xref: /netbsd-src/sys/dev/pci/pci.c (revision 7c3f385475147b6e1c4753f2bee961630e2dfc40)
1 /*	$NetBSD: pci.c,v 1.116 2008/04/09 17:01:53 dyoung 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 1.116 2008/04/09 17:01:53 dyoung Exp $");
40 
41 #include "opt_pci.h"
42 
43 #include <sys/param.h>
44 #include <sys/malloc.h>
45 #include <sys/systm.h>
46 #include <sys/device.h>
47 
48 #include <dev/pci/pcireg.h>
49 #include <dev/pci/pcivar.h>
50 #include <dev/pci/pcidevs.h>
51 
52 #include <uvm/uvm_extern.h>
53 
54 #include <net/if.h>
55 
56 #include "locators.h"
57 
58 static bool pci_child_register(device_t);
59 
60 #ifdef PCI_CONFIG_DUMP
61 int pci_config_dump = 1;
62 #else
63 int pci_config_dump = 0;
64 #endif
65 
66 int	pciprint(void *, const char *);
67 
68 #ifdef PCI_MACHDEP_ENUMERATE_BUS
69 #define pci_enumerate_bus PCI_MACHDEP_ENUMERATE_BUS
70 #else
71 int pci_enumerate_bus(struct pci_softc *, const int *,
72     int (*)(struct pci_attach_args *), struct pci_attach_args *);
73 #endif
74 
75 /*
76  * Important note about PCI-ISA bridges:
77  *
78  * Callbacks are used to configure these devices so that ISA/EISA bridges
79  * can attach their child busses after PCI configuration is done.
80  *
81  * This works because:
82  *	(1) there can be at most one ISA/EISA bridge per PCI bus, and
83  *	(2) any ISA/EISA bridges must be attached to primary PCI
84  *	    busses (i.e. bus zero).
85  *
86  * That boils down to: there can only be one of these outstanding
87  * at a time, it is cleared when configuring PCI bus 0 before any
88  * subdevices have been found, and it is run after all subdevices
89  * of PCI bus 0 have been found.
90  *
91  * This is needed because there are some (legacy) PCI devices which
92  * can show up as ISA/EISA devices as well (the prime example of which
93  * are VGA controllers).  If you attach ISA from a PCI-ISA/EISA bridge,
94  * and the bridge is seen before the video board is, the board can show
95  * up as an ISA device, and that can (bogusly) complicate the PCI device's
96  * attach code, or make the PCI device not be properly attached at all.
97  *
98  * We use the generic config_defer() facility to achieve this.
99  */
100 
101 int
102 pcirescan(device_t self, const char *ifattr, const int *locators)
103 {
104 	struct pci_softc *sc = device_private(self);
105 
106 	KASSERT(ifattr && !strcmp(ifattr, "pci"));
107 	KASSERT(locators);
108 
109 	pci_enumerate_bus(sc, locators, NULL, NULL);
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_ENABLED);
153 	mem_enabled = (pba->pba_flags & PCI_FLAGS_MEM_ENABLED);
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_ENABLED ? "on" : "off",
252 		    pa->pa_flags & PCI_FLAGS_MEM_ENABLED ? "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 			bitmask_snprintf(qd->quirks,
259 			    "\002\001multifn\002singlefn\003skipfunc0"
260 			    "\004skipfunc1\005skipfunc2\006skipfunc3"
261 			    "\007skipfunc4\010skipfunc5\011skipfunc6"
262 			    "\012skipfunc7",
263 			    devinfo, sizeof (devinfo));
264 			printf(" quirks %s", devinfo);
265 		}
266 		printf(")");
267 	}
268 	return (UNCONF);
269 }
270 
271 int
272 pci_probe_device(struct pci_softc *sc, pcitag_t tag,
273     int (*match)(struct pci_attach_args *), 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, class, intr, bhlcr;
278 	int ret, pin, bus, device, function;
279 	int locs[PCICF_NLOCS];
280 	device_t subdev;
281 
282 	pci_decompose_tag(pc, tag, &bus, &device, &function);
283 
284 	/* a driver already attached? */
285 	if (sc->PCI_SC_DEVICESC(device, function) && !match)
286 		return (0);
287 
288 	bhlcr = pci_conf_read(pc, tag, PCI_BHLC_REG);
289 	if (PCI_HDRTYPE_TYPE(bhlcr) > 2)
290 		return (0);
291 
292 	id = pci_conf_read(pc, tag, PCI_ID_REG);
293 	csr = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
294 	class = pci_conf_read(pc, tag, PCI_CLASS_REG);
295 
296 	/* Invalid vendor ID value? */
297 	if (PCI_VENDOR(id) == PCI_VENDOR_INVALID)
298 		return (0);
299 	/* XXX Not invalid, but we've done this ~forever. */
300 	if (PCI_VENDOR(id) == 0)
301 		return (0);
302 
303 	pa.pa_iot = sc->sc_iot;
304 	pa.pa_memt = sc->sc_memt;
305 	pa.pa_dmat = sc->sc_dmat;
306 	pa.pa_dmat64 = sc->sc_dmat64;
307 	pa.pa_pc = pc;
308 	pa.pa_bus = bus;
309 	pa.pa_device = device;
310 	pa.pa_function = function;
311 	pa.pa_tag = tag;
312 	pa.pa_id = id;
313 	pa.pa_class = class;
314 
315 	/*
316 	 * Set up memory, I/O enable, and PCI command flags
317 	 * as appropriate.
