xref: /netbsd-src/sys/dev/pci/pci.c (revision fc046893c76cd6c3dc855c29b23ef4b6bff46880)
1 /*	$NetBSD: pci.c,v 1.159 2021/04/24 23:36:57 thorpej Exp $	*/
2 
3 /*
4  * Copyright (c) 1995, 1996, 1997, 1998
5  *     Christopher G. Demetriou.  All rights reserved.
6  * Copyright (c) 1994 Charles M. Hannum.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by Charles M. Hannum.
19  * 4. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 /*
35  * PCI bus autoconfiguration.
36  */
37 
38 #include <sys/cdefs.h>
39 __KERNEL_RCSID(0, "$NetBSD: pci.c,v 1.159 2021/04/24 23:36:57 thorpej Exp $");
40 
41 #ifdef _KERNEL_OPT
42 #include "opt_pci.h"
43 #endif
44 
45 #include <sys/param.h>
46 #include <sys/malloc.h>
47 #include <sys/systm.h>
48 #include <sys/device.h>
49 #include <sys/module.h>
50 
51 #include <dev/pci/pcireg.h>
52 #include <dev/pci/pcivar.h>
53 #include <dev/pci/pcidevs.h>
54 #include <dev/pci/ppbvar.h>
55 
56 #include <net/if.h>
57 
58 #include "locators.h"
59 
60 static bool pci_child_register(device_t);
61 
62 #ifdef PCI_CONFIG_DUMP
63 int pci_config_dump = 1;
64 #else
65 int pci_config_dump = 0;
66 #endif
67 
68 int	pciprint(void *, const char *);
69 
70 #ifdef PCI_MACHDEP_ENUMERATE_BUS
71 #define pci_enumerate_bus PCI_MACHDEP_ENUMERATE_BUS
72 #endif
73 
74 /*
75  * Important note about PCI-ISA bridges:
76  *
77  * Callbacks are used to configure these devices so that ISA/EISA bridges
78  * can attach their child busses after PCI configuration is done.
79  *
80  * This works because:
81  *	(1) there can be at most one ISA/EISA bridge per PCI bus, and
82  *	(2) any ISA/EISA bridges must be attached to primary PCI
83  *	    busses (i.e. bus zero).
84  *
85  * That boils down to: there can only be one of these outstanding
86  * at a time, it is cleared when configuring PCI bus 0 before any
87  * subdevices have been found, and it is run after all subdevices
88  * of PCI bus 0 have been found.
89  *
90  * This is needed because there are some (legacy) PCI devices which
91  * can show up as ISA/EISA devices as well (the prime example of which
92  * are VGA controllers).  If you attach ISA from a PCI-ISA/EISA bridge,
93  * and the bridge is seen before the video board is, the board can show
94  * up as an ISA device, and that can (bogusly) complicate the PCI device's
95  * attach code, or make the PCI device not be properly attached at all.
96  *
97  * We use the generic config_defer() facility to achieve this.
98  */
99 
100 int
101 pcirescan(device_t self, const char *ifattr, const int *locators)
102 {
103 	struct pci_softc *sc = device_private(self);
104 
105 	KASSERT(ifattr && !strcmp(ifattr, "pci"));
106 	KASSERT(locators);
107 
108 	pci_enumerate_bus(sc, locators, NULL, NULL);
109 
110 	return 0;
111 }
112 
113 int
114 pcimatch(device_t parent, cfdata_t cf, void *aux)
115 {
116 	struct pcibus_attach_args *pba = aux;
117 
118 	/* Check the locators */
119 	if (cf->cf_loc[PCIBUSCF_BUS] != PCIBUSCF_BUS_DEFAULT &&
120 	    cf->cf_loc[PCIBUSCF_BUS] != pba->pba_bus)
121 		return 0;
122 
123 	/* sanity */
124 	if (pba->pba_bus < 0 || pba->pba_bus > 255)
125 		return 0;
126 
127 	/*
128 	 * XXX check other (hardware?) indicators
129 	 */
130 
131 	return 1;
132 }
133 
134 void
135 pciattach(device_t parent, device_t self, void *aux)
136 {
137 	struct pcibus_attach_args *pba = aux;
138 	struct pci_softc *sc = device_private(self);
139 	int io_enabled, mem_enabled, mrl_enabled, mrm_enabled, mwi_enabled;
140 	const char *sep = "";
141 	static const int wildcard[PCICF_NLOCS] = {
142 		PCICF_DEV_DEFAULT, PCICF_FUNCTION_DEFAULT
143 	};
144 
145 	sc->sc_dev = self;
146 
147 	pci_attach_hook(parent, self, pba);
148 
149 	aprint_naive("\n");
150 	aprint_normal("\n");
151 
152 	io_enabled = (pba->pba_flags & PCI_FLAGS_IO_OKAY);
153 	mem_enabled = (pba->pba_flags & PCI_FLAGS_MEM_OKAY);
154 	mrl_enabled = (pba->pba_flags & PCI_FLAGS_MRL_OKAY);
155 	mrm_enabled = (pba->pba_flags & PCI_FLAGS_MRM_OKAY);
156 	mwi_enabled = (pba->pba_flags & PCI_FLAGS_MWI_OKAY);
157 
158 	if (io_enabled == 0 && mem_enabled == 0) {
159 		aprint_error_dev(self, "no spaces enabled!\n");
160 		goto fail;
161 	}
162 
163 #define	PRINT(str)							\
164 do {									\
165 	aprint_verbose("%s%s", sep, str);				\
166 	sep = ", ";							\
167 } while (/*CONSTCOND*/0)
168 
169 	aprint_verbose_dev(self, "");
170 
171 	if (io_enabled)
172 		PRINT("i/o space");
173 	if (mem_enabled)
174 		PRINT("memory space");
175 	aprint_verbose(" enabled");
176 
177 	if (mrl_enabled || mrm_enabled || mwi_enabled) {
178 		if (mrl_enabled)
179 			PRINT("rd/line");
180 		if (mrm_enabled)
181 			PRINT("rd/mult");
182 		if (mwi_enabled)
183 			PRINT("wr/inv");
184 		aprint_verbose(" ok");
185 	}
186 
187 	aprint_verbose("\n");
188 
189 #undef PRINT
190 
191 	sc->sc_iot = pba->pba_iot;
192 	sc->sc_memt = pba->pba_memt;
193 	sc->sc_dmat = pba->pba_dmat;
194 	sc->sc_dmat64 = pba->pba_dmat64;
195 	sc->sc_pc = pba->pba_pc;
196 	sc->sc_bus = pba->pba_bus;
197 	sc->sc_bridgetag = pba->pba_bridgetag;
198 	sc->sc_maxndevs = pci_bus_maxdevs(pba->pba_pc, pba->pba_bus);
199 	sc->sc_intrswiz = pba->pba_intrswiz;
200 	sc->sc_intrtag = pba->pba_intrtag;
201 	sc->sc_flags = pba->pba_flags;
202 
203 	device_pmf_driver_set_child_register(sc->sc_dev, pci_child_register);
204 
205 	pcirescan(sc->sc_dev, "pci", wildcard);
206 
207 fail:
208 	if (!pmf_device_register(self, NULL, NULL))
