acpi_pci_machdep.c revision 1.14 1 /* $NetBSD: acpi_pci_machdep.c,v 1.14 2020/01/23 11:59:37 jmcneill Exp $ */
2
3 /*-
4 * Copyright (c) 2018 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jared McNeill <jmcneill (at) invisible.ca>.
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 #define _INTR_PRIVATE
33
34 #include <sys/cdefs.h>
35 __KERNEL_RCSID(0, "$NetBSD: acpi_pci_machdep.c,v 1.14 2020/01/23 11:59:37 jmcneill Exp $");
36
37 #include <sys/param.h>
38 #include <sys/bus.h>
39 #include <sys/device.h>
40 #include <sys/intr.h>
41 #include <sys/systm.h>
42 #include <sys/kernel.h>
43 #include <sys/extent.h>
44 #include <sys/queue.h>
45 #include <sys/mutex.h>
46 #include <sys/kmem.h>
47
48 #include <machine/cpu.h>
49
50 #include <arm/cpufunc.h>
51
52 #include <arm/pic/picvar.h>
53
54 #include <dev/pci/pcireg.h>
55 #include <dev/pci/pcivar.h>
56 #include <dev/pci/pciconf.h>
57
58 #include <dev/acpi/acpivar.h>
59 #include <dev/acpi/acpi_mcfg.h>
60 #include <dev/acpi/acpi_pci.h>
61
62 #include <arm/acpi/acpi_iort.h>
63 #include <arm/acpi/acpi_pci_machdep.h>
64
65 #include <arm/pci/pci_msi_machdep.h>
66
67 struct acpi_pci_prt {
68 u_int prt_segment;
69 u_int prt_bus;
70 ACPI_HANDLE prt_handle;
71 TAILQ_ENTRY(acpi_pci_prt) prt_list;
72 };
73
74 static TAILQ_HEAD(, acpi_pci_prt) acpi_pci_irq_routes =
75 TAILQ_HEAD_INITIALIZER(acpi_pci_irq_routes);
76
77 struct acpi_pci_pct {
78 struct acpi_pci_context pct_ap;
79 TAILQ_ENTRY(acpi_pci_pct) pct_list;
80 };
81
82 static TAILQ_HEAD(, acpi_pci_pct) acpi_pci_chipset_tags =
83 TAILQ_HEAD_INITIALIZER(acpi_pci_chipset_tags);
84
85 struct acpi_pci_intr;
86
87 struct acpi_pci_intr {
88 struct pic_softc pi_pic;
89 int pi_irqbase;
90 int pi_irq;
91 uint32_t pi_unblocked;
92 void *pi_ih;
93 TAILQ_ENTRY(acpi_pci_intr) pi_list;
94 };
95
96 static TAILQ_HEAD(, acpi_pci_intr) acpi_pci_intrs =
97 TAILQ_HEAD_INITIALIZER(acpi_pci_intrs);
98
99 static const struct acpi_pci_quirk acpi_pci_quirks[] = {
100 /* OEM ID OEM Table ID Revision Seg Func */
101 { "AMAZON", "GRAVITON", 0, -1, acpi_pci_graviton_init },
102 { "ARMLTD", "ARMN1SDP", 0x20181101, 0, acpi_pci_n1sdp_init },
103 { "ARMLTD", "ARMN1SDP", 0x20181101, 1, acpi_pci_n1sdp_init },
104 };
105
106 pci_chipset_tag_t acpi_pci_md_get_chipset_tag(struct acpi_softc *, int, int);
107
108 static void acpi_pci_md_attach_hook(device_t, device_t,
109 struct pcibus_attach_args *);
110 static int acpi_pci_md_bus_maxdevs(void *, int);
111 static pcitag_t acpi_pci_md_make_tag(void *, int, int, int);
112 static void acpi_pci_md_decompose_tag(void *, pcitag_t, int *, int *, int *);
113 static u_int acpi_pci_md_get_segment(void *);
114 static uint32_t acpi_pci_md_get_devid(void *, uint32_t);
115 static pcireg_t acpi_pci_md_conf_read(void *, pcitag_t, int);
116 static void acpi_pci_md_conf_write(void *, pcitag_t, int, pcireg_t);
117 static int acpi_pci_md_conf_hook(void *, int, int, int, pcireg_t);
118 static void acpi_pci_md_conf_interrupt(void *, int, int, int, int, int *);
119
120 static int acpi_pci_md_intr_map(const struct pci_attach_args *,
