xref: /freebsd/sys/dev/pci/vga_pci.c (revision f3c5273d315a64826d2149ac453ff8c4583ddbe8)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2005 John Baldwin <jhb@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 /*
33  * Simple driver for PCI VGA display devices.  Drivers such as agp(4) and
34  * drm(4) should attach as children of this device.
35  *
36  * XXX: The vgapci name is a hack until we somehow merge the isa vga driver
37  * in or rename it.
38  */
39 
40 #include <sys/param.h>
41 #include <sys/bus.h>
42 #include <sys/kernel.h>
43 #include <sys/module.h>
44 #include <sys/rman.h>
45 #include <sys/sysctl.h>
46 #include <sys/systm.h>
47 
48 #if defined(__amd64__) || defined(__i386__)
49 #include <vm/vm.h>
50 #include <vm/pmap.h>
51 #endif
52 
53 #include <dev/pci/pcireg.h>
54 #include <dev/pci/pcivar.h>
55 
56 #include <compat/x86bios/x86bios.h> /* To re-POST the card. */
57 
58 struct vga_resource {
59 	struct resource	*vr_res;
60 	int	vr_refs;
61 };
62 
63 struct vga_pci_softc {
64 	device_t	vga_msi_child;	/* Child driver using MSI. */
65 	struct vga_resource vga_bars[PCIR_MAX_BAR_0 + 1];
66 	struct vga_resource vga_bios;
67 };
68 
69 SYSCTL_DECL(_hw_pci);
70 
71 static struct vga_resource *lookup_res(struct vga_pci_softc *sc, int rid);
72 static struct resource *vga_pci_alloc_resource(device_t dev, device_t child,
73     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count,
74     u_int flags);
75 static int	vga_pci_release_resource(device_t dev, device_t child, int type,
76     int rid, struct resource *r);
77 
78 int vga_pci_default_unit = -1;
79 SYSCTL_INT(_hw_pci, OID_AUTO, default_vgapci_unit, CTLFLAG_RDTUN,
80     &vga_pci_default_unit, -1, "Default VGA-compatible display");
81 
82 int
83 vga_pci_is_boot_display(device_t dev)
84 {
85 	int unit;
86 	device_t pcib;
87 	uint16_t config;
88 
89 	/* Check that the given device is a video card */
90 	if ((pci_get_class(dev) != PCIC_DISPLAY &&
91 	    (pci_get_class(dev) != PCIC_OLD ||
92 	     pci_get_subclass(dev) != PCIS_OLD_VGA)))
93 		return (0);
94 
95 	unit = device_get_unit(dev);
96 
97 	if (vga_pci_default_unit >= 0) {
98 		/*
99 		 * The boot display device was determined by a previous
100 		 * call to this function, or the user forced it using
101 		 * the hw.pci.default_vgapci_unit tunable.
102 		 */
103 		return (vga_pci_default_unit == unit);
104 	}
105 
106 	/*
107 	 * The primary video card used as a boot display must have the
108 	 * "I/O" and "Memory Address Space Decoding" bits set in its
109 	 * Command register.
110 	 *
111 	 * Furthermore, if the card is attached to a bridge, instead of
112 	 * the root PCI bus, the bridge must have the "VGA Enable" bit
113 	 * set in its Control register.
114 	 */
115 
116 	pcib = device_get_parent(device_get_parent(dev));
117 	if (device_get_devclass(device_get_parent(pcib)) ==
118 	    devclass_find("pci")) {
119 		/*
120 		 * The parent bridge is a PCI-to-PCI bridge: check the
121 		 * value of the "VGA Enable" bit.