209 		aprint_error_dev(self, "couldn't establish power handler\n");
210 }
211 
212 int
213 pcidetach(device_t self, int flags)
214 {
215 	int rc;
216 
217 	if ((rc = config_detach_children(self, flags)) != 0)
218 		return rc;
219 	pmf_device_deregister(self);
220 	return 0;
221 }
222 
223 int
224 pciprint(void *aux, const char *pnp)
225 {
226 	struct pci_attach_args *pa = aux;
227 	char devinfo[256];
228 	const struct pci_quirkdata *qd;
229 
230 	if (pnp) {
231 		pci_devinfo(pa->pa_id, pa->pa_class, 1, devinfo, sizeof(devinfo));
232 		aprint_normal("%s at %s", devinfo, pnp);
233 	}
234 	aprint_normal(" dev %d function %d", pa->pa_device, pa->pa_function);
235 	if (pci_config_dump) {
236 		printf(": ");
237 		pci_conf_print(pa->pa_pc, pa->pa_tag, NULL);
238 		if (!pnp)
239 			pci_devinfo(pa->pa_id, pa->pa_class, 1, devinfo, sizeof(devinfo));
240 		printf("%s at %s", devinfo, pnp ? pnp : "?");
241 		printf(" dev %d function %d (", pa->pa_device, pa->pa_function);
242 #ifdef __i386__
243 		printf("tag %#lx, intrtag %#lx, intrswiz %#lx, intrpin %#lx",
244 		    *(long *)&pa->pa_tag, *(long *)&pa->pa_intrtag,
245 		    (long)pa->pa_intrswiz, (long)pa->pa_intrpin);
246 #else
247 		printf("intrswiz %#lx, intrpin %#lx",
248 		    (long)pa->pa_intrswiz, (long)pa->pa_intrpin);
249 #endif
250 		printf(", i/o %s, mem %s,",
251 		    pa->pa_flags & PCI_FLAGS_IO_OKAY ? "on" : "off",
252 		    pa->pa_flags & PCI_FLAGS_MEM_OKAY ? "on" : "off");
253 		qd = pci_lookup_quirkdata(PCI_VENDOR(pa->pa_id),
254 		    PCI_PRODUCT(pa->pa_id));
255 		if (qd == NULL) {
256 			printf(" no quirks");
257 		} else {
258 			snprintb(devinfo, sizeof (devinfo),
259 			    "\002\001multifn\002singlefn\003skipfunc0"
260 			    "\004skipfunc1\005skipfunc2\006skipfunc3"
261 			    "\007skipfunc4\010skipfunc5\011skipfunc6"
262 			    "\012skipfunc7", qd->quirks);
263 			printf(" quirks %s", devinfo);
264 		}
265 		printf(")");
266 	}
267 	return UNCONF;
268 }
269 
270 int
271 pci_probe_device(struct pci_softc *sc, pcitag_t tag,
272     int (*match)(const struct pci_attach_args *),
273     struct pci_attach_args *pap)
274 {
275 	pci_chipset_tag_t pc = sc->sc_pc;
276 	struct pci_attach_args pa;
277 	pcireg_t id, /* csr, */ pciclass, intr, bhlcr, bar, endbar;
278 #ifdef __HAVE_PCI_MSI_MSIX
279 	pcireg_t cap;
280 	int off;
281 #endif
282 	int ret, pin, bus, device, function, i, width;
283 	int locs[PCICF_NLOCS];
284 
285 	pci_decompose_tag(pc, tag, &bus, &device, &function);
286 
287 	/* a driver already attached? */
288 	if (sc->PCI_SC_DEVICESC(device, function).c_dev != NULL && !match)
289 		return 0;
290 
291 	id = pci_conf_read(pc, tag, PCI_ID_REG);
292 
293 	/* Invalid vendor ID value? */
294 	if (PCI_VENDOR(id) == PCI_VENDOR_INVALID)
295 		return 0;
296 	/* XXX Not invalid, but we've done this ~forever. */
297 	if (PCI_VENDOR(id) == 0)
298 		return 0;
299 
300 	bhlcr = pci_conf_read(pc, tag, PCI_BHLC_REG);
301 	if (PCI_HDRTYPE_TYPE(bhlcr) > 2)
302 		return 0;
303 
304 	/* csr = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG); */
305 	pciclass = pci_conf_read(pc, tag, PCI_CLASS_REG);
306 
307 	/* Collect memory range info */
308 	memset(sc->PCI_SC_DEVICESC(device, function).c_range, 0,
309 	    sizeof(sc->PCI_SC_DEVICESC(device, function).c_range));
310 	i = 0;
311 	switch (PCI_HDRTYPE_TYPE(bhlcr)) {
312 	case PCI_HDRTYPE_PPB:
313 		endbar = PCI_MAPREG_PPB_END;
314 		break;
315 	case PCI_HDRTYPE_PCB:
316 		endbar = PCI_MAPREG_PCB_END;
317 		break;
318 	default:
319 		endbar = PCI_MAPREG_END;
320 		break;
321 	}
322 	for (bar = PCI_MAPREG_START; bar < endbar; bar += width) {
323 		struct pci_range *r;
324 		pcireg_t type;
325 
326 		width = 4;
327 		if (pci_mapreg_probe(pc, tag, bar, &type) == 0)
328 			continue;
329 
330 		if (PCI_MAPREG_TYPE(type) == PCI_MAPREG_TYPE_MEM) {
331 			if (PCI_MAPREG_MEM_TYPE(type) ==
332 			    PCI_MAPREG_MEM_TYPE_64BIT)
333 				width = 8;
334 
335 			r = &sc->PCI_SC_DEVICESC(device, function).c_range[i++];
336 			if (pci_mapreg_info(pc, tag, bar, type,
337 			    &r->r_offset, &r->r_size, &r->r_flags) != 0)
338 				break;
339 			if ((PCI_VENDOR(id) == PCI_VENDOR_ATI) && (bar == 0x10)
340 			    && (r->r_size == 0x1000000)) {
341 				struct pci_range *nr;
342 				/*
343 				 * this has to be a mach64
344 				 * split things up so each half-aperture can
345 				 * be mapped PREFETCHABLE except the last page
346 				 * which may contain registers
347 				 */
348 				r->r_size = 0x7ff000;
349 				r->r_flags = BUS_SPACE_MAP_LINEAR |
350 					     BUS_SPACE_MAP_PREFETCHABLE;
351 				nr = &sc->PCI_SC_DEVICESC(device,
352 				    function).c_range[i++];
353 				nr->r_offset = r->r_offset + 0x800000;
354 				nr->r_size = 0x7ff000;
355 				nr->r_flags = BUS_SPACE_MAP_LINEAR |
356 					      BUS_SPACE_MAP_PREFETCHABLE;
357 			} else if ((PCI_VENDOR(id) == PCI_VENDOR_SILMOTION) &&
358 			   (PCI_PRODUCT(id) == PCI_PRODUCT_SILMOTION_SM502) &&
359 			   (bar == 0x10)) {
360 			   	r->r_flags = BUS_SPACE_MAP_LINEAR |
361 					     BUS_SPACE_MAP_PREFETCHABLE;
362 			}
363 		}
364 	}
365 
366 	pa.pa_iot = sc->sc_iot;
367 	pa.pa_memt = sc->sc_memt;
368 	pa.pa_dmat = sc->sc_dmat;
369 	pa.pa_dmat64 = sc->sc_dmat64;
370 	pa.pa_pc = pc;
371 	pa.pa_bus = bus;
372 	pa.pa_device = device;
373 	pa.pa_function = function;
374 	pa.pa_tag = tag;
375 	pa.pa_id = id;
376 	pa.pa_class = pciclass;
377 
378 	/*
379 	 * Set up memory, I/O enable, and PCI command flags
380 	 * as appropriate.