318 	 */
319 	pa.pa_flags = sc->sc_flags;
320 	if ((csr & PCI_COMMAND_IO_ENABLE) == 0)
321 		pa.pa_flags &= ~PCI_FLAGS_IO_ENABLED;
322 	if ((csr & PCI_COMMAND_MEM_ENABLE) == 0)
323 		pa.pa_flags &= ~PCI_FLAGS_MEM_ENABLED;
324 
325 	/*
326 	 * If the cache line size is not configured, then
327 	 * clear the MRL/MRM/MWI command-ok flags.
328 	 */
329 	if (PCI_CACHELINE(bhlcr) == 0)
330 		pa.pa_flags &= ~(PCI_FLAGS_MRL_OKAY|
331 		    PCI_FLAGS_MRM_OKAY|PCI_FLAGS_MWI_OKAY);
332 
333 	if (sc->sc_bridgetag == NULL) {
334 		pa.pa_intrswiz = 0;
335 		pa.pa_intrtag = tag;
336 	} else {
337 		pa.pa_intrswiz = sc->sc_intrswiz + device;
338 		pa.pa_intrtag = sc->sc_intrtag;
339 	}
340 
341 	intr = pci_conf_read(pc, tag, PCI_INTERRUPT_REG);
342 
343 	pin = PCI_INTERRUPT_PIN(intr);
344 	pa.pa_rawintrpin = pin;
345 	if (pin == PCI_INTERRUPT_PIN_NONE) {
346 		/* no interrupt */
347 		pa.pa_intrpin = 0;
348 	} else {
349 		/*
350 		 * swizzle it based on the number of busses we're
351 		 * behind and our device number.
352 		 */
353 		pa.pa_intrpin = 	/* XXX */
354 		    ((pin + pa.pa_intrswiz - 1) % 4) + 1;
355 	}
356 	pa.pa_intrline = PCI_INTERRUPT_LINE(intr);
357 
358 	if (match != NULL) {
359 		ret = (*match)(&pa);
360 		if (ret != 0 && pap != NULL)
361 			*pap = pa;
362 	} else {
363 		locs[PCICF_DEV] = device;
364 		locs[PCICF_FUNCTION] = function;
365 
366 		subdev = config_found_sm_loc(sc->sc_dev, "pci", locs, &pa,
367 					     pciprint, config_stdsubmatch);
368 		sc->PCI_SC_DEVICESC(device, function) = subdev;
369 		ret = (subdev != NULL);
370 	}
371 
372 	return (ret);
373 }
374 
375 void
376 pcidevdetached(device_t self, device_t child)
377 {
378 	struct pci_softc *psc = device_private(self);
379 	int d, f;
380 
381 	d = device_locator(child, PCICF_DEV);
382 	f = device_locator(child, PCICF_FUNCTION);
383 
384 	KASSERT(psc->PCI_SC_DEVICESC(d, f) == child);
385 
386 	psc->PCI_SC_DEVICESC(d, f) = 0;
387 }
388 
389 CFATTACH_DECL2_NEW(pci, sizeof(struct pci_softc),
390     pcimatch, pciattach, pcidetach, NULL, pcirescan, pcidevdetached);
391 
392 int
393 pci_get_capability(pci_chipset_tag_t pc, pcitag_t tag, int capid,
394     int *offset, pcireg_t *value)
395 {
396 	pcireg_t reg;
397 	unsigned int ofs;
398 
399 	reg = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
400 	if (!(reg & PCI_STATUS_CAPLIST_SUPPORT))
401 		return (0);
402 
403 	/* Determine the Capability List Pointer register to start with. */
404 	reg = pci_conf_read(pc, tag, PCI_BHLC_REG);
405 	switch (PCI_HDRTYPE_TYPE(reg)) {
406 	case 0:	/* standard device header */
407 	case 1: /* PCI-PCI bridge header */