121 pci_intr_handle_t *);
122 static const char *acpi_pci_md_intr_string(void *, pci_intr_handle_t,
123 char *, size_t);
124 static const struct evcnt *acpi_pci_md_intr_evcnt(void *, pci_intr_handle_t);
125 static int acpi_pci_md_intr_setattr(void *, pci_intr_handle_t *, int,
126 uint64_t);
127 static void * acpi_pci_md_intr_establish(void *, pci_intr_handle_t,
128 int, int (*)(void *), void *,
129 const char *);
130 static void acpi_pci_md_intr_disestablish(void *, void *);
131
132 struct arm32_pci_chipset arm_acpi_pci_chipset = {
133 .pc_attach_hook = acpi_pci_md_attach_hook,
134 .pc_bus_maxdevs = acpi_pci_md_bus_maxdevs,
135 .pc_make_tag = acpi_pci_md_make_tag,
136 .pc_decompose_tag = acpi_pci_md_decompose_tag,
137 .pc_get_segment = acpi_pci_md_get_segment,
138 .pc_get_devid = acpi_pci_md_get_devid,
139 .pc_conf_read = acpi_pci_md_conf_read,
140 .pc_conf_write = acpi_pci_md_conf_write,
141 .pc_conf_hook = acpi_pci_md_conf_hook,
142 .pc_conf_interrupt = acpi_pci_md_conf_interrupt,
143
144 .pc_intr_map = acpi_pci_md_intr_map,
145 .pc_intr_string = acpi_pci_md_intr_string,
146 .pc_intr_evcnt = acpi_pci_md_intr_evcnt,
147 .pc_intr_setattr = acpi_pci_md_intr_setattr,
148 .pc_intr_establish = acpi_pci_md_intr_establish,
149 .pc_intr_disestablish = acpi_pci_md_intr_disestablish,
150 };
151
152 static ACPI_STATUS
153 acpi_pci_md_pci_link(ACPI_HANDLE handle, pci_chipset_tag_t pc, int bus)
154 {
155 ACPI_PCI_ROUTING_TABLE *prt;
156 ACPI_HANDLE linksrc;
157 ACPI_BUFFER buf;
158 ACPI_STATUS rv;
159 void *linkdev;
160
161 rv = acpi_get(handle, &buf, AcpiGetIrqRoutingTable);
162 if (ACPI_FAILURE(rv))
163 return rv;
164
165 for (char *p = buf.Pointer; ; p += prt->Length) {
166 prt = (ACPI_PCI_ROUTING_TABLE *)p;
167 if (prt->Length == 0)
168 break;
169
170 const u_int dev = ACPI_HIWORD(prt->Address);
171 if (prt->Source[0] != 0) {
172 aprint_debug("ACPI: %s dev %u INT%c on lnkdev %s\n",
173 acpi_name(handle), dev, 'A' + (prt->Pin & 3), prt->Source);
174 rv = AcpiGetHandle(ACPI_ROOT_OBJECT, prt->Source, &linksrc);
175 if (ACPI_FAILURE(rv)) {
176 aprint_debug("ACPI: AcpiGetHandle failed for '%s': %s\n",
177 prt->Source, AcpiFormatException(rv));
178 continue;
179 }
180
181 linkdev = acpi_pci_link_devbyhandle(linksrc);
182 acpi_pci_link_add_reference(linkdev, pc, 0, bus, dev, prt->Pin & 3);
183 } else {
184 aprint_debug("ACPI: %s dev %u INT%c on globint %d\n",
185 acpi_name(handle), dev, 'A' + (prt->Pin & 3), prt->SourceIndex);
186 }
187 }
188
189 return AE_OK;
190 }
191
192 static void
193 acpi_pci_md_attach_hook(device_t parent, device_t self,
194 struct pcibus_attach_args *pba)
195 {
196 struct acpi_pci_context *ap = pba->pba_pc->pc_conf_v;
197 struct acpi_pci_prt *prt, *prtp;
198 struct acpi_devnode *ad;
199 ACPI_HANDLE handle;
200 int seg, bus, dev, func;
201
202 seg = ap->ap_seg;
203 handle = NULL;
204
205 if (pba->pba_bridgetag) {
206 /*
207 * Find the PCI address of our parent bridge and look for the
208 * corresponding ACPI device node. If there is no node for this
209 * bus, use the parent bridge routing information.