381 	 */
382 	pa.pa_flags = sc->sc_flags;
383 
384 	/*
385 	 * If the cache line size is not configured, then
386 	 * clear the MRL/MRM/MWI command-ok flags.
387 	 */
388 	if (PCI_CACHELINE(bhlcr) == 0) {
389 		pa.pa_flags &= ~(PCI_FLAGS_MRL_OKAY|
390 		    PCI_FLAGS_MRM_OKAY|PCI_FLAGS_MWI_OKAY);
391 	}
392 
393 	if (sc->sc_bridgetag == NULL) {
394 		pa.pa_intrswiz = 0;
395 		pa.pa_intrtag = tag;
396 	} else {
397 		pa.pa_intrswiz = sc->sc_intrswiz + device;
398 		pa.pa_intrtag = sc->sc_intrtag;
399 	}
400 
401 	intr = pci_conf_read(pc, tag, PCI_INTERRUPT_REG);
402 
403 	pin = PCI_INTERRUPT_PIN(intr);
404 	pa.pa_rawintrpin = pin;
405 	if (pin == PCI_INTERRUPT_PIN_NONE) {
406 		/* no interrupt */
407 		pa.pa_intrpin = 0;
408 	} else {
409 		/*
410 		 * swizzle it based on the number of busses we're
411 		 * behind and our device number.
412 		 */
413 		pa.pa_intrpin = 	/* XXX */
414 		    ((pin + pa.pa_intrswiz - 1) % 4) + 1;
415 	}
416 	pa.pa_intrline = PCI_INTERRUPT_LINE(intr);
417 
418 #ifdef __HAVE_PCI_MSI_MSIX
419 	if (pci_get_ht_capability(pc, tag, PCI_HT_CAP_MSIMAP, &off, &cap)) {
420 		/*
421 		 * XXX Should we enable MSI mapping ourselves on
422 		 * systems that have it disabled?
423 		 */
424 		if (cap & PCI_HT_MSI_ENABLED) {
425 			uint64_t addr;
426 			if ((cap & PCI_HT_MSI_FIXED) == 0) {
427 				addr = pci_conf_read(pc, tag,
428 				    off + PCI_HT_MSI_ADDR_LO);
429 				addr |= (uint64_t)pci_conf_read(pc, tag,
430 				    off + PCI_HT_MSI_ADDR_HI) << 32;
431 			} else
432 				addr = PCI_HT_MSI_FIXED_ADDR;
433 
434 			/*
435 			 * XXX This will fail to enable MSI on systems
436 			 * that don't use the canonical address.
437 			 */
438 			if (addr == PCI_HT_MSI_FIXED_ADDR) {
439 				pa.pa_flags |= PCI_FLAGS_MSI_OKAY;
440 				pa.pa_flags |= PCI_FLAGS_MSIX_OKAY;
441 			} else
442 				aprint_verbose_dev(sc->sc_dev,
443 				    "HyperTransport MSI mapping is not supported yet. Disable MSI/MSI-X.\n");
444 		}
445 	}
446 #endif
447 
448 	if (match != NULL) {
449 		ret = (*match)(&pa);
450 		if (ret != 0 && pap != NULL)
451 			*pap = pa;
452 	} else {
453 		struct pci_child *c;
454 		locs[PCICF_DEV] = device;
455 		locs[PCICF_FUNCTION] = function;
456 
457 		c = &sc->PCI_SC_DEVICESC(device, function);
458 		pci_conf_capture(pc, tag, &c->c_conf);
459 		if (pci_get_powerstate(pc, tag, &c->c_powerstate) == 0)
460 			c->c_psok = true;
461 		else
462 			c->c_psok = false;
463 
464 		c->c_dev = config_found(sc->sc_dev, &pa, pciprint,
465 		    CFARG_SUBMATCH, config_stdsubmatch,
466 		    CFARG_LOCATORS, locs,
467 		    CFARG_EOL);
468 
469 		ret = (c->c_dev != NULL);
470 	}
471 
472 	return ret;
473 }
474 
475 void
476 pcidevdetached(device_t self, device_t child)
477 {
478 	struct pci_softc *sc = device_private(self);
479 	int d, f;
480 	pcitag_t tag;
481 	struct pci_child *c;
482 
483 	d = device_locator(child, PCICF_DEV);
484 	f = device_locator(child, PCICF_FUNCTION);
485 
486 	c = &sc->PCI_SC_DEVICESC(d, f);
487 
488 	KASSERT(c->c_dev == child);
489 
490 	tag = pci_make_tag(sc->sc_pc, sc->sc_bus, d, f);
491 	if (c->c_psok)
492 		pci_set_powerstate(sc->sc_pc, tag, c->c_powerstate);
493 	pci_conf_restore(sc->sc_pc, tag, &c->c_conf);
494 	c->c_dev = NULL;
495 }
496 
497 CFATTACH_DECL3_NEW(pci, sizeof(struct pci_softc),
498     pcimatch, pciattach, pcidetach, NULL, pcirescan, pcidevdetached,
499     DVF_DETACH_SHUTDOWN);
500 
501 int
502 pci_get_capability(pci_chipset_tag_t pc, pcitag_t tag, int capid,
503     int *offset, pcireg_t *value)
504 {
505 	pcireg_t reg;
506 	unsigned int ofs;
507 
508 	reg = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
509 	if (!(reg & PCI_STATUS_CAPLIST_SUPPORT))
510 		return 0;
511 
512 	/* Determine the Capability List Pointer register to start with. */
513 	reg = pci_conf_read(pc, tag, PCI_BHLC_REG);
514 	switch (PCI_HDRTYPE_TYPE(reg)) {
515 	case 0:	/* standard device header */
516 	case 1: /* PCI-PCI bridge header */
517 		ofs = PCI_CAPLISTPTR_REG;
518 		break;
519 	case 2:	/* PCI-CardBus Bridge header */
520 		ofs = PCI_CARDBUS_CAPLISTPTR_REG;
