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acpi_util.c revision 1.19
      1 /*	$NetBSD: acpi_util.c,v 1.19 2020/10/23 10:59:37 jmcneill Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 2003, 2007 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Charles M. Hannum of By Noon Software, Inc.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 /*
     33  * Copyright 2001, 2003 Wasabi Systems, Inc.
     34  * All rights reserved.
     35  *
     36  * Written by Jason R. Thorpe for Wasabi Systems, Inc.
     37  *
     38  * Redistribution and use in source and binary forms, with or without
     39  * modification, are permitted provided that the following conditions
     40  * are met:
     41  * 1. Redistributions of source code must retain the above copyright
     42  *    notice, this list of conditions and the following disclaimer.
     43  * 2. Redistributions in binary form must reproduce the above copyright
     44  *    notice, this list of conditions and the following disclaimer in the
     45  *    documentation and/or other materials provided with the distribution.
     46  * 3. All advertising materials mentioning features or use of this software
     47  *    must display the following acknowledgement:
     48  *	This product includes software developed for the NetBSD Project by
     49  *	Wasabi Systems, Inc.
     50  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
     51  *    or promote products derived from this software without specific prior
     52  *    written permission.
     53  *
     54  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
     55  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     56  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     57  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
     58  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     59  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     60  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     61  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     62  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     63  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     64  * POSSIBILITY OF SUCH DAMAGE.
     65  */
     66 
     67 #include <sys/cdefs.h>
     68 __KERNEL_RCSID(0, "$NetBSD: acpi_util.c,v 1.19 2020/10/23 10:59:37 jmcneill Exp $");
     69 
     70 #include <sys/param.h>
     71 #include <sys/kmem.h>
     72 #include <sys/cpu.h>
     73 
     74 #include <dev/acpi/acpireg.h>
     75 #include <dev/acpi/acpivar.h>
     76 #include <dev/acpi/acpi_intr.h>
     77 
     78 #include <machine/acpi_machdep.h>
     79 
     80 #define _COMPONENT	ACPI_BUS_COMPONENT
     81 ACPI_MODULE_NAME	("acpi_util")
     82 
     83 static void		acpi_clean_node(ACPI_HANDLE, void *);
     84 
     85 static const char * const acpicpu_ids[] = {
     86 	"ACPI0007",
     87 	NULL
     88 };
     89 
     90 /*
     91  * Evaluate an integer object.
     92  */
     93 ACPI_STATUS
     94 acpi_eval_integer(ACPI_HANDLE handle, const char *path, ACPI_INTEGER *valp)
     95 {
     96 	ACPI_OBJECT obj;
     97 	ACPI_BUFFER buf;
     98 	ACPI_STATUS rv;
     99 
    100 	if (handle == NULL)
    101 		handle = ACPI_ROOT_OBJECT;
    102 
    103 	(void)memset(&obj, 0, sizeof(obj));
    104 	buf.Pointer = &obj;
    105 	buf.Length = sizeof(obj);
    106 
    107 	rv = AcpiEvaluateObject(handle, path, NULL, &buf);
    108 
    109 	if (ACPI_FAILURE(rv))
    110 		return rv;
    111 
    112 	/* Check that evaluation produced a return value. */
    113 	if (buf.Length == 0)
    114 		return AE_NULL_OBJECT;
    115 
    116 	if (obj.Type != ACPI_TYPE_INTEGER)
    117 		return AE_TYPE;
    118 
    119 	if (valp != NULL)
    120 		*valp = obj.Integer.Value;
    121 
    122 	return AE_OK;
    123 }
    124 
    125 /*
    126  * Evaluate an integer object with a single integer input parameter.
    127  */
    128 ACPI_STATUS
    129 acpi_eval_set_integer(ACPI_HANDLE handle, const char *path, ACPI_INTEGER val)
    130 {
    131 	ACPI_OBJECT_LIST arg;
    132 	ACPI_OBJECT obj;
    133 
    134 	if (handle == NULL)
    135 		handle = ACPI_ROOT_OBJECT;
    136 
    137 	obj.Type = ACPI_TYPE_INTEGER;
    138 	obj.Integer.Value = val;
    139 
    140 	arg.Count = 1;
    141 	arg.Pointer = &obj;
    142 
    143 	return AcpiEvaluateObject(handle, path, &arg, NULL);
    144 }
    145 
    146 /*
    147  * Evaluate a (Unicode) string object.