408 		ofs = PCI_CAPLISTPTR_REG;
409 		break;
410 	case 2:	/* PCI-CardBus Bridge header */
411 		ofs = PCI_CARDBUS_CAPLISTPTR_REG;
412 		break;
413 	default:
414 		return (0);
415 	}
416 
417 	ofs = PCI_CAPLIST_PTR(pci_conf_read(pc, tag, ofs));
418 	while (ofs != 0) {
419 #ifdef DIAGNOSTIC
420 		if ((ofs & 3) || (ofs < 0x40))
421 			panic("pci_get_capability");
422 #endif
423 		reg = pci_conf_read(pc, tag, ofs);
424 		if (PCI_CAPLIST_CAP(reg) == capid) {
425 			if (offset)
426 				*offset = ofs;
427 			if (value)
428 				*value = reg;
429 			return (1);
430 		}
431 		ofs = PCI_CAPLIST_NEXT(reg);
432 	}
433 
434 	return (0);
435 }
436 
437 int
438 pci_find_device(struct pci_attach_args *pa,
439 		int (*match)(struct pci_attach_args *))
440 {
441 	extern struct cfdriver pci_cd;
442 	device_t pcidev;
443 	int i;
444 	static const int wildcard[2] = {
445 		PCICF_DEV_DEFAULT,
446 		PCICF_FUNCTION_DEFAULT
447 	};
448 
449 	for (i = 0; i < pci_cd.cd_ndevs; i++) {
450 		pcidev = pci_cd.cd_devs[i];
451 		if (pcidev != NULL &&
452 		    pci_enumerate_bus(device_private(pcidev), wildcard,
453 		    		      match, pa) != 0)
454 			return (1);
455 	}
456 	return (0);
457 }
458 
459 #ifndef PCI_MACHDEP_ENUMERATE_BUS
460 /*
461  * Generic PCI bus enumeration routine.  Used unless machine-dependent
462  * code needs to provide something else.
463  */
464 int
465 pci_enumerate_bus(struct pci_softc *sc, const int *locators,
466     int (*match)(struct pci_attach_args *), struct pci_attach_args *pap)
467 {
468 	pci_chipset_tag_t pc = sc->sc_pc;
469 	int device, function, nfunctions, ret;
470 	const struct pci_quirkdata *qd;
471 	pcireg_t id, bhlcr;
472 	pcitag_t tag;
473 #ifdef __PCI_BUS_DEVORDER
474 	char devs[32];
475 	int i;
476 #endif
477 
478 #ifdef __PCI_BUS_DEVORDER
479 	pci_bus_devorder(sc->sc_pc, sc->sc_bus, devs);
480 	for (i = 0; (device = devs[i]) < 32 && device >= 0; i++)
481 #else
482 	for (device = 0; device < sc->sc_maxndevs; device++)
483 #endif
484 	{
485 		if ((locators[PCICF_DEV] != PCICF_DEV_DEFAULT) &&
486 		    (locators[PCICF_DEV] != device))
487 			continue;
488 
489 		tag = pci_make_tag(pc, sc->sc_bus, device, 0);
490 
491 		bhlcr = pci_conf_read(pc, tag, PCI_BHLC_REG);
492 		if (PCI_HDRTYPE_TYPE(bhlcr) > 2)
493 			continue;
494 
495 		id = pci_conf_read(pc, tag, PCI_ID_REG);
496 
497 		/* Invalid vendor ID value? */
498 		if (PCI_VENDOR(id) == PCI_VENDOR_INVALID)
499 			continue;
500 		/* XXX Not invalid, but we've done this ~forever. */
501 		if (PCI_VENDOR(id) == 0)
502 			continue;
503 
504 		qd = pci_lookup_quirkdata(PCI_VENDOR(id), PCI_PRODUCT(id));