521 		break;
522 	default:
523 		return 0;
524 	}
525 
526 	ofs = PCI_CAPLIST_PTR(pci_conf_read(pc, tag, ofs));
527 	while (ofs != 0) {
528 		if ((ofs & 3) || (ofs < 0x40)) {
529 			int bus, device, function;
530 
531 			pci_decompose_tag(pc, tag, &bus, &device, &function);
532 
533 			printf("Skipping broken PCI header on %d:%d:%d\n",
534 			    bus, device, function);
535 			break;
536 		}
537 		reg = pci_conf_read(pc, tag, ofs);
538 		if (PCI_CAPLIST_CAP(reg) == capid) {
539 			if (offset)
540 				*offset = ofs;
541 			if (value)
542 				*value = reg;
543 			return 1;
544 		}
545 		ofs = PCI_CAPLIST_NEXT(reg);
546 	}
547 
548 	return 0;
549 }
550 
551 int
552 pci_get_ht_capability(pci_chipset_tag_t pc, pcitag_t tag, int capid,
553     int *offset, pcireg_t *value)
554 {
555 	pcireg_t reg;
556 	unsigned int ofs;
557 
558 	if (pci_get_capability(pc, tag, PCI_CAP_LDT, &ofs, NULL) == 0)
559 		return 0;
560 
561 	while (ofs != 0) {
562 #ifdef DIAGNOSTIC
563 		if ((ofs & 3) || (ofs < 0x40))
564 			panic("pci_get_ht_capability");
565 #endif
566 		reg = pci_conf_read(pc, tag, ofs);
567 		if (PCI_HT_CAP(reg) == capid) {
568 			if (offset)
569 				*offset = ofs;
570 			if (value)
571 				*value = reg;
572 			return 1;
573 		}
574 		ofs = PCI_CAPLIST_NEXT(reg);
575 	}
576 
577 	return 0;
578 }
579 
580 /*
581  * return number of the devices's MSI vectors
582  * return 0 if the device does not support MSI
583  */
584 int
585 pci_msi_count(pci_chipset_tag_t pc, pcitag_t tag)
586 {
587 	pcireg_t reg;
588 	uint32_t mmc;
589 	int count, offset;
590 
591 	if (pci_get_capability(pc, tag, PCI_CAP_MSI, &offset, NULL) == 0)
592 		return 0;
593 
594 	reg = pci_conf_read(pc, tag, offset + PCI_MSI_CTL);
595 	mmc = PCI_MSI_CTL_MMC(reg);
596 	count = 1 << mmc;
597 	if (count > PCI_MSI_MAX_VECTORS) {
598 		aprint_error("detect an illegal device! The device use reserved MMC values.\n");
599 		return 0;
600 	}
601 
602 	return count;
603 }
604 
605 /*
606  * return number of the devices's MSI-X vectors
607  * return 0 if the device does not support MSI-X
608  */
609 int
610 pci_msix_count(pci_chipset_tag_t pc, pcitag_t tag)
611 {
612 	pcireg_t reg;
613 	int offset;
614 
615 	if (pci_get_capability(pc, tag, PCI_CAP_MSIX, &offset, NULL) == 0)
616 		return 0;
617 
618 	reg = pci_conf_read(pc, tag, offset + PCI_MSIX_CTL);
619 
620 	return PCI_MSIX_CTL_TBLSIZE(reg);
621 }
622 
623 int
624 pci_get_ext_capability(pci_chipset_tag_t pc, pcitag_t tag, int capid,
625     int *offset, pcireg_t *value)
626 {
627 	pcireg_t reg;
628 	unsigned int ofs;
629 
630 	/* Only supported for PCI-express devices */
631 	if (!pci_get_capability(pc, tag, PCI_CAP_PCIEXPRESS, NULL, NULL))
632 		return 0;
633 
634 	ofs = PCI_EXTCAPLIST_BASE;
635 	reg = pci_conf_read(pc, tag, ofs);
636 	if (reg == 0xffffffff || reg == 0)
637 		return 0;
638 
639 	for (;;) {
640 #ifdef DIAGNOSTIC
641 		if ((ofs & 3) || ofs < PCI_EXTCAPLIST_BASE)
642 			panic("%s: invalid offset %u", __func__, ofs);
643 #endif
644 		if (PCI_EXTCAPLIST_CAP(reg) == capid) {
645 			if (offset != NULL)
646 				*offset = ofs;
647 			if (value != NULL)
648 				*value = reg;
649 			return 1;
650 		}
651 		ofs = PCI_EXTCAPLIST_NEXT(reg);
652 		if (ofs == 0)
653 			break;
654 		reg = pci_conf_read(pc, tag, ofs);
655 	}
656 
657 	return 0;
658 }
659 
660 int
661 pci_find_device(struct pci_attach_args *pa,
662 		int (*match)(const struct pci_attach_args *))
663 {
664 	extern struct cfdriver pci_cd;
665 	device_t pcidev;
666 	int i;
667 	static const int wildcard[2] = {
668 		PCICF_DEV_DEFAULT,
669 		PCICF_FUNCTION_DEFAULT
670 	};
671 
672 	for (i = 0; i < pci_cd.cd_ndevs; i++) {
673 		pcidev = device_lookup(&pci_cd, i);
674 		if (pcidev != NULL &&
675 		    pci_enumerate_bus(device_private(pcidev), wildcard,
676 		    		      match, pa) != 0)
677 			return 1;
678 	}
679 	return 0;
680 }
681 
682 #ifndef PCI_MACHDEP_ENUMERATE_BUS
683 /*
684  * Generic PCI bus enumeration routine.  Used unless machine-dependent
685  * code needs to provide something else.