    148  */
    149 ACPI_STATUS
    150 acpi_eval_string(ACPI_HANDLE handle, const char *path, char **stringp)
    151 {
    152 	ACPI_OBJECT *obj;
    153 	ACPI_BUFFER buf;
    154 	ACPI_STATUS rv;
    155 
    156 	rv = acpi_eval_struct(handle, path, &buf);
    157 
    158 	if (ACPI_FAILURE(rv))
    159 		return rv;
    160 
    161 	obj = buf.Pointer;
    162 
    163 	if (obj->Type != ACPI_TYPE_STRING) {
    164 		rv = AE_TYPE;
    165 		goto out;
    166 	}
    167 
    168 	if (obj->String.Length == 0) {
    169 		rv = AE_BAD_DATA;
    170 		goto out;
    171 	}
    172 
    173 	*stringp = ACPI_ALLOCATE(obj->String.Length + 1);
    174 
    175 	if (*stringp == NULL) {
    176 		rv = AE_NO_MEMORY;
    177 		goto out;
    178 	}
    179 
    180 	(void)memcpy(*stringp, obj->String.Pointer, obj->String.Length);
    181 
    182 	(*stringp)[obj->String.Length] = '\0';
    183 
    184 out:
    185 	ACPI_FREE(buf.Pointer);
    186 
    187 	return rv;
    188 }
    189 
    190 /*
    191  * Evaluate a structure. Caller must free buf.Pointer by ACPI_FREE().
    192  */
    193 ACPI_STATUS
    194 acpi_eval_struct(ACPI_HANDLE handle, const char *path, ACPI_BUFFER *buf)
    195 {
    196 
    197 	if (handle == NULL)
    198 		handle = ACPI_ROOT_OBJECT;
    199 
    200 	buf->Pointer = NULL;
    201 	buf->Length = ACPI_ALLOCATE_LOCAL_BUFFER;
    202 
    203 	return AcpiEvaluateObject(handle, path, NULL, buf);
    204 }
    205 
    206 /*
    207  * Evaluate a reference handle from an element in a package.
    208  */
    209 ACPI_STATUS
    210 acpi_eval_reference_handle(ACPI_OBJECT *elm, ACPI_HANDLE *handle)
    211 {
    212 
    213 	if (elm == NULL || handle == NULL)
    214 		return AE_BAD_PARAMETER;
    215 
    216 	switch (elm->Type) {
    217 
    218 	case ACPI_TYPE_ANY:
    219 	case ACPI_TYPE_LOCAL_REFERENCE:
    220 
    221 		if (elm->Reference.Handle == NULL)
    222 			return AE_NULL_ENTRY;
    223 
    224 		*handle = elm->Reference.Handle;
    225 
    226 		return AE_OK;
    227 
    228 	case ACPI_TYPE_STRING:
    229 		return AcpiGetHandle(NULL, elm->String.Pointer, handle);
    230 
    231 	default:
    232 		return AE_TYPE;
    233 	}
    234 }
    235 
    236 /*
    237  * Iterate over all objects in a package, and pass them all
    238  * to a function. If the called function returns non-AE_OK,
    239  * the iteration is stopped and that value is returned.
    240  */
    241 ACPI_STATUS
    242 acpi_foreach_package_object(ACPI_OBJECT *pkg,
    243     ACPI_STATUS (*func)(ACPI_OBJECT *, void *), void *arg)
    244 {
    245 	ACPI_STATUS rv = AE_OK;
    246 	uint32_t i;
    247 
    248 	if (pkg == NULL)
    249 		return AE_BAD_PARAMETER;
    250 
    251 	if (pkg->Type != ACPI_TYPE_PACKAGE)
    252 		return AE_TYPE;
    253 
    254 	for (i = 0; i < pkg->Package.Count; i++) {
    255 
    256 		rv = (*func)(&pkg->Package.Elements[i], arg);
    257 
    258 		if (ACPI_FAILURE(rv))
    259 			break;
    260 	}
    261 
    262 	return rv;
    263 }
    264 
    265 /*
    266  * Fetch data info the specified (empty) ACPI buffer.
