xref: /freebsd/sys/dev/pci/vga_pci.c (revision a3cbca537ef1d8ac03a693cd51d98fb8087acc8d)
1 /*-
2  * Copyright (c) 2005 John Baldwin <jhb@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 /*
31  * Simple driver for PCI VGA display devices.  Drivers such as agp(4) and
32  * drm(4) should attach as children of this device.
33  *
34  * XXX: The vgapci name is a hack until we somehow merge the isa vga driver
35  * in or rename it.
36  */
37 
38 #include <sys/param.h>
39 #include <sys/bus.h>
40 #include <sys/kernel.h>
41 #include <sys/module.h>
42 #include <sys/rman.h>
43 #include <sys/sysctl.h>
44 #include <sys/systm.h>
45 
46 #if defined(__amd64__) || defined(__i386__)
47 #include <vm/vm.h>
48 #include <vm/pmap.h>
49 #endif
50 
51 #include <dev/pci/pcireg.h>
52 #include <dev/pci/pcivar.h>
53 
54 struct vga_resource {
55 	struct resource	*vr_res;
56 	int	vr_refs;
57 };
58 
59 struct vga_pci_softc {
60 	device_t	vga_msi_child;	/* Child driver using MSI. */
61 	struct vga_resource vga_bars[PCIR_MAX_BAR_0 + 1];
62 	struct vga_resource vga_bios;
63 };
64 
65 SYSCTL_DECL(_hw_pci);
66 
67 static struct vga_resource *lookup_res(struct vga_pci_softc *sc, int rid);
68 static struct resource *vga_pci_alloc_resource(device_t dev, device_t child,
69     int type, int *rid, u_long start, u_long end, u_long count, u_int flags);
70 static int	vga_pci_release_resource(device_t dev, device_t child, int type,
71     int rid, struct resource *r);
72 
73 int vga_pci_default_unit = -1;
74 SYSCTL_INT(_hw_pci, OID_AUTO, default_vgapci_unit, CTLFLAG_RDTUN,
75     &vga_pci_default_unit, -1, "Default VGA-compatible display");
76 
77 int
78 vga_pci_is_boot_display(device_t dev)
79 {
80 	int unit;
81 	device_t pcib;
82 	uint16_t config;
83 
84 	/* Check that the given device is a video card */
85 	if ((pci_get_class(dev) != PCIC_DISPLAY &&
86 	    (pci_get_class(dev) != PCIC_OLD ||
87 	     pci_get_subclass(dev) != PCIS_OLD_VGA)))
88 		return (0);
89 
90 	unit = device_get_unit(dev);
91 
92 	if (vga_pci_default_unit >= 0) {
93 		/*
94 		 * The boot display device was determined by a previous
95 		 * call to this function, or the user forced it using
96 		 * the hw.pci.default_vgapci_unit tunable.
97 		 */
98 		return (vga_pci_default_unit == unit);
99 	}
100 
101 	/*
102 	 * The primary video card used as a boot display must have the
103 	 * "I/O" and "Memory Address Space Decoding" bits set in its
104 	 * Command register.
105 	 *
106 	 * Furthermore, if the card is attached to a bridge, instead of
107 	 * the root PCI bus, the bridge must have the "VGA Enable" bit
108 	 * set in its Control register.
109 	 */
110 
111 	pcib = device_get_parent(device_get_parent(dev));
112 	if (device_get_devclass(device_get_parent(pcib)) ==
113 	    devclass_find("pci")) {
114 		/*
115 		 * The parent bridge is a PCI-to-PCI bridge: check the
116 		 * value of the "VGA Enable" bit.
117 		 */
118 		config = pci_read_config(pcib, PCIR_BRIDGECTL_1, 2);
119 		if ((config & PCIB_BCR_VGA_ENABLE) == 0)
120 			return (0);
121 	}
122 
123 	config = pci_read_config(dev, PCIR_COMMAND, 2);
124 	if ((config & (PCIM_CMD_PORTEN | PCIM_CMD_MEMEN)) == 0)
125 		return (0);
126 
127 	/* This video card is the boot display: record its unit number. */
128 	vga_pci_default_unit = unit;
129 	device_set_flags(dev, 1);
130 
131 	return (1);
132 }
133 
134 void *
135 vga_pci_map_bios(device_t dev, size_t *size)
136 {
137 	int rid;
138 	struct resource *res;
139 
140 #if defined(__amd64__) || defined(__i386__)
141 	if (vga_pci_is_boot_display(dev)) {
142 		/*
143 		 * On x86, the System BIOS copy the default display
144 		 * device's Video BIOS at a fixed location in system
145 		 * memory (0xC0000, 128 kBytes long) at boot time.
146 		 *
147 		 * We use this copy for the default boot device, because
148 		 * the original ROM may not be valid after boot.
149 		 */
150 
151 		*size = VGA_PCI_BIOS_SHADOW_SIZE;
152 		return (pmap_mapbios(VGA_PCI_BIOS_SHADOW_ADDR, *size));
153 	}
154 #endif
155 
156 	rid = PCIR_BIOS;
157 	res = vga_pci_alloc_resource(dev, NULL, SYS_RES_MEMORY, &rid, 0ul,
158 	    ~0ul, 1, RF_ACTIVE);
159 	if (res == NULL) {
160 		return (NULL);
161 	}
162 
163 	*size = rman_get_size(res);
164 	return (rman_get_virtual(res));
165 }
166 
167 void
168 vga_pci_unmap_bios(device_t dev, void *bios)
169 {
170 	struct vga_resource *vr;
171 
172 	if (bios == NULL) {
173 		return;
174 	}
175 
176 #if defined(__amd64__) || defined(__i386__)
177 	if (vga_pci_is_boot_display(dev)) {
178 		/* We mapped the BIOS shadow copy located at 0xC0000. */
179 		pmap_unmapdev((vm_offset_t)bios, VGA_PCI_BIOS_SHADOW_SIZE);
180 
181 		return;
182 	}
183 #endif
184 
185 	/*
186 	 * Look up the PCIR_BIOS resource in our softc.  It should match
187 	 * the address we returned previously.