210 */
211 acpi_pci_md_decompose_tag(NULL, *pba->pba_bridgetag, &bus, &dev, &func);
212 ad = acpi_pcidev_find(seg, bus, dev, func);
213 if (ad != NULL) {
214 handle = ad->ad_handle;
215 } else {
216 /* No routes defined for this bus, copy from parent */
217 TAILQ_FOREACH(prtp, &acpi_pci_irq_routes, prt_list)
218 if (prtp->prt_bus == bus) {
219 handle = prtp->prt_handle;
220 break;
221 }
222 }
223 } else {
224 /*
225 * Lookup the ACPI device node for the root bus.
226 */
227 ad = acpi_pciroot_find(seg, 0);
228 if (ad != NULL)
229 handle = ad->ad_handle;
230 }
231
232 if (handle != NULL) {
233 prt = kmem_alloc(sizeof(*prt), KM_SLEEP);
234 prt->prt_bus = pba->pba_bus;
235 prt->prt_segment = ap->ap_seg;
236 prt->prt_handle = handle;
237 TAILQ_INSERT_TAIL(&acpi_pci_irq_routes, prt, prt_list);
238 }
239
240 acpimcfg_map_bus(self, pba->pba_pc, pba->pba_bus);
241
242 if (ad != NULL) {
243 /*
244 * This is a new ACPI managed bus. Add PCI link references.
245 */
246 acpi_pci_md_pci_link(ad->ad_handle, pba->pba_pc, pba->pba_bus);
247 }
248 }
249
250 static int
251 acpi_pci_md_bus_maxdevs(void *v, int busno)
252 {
253 return 32;
254 }
255
256 static pcitag_t
257 acpi_pci_md_make_tag(void *v, int b, int d, int f)
258 {
259 return (b << 16) | (d << 11) | (f << 8);
260 }
261
262 static void
263 acpi_pci_md_decompose_tag(void *v, pcitag_t tag, int *bp, int *dp, int *fp)
264 {
265 if (bp)
266 *bp = (tag >> 16) & 0xff;
267 if (dp)
268 *dp = (tag >> 11) & 0x1f;
269 if (fp)
270 *fp = (tag >> 8) & 0x7;
271 }
272
273 static u_int
274 acpi_pci_md_get_segment(void *v)
275 {
276 struct acpi_pci_context * const ap = v;
277
278 return ap->ap_seg;
279 }
280
281 static uint32_t
282 acpi_pci_md_get_devid(void *v, uint32_t devid)
283 {
284 struct acpi_pci_context * const ap = v;
285
286 return acpi_iort_pci_root_map(ap->ap_seg, devid);
287 }
288
289 static pcireg_t
290 acpi_pci_md_conf_read(void *v, pcitag_t tag, int offset)
291 {
292 struct acpi_pci_context * const ap = v;
293 pcireg_t val;
294
295 if (offset < 0 || offset >= PCI_EXTCONF_SIZE)
296 return (pcireg_t) -1;
297
298 if (ap->ap_conf_read != NULL)
299 ap->ap_conf_read(&ap->ap_pc, tag, offset, &val);
300 else
301 acpimcfg_conf_read(&ap->ap_pc, tag, offset, &val);
302
303 return val;
304 }
305
306 static void
307 acpi_pci_md_conf_write(void *v, pcitag_t tag, int offset, pcireg_t val)
308 {
309 struct acpi_pci_context * const ap = v;
310
311 if (offset < 0 || offset >= PCI_EXTCONF_SIZE)
312 return;
313
314 if (ap->ap_conf_write != NULL)
315 ap->ap_conf_write(&ap->ap_pc, tag, offset, val);