    267  * Caller must free buf.Pointer by ACPI_FREE().
    268  */
    269 ACPI_STATUS
    270 acpi_get(ACPI_HANDLE handle, ACPI_BUFFER *buf,
    271     ACPI_STATUS (*getit)(ACPI_HANDLE, ACPI_BUFFER *))
    272 {
    273 
    274 	buf->Pointer = NULL;
    275 	buf->Length = ACPI_ALLOCATE_LOCAL_BUFFER;
    276 
    277 	return (*getit)(handle, buf);
    278 }
    279 
    280 /*
    281  * Return a complete pathname from a handle.
    282  *
    283  * Note that the function uses static data storage;
    284  * if the data is needed for future use, it should be
    285  * copied before any subsequent calls overwrite it.
    286  */
    287 const char *
    288 acpi_name(ACPI_HANDLE handle)
    289 {
    290 	static char name[80];
    291 	ACPI_BUFFER buf;
    292 	ACPI_STATUS rv;
    293 
    294 	if (handle == NULL)
    295 		handle = ACPI_ROOT_OBJECT;
    296 
    297 	buf.Pointer = name;
    298 	buf.Length = sizeof(name);
    299 
    300 	rv = AcpiGetName(handle, ACPI_FULL_PATHNAME, &buf);
    301 
    302 	if (ACPI_FAILURE(rv))
    303 		return "UNKNOWN";
    304 
    305 	return name;
    306 }
    307 
    308 /*
    309  * Match given IDs against _HID and _CIDs.
    310  */
    311 int
    312 acpi_match_hid(ACPI_DEVICE_INFO *ad, const char * const *ids)
    313 {
    314 	uint32_t i, n;
    315 	char *id;
    316 
    317 	while (*ids) {
    318 
    319 		if ((ad->Valid & ACPI_VALID_HID) != 0) {
    320 
    321 			if (pmatch(ad->HardwareId.String, *ids, NULL) == 2)
    322 				return 1;
    323 		}
    324 
    325 		if ((ad->Valid & ACPI_VALID_CID) != 0) {
    326 
    327 			n = ad->CompatibleIdList.Count;
    328 
    329 			for (i = 0; i < n; i++) {
    330 
    331 				id = ad->CompatibleIdList.Ids[i].String;
    332 
    333 				if (pmatch(id, *ids, NULL) == 2)
    334 					return 1;
    335 			}
    336 		}
    337 
    338 		ids++;
    339 	}
    340 
    341 	return 0;
    342 }
    343 
    344 /*
    345  * Match a PCI-defined bass-class, sub-class, and programming interface
    346  * against a handle's _CLS object.
    347  */
    348 int
    349 acpi_match_class(ACPI_HANDLE handle, uint8_t pci_class, uint8_t pci_subclass,
    350     uint8_t pci_interface)
    351 {
    352 	ACPI_BUFFER buf;
    353 	ACPI_OBJECT *obj;
    354 	ACPI_STATUS rv;
    355 	int match = 0;
    356 
    357 	rv = acpi_eval_struct(handle, "_CLS", &buf);
    358 	if (ACPI_FAILURE(rv))
    359 		goto done;
    360 
    361 	obj = buf.Pointer;
    362 	if (obj->Type != ACPI_TYPE_PACKAGE)
    363 		goto done;
    364 	if (obj->Package.Count != 3)
    365 		goto done;
    366 	if (obj->Package.Elements[0].Type != ACPI_TYPE_INTEGER ||
    367 	    obj->Package.Elements[1].Type != ACPI_TYPE_INTEGER ||
    368 	    obj->Package.Elements[2].Type != ACPI_TYPE_INTEGER)
    369 		goto done;
    370 
    371 	match = obj->Package.Elements[0].Integer.Value == pci_class &&
    372 		obj->Package.Elements[1].Integer.Value == pci_subclass &&
    373 		obj->Package.Elements[2].Integer.Value == pci_interface;
    374 
    375 done:
    376 	if (buf.Pointer)
    377 		ACPI_FREE(buf.Pointer);
    378 	return match;
    379 }
    380 
    381 /*
    382  * Match a device node from a handle.