505 
506 		if (qd != NULL &&
507 		      (qd->quirks & PCI_QUIRK_MULTIFUNCTION) != 0)
508 			nfunctions = 8;
509 		else if (qd != NULL &&
510 		      (qd->quirks & PCI_QUIRK_MONOFUNCTION) != 0)
511 			nfunctions = 1;
512 		else
513 			nfunctions = PCI_HDRTYPE_MULTIFN(bhlcr) ? 8 : 1;
514 
515 		for (function = 0; function < nfunctions; function++) {
516 			if ((locators[PCICF_FUNCTION] != PCICF_FUNCTION_DEFAULT)
517 			    && (locators[PCICF_FUNCTION] != function))
518 				continue;
519 
520 			if (qd != NULL &&
521 			    (qd->quirks & PCI_QUIRK_SKIP_FUNC(function)) != 0)
522 				continue;
523 			tag = pci_make_tag(pc, sc->sc_bus, device, function);
524 			ret = pci_probe_device(sc, tag, match, pap);
525 			if (match != NULL && ret != 0)
526 				return (ret);
527 		}
528 	}
529 	return (0);
530 }
531 #endif /* PCI_MACHDEP_ENUMERATE_BUS */
532 
533 
534 /*
535  * Vital Product Data (PCI 2.2)
536  */
537 
538 int
539 pci_vpd_read(pci_chipset_tag_t pc, pcitag_t tag, int offset, int count,
540     pcireg_t *data)
541 {
542 	uint32_t reg;
543 	int ofs, i, j;
544 
545 	KASSERT(data != NULL);
546 	KASSERT((offset + count) < 0x7fff);
547 
548 	if (pci_get_capability(pc, tag, PCI_CAP_VPD, &ofs, &reg) == 0)
549 		return (1);
550 
551 	for (i = 0; i < count; offset += sizeof(*data), i++) {
552 		reg &= 0x0000ffff;
553 		reg &= ~PCI_VPD_OPFLAG;
554 		reg |= PCI_VPD_ADDRESS(offset);
555 		pci_conf_write(pc, tag, ofs, reg);
556 
557 		/*
558 		 * PCI 2.2 does not specify how long we should poll
559 		 * for completion nor whether the operation can fail.
560 		 */
561 		j = 0;
562 		do {
563 			if (j++ == 20)
564 				return (1);
565 			delay(4);
566 			reg = pci_conf_read(pc, tag, ofs);
567 		} while ((reg & PCI_VPD_OPFLAG) == 0);
568 		data[i] = pci_conf_read(pc, tag, PCI_VPD_DATAREG(ofs));
569 	}
570 
571 	return (0);
572 }
573 
574 int
575 pci_vpd_write(pci_chipset_tag_t pc, pcitag_t tag, int offset, int count,
576     pcireg_t *data)
577 {
578 	pcireg_t reg;
579 	int ofs, i, j;
580 
581 	KASSERT(data != NULL);
582 	KASSERT((offset + count) < 0x7fff);
583 
584 	if (pci_get_capability(pc, tag, PCI_CAP_VPD, &ofs, &reg) == 0)
585 		return (1);
586 
587 	for (i = 0; i < count; offset += sizeof(*data), i++) {
588 		pci_conf_write(pc, tag, PCI_VPD_DATAREG(ofs), data[i]);
589 
590 		reg &= 0x0000ffff;
591 		reg |= PCI_VPD_OPFLAG;
592 		reg |= PCI_VPD_ADDRESS(offset);
593 		pci_conf_write(pc, tag, ofs, reg);
594 
595 		/*
596 		 * PCI 2.2 does not specify how long we should poll
597 		 * for completion nor whether the operation can fail.