122 		 */
123 		config = pci_read_config(pcib, PCIR_BRIDGECTL_1, 2);
124 		if ((config & PCIB_BCR_VGA_ENABLE) == 0)
125 			return (0);
126 	}
127 
128 	config = pci_read_config(dev, PCIR_COMMAND, 2);
129 	if ((config & (PCIM_CMD_PORTEN | PCIM_CMD_MEMEN)) == 0)
130 		return (0);
131 
132 	/*
133 	 * Disable interrupts until a chipset driver is loaded for
134 	 * this PCI device. Else unhandled display adapter interrupts
135 	 * might freeze the CPU.
136 	 */
137 	pci_write_config(dev, PCIR_COMMAND, config | PCIM_CMD_INTxDIS, 2);
138 
139 	/* This video card is the boot display: record its unit number. */
140 	vga_pci_default_unit = unit;
141 	device_set_flags(dev, 1);
142 
143 	return (1);
144 }
145 
146 void *
147 vga_pci_map_bios(device_t dev, size_t *size)
148 {
149 	int rid;
150 	struct resource *res;
151 
152 #if defined(__amd64__) || defined(__i386__)
153 	if (vga_pci_is_boot_display(dev)) {
154 		/*
155 		 * On x86, the System BIOS copy the default display
156 		 * device's Video BIOS at a fixed location in system
157 		 * memory (0xC0000, 128 kBytes long) at boot time.
158 		 *
159 		 * We use this copy for the default boot device, because
160 		 * the original ROM may not be valid after boot.
161 		 */
162 
163 		*size = VGA_PCI_BIOS_SHADOW_SIZE;
164 		return (pmap_mapbios(VGA_PCI_BIOS_SHADOW_ADDR, *size));
165 	}
166 #endif
167 
168 	rid = PCIR_BIOS;
169 	res = vga_pci_alloc_resource(dev, NULL, SYS_RES_MEMORY, &rid, 0,
170 	    ~0, 1, RF_ACTIVE);
171 	if (res == NULL) {
172 		return (NULL);
173 	}
174 
175 	*size = rman_get_size(res);
176 	return (rman_get_virtual(res));
177 }
178 
179 void
180 vga_pci_unmap_bios(device_t dev, void *bios)
181 {
182 	struct vga_resource *vr;
183 
184 	if (bios == NULL) {
185 		return;
186 	}
187 
188 #if defined(__amd64__) || defined(__i386__)
189 	if (vga_pci_is_boot_display(dev)) {
190 		/* We mapped the BIOS shadow copy located at 0xC0000. */
191 		pmap_unmapdev((vm_offset_t)bios, VGA_PCI_BIOS_SHADOW_SIZE);
192 
193 		return;
194 	}
195 #endif
196 
197 	/*
198 	 * Look up the PCIR_BIOS resource in our softc.  It should match
199 	 * the address we returned previously.
200 	 */
201 	vr = lookup_res(device_get_softc(dev), PCIR_BIOS);
202 	KASSERT(vr->vr_res != NULL, ("vga_pci_unmap_bios: bios not mapped"));
203 	KASSERT(rman_get_virtual(vr->vr_res) == bios,
204 	    ("vga_pci_unmap_bios: mismatch"));
205 	vga_pci_release_resource(dev, NULL, SYS_RES_MEMORY, PCIR_BIOS,
206 	    vr->vr_res);
207 }
208 
209 int
210 vga_pci_repost(device_t dev)
211 {
212 #if defined(__amd64__) || defined(__i386__)
213 	x86regs_t regs;
214 
215 	if (!vga_pci_is_boot_display(dev))
216 		return (EINVAL);
217 
218 	if (x86bios_get_orm(VGA_PCI_BIOS_SHADOW_ADDR) == NULL)
219 		return (ENOTSUP);
220 
221 	x86bios_init_regs(&regs);
222 
223 	regs.R_AH = pci_get_bus(dev);
224 	regs.R_AL = (pci_get_slot(dev) << 3) | (pci_get_function(dev) & 0x07);
225 	regs.R_DL = 0x80;
226 
227 	device_printf(dev, "REPOSTing\n");
228 	x86bios_call(&regs, X86BIOS_PHYSTOSEG(VGA_PCI_BIOS_SHADOW_ADDR + 3),