686  */
687 int
688 pci_enumerate_bus(struct pci_softc *sc, const int *locators,
689     int (*match)(const struct pci_attach_args *), struct pci_attach_args *pap)
690 {
691 	pci_chipset_tag_t pc = sc->sc_pc;
692 	int device, function, nfunctions, ret;
693 	const struct pci_quirkdata *qd;
694 	pcireg_t id, bhlcr;
695 	pcitag_t tag;
696 	uint8_t devs[32];
697 	int i, n;
698 
699 	device_t bridgedev;
700 	bool arien = false;
701 	bool downstream_port = false;
702 
703 	/* Check PCIe ARI and port type */
704 	bridgedev = device_parent(sc->sc_dev);
705 	if (device_is_a(bridgedev, "ppb")) {
706 		struct ppb_softc *ppbsc = device_private(bridgedev);
707 		pci_chipset_tag_t ppbpc = ppbsc->sc_pc;
708 		pcitag_t ppbtag = ppbsc->sc_tag;
709 		pcireg_t pciecap, capreg, reg;
710 
711 		if (pci_get_capability(ppbpc, ppbtag, PCI_CAP_PCIEXPRESS,
712 		    &pciecap, &capreg) != 0) {
713 			switch (PCIE_XCAP_TYPE(capreg)) {
714 			case PCIE_XCAP_TYPE_ROOT:
715 			case PCIE_XCAP_TYPE_DOWN:
716 			case PCIE_XCAP_TYPE_PCI2PCIE:
717 				downstream_port = true;
718 				break;
719 			}
720 
721 			reg = pci_conf_read(ppbpc, ppbtag, pciecap
722 			    + PCIE_DCSR2);
723 			if ((reg & PCIE_DCSR2_ARI_FWD) != 0)
724 				arien = true;
725 		}
726 	}
727 
728 	n = pci_bus_devorder(sc->sc_pc, sc->sc_bus, devs, __arraycount(devs));
729 	if (downstream_port) {
730 		/* PCIe downstream ports only have a single child device */
731 		n = 1;
732 	}
733 
734 	for (i = 0; i < n; i++) {
735 		device = devs[i];
736 
737 		if ((locators[PCICF_DEV] != PCICF_DEV_DEFAULT) &&
738 		    (locators[PCICF_DEV] != device))
739 			continue;
740 
741 		tag = pci_make_tag(pc, sc->sc_bus, device, 0);
742 
743 		id = pci_conf_read(pc, tag, PCI_ID_REG);
744 
745 		/* Invalid vendor ID value? */
746 		if (PCI_VENDOR(id) == PCI_VENDOR_INVALID)
747 			continue;
748 		/* XXX Not invalid, but we've done this ~forever. */
749 		if (PCI_VENDOR(id) == 0)
750 			continue;
751 
752 		bhlcr = pci_conf_read(pc, tag, PCI_BHLC_REG);
753 		if (PCI_HDRTYPE_TYPE(bhlcr) > 2)
754 			continue;
755 
756 		qd = pci_lookup_quirkdata(PCI_VENDOR(id), PCI_PRODUCT(id));
757 
758 		if (qd != NULL &&
759 		      (qd->quirks & PCI_QUIRK_MULTIFUNCTION) != 0)
760 			nfunctions = 8;
761 		else if (qd != NULL &&
762 		      (qd->quirks & PCI_QUIRK_MONOFUNCTION) != 0)
763 			nfunctions = 1;
764 		else if (arien)
765 			nfunctions = 8; /* Scan all if ARI is enabled */
766 		else
767 			nfunctions = PCI_HDRTYPE_MULTIFN(bhlcr) ? 8 : 1;
768 
769 #ifdef __PCI_DEV_FUNCORDER
770 		char funcs[8];
771 		int j;
772 		for (j = 0; j < nfunctions; j++) {
773 			funcs[j] = j;
774 		}
775 		if (j < __arraycount(funcs))
776 			funcs[j] = -1;
777 		if (nfunctions > 1) {
778 			pci_dev_funcorder(sc->sc_pc, sc->sc_bus, device,
779 			    nfunctions, funcs);
780 		}
781 		for (j = 0;
782 		     j < 8 && (function = funcs[j]) < 8 && function >= 0;
783 		     j++) {
784 #else
785 		for (function = 0; function < nfunctions; function++) {
786 #endif
787 			if ((locators[PCICF_FUNCTION] != PCICF_FUNCTION_DEFAULT)
788 			    && (locators[PCICF_FUNCTION] != function))
789 				continue;
790 
791 			if (qd != NULL &&
792 			    (qd->quirks & PCI_QUIRK_SKIP_FUNC(function)) != 0)
793 				continue;
794 			tag = pci_make_tag(pc, sc->sc_bus, device, function);
795 			ret = pci_probe_device(sc, tag, match, pap);
796 			if (match != NULL && ret != 0)
797 				return ret;
798 		}
799 	}
800 	return 0;
801 }
802 #endif /* PCI_MACHDEP_ENUMERATE_BUS */
803 
804 
805 /*
806  * Vital Product Data (PCI 2.2)
807  */
808 
809 int
810 pci_vpd_read(pci_chipset_tag_t pc, pcitag_t tag, int offset, int count,
811     pcireg_t *data)
812 {
813 	uint32_t reg;
814 	int ofs, i, j;
815 
816 	KASSERT(data != NULL);
817 	KASSERT((offset + count) < 0x7fff);
818 
819 	if (pci_get_capability(pc, tag, PCI_CAP_VPD, &ofs, &reg) == 0)
820 		return 1;
821 
822 	for (i = 0; i < count; offset += sizeof(*data), i++) {
823 		reg &= 0x0000ffff;
824 		reg &= ~PCI_VPD_OPFLAG;
825 		reg |= PCI_VPD_ADDRESS(offset);
826 		pci_conf_write(pc, tag, ofs, reg);
827 
828 		/*
829 		 * PCI 2.2 does not specify how long we should poll
830 		 * for completion nor whether the operation can fail.
831 		 */
832 		j = 0;
833 		do {
834 			if (j++ == 20)
835 				return 1;
836 			delay(4);
837 			reg = pci_conf_read(pc, tag, ofs);
838 		} while ((reg & PCI_VPD_OPFLAG) == 0);
839 		data[i] = pci_conf_read(pc, tag, PCI_VPD_DATAREG(ofs));
840 	}
841 
842 	return 0;
843 }
844 
845 int
846 pci_vpd_write(pci_chipset_tag_t pc, pcitag_t tag, int offset, int count,
847     pcireg_t *data)
848 {
849 	pcireg_t reg;
850 	int ofs, i, j;
851 
852 	KASSERT(data != NULL);
853 	KASSERT((offset + count) < 0x7fff);
854 
855 	if (pci_get_capability(pc, tag, PCI_CAP_VPD, &ofs, &reg) == 0)
856 		return 1;
857 
858 	for (i = 0; i < count; offset += sizeof(*data), i++) {
859 		pci_conf_write(pc, tag, PCI_VPD_DATAREG(ofs), data[i]);
860 
861 		reg &= 0x0000ffff;
862 		reg |= PCI_VPD_OPFLAG;
863 		reg |= PCI_VPD_ADDRESS(offset);
864 		pci_conf_write(pc, tag, ofs, reg);
865 
866 		/*
867 		 * PCI 2.2 does not specify how long we should poll
868 		 * for completion nor whether the operation can fail.
