xref: /freebsd/sys/dev/pci/vga_pci.c (revision 3ee5c55415a7b08c6c4c403cc6b96e30d768e1c9)
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_resume(device_t dev)
287 {
288 
289 	return (bus_generic_resume(dev));
290 }
291 
292 /* Bus interface. */
293 
294 static int
295 vga_pci_read_ivar(device_t dev, device_t child, int which, uintptr_t *result)
296 {
297 
298 	return (BUS_READ_IVAR(device_get_parent(dev), dev, which, result));
299 }
300 
301 static int
302 vga_pci_write_ivar(device_t dev, device_t child, int which, uintptr_t value)
303 {
304 
305 	return (EINVAL);
306 }
307 
308 static int
309 vga_pci_setup_intr(device_t dev, device_t child, struct resource *irq,
310     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
311     void **cookiep)
312 {
313 	return (BUS_SETUP_INTR(device_get_parent(dev), dev, irq, flags,
314 	    filter, intr, arg, cookiep));
315 }
316 
317 static int
318 vga_pci_teardown_intr(device_t dev, device_t child, struct resource *irq,
319     void *cookie)
320 {
321 	return (BUS_TEARDOWN_INTR(device_get_parent(dev), dev, irq, cookie));
322 }
323 
324 static struct vga_resource *
325 lookup_res(struct vga_pci_softc *sc, int rid)
326 {
327 	int bar;
328 
329 	if (rid == PCIR_BIOS)
330 		return (&sc->vga_bios);
331 	bar = PCI_RID2BAR(rid);
332 	if (bar >= 0 && bar <= PCIR_MAX_BAR_0)
333 		return (&sc->vga_bars[bar]);
334 	return (NULL);
335 }
336 
337 static struct resource *
338 vga_pci_alloc_resource(device_t dev, device_t child, int type, int *rid,
339     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
340 {
341 	struct vga_resource *vr;
342 
343 	switch (type) {
344 	case SYS_RES_MEMORY:
345 	case SYS_RES_IOPORT:
346 		/*
347 		 * For BARs, we cache the resource so that we only allocate it
348 		 * from the PCI bus once.
349 		 */
350 		vr = lookup_res(device_get_softc(dev), *rid);
351 		if (vr == NULL)
352 			return (NULL);
353 		if (vr->vr_res == NULL)
354 			vr->vr_res = bus_alloc_resource(dev, type, rid, start,
355 			    end, count, flags);
356 		if (vr->vr_res != NULL)
357 			vr->vr_refs++;
358 		return (vr->vr_res);
359 	}
360 	return (bus_alloc_resource(dev, type, rid, start, end, count, flags));
361 }
362 
363 static int
364 vga_pci_release_resource(device_t dev, device_t child, int type, int rid,
365     struct resource *r)
366 {
367 	struct vga_resource *vr;
368 	int error;
369 
370 	switch (type) {
371 	case SYS_RES_MEMORY:
372 	case SYS_RES_IOPORT:
373 		/*
374 		 * For BARs, we release the resource from the PCI bus
375 		 * when the last child reference goes away.
376 		 */
377 		vr = lookup_res(device_get_softc(dev), rid);
378 		if (vr == NULL)
379 			return (EINVAL);
380 		if (vr->vr_res == NULL)
381 			return (EINVAL);
382 		KASSERT(vr->vr_res == r, ("vga_pci resource mismatch"));
383 		if (vr->vr_refs > 1) {
384 			vr->vr_refs--;
385 			return (0);
386 		}
387 		KASSERT(vr->vr_refs > 0,
388 		    ("vga_pci resource reference count underflow"));
389 		error = bus_release_resource(dev, type, rid, r);
390 		if (error == 0) {
391 			vr->vr_res = NULL;
392 			vr->vr_refs = 0;
393 		}
394 		return (error);
395 	}
396 
397 	return (bus_release_resource(dev, type, rid, r));
398 }
399 
400 /* PCI interface. */
401 
402 static uint32_t
403 vga_pci_read_config(device_t dev, device_t child, int reg, int width)
404 {
405 
406 	return (pci_read_config(dev, reg, width));
407 }
408 
409 static void
410 vga_pci_write_config(device_t dev, device_t child, int reg,
411     uint32_t val, int width)
412 {
413 
414 	pci_write_config(dev, reg, val, width);
415 }
416 
417 static int
418 vga_pci_enable_busmaster(device_t dev, device_t child)