    383  */
    384 struct acpi_devnode *
    385 acpi_match_node(ACPI_HANDLE handle)
    386 {
    387 	struct acpi_devnode *ad;
    388 	ACPI_STATUS rv;
    389 
    390 	if (handle == NULL)
    391 		return NULL;
    392 
    393 	rv = AcpiGetData(handle, acpi_clean_node, (void **)&ad);
    394 
    395 	if (ACPI_FAILURE(rv))
    396 		return NULL;
    397 
    398 	return ad;
    399 }
    400 
    401 /*
    402  * Permanently associate a device node with a handle.
    403  */
    404 void
    405 acpi_match_node_init(struct acpi_devnode *ad)
    406 {
    407 	(void)AcpiAttachData(ad->ad_handle, acpi_clean_node, ad);
    408 }
    409 
    410 static void
    411 acpi_clean_node(ACPI_HANDLE handle, void *aux)
    412 {
    413 	/* Nothing. */
    414 }
    415 
    416 /*
    417  * Match a handle from a cpu_info. Returns NULL on failure.
    418  *
    419  * Note that acpi_match_node() can be used if the device node
    420  * is also required.
    421  */
    422 ACPI_HANDLE
    423 acpi_match_cpu_info(struct cpu_info *ci)
    424 {
    425 	struct acpi_softc *sc = acpi_softc;
    426 	struct acpi_devnode *ad;
    427 	ACPI_INTEGER val;
    428 	ACPI_OBJECT *obj;
    429 	ACPI_BUFFER buf;
    430 	ACPI_HANDLE hdl;
    431 	ACPI_STATUS rv;
    432 
    433 	if (sc == NULL || acpi_active == 0)
    434 		return NULL;
    435 
    436 	/*
    437 	 * CPUs are declared in the ACPI namespace
    438 	 * either as a Processor() or as a Device().
    439 	 * In both cases the MADT entries are used
    440 	 * for the match (see ACPI 4.0, section 8.4).
    441 	 */
    442 	SIMPLEQ_FOREACH(ad, &sc->ad_head, ad_list) {
    443 
    444 		hdl = ad->ad_handle;
    445 
    446 		switch (ad->ad_type) {
    447 
    448 		case ACPI_TYPE_DEVICE:
    449 
    450 			if (acpi_match_hid(ad->ad_devinfo, acpicpu_ids) == 0)
    451 				break;
    452 
    453 			rv = acpi_eval_integer(hdl, "_UID", &val);
    454 
    455 			if (ACPI_SUCCESS(rv) && val == ci->ci_acpiid)
    456 				return hdl;
    457 
    458 			break;
    459 
    460 		case ACPI_TYPE_PROCESSOR:
    461 
    462 			rv = acpi_eval_struct(hdl, NULL, &buf);
    463 
    464 			if (ACPI_FAILURE(rv))
    465 				break;
    466 
    467 			obj = buf.Pointer;
    468 
    469 			if (obj->Processor.ProcId == ci->ci_acpiid) {
    470 				ACPI_FREE(buf.Pointer);
    471 				return hdl;
    472 			}
    473 
    474 			ACPI_FREE(buf.Pointer);
    475 			break;
    476 		}
    477 	}
    478 
    479 	return NULL;
    480 }
    481 
    482 /*
    483  * Match a CPU from a handle. Returns NULL on failure.