229 	    X86BIOS_PHYSTOOFF(VGA_PCI_BIOS_SHADOW_ADDR + 3));
230 
231 	x86bios_get_intr(0x10);
232 
233 	return (0);
234 #else
235 	return (ENOTSUP);
236 #endif
237 }
238 
239 static int
240 vga_pci_probe(device_t dev)
241 {
242 
243 	switch (pci_get_class(dev)) {
244 	case PCIC_DISPLAY:
245 		break;
246 	case PCIC_OLD:
247 		if (pci_get_subclass(dev) != PCIS_OLD_VGA)
248 			return (ENXIO);
249 		break;
250 	default:
251 		return (ENXIO);
252 	}
253 
254 	/* Probe default display. */
255 	vga_pci_is_boot_display(dev);
256 
257 	device_set_desc(dev, "VGA-compatible display");
258 	return (BUS_PROBE_GENERIC);
259 }
260 
261 static int
262 vga_pci_attach(device_t dev)
263 {
264 
265 	bus_generic_probe(dev);
266 
267 	/* Always create a drm child for now to make it easier on drm. */
268 	device_add_child(dev, "drm", -1);
269 	device_add_child(dev, "drmn", -1);
270 	bus_generic_attach(dev);
271 
272 	if (vga_pci_is_boot_display(dev))
273 		device_printf(dev, "Boot video device\n");
274 
275 	return (0);
276 }
277 
278 static int
279 vga_pci_suspend(device_t dev)
280 {
281 
282 	return (bus_generic_suspend(dev));
283 }
284 
285 static int
286 vga_pci_detach(device_t dev)
287 {
288 	int error;
289 
290 	error = bus_generic_detach(dev);
291 	if (error == 0)
292 		error = device_delete_children(dev);
293 	return (error);
294 }
295 
296 static int
297 vga_pci_resume(device_t dev)
298 {
299 
300 	return (bus_generic_resume(dev));
301 }
302 
303 /* Bus interface. */
304 
305 static int
306 vga_pci_read_ivar(device_t dev, device_t child, int which, uintptr_t *result)
307 {
308 
309 	return (BUS_READ_IVAR(device_get_parent(dev), dev, which, result));
310 }
311 
312 static int
313 vga_pci_write_ivar(device_t dev, device_t child, int which, uintptr_t value)
314 {
315 
316 	return (EINVAL);
317 }
318 
319 static int
320 vga_pci_setup_intr(device_t dev, device_t child, struct resource *irq,
321     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
322     void **cookiep)
323 {
324 	return (BUS_SETUP_INTR(device_get_parent(dev), dev, irq, flags,
325 	    filter, intr, arg, cookiep));
326 }
327 
328 static int
329 vga_pci_teardown_intr(device_t dev, device_t child, struct resource *irq,
330     void *cookie)
331 {
332 	return (BUS_TEARDOWN_INTR(device_get_parent(dev), dev, irq, cookie));
333 }
334 
335 static struct vga_resource *
336 lookup_res(struct vga_pci_softc *sc, int rid)
337 {
338 	int bar;
339 
340 	if (rid == PCIR_BIOS)
341 		return (&sc->vga_bios);
342 	bar = PCI_RID2BAR(rid);
343 	if (bar >= 0 && bar <= PCIR_MAX_BAR_0)
344 		return (&sc->vga_bars[bar]);
345 	return (NULL);
346 }
347 
348 static struct resource *
349 vga_pci_alloc_resource(device_t dev, device_t child, int type, int *rid,
350     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
351 {
352 	struct vga_resource *vr;
353 
354 	switch (type) {
355 	case SYS_RES_MEMORY:
356 	case SYS_RES_IOPORT:
357 		/*
358 		 * For BARs, we cache the resource so that we only allocate it
359 		 * from the PCI bus once.