419 {
420 
421 	return (pci_enable_busmaster(dev));
422 }
423 
424 static int
425 vga_pci_disable_busmaster(device_t dev, device_t child)
426 {
427 
428 	return (pci_disable_busmaster(dev));
429 }
430 
431 static int
432 vga_pci_enable_io(device_t dev, device_t child, int space)
433 {
434 
435 	device_printf(dev, "child %s requested pci_enable_io\n",
436 	    device_get_nameunit(child));
437 	return (pci_enable_io(dev, space));
438 }
439 
440 static int
441 vga_pci_disable_io(device_t dev, device_t child, int space)
442 {
443 
444 	device_printf(dev, "child %s requested pci_disable_io\n",
445 	    device_get_nameunit(child));
446 	return (pci_disable_io(dev, space));
447 }
448 
449 static int
450 vga_pci_get_vpd_ident(device_t dev, device_t child, const char **identptr)
451 {
452 
453 	return (pci_get_vpd_ident(dev, identptr));
454 }
455 
456 static int
457 vga_pci_get_vpd_readonly(device_t dev, device_t child, const char *kw,
458     const char **vptr)
459 {
460 
461 	return (pci_get_vpd_readonly(dev, kw, vptr));
462 }
463 
464 static int
465 vga_pci_set_powerstate(device_t dev, device_t child, int state)
466 {
467 
468 	device_printf(dev, "child %s requested pci_set_powerstate\n",
469 	    device_get_nameunit(child));
470 	return (pci_set_powerstate(dev, state));
471 }
472 
473 static int
474 vga_pci_get_powerstate(device_t dev, device_t child)
475 {
476 
477 	device_printf(dev, "child %s requested pci_get_powerstate\n",
478 	    device_get_nameunit(child));
479 	return (pci_get_powerstate(dev));
480 }
481 
482 static int
483 vga_pci_assign_interrupt(device_t dev, device_t child)
484 {
485 
486 	device_printf(dev, "child %s requested pci_assign_interrupt\n",
487 	    device_get_nameunit(child));
488 	return (PCI_ASSIGN_INTERRUPT(device_get_parent(dev), dev));
489 }
490 
491 static int
492 vga_pci_find_cap(device_t dev, device_t child, int capability,
493     int *capreg)
494 {
495 
496 	return (pci_find_cap(dev, capability, capreg));
497 }
498 
499 static int
500 vga_pci_find_next_cap(device_t dev, device_t child, int capability,
501     int start, int *capreg)
502 {
503 
504 	return (pci_find_next_cap(dev, capability, start, capreg));
505 }
506 
507 static int
508 vga_pci_find_extcap(device_t dev, device_t child, int capability,
509     int *capreg)
510 {
511 
512 	return (pci_find_extcap(dev, capability, capreg));
513 }
514 
515 static int
516 vga_pci_find_next_extcap(device_t dev, device_t child, int capability,
517     int start, int *capreg)
518 {
519 
520 	return (pci_find_next_extcap(dev, capability, start, capreg));
521 }
522 
523 static int
524 vga_pci_find_htcap(device_t dev, device_t child, int capability,
525     int *capreg)
526 {
527 
528 	return (pci_find_htcap(dev, capability, capreg));
529 }
530 
531 static int
532 vga_pci_find_next_htcap(device_t dev, device_t child, int capability,
533     int start, int *capreg)
534 {
535 
536 	return (pci_find_next_htcap(dev, capability, start, capreg));
537 }
538 
539 static int
540 vga_pci_alloc_msi(device_t dev, device_t child, int *count)
541 {
542 	struct vga_pci_softc *sc;
543 	int error;
544 
545 	sc = device_get_softc(dev);
546 	if (sc->vga_msi_child != NULL)
547 		return (EBUSY);
548 	error = pci_alloc_msi(dev, count);
549 	if (error == 0)
550 		sc->vga_msi_child = child;
551 	return (error);
552 }
553 
554 static int
555 vga_pci_alloc_msix(device_t dev, device_t child, int *count)
556 {
557 	struct vga_pci_softc *sc;
558 	int error;
559 
560 	sc = device_get_softc(dev);
561 	if (sc->vga_msi_child != NULL)
562 		return (EBUSY);
563 	error = pci_alloc_msix(dev, count);