    484  */
    485 struct cpu_info *
    486 acpi_match_cpu_handle(ACPI_HANDLE hdl)
    487 {
    488 	struct cpu_info *ci;
    489 	ACPI_DEVICE_INFO *di;
    490 	CPU_INFO_ITERATOR cii;
    491 	ACPI_INTEGER val;
    492 	ACPI_OBJECT *obj;
    493 	ACPI_BUFFER buf;
    494 	ACPI_STATUS rv;
    495 
    496 	ci = NULL;
    497 	di = NULL;
    498 	buf.Pointer = NULL;
    499 
    500 	rv = AcpiGetObjectInfo(hdl, &di);
    501 
    502 	if (ACPI_FAILURE(rv))
    503 		return NULL;
    504 
    505 	switch (di->Type) {
    506 
    507 	case ACPI_TYPE_DEVICE:
    508 
    509 		if (acpi_match_hid(di, acpicpu_ids) == 0)
    510 			goto out;
    511 
    512 		rv = acpi_eval_integer(hdl, "_UID", &val);
    513 
    514 		if (ACPI_FAILURE(rv))
    515 			goto out;
    516 
    517 		break;
    518 
    519 	case ACPI_TYPE_PROCESSOR:
    520 
    521 		rv = acpi_eval_struct(hdl, NULL, &buf);
    522 
    523 		if (ACPI_FAILURE(rv))
    524 			goto out;
    525 
    526 		obj = buf.Pointer;
    527 		val = obj->Processor.ProcId;
    528 		break;
    529 
    530 	default:
    531 		goto out;
    532 	}
    533 
    534 	for (CPU_INFO_FOREACH(cii, ci)) {
    535 
    536 		if (ci->ci_acpiid == val)
    537 			goto out;
    538 	}
    539 
    540 	ci = NULL;
    541 
    542 out:
    543 	if (di != NULL)
    544 		ACPI_FREE(di);
    545 
    546 	if (buf.Pointer != NULL)
    547 		ACPI_FREE(buf.Pointer);
    548 
    549 	return ci;
    550 }
    551 
    552 struct acpi_irq_handler {
    553 	uint32_t aih_irq;
    554 	void *aih_ih;
    555 };
    556 
    557 void *
    558 acpi_intr_establish(device_t dev, uint64_t c, int ipl, bool mpsafe,
    559     int (*intr)(void *), void *iarg, const char *xname)
    560 {
    561 	ACPI_STATUS rv;
    562 	ACPI_HANDLE hdl = (void *)(uintptr_t)c;
    563 	struct acpi_resources res;
    564 	struct acpi_irq *irq;
    565 	void *aih = NULL;
    566 
    567 	rv = acpi_resource_parse(dev, hdl, "_CRS", &res,
    568 	    &acpi_resource_parse_ops_quiet);
    569 	if (ACPI_FAILURE(rv))
    570 		return NULL;
    571 
    572 	irq = acpi_res_irq(&res, 0);
    573 	if (irq == NULL)
    574 		goto end;
    575 
    576 	aih = acpi_intr_establish_irq(dev, irq, ipl, mpsafe,
    577 	    intr, iarg, xname);
    578 
    579 end:
    580 	acpi_resource_cleanup(&res);
    581 
    582 	return aih;
    583 }
    584 
    585 void *
    586 acpi_intr_establish_irq(device_t dev, struct acpi_irq *irq, int ipl,
    587     bool mpsafe, int (*intr)(void *), void *iarg, const char *xname)
    588 {
    589 	struct acpi_irq_handler *aih;
    590 	void *ih;
    591 
    592 	const int type = (irq->ar_type == ACPI_EDGE_SENSITIVE) ? IST_EDGE : IST_LEVEL;
    593 	ih = acpi_md_intr_establish(irq->ar_irq, ipl, type, intr, iarg, mpsafe, xname);
    594 	if (ih == NULL)
    595 		return NULL;
    596 
    597 	aih = kmem_alloc(sizeof(struct acpi_irq_handler), KM_SLEEP);
    598 	aih->aih_irq = irq->ar_irq;
    599 	aih->aih_ih = ih;
    600 
    601 	return aih;
    602 }
    603 
    604 void
    605 acpi_intr_mask(void *c)
    606 {
    607 	struct acpi_irq_handler * const aih = c;
    608 
    609 	acpi_md_intr_mask(aih->aih_ih);
    610 }
    611 
    612 void
    613 acpi_intr_unmask(void *c)
    614 {
    615 	struct acpi_irq_handler * const aih = c;
    616 
    617 	acpi_md_intr_unmask(aih->aih_ih);
    618 }
    619 
    620 void
    621 acpi_intr_disestablish(void *c)