360 		 */
361 		vr = lookup_res(device_get_softc(dev), *rid);
362 		if (vr == NULL)
363 			return (NULL);
364 		if (vr->vr_res == NULL)
365 			vr->vr_res = bus_alloc_resource(dev, type, rid, start,
366 			    end, count, flags);
367 		if (vr->vr_res != NULL)
368 			vr->vr_refs++;
369 		return (vr->vr_res);
370 	}
371 	return (bus_alloc_resource(dev, type, rid, start, end, count, flags));
372 }
373 
374 static int
375 vga_pci_release_resource(device_t dev, device_t child, int type, int rid,
376     struct resource *r)
377 {
378 	struct vga_resource *vr;
379 	int error;
380 
381 	switch (type) {
382 	case SYS_RES_MEMORY:
383 	case SYS_RES_IOPORT:
384 		/*
385 		 * For BARs, we release the resource from the PCI bus
386 		 * when the last child reference goes away.
387 		 */
388 		vr = lookup_res(device_get_softc(dev), rid);
389 		if (vr == NULL)
390 			return (EINVAL);
391 		if (vr->vr_res == NULL)
392 			return (EINVAL);
393 		KASSERT(vr->vr_res == r, ("vga_pci resource mismatch"));
394 		if (vr->vr_refs > 1) {
395 			vr->vr_refs--;
396 			return (0);
397 		}
398 		KASSERT(vr->vr_refs > 0,
399 		    ("vga_pci resource reference count underflow"));
400 		error = bus_release_resource(dev, type, rid, r);
401 		if (error == 0) {
402 			vr->vr_res = NULL;
403 			vr->vr_refs = 0;
404 		}
405 		return (error);
406 	}
407 
408 	return (bus_release_resource(dev, type, rid, r));
409 }
410 
411 /* PCI interface. */
412 
413 static uint32_t
414 vga_pci_read_config(device_t dev, device_t child, int reg, int width)
415 {
416 
417 	return (pci_read_config(dev, reg, width));
418 }
419 
420 static void
421 vga_pci_write_config(device_t dev, device_t child, int reg,
422     uint32_t val, int width)
423 {
424 
425 	pci_write_config(dev, reg, val, width);
426 }
427 
428 static int
429 vga_pci_enable_busmaster(device_t dev, device_t child)
430 {
431 
432 	return (pci_enable_busmaster(dev));
433 }
434 
435 static int
436 vga_pci_disable_busmaster(device_t dev, device_t child)
437 {
438 
439 	return (pci_disable_busmaster(dev));
440 }
441 
442 static int
443 vga_pci_enable_io(device_t dev, device_t child, int space)
444 {
445 
446 	device_printf(dev, "child %s requested pci_enable_io\n",
447 	    device_get_nameunit(child));
448 	return (pci_enable_io(dev, space));
449 }
450 
451 static int
452 vga_pci_disable_io(device_t dev, device_t child, int space)
453 {
454 
455 	device_printf(dev, "child %s requested pci_disable_io\n",
456 	    device_get_nameunit(child));
457 	return (pci_disable_io(dev, space));
458 }
459 
460 static int
461 vga_pci_get_vpd_ident(device_t dev, device_t child, const char **identptr)
462 {
463 
464 	return (pci_get_vpd_ident(dev, identptr));
465 }
466 
467 static int
468 vga_pci_get_vpd_readonly(device_t dev, device_t child, const char *kw,
469     const char **vptr)
470 {
471 
472 	return (pci_get_vpd_readonly(dev, kw, vptr));
473 }
474 
475 static int
476 vga_pci_set_powerstate(device_t dev, device_t child, int state)
477 {
478 
479 	device_printf(dev, "child %s requested pci_set_powerstate\n",