598 		 */
599 		j = 0;
600 		do {
601 			if (j++ == 20)
602 				return (1);
603 			delay(1);
604 			reg = pci_conf_read(pc, tag, ofs);
605 		} while (reg & PCI_VPD_OPFLAG);
606 	}
607 
608 	return (0);
609 }
610 
611 int
612 pci_dma64_available(struct pci_attach_args *pa)
613 {
614 #ifdef _PCI_HAVE_DMA64
615 	if (BUS_DMA_TAG_VALID(pa->pa_dmat64) &&
616 		((uint64_t)physmem << PAGE_SHIFT) > 0xffffffffULL)
617                         return 1;
618 #endif
619         return 0;
620 }
621 
622 void
623 pci_conf_capture(pci_chipset_tag_t pc, pcitag_t tag,
624 		  struct pci_conf_state *pcs)
625 {
626 	int off;
627 
628 	for (off = 0; off < 16; off++)
629 		pcs->reg[off] = pci_conf_read(pc, tag, (off * 4));
630 
631 	return;
632 }
633 
634 void
635 pci_conf_restore(pci_chipset_tag_t pc, pcitag_t tag,
636 		  struct pci_conf_state *pcs)
637 {
638 	int off;
639 	pcireg_t val;
640 
641 	for (off = 15; off >= 0; off--) {
642 		val = pci_conf_read(pc, tag, (off * 4));
643 		if (val != pcs->reg[off])
644 			pci_conf_write(pc, tag, (off * 4), pcs->reg[off]);
645 	}
646 
647 	return;
648 }
649 
650 /*
651  * Power Management Capability (Rev 2.2)
652  */
653 static int
654 pci_get_powerstate_int(pci_chipset_tag_t pc, pcitag_t tag , pcireg_t *state,
655     int offset)
656 {
657 	pcireg_t value, now;
658 
659 	value = pci_conf_read(pc, tag, offset + PCI_PMCSR);
660 	now = value & PCI_PMCSR_STATE_MASK;
661 	switch (now) {
662 	case PCI_PMCSR_STATE_D0:
663 	case PCI_PMCSR_STATE_D1:
664 	case PCI_PMCSR_STATE_D2:
665 	case PCI_PMCSR_STATE_D3:
666 		*state = now;
667 		return 0;
668 	default:
669 		return EINVAL;
670 	}
671 }
672 
673 int
674 pci_get_powerstate(pci_chipset_tag_t pc, pcitag_t tag , pcireg_t *state)
675 {
676 	int offset;
677 	pcireg_t value;
678 
679 	if (!pci_get_capability(pc, tag, PCI_CAP_PWRMGMT, &offset, &value))
680 		return EOPNOTSUPP;
681 
682 	return pci_get_powerstate_int(pc, tag, state, offset);
683 }
684 
685 static int
686 pci_set_powerstate_int(pci_chipset_tag_t pc, pcitag_t tag, pcireg_t state,
687     int offset, pcireg_t cap_reg)
688 {
689 	pcireg_t value, cap, now;
690 
691 	cap = cap_reg >> PCI_PMCR_SHIFT;
692 	value = pci_conf_read(pc, tag, offset + PCI_PMCSR);
693 	now = value & PCI_PMCSR_STATE_MASK;
694 	value &= ~PCI_PMCSR_STATE_MASK;
695 
696 	if (now == state)
697 		return 0;
698 	switch (state) {
699 	case PCI_PMCSR_STATE_D0:
700 		break;
701 	case PCI_PMCSR_STATE_D1:
702 		if (now == PCI_PMCSR_STATE_D2 || now == PCI_PMCSR_STATE_D3) {
703 			printf("invalid transition from %d to D1\n", (int)now);
704 			return EINVAL;
705 		}
706 		if (!(cap & PCI_PMCR_D1SUPP)) {
707 			printf("D1 not supported\n");
708 			return EOPNOTSUPP;
709 		}
710 		break;
711 	case PCI_PMCSR_STATE_D2:
712 		if (now == PCI_PMCSR_STATE_D3) {
713 			printf("invalid transition from %d to D2\n", (int)now);
714 			return EINVAL;
715 		}
716 		if (!(cap & PCI_PMCR_D2SUPP)) {
717 			printf("D2 not supported\n");
718 			return EOPNOTSUPP;
719 		}
720 		break;
721 	case PCI_PMCSR_STATE_D3:
722 		break;
723 	default:
724 		return EINVAL;
725 	}
726 	value |= state;
727 	pci_conf_write(pc, tag, offset + PCI_PMCSR, value);
728 	/* delay according to pcipm1.2, ch. 5.6.1 */
729 	if (state == PCI_PMCSR_STATE_D3 || now == PCI_PMCSR_STATE_D3)
730 		DELAY(10000);
731 	else if (state == PCI_PMCSR_STATE_D2 || now == PCI_PMCSR_STATE_D2)
732 		DELAY(200);
733 
734 	return 0;
735 }
736 
737 int
738 pci_set_powerstate(pci_chipset_tag_t pc, pcitag_t tag, pcireg_t state)
739 {
740 	int offset;
741 	pcireg_t value;
742 
743 	if (!pci_get_capability(pc, tag, PCI_CAP_PWRMGMT, &offset, &value)) {
744 		printf("pci_set_powerstate not supported\n");
745 		return EOPNOTSUPP;
746 	}
747 
748 	return pci_set_powerstate_int(pc, tag, state, offset, value);
749 }
750 
751 int
752 pci_activate(pci_chipset_tag_t pc, pcitag_t tag, device_t dev,
753     int (*wakefun)(pci_chipset_tag_t, pcitag_t, device_t, pcireg_t))
754 {
755 	pcireg_t pmode;
756 	int error;
757 
758 	if ((error = pci_get_powerstate(pc, tag, &pmode)))
759 		return error;
760 
761 	switch (pmode) {
762 	case PCI_PMCSR_STATE_D0:
763 		break;
764 	case PCI_PMCSR_STATE_D3:
765 		if (wakefun == NULL) {
766 			/*
767 			 * The card has lost all configuration data in
768 			 * this state, so punt.