316 else
317 acpimcfg_conf_write(&ap->ap_pc, tag, offset, val);
318 }
319
320 static int
321 acpi_pci_md_conf_hook(void *v, int b, int d, int f, pcireg_t id)
322 {
323 return PCI_CONF_DEFAULT;
324 }
325
326 static void
327 acpi_pci_md_conf_interrupt(void *v, int bus, int dev, int ipin, int sqiz, int *ilinep)
328 {
329 }
330
331 static struct acpi_pci_prt *
332 acpi_pci_md_intr_find_prt(pci_chipset_tag_t pc, u_int bus)
333 {
334 struct acpi_pci_prt *prt, *prtp;
335 u_int segment;
336
337 segment = pci_get_segment(pc);
338
339 prt = NULL;
340 TAILQ_FOREACH(prtp, &acpi_pci_irq_routes, prt_list)
341 if (prtp->prt_segment == segment && prtp->prt_bus == bus) {
342 prt = prtp;
343 break;
344 }
345
346 return prt;
347 }
348
349 static int
350 acpi_pci_md_intr_map(const struct pci_attach_args *pa, pci_intr_handle_t *ih)
351 {
352 struct acpi_pci_prt *prt;
353 ACPI_PCI_ROUTING_TABLE *tab;
354 int line, pol, trig, error;
355 ACPI_HANDLE linksrc;
356 ACPI_BUFFER buf;
357 void *linkdev;
358
359 if (pa->pa_intrpin == PCI_INTERRUPT_PIN_NONE)
360 return EINVAL;
361
362 prt = acpi_pci_md_intr_find_prt(pa->pa_pc, pa->pa_bus);
363 if (prt == NULL)
364 return ENXIO;
365
366 if (ACPI_FAILURE(acpi_get(prt->prt_handle, &buf, AcpiGetIrqRoutingTable)))
367 return EIO;
368
369 error = ENOENT;
370 for (char *p = buf.Pointer; ; p += tab->Length) {
371 tab = (ACPI_PCI_ROUTING_TABLE *)p;
372 if (tab->Length == 0)
373 break;
374
375 if (pa->pa_device == ACPI_HIWORD(tab->Address) &&
376 (pa->pa_intrpin - 1) == (tab->Pin & 3)) {
377 if (tab->Source[0] != 0) {
378 if (ACPI_FAILURE(AcpiGetHandle(ACPI_ROOT_OBJECT, tab->Source, &linksrc)))
379 goto done;
380 linkdev = acpi_pci_link_devbyhandle(linksrc);
381 *ih = acpi_pci_link_route_interrupt(linkdev,
382 pa->pa_pc, tab->SourceIndex,
383 &line, &pol, &trig);
384 error = 0;
385 goto done;
386 } else {
387 *ih = tab->SourceIndex;
388 error = 0;
389 goto done;
390 }
391 }
392 }
393
394 done:
395 ACPI_FREE(buf.Pointer);
396 return error;
397 }
398
399 static const char *
400 acpi_pci_md_intr_string(void *v, pci_intr_handle_t ih, char *buf, size_t len)
401 {
402 const int irq = __SHIFTOUT(ih, ARM_PCI_INTR_IRQ);
403 const int vec = __SHIFTOUT(ih, ARM_PCI_INTR_MSI_VEC);
404
405 if (ih & ARM_PCI_INTR_MSIX)
406 snprintf(buf, len, "irq %d (MSI-X vec %d)", irq, vec);
407 else if (ih & ARM_PCI_INTR_MSI)
408 snprintf(buf, len, "irq %d (MSI vec %d)", irq, vec);
409 else
410 snprintf(buf, len, "irq %d", irq);
411
412 return buf;
413 }
414
415 static const struct evcnt *