869 		 */
870 		j = 0;
871 		do {
872 			if (j++ == 20)
873 				return 1;
874 			delay(1);
875 			reg = pci_conf_read(pc, tag, ofs);
876 		} while (reg & PCI_VPD_OPFLAG);
877 	}
878 
879 	return 0;
880 }
881 
882 int
883 pci_dma64_available(const struct pci_attach_args *pa)
884 {
885 #ifdef _PCI_HAVE_DMA64
886 	if (BUS_DMA_TAG_VALID(pa->pa_dmat64))
887                         return 1;
888 #endif
889         return 0;
890 }
891 
892 void
893 pci_conf_capture(pci_chipset_tag_t pc, pcitag_t tag,
894 		  struct pci_conf_state *pcs)
895 {
896 	int off;
897 
898 	for (off = 0; off < 16; off++)
899 		pcs->reg[off] = pci_conf_read(pc, tag, (off * 4));
900 
901 	/* For PCI-X */
902 	if (pci_get_capability(pc, tag, PCI_CAP_PCIX, &off, NULL) != 0)
903 		pcs->x_csr = pci_conf_read(pc, tag, off + PCIX_CMD);
904 
905 	/* For PCIe */
906 	if (pci_get_capability(pc, tag, PCI_CAP_PCIEXPRESS, &off, NULL) != 0) {
907 		pcireg_t xcap = pci_conf_read(pc, tag, off + PCIE_XCAP);
908 		unsigned int devtype;
909 
910 		devtype = PCIE_XCAP_TYPE(xcap);
911 		pcs->e_dcr = (uint16_t)pci_conf_read(pc, tag, off + PCIE_DCSR);
912 
913 		if (PCIE_HAS_LINKREGS(devtype))
914 			pcs->e_lcr = (uint16_t)pci_conf_read(pc, tag,
915 			    off + PCIE_LCSR);
916 
917 		if ((xcap & PCIE_XCAP_SI) != 0)
918 			pcs->e_slcr = (uint16_t)pci_conf_read(pc, tag,
919 			    off + PCIE_SLCSR);
920 
921 		if (PCIE_HAS_ROOTREGS(devtype))
922 			pcs->e_rcr = (uint16_t)pci_conf_read(pc, tag,
923 			    off + PCIE_RCR);
924 
925 		if (__SHIFTOUT(xcap, PCIE_XCAP_VER_MASK) >= 2) {
926 			pcs->e_dcr2 = (uint16_t)pci_conf_read(pc, tag,
927 			    off + PCIE_DCSR2);
928 
929 			if (PCIE_HAS_LINKREGS(devtype))
930 				pcs->e_lcr2 = (uint16_t)pci_conf_read(pc, tag,
931 			    off + PCIE_LCSR2);
932 
933 			/* XXX PCIE_SLCSR2 (It's reserved by the PCIe spec) */
934 		}
935 	}
936 
937 	/* For MSI */
938 	if (pci_get_capability(pc, tag, PCI_CAP_MSI, &off, NULL) != 0) {
939 		bool bit64, pvmask;
940 
941 		pcs->msi_ctl = pci_conf_read(pc, tag, off + PCI_MSI_CTL);
942 
943 		bit64 = pcs->msi_ctl & PCI_MSI_CTL_64BIT_ADDR;
944 		pvmask = pcs->msi_ctl & PCI_MSI_CTL_PERVEC_MASK;
945 
946 		/* Address */
947 		pcs->msi_maddr = pci_conf_read(pc, tag, off + PCI_MSI_MADDR);
948 		if (bit64)
949 			pcs->msi_maddr64_hi = pci_conf_read(pc, tag,
950 			    off + PCI_MSI_MADDR64_HI);
951 
952 		/* Data */
953 		pcs->msi_mdata = pci_conf_read(pc, tag,
954 		    off + (bit64 ? PCI_MSI_MDATA64 : PCI_MSI_MDATA));
955 
956 		/* Per-vector masking */
957 		if (pvmask)
958 			pcs->msi_mask = pci_conf_read(pc, tag,
959 			    off + (bit64 ? PCI_MSI_MASK64 : PCI_MSI_MASK));
960 	}
961 
962 	/* For MSI-X */
963 	if (pci_get_capability(pc, tag, PCI_CAP_MSIX, &off, NULL) != 0)
964 		pcs->msix_ctl = pci_conf_read(pc, tag, off + PCI_MSIX_CTL);
965 }
966 
967 void
968 pci_conf_restore(pci_chipset_tag_t pc, pcitag_t tag,
969 		  struct pci_conf_state *pcs)
970 {
971 	int off;
972 	pcireg_t val;
973 
974 	for (off = 15; off >= 0; off--) {
975 		val = pci_conf_read(pc, tag, (off * 4));
976 		if (val != pcs->reg[off])
977 			pci_conf_write(pc, tag, (off * 4), pcs->reg[off]);
978 	}
979 
980 	/* For PCI-X */
981 	if (pci_get_capability(pc, tag, PCI_CAP_PCIX, &off, NULL) != 0)
982 		pci_conf_write(pc, tag, off + PCIX_CMD, pcs->x_csr);
983 
984 	/* For PCIe */
985 	if (pci_get_capability(pc, tag, PCI_CAP_PCIEXPRESS, &off, NULL) != 0) {
986 		pcireg_t xcap = pci_conf_read(pc, tag, off + PCIE_XCAP);
987 		unsigned int devtype;
988 
989 		devtype = PCIE_XCAP_TYPE(xcap);
990 		pci_conf_write(pc, tag, off + PCIE_DCSR, pcs->e_dcr);
991 
992 		/*
993 		 * PCIe capability is variable sized. To not to write the next
994 		 * area, check the existence of each register.