769 			 */
770 			aprint_error_dev(dev,
771 			    "unable to wake up from power state D3\n");
772 			return EOPNOTSUPP;
773 		}
774 		/*FALLTHROUGH*/
775 	default:
776 		if (wakefun) {
777 			error = (*wakefun)(pc, tag, dev, pmode);
778 			if (error)
779 				return error;
780 		}
781 		aprint_normal_dev(dev, "waking up from power state D%d\n",
782 		    pmode);
783 		if ((error = pci_set_powerstate(pc, tag, PCI_PMCSR_STATE_D0)))
784 			return error;
785 	}
786 	return 0;
787 }
788 
789 int
790 pci_activate_null(pci_chipset_tag_t pc, pcitag_t tag,
791     device_t dev, pcireg_t state)
792 {
793 	return 0;
794 }
795 
796 /* I have disabled this code for now. --dyoung
797  *
798  * Insofar as I understand what the PCI retry timeout is [1],
799  * I see no justification for any driver to disable when it
800  * attaches/resumes a device.
801  *
802  * A PCI bus bridge may tell a bus master to retry its transaction
803  * at a later time if the resources to complete the transaction
804  * are not immediately available.  Taking a guess, PCI bus masters
805  * that implement a PCI retry timeout register count down from the
806  * retry timeout to 0 while it retries a delayed PCI transaction.
807  * When it reaches 0, it stops retrying.  A PCI master is *never*
808  * supposed to stop retrying a delayed transaction, though.
809  *
810  * Incidentally, I initially suspected that writing 0 to the register
811  * would not disable *retries*, but would disable the timeout.
812  * That is, any device whose retry timeout was set to 0 would
813  * *never* timeout.  However, I found out, by using PCI debug
814  * facilities on the AMD Elan SC520, that if I write 0 to the retry
815  * timeout register on an ath(4) MiniPCI card, the card really does
816  * not retry transactions.
817  *
818  * Some uses of this register have mentioned "interference" with
819  * a CPU's "C3 sleep state."  It seems to me that if a bus master
820  * is properly put to sleep, it will neither initiate new transactions,
821  * nor retry delayed transactions, so disabling retries should not
822  * be necessary.
823  *
824  * [1] The timeout does not appear to be documented in any PCI
825  * standard, and we have no documentation of it for the devices by
826  * Atheros, and others, that supposedly implement it.
827  */
828 void
829 pci_disable_retry(pci_chipset_tag_t pc, pcitag_t tag)
830 {
831 #if 0
832 	pcireg_t retry;
833 
834 	/*
835 	 * Disable retry timeout to keep PCI Tx retries from
836 	 * interfering with ACPI C3 CPU state.