416 acpi_pci_md_intr_evcnt(void *v, pci_intr_handle_t ih)
417 {
418 return NULL;
419 }
420
421 static int
422 acpi_pci_md_intr_setattr(void *v, pci_intr_handle_t *ih, int attr, uint64_t data)
423 {
424 switch (attr) {
425 case PCI_INTR_MPSAFE:
426 if (data)
427 *ih |= ARM_PCI_INTR_MPSAFE;
428 else
429 *ih &= ~ARM_PCI_INTR_MPSAFE;
430 return 0;
431 default:
432 return ENODEV;
433 }
434 }
435
436 static struct acpi_pci_intr *
437 acpi_pci_md_intr_lookup(int irq)
438 {
439 struct acpi_pci_intr *pi;
440
441 TAILQ_FOREACH(pi, &acpi_pci_intrs, pi_list)
442 if (pi->pi_irq == irq)
443 return pi;
444
445 return NULL;
446 }
447
448 static void
449 acpi_pci_md_unblock_irqs(struct pic_softc *pic, size_t irqbase, uint32_t irqmask)
450 {
451 struct acpi_pci_intr * const pi = (struct acpi_pci_intr *)pic;
452
453 pi->pi_unblocked |= irqmask;
454 }
455
456 static void
457 acpi_pci_md_block_irqs(struct pic_softc *pic, size_t irqbase, uint32_t irqmask)
458 {
459 struct acpi_pci_intr * const pi = (struct acpi_pci_intr *)pic;
460
461 pi->pi_unblocked &= ~irqmask;
462 }
463
464 static int
465 acpi_pci_md_find_pending_irqs(struct pic_softc *pic)
466 {
467 struct acpi_pci_intr * const pi = (struct acpi_pci_intr *)pic;
468
469 pic_mark_pending_sources(pic, 0, pi->pi_unblocked);
470
471 return 1;
472 }
473
474 static void
475 acpi_pci_md_establish_irq(struct pic_softc *pic, struct intrsource *is)
476 {
477 }
478
479 static void
480 acpi_pci_md_source_name(struct pic_softc *pic, int irq, char *buf, size_t len)
481 {
482 snprintf(buf, len, "slot %d", irq);
483 }
484
485 static struct pic_ops acpi_pci_pic_ops = {
486 .pic_unblock_irqs = acpi_pci_md_unblock_irqs,
487 .pic_block_irqs = acpi_pci_md_block_irqs,
488 .pic_find_pending_irqs = acpi_pci_md_find_pending_irqs,
489 .pic_establish_irq = acpi_pci_md_establish_irq,
490 .pic_source_name = acpi_pci_md_source_name,
491 };
492
493 static void *
494 acpi_pci_md_intr_establish(void *v, pci_intr_handle_t ih, int ipl,
495 int (*callback)(void *), void *arg, const char *xname)
496 {
497 struct acpi_pci_context * const ap = v;
498 struct acpi_pci_intr *pi;
499 int slot;
500
501 if ((ih & (ARM_PCI_INTR_MSI | ARM_PCI_INTR_MSIX)) != 0)
502 return arm_pci_msi_intr_establish(&ap->ap_pc, ih, ipl, callback, arg, xname);
503
504 const int irq = (int)__SHIFTOUT(ih, ARM_PCI_INTR_IRQ);
505 const int mpsafe = (ih & ARM_PCI_INTR_MPSAFE) ? IST_MPSAFE : 0;
506
507 pi = acpi_pci_md_intr_lookup(irq);
508 if (pi == NULL) {
509 pi = kmem_zalloc(sizeof(*pi), KM_SLEEP);
510 pi->pi_irq = irq;