995 		 */
996 		if (PCIE_HAS_LINKREGS(devtype))
997 			pci_conf_write(pc, tag, off + PCIE_LCSR, pcs->e_lcr);
998 
999 		if ((xcap & PCIE_XCAP_SI) != 0)
1000 			pci_conf_write(pc, tag, off + PCIE_SLCSR, pcs->e_slcr);
1001 
1002 		if (PCIE_HAS_ROOTREGS(devtype))
1003 			pci_conf_write(pc, tag, off + PCIE_RCR, pcs->e_rcr);
1004 
1005 		if (__SHIFTOUT(xcap, PCIE_XCAP_VER_MASK) >= 2) {
1006 			pci_conf_write(pc, tag, off + PCIE_DCSR2, pcs->e_dcr2);
1007 
1008 			if (PCIE_HAS_LINKREGS(devtype))
1009 				pci_conf_write(pc, tag, off + PCIE_LCSR2,
1010 				    pcs->e_lcr2);
1011 
1012 			/* XXX PCIE_SLCSR2 (It's reserved by the PCIe spec) */
1013 		}
1014 	}
1015 
1016 	/* For MSI */
1017 	if (pci_get_capability(pc, tag, PCI_CAP_MSI, &off, NULL) != 0) {
1018 		pcireg_t reg;
1019 		bool bit64, pvmask;
1020 
1021 		/* First, drop Enable bit in case it's already set. */
1022 		reg = pci_conf_read(pc, tag, off + PCI_MSI_CTL);
1023 		pci_conf_write(pc, tag, off + PCI_MSI_CTL,
1024 		    reg & ~PCI_MSI_CTL_MSI_ENABLE);
1025 
1026 		bit64 = pcs->msi_ctl & PCI_MSI_CTL_64BIT_ADDR;
1027 		pvmask = pcs->msi_ctl & PCI_MSI_CTL_PERVEC_MASK;
1028 
1029 		/* Address */
1030 		pci_conf_write(pc, tag, off + PCI_MSI_MADDR, pcs->msi_maddr);
1031 
1032 		if (bit64)
1033 			pci_conf_write(pc, tag,
1034 			    off + PCI_MSI_MADDR64_HI, pcs->msi_maddr64_hi);
1035 
1036 		/* Data */
1037 		pci_conf_write(pc, tag,
1038 		    off + (bit64 ? PCI_MSI_MDATA64 : PCI_MSI_MDATA),
1039 		    pcs->msi_mdata);
1040 
1041 		/* Per-vector masking */
1042 		if (pvmask)
1043 			pci_conf_write(pc, tag,
1044 			    off + (bit64 ? PCI_MSI_MASK64 : PCI_MSI_MASK),
1045 			    pcs->msi_mask);
1046 
1047 		/* Write CTRL register in the end */
1048 		pci_conf_write(pc, tag, off + PCI_MSI_CTL, pcs->msi_ctl);
1049 	}
1050 
1051 	/* For MSI-X */
1052 	if (pci_get_capability(pc, tag, PCI_CAP_MSIX, &off, NULL) != 0)
1053 		pci_conf_write(pc, tag, off + PCI_MSIX_CTL, pcs->msix_ctl);
1054 }
1055 
1056 /*
1057  * Power Management Capability (Rev 2.2)
1058  */
1059 static int
1060 pci_get_powerstate_int(pci_chipset_tag_t pc, pcitag_t tag , pcireg_t *state,
1061     int offset)
1062 {
1063 	pcireg_t value, now;
1064 
1065 	value = pci_conf_read(pc, tag, offset + PCI_PMCSR);
1066 	now = value & PCI_PMCSR_STATE_MASK;
1067 	switch (now) {
1068 	case PCI_PMCSR_STATE_D0:
1069 	case PCI_PMCSR_STATE_D1:
1070 	case PCI_PMCSR_STATE_D2:
1071 	case PCI_PMCSR_STATE_D3:
1072 		*state = now;
1073 		return 0;
1074 	default:
1075 		return EINVAL;
1076 	}
1077 }
1078 
1079 int
1080 pci_get_powerstate(pci_chipset_tag_t pc, pcitag_t tag , pcireg_t *state)
1081 {
1082 	int offset;
1083 	pcireg_t value;
1084 
1085 	if (!pci_get_capability(pc, tag, PCI_CAP_PWRMGMT, &offset, &value))
1086 		return EOPNOTSUPP;
1087 
1088 	return pci_get_powerstate_int(pc, tag, state, offset);
1089 }
1090 
1091 static int
1092 pci_set_powerstate_int(pci_chipset_tag_t pc, pcitag_t tag, pcireg_t state,
1093     int offset, pcireg_t cap_reg)
1094 {
1095 	pcireg_t value, cap, now;
1096 
1097 	cap = cap_reg >> PCI_PMCR_SHIFT;
1098 	value = pci_conf_read(pc, tag, offset + PCI_PMCSR);
1099 	now = value & PCI_PMCSR_STATE_MASK;
1100 	value &= ~PCI_PMCSR_STATE_MASK;
1101 
1102 	if (now == state)
1103 		return 0;
1104 	switch (state) {
1105 	case PCI_PMCSR_STATE_D0:
1106 		break;
1107 	case PCI_PMCSR_STATE_D1:
1108 		if (now == PCI_PMCSR_STATE_D2 || now == PCI_PMCSR_STATE_D3) {
1109 			printf("invalid transition from %d to D1\n", (int)now);
1110 			return EINVAL;
1111 		}
1112 		if (!(cap & PCI_PMCR_D1SUPP)) {
1113 			printf("D1 not supported\n");
1114 			return EOPNOTSUPP;
1115 		}
1116 		break;
1117 	case PCI_PMCSR_STATE_D2:
1118 		if (now == PCI_PMCSR_STATE_D3) {
1119 			printf("invalid transition from %d to D2\n", (int)now);
1120 			return EINVAL;
1121 		}
1122 		if (!(cap & PCI_PMCR_D2SUPP)) {
1123 			printf("D2 not supported\n");
1124 			return EOPNOTSUPP;
1125 		}
1126 		break;
1127 	case PCI_PMCSR_STATE_D3:
1128 		break;
1129 	default:
1130 		return EINVAL;
1131 	}
1132 	value |= state;
1133 	pci_conf_write(pc, tag, offset + PCI_PMCSR, value);
1134 	/* delay according to pcipm1.2, ch. 5.6.1 */
1135 	if (state == PCI_PMCSR_STATE_D3 || now == PCI_PMCSR_STATE_D3)
1136 		DELAY(10000);
1137 	else if (state == PCI_PMCSR_STATE_D2 || now == PCI_PMCSR_STATE_D2)
1138 		DELAY(200);
1139 
1140 	return 0;
1141 }
1142 
1143 int
1144 pci_set_powerstate(pci_chipset_tag_t pc, pcitag_t tag, pcireg_t state)
1145 {
1146 	int offset;
1147 	pcireg_t value;
1148 
1149 	if (!pci_get_capability(pc, tag, PCI_CAP_PWRMGMT, &offset, &value)) {
1150 		printf("pci_set_powerstate not supported\n");
1151 		return EOPNOTSUPP;
1152 	}
1153 
1154 	return pci_set_powerstate_int(pc, tag, state, offset, value);
1155 }
1156 
1157 int
1158 pci_activate(pci_chipset_tag_t pc, pcitag_t tag, device_t dev,
1159     int (*wakefun)(pci_chipset_tag_t, pcitag_t, device_t, pcireg_t))
1160 {
1161 	pcireg_t pmode;
1162 	int error;
1163 
1164 	if ((error = pci_get_powerstate(pc, tag, &pmode)))
1165 		return error;
1166 
1167 	switch (pmode) {
1168 	case PCI_PMCSR_STATE_D0:
1169 		break;
1170 	case PCI_PMCSR_STATE_D3:
1171 		if (wakefun == NULL) {
1172 			/*
1173 			 * The card has lost all configuration data in
1174 			 * this state, so punt.