837 	 */
838 	retry = pci_conf_read(pc, tag, PCI_RETRY_TIMEOUT_REG);
839 	retry &= ~PCI_RETRY_TIMEOUT_REG_MASK;
840 	pci_conf_write(pc, tag, PCI_RETRY_TIMEOUT_REG, retry);
841 #endif
842 }
843 
844 struct pci_child_power {
845 	struct pci_conf_state p_pciconf;
846 	pci_chipset_tag_t p_pc;
847 	pcitag_t p_tag;
848 	bool p_has_pm;
849 	int p_pm_offset;
850 	pcireg_t p_pm_cap;
851 	pcireg_t p_class;
852 };
853 
854 static bool
855 pci_child_suspend(device_t dv PMF_FN_ARGS)
856 {
857 	struct pci_child_power *priv = device_pmf_bus_private(dv);
858 	pcireg_t ocsr, csr;
859 
860 	pci_conf_capture(priv->p_pc, priv->p_tag, &priv->p_pciconf);
861 
862 	if (!priv->p_has_pm)
863 		return true; /* ??? hopefully handled by ACPI */
864 	if (PCI_CLASS(priv->p_class) == PCI_CLASS_DISPLAY)
865 		return true; /* XXX */
866 
867 	/* disable decoding and busmastering, see pcipm1.2 ch. 8.2.1 */
868 	ocsr = pci_conf_read(priv->p_pc, priv->p_tag, PCI_COMMAND_STATUS_REG);
869 	csr = ocsr & ~(PCI_COMMAND_IO_ENABLE | PCI_COMMAND_MEM_ENABLE
870 		       | PCI_COMMAND_MASTER_ENABLE);
871 	pci_conf_write(priv->p_pc, priv->p_tag, PCI_COMMAND_STATUS_REG, csr);
872 	if (pci_set_powerstate_int(priv->p_pc, priv->p_tag,
873 	    PCI_PMCSR_STATE_D3, priv->p_pm_offset, priv->p_pm_cap)) {
874 		pci_conf_write(priv->p_pc, priv->p_tag,
875 			       PCI_COMMAND_STATUS_REG, ocsr);
876 		aprint_error_dev(dv, "unsupported state, continuing.\n");
877 		return false;
878 	}
879 	return true;
880 }
881 
882 static bool
883 pci_child_resume(device_t dv PMF_FN_ARGS)
884 {
885 	struct pci_child_power *priv = device_pmf_bus_private(dv);
886 
887 	if (priv->p_has_pm &&
888 	    pci_set_powerstate_int(priv->p_pc, priv->p_tag,
889 	    PCI_PMCSR_STATE_D0, priv->p_pm_offset, priv->p_pm_cap)) {
890 		aprint_error_dev(dv, "unsupported state, continuing.\n");
891 		return false;
892 	}
893 
894 	pci_conf_restore(priv->p_pc, priv->p_tag, &priv->p_pciconf);
895 
896 	return true;
897 }
898 
899 static bool
900 pci_child_shutdown(device_t dv, int how)
901 {
902 	struct pci_child_power *priv = device_pmf_bus_private(dv);
903 	pcireg_t csr;
904 
905 	/* disable busmastering */
906 	csr = pci_conf_read(priv->p_pc, priv->p_tag, PCI_COMMAND_STATUS_REG);
907 	csr &= ~PCI_COMMAND_MASTER_ENABLE;
908 	pci_conf_write(priv->p_pc, priv->p_tag, PCI_COMMAND_STATUS_REG, csr);
909 	return true;
910 }
911 
912 static void
913 pci_child_deregister(device_t dv)
914 {
915 	struct pci_child_power *priv = device_pmf_bus_private(dv);
916 
917 	free(priv, M_DEVBUF);
918 }
919 
920 static bool
921 pci_child_register(device_t child)
922 {
923 	device_t self = device_parent(child);
924 	struct pci_softc *sc = device_private(self);
925 	struct pci_child_power *priv;
926 	int device, function, off;
927 	pcireg_t reg;
928 
929 	priv = malloc(sizeof(*priv), M_DEVBUF, M_WAITOK);
930 
931 	device = device_locator(child, PCICF_DEV);
932 	function = device_locator(child, PCICF_FUNCTION);
933 
934 	priv->p_pc = sc->sc_pc;
935 	priv->p_tag = pci_make_tag(priv->p_pc, sc->sc_bus, device,
936 	    function);
937 	priv->p_class = pci_conf_read(priv->p_pc, priv->p_tag, PCI_CLASS_REG);
938 
939 	if (pci_get_capability(priv->p_pc, priv->p_tag,
940 			       PCI_CAP_PWRMGMT, &off, &reg)) {
941 		priv->p_has_pm = true;
942 		priv->p_pm_offset = off;
943 		priv->p_pm_cap = reg;
944 	} else {
945 		priv->p_has_pm = false;
946 		priv->p_pm_offset = -1;
947 	}
948 
949 	device_pmf_bus_register(child, priv, pci_child_suspend,
950 	    pci_child_resume, pci_child_shutdown, pci_child_deregister);
951 
952 	return true;
953 }
954