480 	    device_get_nameunit(child));
481 	return (pci_set_powerstate(dev, state));
482 }
483 
484 static int
485 vga_pci_get_powerstate(device_t dev, device_t child)
486 {
487 
488 	device_printf(dev, "child %s requested pci_get_powerstate\n",
489 	    device_get_nameunit(child));
490 	return (pci_get_powerstate(dev));
491 }
492 
493 static int
494 vga_pci_assign_interrupt(device_t dev, device_t child)
495 {
496 
497 	device_printf(dev, "child %s requested pci_assign_interrupt\n",
498 	    device_get_nameunit(child));
499 	return (PCI_ASSIGN_INTERRUPT(device_get_parent(dev), dev));
500 }
501 
502 static int
503 vga_pci_find_cap(device_t dev, device_t child, int capability,
504     int *capreg)
505 {
506 
507 	return (pci_find_cap(dev, capability, capreg));
508 }
509 
510 static int
511 vga_pci_find_next_cap(device_t dev, device_t child, int capability,
512     int start, int *capreg)
513 {
514 
515 	return (pci_find_next_cap(dev, capability, start, capreg));
516 }
517 
518 static int
519 vga_pci_find_extcap(device_t dev, device_t child, int capability,
520     int *capreg)
521 {
522 
523 	return (pci_find_extcap(dev, capability, capreg));
524 }
525 
526 static int
527 vga_pci_find_next_extcap(device_t dev, device_t child, int capability,
528     int start, int *capreg)
529 {
530 
531 	return (pci_find_next_extcap(dev, capability, start, capreg));
532 }
533 
534 static int
535 vga_pci_find_htcap(device_t dev, device_t child, int capability,
536     int *capreg)
537 {
538 
539 	return (pci_find_htcap(dev, capability, capreg));
540 }
541 
542 static int
543 vga_pci_find_next_htcap(device_t dev, device_t child, int capability,
544     int start, int *capreg)
545 {
546 
547 	return (pci_find_next_htcap(dev, capability, start, capreg));
548 }
549 
550 static int
551 vga_pci_alloc_msi(device_t dev, device_t child, int *count)
552 {
553 	struct vga_pci_softc *sc;
554 	int error;
555 
556 	sc = device_get_softc(dev);
557 	if (sc->vga_msi_child != NULL)
558 		return (EBUSY);
559 	error = pci_alloc_msi(dev, count);
560 	if (error == 0)
561 		sc->vga_msi_child = child;
562 	return (error);
563 }
564 
565 static int
566 vga_pci_alloc_msix(device_t dev, device_t child, int *count)
567 {
568 	struct vga_pci_softc *sc;
569 	int error;
570 
571 	sc = device_get_softc(dev);
572 	if (sc->vga_msi_child != NULL)
573 		return (EBUSY);
574 	error = pci_alloc_msix(dev, count);
575 	if (error == 0)
576 		sc->vga_msi_child = child;
577 	return (error);
578 }
579 
580 static int
581 vga_pci_remap_msix(device_t dev, device_t child, int count,
582     const u_int *vectors)
583 {
584 	struct vga_pci_softc *sc;
585 
586 	sc = device_get_softc(dev);
587 	if (sc->vga_msi_child != child)
588 		return (ENXIO);
589 	return (pci_remap_msix(dev, count, vectors));
590 }
591 
592 static int
593 vga_pci_release_msi(device_t dev, device_t child)
594 {
595 	struct vga_pci_softc *sc;
596 	int error;
597 
598 	sc = device_get_softc(dev);
599 	if (sc->vga_msi_child != child)
600 		return (ENXIO);