1175 			 */
1176 			aprint_error_dev(dev,
1177 			    "unable to wake up from power state D3\n");
1178 			return EOPNOTSUPP;
1179 		}
1180 		/*FALLTHROUGH*/
1181 	default:
1182 		if (wakefun) {
1183 			error = (*wakefun)(pc, tag, dev, pmode);
1184 			if (error)
1185 				return error;
1186 		}
1187 		aprint_normal_dev(dev, "waking up from power state D%d\n",
1188 		    pmode);
1189 		if ((error = pci_set_powerstate(pc, tag, PCI_PMCSR_STATE_D0)))
1190 			return error;
1191 	}
1192 	return 0;
1193 }
1194 
1195 int
1196 pci_activate_null(pci_chipset_tag_t pc, pcitag_t tag,
1197     device_t dev, pcireg_t state)
1198 {
1199 	return 0;
1200 }
1201 
1202 struct pci_child_power {
1203 	struct pci_conf_state p_pciconf;
1204 	pci_chipset_tag_t p_pc;
1205 	pcitag_t p_tag;
1206 	bool p_has_pm;
1207 	int p_pm_offset;
1208 	pcireg_t p_pm_cap;
1209 	pcireg_t p_class;
1210 	pcireg_t p_csr;
1211 };
1212 
1213 static bool
1214 pci_child_suspend(device_t dv, const pmf_qual_t *qual)
1215 {
1216 	struct pci_child_power *priv = device_pmf_bus_private(dv);
1217 	pcireg_t ocsr, csr;
1218 
1219 	pci_conf_capture(priv->p_pc, priv->p_tag, &priv->p_pciconf);
1220 
1221 	if (!priv->p_has_pm)
1222 		return true; /* ??? hopefully handled by ACPI */
1223 	if (PCI_CLASS(priv->p_class) == PCI_CLASS_DISPLAY)
1224 		return true; /* XXX */
1225 
1226 	/* disable decoding and busmastering, see pcipm1.2 ch. 8.2.1 */
1227 	ocsr = pci_conf_read(priv->p_pc, priv->p_tag, PCI_COMMAND_STATUS_REG);
1228 	csr = ocsr & ~(PCI_COMMAND_IO_ENABLE | PCI_COMMAND_MEM_ENABLE
1229 		       | PCI_COMMAND_MASTER_ENABLE);
1230 	pci_conf_write(priv->p_pc, priv->p_tag, PCI_COMMAND_STATUS_REG, csr);
1231 	if (pci_set_powerstate_int(priv->p_pc, priv->p_tag,
1232 	    PCI_PMCSR_STATE_D3, priv->p_pm_offset, priv->p_pm_cap)) {
1233 		pci_conf_write(priv->p_pc, priv->p_tag,
1234 			       PCI_COMMAND_STATUS_REG, ocsr);
1235 		aprint_error_dev(dv, "unsupported state, continuing.\n");
1236 		return false;
1237 	}
1238 	return true;
1239 }
1240 
1241 static void
1242 pci_pme_check_and_clear(device_t dv, pci_chipset_tag_t pc, pcitag_t tag,
1243     int off)
1244 {
1245 	pcireg_t pmcsr;
1246 
1247 	pmcsr = pci_conf_read(pc, tag, off + PCI_PMCSR);
1248 
1249 	if (pmcsr & PCI_PMCSR_PME_STS) {
1250 		/* Clear W1C bit */
1251 		pmcsr |= PCI_PMCSR_PME_STS;
1252 		pci_conf_write(pc, tag, off + PCI_PMCSR, pmcsr);
1253 		aprint_verbose_dev(dv, "Clear PME# now\n");
1254 	}
1255 }
1256 
1257 static bool
1258 pci_child_resume(device_t dv, const pmf_qual_t *qual)
1259 {
1260 	struct pci_child_power *priv = device_pmf_bus_private(dv);
1261 
1262 	if (priv->p_has_pm) {
1263 		if (pci_set_powerstate_int(priv->p_pc, priv->p_tag,
1264 		    PCI_PMCSR_STATE_D0, priv->p_pm_offset, priv->p_pm_cap)) {
1265 			aprint_error_dev(dv,
1266 			    "unsupported state, continuing.\n");
1267 			return false;
1268 		}
1269 		pci_pme_check_and_clear(dv, priv->p_pc, priv->p_tag,
1270 		    priv->p_pm_offset);
1271 	}
1272 
1273 	pci_conf_restore(priv->p_pc, priv->p_tag, &priv->p_pciconf);
1274 
1275 	return true;
1276 }
1277 
1278 static bool
1279 pci_child_shutdown(device_t dv, int how)
1280 {
1281 	struct pci_child_power *priv = device_pmf_bus_private(dv);
1282 	pcireg_t csr;
1283 
1284 	/* restore original bus-mastering state */
1285 	csr = pci_conf_read(priv->p_pc, priv->p_tag, PCI_COMMAND_STATUS_REG);
1286 	csr &= ~PCI_COMMAND_MASTER_ENABLE;
1287 	csr |= priv->p_csr & PCI_COMMAND_MASTER_ENABLE;
1288 	pci_conf_write(priv->p_pc, priv->p_tag, PCI_COMMAND_STATUS_REG, csr);
1289 	return true;
1290 }
1291 
1292 static void
1293 pci_child_deregister(device_t dv)
1294 {
1295 	struct pci_child_power *priv = device_pmf_bus_private(dv);
1296 
1297 	free(priv, M_DEVBUF);
1298 }
1299 
1300 static bool
1301 pci_child_register(device_t child)
1302 {
1303 	device_t self = device_parent(child);
1304 	struct pci_softc *sc = device_private(self);
1305 	struct pci_child_power *priv;
1306 	int device, function, off;
1307 	pcireg_t reg;
1308 
1309 	priv = malloc(sizeof(*priv), M_DEVBUF, M_WAITOK);
1310 
1311 	device = device_locator(child, PCICF_DEV);
1312 	function = device_locator(child, PCICF_FUNCTION);
1313 
1314 	priv->p_pc = sc->sc_pc;
1315 	priv->p_tag = pci_make_tag(priv->p_pc, sc->sc_bus, device,
1316 	    function);
1317 	priv->p_class = pci_conf_read(priv->p_pc, priv->p_tag, PCI_CLASS_REG);
1318 	priv->p_csr = pci_conf_read(priv->p_pc, priv->p_tag,
1319 	    PCI_COMMAND_STATUS_REG);
1320 
1321 	if (pci_get_capability(priv->p_pc, priv->p_tag,
1322 			       PCI_CAP_PWRMGMT, &off, &reg)) {
1323 		priv->p_has_pm = true;
1324 		priv->p_pm_offset = off;
1325 		priv->p_pm_cap = reg;
1326 		pci_pme_check_and_clear(child, priv->p_pc, priv->p_tag, off);
1327 	} else {
1328 		priv->p_has_pm = false;
1329 		priv->p_pm_offset = -1;
1330 	}
1331 
1332 	device_pmf_bus_register(child, priv, pci_child_suspend,
1333 	    pci_child_resume, pci_child_shutdown, pci_child_deregister);
1334 
1335 	return true;
1336 }
1337 
1338 MODULE(MODULE_CLASS_DRIVER, pci, NULL);
1339 
1340 static int
1341 pci_modcmd(modcmd_t cmd, void *priv)
1342 {
1343 	if (cmd == MODULE_CMD_INIT || cmd == MODULE_CMD_FINI)
1344 		return 0;
1345 	return ENOTTY;
1346 }
1347