    622 {
    623 	struct acpi_irq_handler *aih = c;
    624 
    625 	acpi_md_intr_disestablish(aih->aih_ih);
    626 	kmem_free(aih, sizeof(struct acpi_irq_handler));
    627 }
    628 
    629 const char *
    630 acpi_intr_string(void *c, char *buf, size_t size)
    631 {
    632 	struct acpi_irq_handler *aih = c;
    633 	intr_handle_t ih = aih->aih_irq;
    634 
    635 	return intr_string(ih, buf, size);
    636 }
    637 
    638 /*
    639  * USB Device-Specific Data (_DSD) support
    640  */
    641 
    642 static UINT8 acpi_dsd_uuid[ACPI_UUID_LENGTH] = {
    643 	0x14, 0xd8, 0xff, 0xda, 0xba, 0x6e, 0x8c, 0x4d,
    644 	0x8a, 0x91, 0xbc, 0x9b, 0xbf, 0x4a, 0xa3, 0x01
    645 };
    646 
    647 static ACPI_STATUS
    648 acpi_dsd_property(ACPI_HANDLE handle, const char *prop, ACPI_BUFFER *pbuf, ACPI_OBJECT_TYPE type, ACPI_OBJECT **ret)
    649 {
    650 	ACPI_OBJECT *obj, *uuid, *props, *pobj, *propkey, *propval;
    651 	ACPI_STATUS rv;
    652 	int n;
    653 
    654 	rv = AcpiEvaluateObjectTyped(handle, "_DSD", NULL, pbuf, ACPI_TYPE_PACKAGE);
    655 	if (ACPI_FAILURE(rv))
    656 		return rv;
    657 
    658 	props = NULL;
    659 	obj = (ACPI_OBJECT *)pbuf->Pointer;
    660 	for (n = 0; (n + 1) < obj->Package.Count; n += 2) {
    661 		uuid = &obj->Package.Elements[n];
    662 		if (uuid->Buffer.Length == ACPI_UUID_LENGTH &&
    663 		    memcmp(uuid->Buffer.Pointer, acpi_dsd_uuid, ACPI_UUID_LENGTH) == 0) {
    664 			props = &obj->Package.Elements[n + 1];
    665 			break;
    666 		}
    667 	}
    668 	if (props == NULL)
    669 		return AE_NOT_FOUND;
    670 
    671 	for (n = 0; n < props->Package.Count; n++) {
    672 		pobj = &props->Package.Elements[n];
    673 		if (pobj->Type != ACPI_TYPE_PACKAGE || pobj->Package.Count != 2)
    674 			continue;
    675 		propkey = (ACPI_OBJECT *)&pobj->Package.Elements[0];
    676 		propval = (ACPI_OBJECT *)&pobj->Package.Elements[1];
    677 		if (propkey->Type != ACPI_TYPE_STRING)
    678 			continue;
    679 		if (strcmp(propkey->String.Pointer, prop) != 0)
    680 			continue;
    681 
    682 		if (propval->Type != type) {
    683 			return AE_TYPE;
    684 		} else {
    685 			*ret = propval;
    686 			return AE_OK;
    687 		}
    688 		break;
    689 	}
    690 
    691 	return AE_NOT_FOUND;
    692 }
    693 
    694 ACPI_STATUS
    695 acpi_dsd_integer(ACPI_HANDLE handle, const char *prop, ACPI_INTEGER *val)
    696 {
    697 	ACPI_OBJECT *propval;
    698 	ACPI_STATUS rv;
    699 	ACPI_BUFFER buf;
    700 
    701 	buf.Pointer = NULL;
    702 	buf.Length = ACPI_ALLOCATE_BUFFER;
    703 
    704 	rv = acpi_dsd_property(handle, prop, &buf, ACPI_TYPE_INTEGER, &propval);
    705 	if (ACPI_SUCCESS(rv))
    706 		*val = propval->Integer.Value;
    707 
    708 	if (buf.Pointer != NULL)
    709 		ACPI_FREE(buf.Pointer);
    710 	return rv;
    711 }
    712 
    713 ACPI_STATUS
    714 acpi_dsd_string(ACPI_HANDLE handle, const char *prop, char **val)
    715 {
    716 	ACPI_OBJECT *propval;
    717 	ACPI_STATUS rv;
    718 	ACPI_BUFFER buf;
    719 
    720 	buf.Pointer = NULL;
    721 	buf.Length = ACPI_ALLOCATE_BUFFER;
    722 
    723 	rv = acpi_dsd_property(handle, prop, &buf, ACPI_TYPE_STRING, &propval);
    724 	if (ACPI_SUCCESS(rv))
    725 		*val = kmem_strdup(propval->String.Pointer, KM_SLEEP);
    726 
    727 	if (buf.Pointer != NULL)
    728 		ACPI_FREE(buf.Pointer);
    729 	return rv;
    730 }
    731