, because of how the PM1
718 * registers are defined in the ACPI specification:
719 *
720 * "Although the bits can be split between the two register blocks (each
721 * register block has a unique pointer within the FADT), the bit positions
722 * are maintained. The register block with unimplemented bits (that is,
723 * those implemented in the other register block) always returns zeros,
724 * and writes have no side effects"
725 */
726 if (RegisterB->Address)
727 {
728 Status = AcpiHwWrite (Value, RegisterB);
729 }
730
731 return (Status);
732 }
733