564 	if (error == 0)
565 		sc->vga_msi_child = child;
566 	return (error);
567 }
568 
569 static int
570 vga_pci_remap_msix(device_t dev, device_t child, int count,
571     const u_int *vectors)
572 {
573 	struct vga_pci_softc *sc;
574 
575 	sc = device_get_softc(dev);
576 	if (sc->vga_msi_child != child)
577 		return (ENXIO);
578 	return (pci_remap_msix(dev, count, vectors));
579 }
580 
581 static int
582 vga_pci_release_msi(device_t dev, device_t child)
583 {
584 	struct vga_pci_softc *sc;
585 	int error;
586 
587 	sc = device_get_softc(dev);
588 	if (sc->vga_msi_child != child)
589 		return (ENXIO);
590 	error = pci_release_msi(dev);
591 	if (error == 0)
592 		sc->vga_msi_child = NULL;
593 	return (error);
594 }
595 
596 static int
597 vga_pci_msi_count(device_t dev, device_t child)
598 {
599 
600 	return (pci_msi_count(dev));
601 }
602 
603 static int
604 vga_pci_msix_count(device_t dev, device_t child)
605 {
606 
607 	return (pci_msix_count(dev));
608 }
609 
610 static bus_dma_tag_t
611 vga_pci_get_dma_tag(device_t bus, device_t child)
612 {
613 
614 	return (bus_get_dma_tag(bus));
615 }
616 
617 static device_method_t vga_pci_methods[] = {
618 	/* Device interface */
619 	DEVMETHOD(device_probe,		vga_pci_probe),
620 	DEVMETHOD(device_attach,	vga_pci_attach),
621 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
622 	DEVMETHOD(device_suspend,	vga_pci_suspend),
623 	DEVMETHOD(device_resume,	vga_pci_resume),
624 
625 	/* Bus interface */
626 	DEVMETHOD(bus_read_ivar,	vga_pci_read_ivar),
627 	DEVMETHOD(bus_write_ivar,	vga_pci_write_ivar),
628 	DEVMETHOD(bus_setup_intr,	vga_pci_setup_intr),
629 	DEVMETHOD(bus_teardown_intr,	vga_pci_teardown_intr),
630 	DEVMETHOD(bus_alloc_resource,	vga_pci_alloc_resource),
631 	DEVMETHOD(bus_release_resource,	vga_pci_release_resource),
632 	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
633 	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
634 	DEVMETHOD(bus_get_dma_tag,	vga_pci_get_dma_tag),
635 
636 	/* PCI interface */
637 	DEVMETHOD(pci_read_config,	vga_pci_read_config),
638 	DEVMETHOD(pci_write_config,	vga_pci_write_config),
639 	DEVMETHOD(pci_enable_busmaster,	vga_pci_enable_busmaster),
640 	DEVMETHOD(pci_disable_busmaster, vga_pci_disable_busmaster),
641 	DEVMETHOD(pci_enable_io,	vga_pci_enable_io),
642 	DEVMETHOD(pci_disable_io,	vga_pci_disable_io),
643 	DEVMETHOD(pci_get_vpd_ident,	vga_pci_get_vpd_ident),
644 	DEVMETHOD(pci_get_vpd_readonly,	vga_pci_get_vpd_readonly),
645 	DEVMETHOD(pci_get_powerstate,	vga_pci_get_powerstate),
646 	DEVMETHOD(pci_set_powerstate,	vga_pci_set_powerstate),
647 	DEVMETHOD(pci_assign_interrupt,	vga_pci_assign_interrupt),
648 	DEVMETHOD(pci_find_cap,		vga_pci_find_cap),
649 	DEVMETHOD(pci_find_next_cap,	vga_pci_find_next_cap),
650 	DEVMETHOD(pci_find_extcap,	vga_pci_find_extcap),
651 	DEVMETHOD(pci_find_next_extcap,	vga_pci_find_next_extcap),
652 	DEVMETHOD(pci_find_htcap,	vga_pci_find_htcap),
653 	DEVMETHOD(pci_find_next_htcap,	vga_pci_find_next_htcap),
654 	DEVMETHOD(pci_alloc_msi,	vga_pci_alloc_msi),
655 	DEVMETHOD(pci_alloc_msix,	vga_pci_alloc_msix),
656 	DEVMETHOD(pci_remap_msix,	vga_pci_remap_msix),
657 	DEVMETHOD(pci_release_msi,	vga_pci_release_msi),
658 	DEVMETHOD(pci_msi_count,	vga_pci_msi_count),
659 	DEVMETHOD(pci_msix_count,	vga_pci_msix_count),
660 
661 	{ 0, 0 }
662 };
663 
664 static driver_t vga_pci_driver = {
665 	"vgapci",
666 	vga_pci_methods,
667 	sizeof(struct vga_pci_softc),
668 };
669 
670 static devclass_t vga_devclass;
671 
672 DRIVER_MODULE(vgapci, pci, vga_pci_driver, vga_devclass, 0, 0);
673 MODULE_DEPEND(vgapci, x86bios, 1, 1, 1);
674