601 	error = pci_release_msi(dev);
602 	if (error == 0)
603 		sc->vga_msi_child = NULL;
604 	return (error);
605 }
606 
607 static int
608 vga_pci_msi_count(device_t dev, device_t child)
609 {
610 
611 	return (pci_msi_count(dev));
612 }
613 
614 static int
615 vga_pci_msix_count(device_t dev, device_t child)
616 {
617 
618 	return (pci_msix_count(dev));
619 }
620 
621 static bus_dma_tag_t
622 vga_pci_get_dma_tag(device_t bus, device_t child)
623 {
624 
625 	return (bus_get_dma_tag(bus));
626 }
627 
628 static device_method_t vga_pci_methods[] = {
629 	/* Device interface */
630 	DEVMETHOD(device_probe,		vga_pci_probe),
631 	DEVMETHOD(device_attach,	vga_pci_attach),
632 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
633 	DEVMETHOD(device_suspend,	vga_pci_suspend),
634 	DEVMETHOD(device_detach,	vga_pci_detach),
635 	DEVMETHOD(device_resume,	vga_pci_resume),
636 
637 	/* Bus interface */
638 	DEVMETHOD(bus_read_ivar,	vga_pci_read_ivar),
639 	DEVMETHOD(bus_write_ivar,	vga_pci_write_ivar),
640 	DEVMETHOD(bus_setup_intr,	vga_pci_setup_intr),
641 	DEVMETHOD(bus_teardown_intr,	vga_pci_teardown_intr),
642 	DEVMETHOD(bus_alloc_resource,	vga_pci_alloc_resource),
643 	DEVMETHOD(bus_release_resource,	vga_pci_release_resource),
644 	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
645 	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
646 	DEVMETHOD(bus_get_dma_tag,	vga_pci_get_dma_tag),
647 
648 	/* PCI interface */
649 	DEVMETHOD(pci_read_config,	vga_pci_read_config),
650 	DEVMETHOD(pci_write_config,	vga_pci_write_config),
651 	DEVMETHOD(pci_enable_busmaster,	vga_pci_enable_busmaster),
652 	DEVMETHOD(pci_disable_busmaster, vga_pci_disable_busmaster),
653 	DEVMETHOD(pci_enable_io,	vga_pci_enable_io),
654 	DEVMETHOD(pci_disable_io,	vga_pci_disable_io),
655 	DEVMETHOD(pci_get_vpd_ident,	vga_pci_get_vpd_ident),
656 	DEVMETHOD(pci_get_vpd_readonly,	vga_pci_get_vpd_readonly),
657 	DEVMETHOD(pci_get_powerstate,	vga_pci_get_powerstate),
658 	DEVMETHOD(pci_set_powerstate,	vga_pci_set_powerstate),
659 	DEVMETHOD(pci_assign_interrupt,	vga_pci_assign_interrupt),
660 	DEVMETHOD(pci_find_cap,		vga_pci_find_cap),
661 	DEVMETHOD(pci_find_next_cap,	vga_pci_find_next_cap),
662 	DEVMETHOD(pci_find_extcap,	vga_pci_find_extcap),
663 	DEVMETHOD(pci_find_next_extcap,	vga_pci_find_next_extcap),
664 	DEVMETHOD(pci_find_htcap,	vga_pci_find_htcap),
665 	DEVMETHOD(pci_find_next_htcap,	vga_pci_find_next_htcap),
666 	DEVMETHOD(pci_alloc_msi,	vga_pci_alloc_msi),
667 	DEVMETHOD(pci_alloc_msix,	vga_pci_alloc_msix),
668 	DEVMETHOD(pci_remap_msix,	vga_pci_remap_msix),
669 	DEVMETHOD(pci_release_msi,	vga_pci_release_msi),
670 	DEVMETHOD(pci_msi_count,	vga_pci_msi_count),
671 	DEVMETHOD(pci_msix_count,	vga_pci_msix_count),
672 
673 	{ 0, 0 }
674 };
675 
676 static driver_t vga_pci_driver = {
677 	"vgapci",
678 	vga_pci_methods,
679 	sizeof(struct vga_pci_softc),
680 };
681 
682 static devclass_t vga_devclass;
683 
684 DRIVER_MODULE(vgapci, pci, vga_pci_driver, vga_devclass, 0, 0);
685 MODULE_DEPEND(vgapci, x86bios, 1, 1, 1);
686