511 snprintf(pi->pi_pic.pic_name, sizeof(pi->pi_pic.pic_name),
512 "PCI irq %d", irq);
513 pi->pi_pic.pic_maxsources = 32;
514 pi->pi_pic.pic_ops = &acpi_pci_pic_ops;
515 pi->pi_irqbase = pic_add(&pi->pi_pic, PIC_IRQBASE_ALLOC);
516 TAILQ_INSERT_TAIL(&acpi_pci_intrs, pi, pi_list);
517 pi->pi_ih = intr_establish_xname(irq, IPL_SCHED, IST_LEVEL | IST_MPSAFE,
518 pic_handle_intr, &pi->pi_pic, device_xname(ap->ap_dev));
519 }
520 if (pi->pi_ih == NULL)
521 return NULL;
522
523 /* Find a free slot */
524 for (slot = 0; slot < pi->pi_pic.pic_maxsources; slot++)
525 if (pi->pi_pic.pic_sources[slot] == NULL)
526 break;
527 if (slot == pi->pi_pic.pic_maxsources)
528 return NULL;
529
530 return intr_establish_xname(pi->pi_irqbase + slot, ipl, IST_LEVEL | mpsafe,
531 callback, arg, xname);
532 }
533
534 static void
535 acpi_pci_md_intr_disestablish(void *v, void *vih)
536 {
537 intr_disestablish(vih);
538 }
539
540 const struct acpi_pci_quirk *
541 acpi_pci_md_find_quirk(int seg)
542 {
543 ACPI_STATUS rv;
544 ACPI_TABLE_MCFG *mcfg;
545 u_int n;
546
547 rv = AcpiGetTable(ACPI_SIG_MCFG, 0, (ACPI_TABLE_HEADER **)&mcfg);
548 if (ACPI_FAILURE(rv))
549 return NULL;
550
551 for (n = 0; n < __arraycount(acpi_pci_quirks); n++) {
552 const struct acpi_pci_quirk *q = &acpi_pci_quirks[n];
553 if (memcmp(q->q_oemid, mcfg->Header.OemId, ACPI_OEM_ID_SIZE) == 0 &&
554 memcmp(q->q_oemtableid, mcfg->Header.OemTableId, ACPI_OEM_TABLE_ID_SIZE) == 0 &&
555 q->q_oemrevision == mcfg->Header.OemRevision &&
556 (q->q_segment == -1 || q->q_segment == seg))
557 return q;
558 }
559
560 return NULL;
561 }
562
563 pci_chipset_tag_t
564 acpi_pci_md_get_chipset_tag(struct acpi_softc *sc, int seg, int bbn)
565 {
566 struct acpi_pci_pct *pct = NULL, *pctp;
567 const struct acpi_pci_quirk *q;
568
569 TAILQ_FOREACH(pctp, &acpi_pci_chipset_tags, pct_list)
570 if (pctp->pct_ap.ap_seg == seg) {
571 pct = pctp;
572 break;
573 }
574
575 if (pct == NULL) {
576 pct = kmem_zalloc(sizeof(*pct), KM_SLEEP);
577 pct->pct_ap.ap_dev = sc->sc_dev;
578 pct->pct_ap.ap_pc = arm_acpi_pci_chipset;
579 pct->pct_ap.ap_pc.pc_conf_v = &pct->pct_ap;
580 pct->pct_ap.ap_pc.pc_intr_v = &pct->pct_ap;
581 pct->pct_ap.ap_seg = seg;
582 pct->pct_ap.ap_bus = bbn;
583 pct->pct_ap.ap_bst = acpi_softc->sc_memt;
584
585 q = acpi_pci_md_find_quirk(seg);
586 if (q != NULL)
587 q->q_init(&pct->pct_ap);
588
589 TAILQ_INSERT_TAIL(&acpi_pci_chipset_tags, pct, pct_list);
590 }
591
592 return &pct->pct_ap.ap_pc;
593 }
594 __strong_alias(acpi_get_pci_chipset_tag,acpi_pci_md_get_chipset_tag);
595