188 	 */
189 	vr = lookup_res(device_get_softc(dev), PCIR_BIOS);
190 	KASSERT(vr->vr_res != NULL, ("vga_pci_unmap_bios: bios not mapped"));
191 	KASSERT(rman_get_virtual(vr->vr_res) == bios,
192 	    ("vga_pci_unmap_bios: mismatch"));
193 	vga_pci_release_resource(dev, NULL, SYS_RES_MEMORY, PCIR_BIOS,
194 	    vr->vr_res);
195 }
196 
197 static int
198 vga_pci_probe(device_t dev)
199 {
200 
201 	switch (pci_get_class(dev)) {
202 	case PCIC_DISPLAY:
203 		break;
204 	case PCIC_OLD:
205 		if (pci_get_subclass(dev) != PCIS_OLD_VGA)
206 			return (ENXIO);
207 		break;
208 	default:
209 		return (ENXIO);
210 	}
211 
212 	/* Probe default display. */
213 	vga_pci_is_boot_display(dev);
214 
215 	device_set_desc(dev, "VGA-compatible display");
216 	return (BUS_PROBE_GENERIC);
217 }
218 
219 static int
220 vga_pci_attach(device_t dev)
221 {
222 
223 	bus_generic_probe(dev);
224 
225 	/* Always create a drm child for now to make it easier on drm. */
226 	device_add_child(dev, "drm", -1);
227 	device_add_child(dev, "drmn", -1);
228 	bus_generic_attach(dev);
229 
230 	if (vga_pci_is_boot_display(dev))
231 		device_printf(dev, "Boot video device\n");
232 
233 	return (0);
234 }
235 
236 static int
237 vga_pci_suspend(device_t dev)
238 {
239 
240 	return (bus_generic_suspend(dev));
241 }
242 
243 static int
244 vga_pci_resume(device_t dev)
245 {
246 
247 	return (bus_generic_resume(dev));
248 }
249 
250 /* Bus interface. */
251 
252 static int
253 vga_pci_read_ivar(device_t dev, device_t child, int which, uintptr_t *result)
254 {
255 
256 	return (BUS_READ_IVAR(device_get_parent(dev), dev, which, result));
257 }
258 
259 static int
260 vga_pci_write_ivar(device_t dev, device_t child, int which, uintptr_t value)
261 {
262 
263 	return (EINVAL);
264 }
265 
266 static int
267 vga_pci_setup_intr(device_t dev, device_t child, struct resource *irq,
268     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
269     void **cookiep)
270 {
271 	return (BUS_SETUP_INTR(device_get_parent(dev), dev, irq, flags,
272 	    filter, intr, arg, cookiep));
273 }
274 
275 static int
276 vga_pci_teardown_intr(device_t dev, device_t child, struct resource *irq,
277     void *cookie)
278 {
279 	return (BUS_TEARDOWN_INTR(device_get_parent(dev), dev, irq, cookie));
280 }
281 
282 static struct vga_resource *
283 lookup_res(struct vga_pci_softc *sc, int rid)
284 {
285 	int bar;
286 
287 	if (rid == PCIR_BIOS)
288 		return (&sc->vga_bios);
289 	bar = PCI_RID2BAR(rid);
290 	if (bar >= 0 && bar <= PCIR_MAX_BAR_0)
291 		return (&sc->vga_bars[bar]);
292 	return (NULL);
293 }
294 
295 static struct resource *
296 vga_pci_alloc_resource(device_t dev, device_t child, int type, int *rid,
297     u_long start, u_long end, u_long count, u_int flags)
298 {
299 	struct vga_resource *vr;
300 
301 	switch (type) {
302 	case SYS_RES_MEMORY:
303 	case SYS_RES_IOPORT:
304 		/*
305 		 * For BARs, we cache the resource so that we only allocate it
306 		 * from the PCI bus once.
307 		 */
308 		vr = lookup_res(device_get_softc(dev), *rid);
309 		if (vr == NULL)
310 			return (NULL);
311 		if (vr->vr_res == NULL)
312 			vr->vr_res = bus_alloc_resource(dev, type, rid, start,
313 			    end, count, flags);
314 		if (vr->vr_res != NULL)
315 			vr->vr_refs++;
316 		return (vr->vr_res);
317 	}
318 	return (bus_alloc_resource(dev, type, rid, start, end, count, flags));
319 }
320 
321 static int
322 vga_pci_release_resource(device_t dev, device_t child, int type, int rid,
323     struct resource *r)
324 {
325 	struct vga_resource *vr;
326 	int error;
327 
328 	switch (type) {
329 	case SYS_RES_MEMORY:
330 	case SYS_RES_IOPORT:
331 		/*
332 		 * For BARs, we release the resource from the PCI bus
333 		 * when the last child reference goes away.
334 		 */
335 		vr = lookup_res(device_get_softc(dev), rid);
336 		if (vr == NULL)
337 			return (EINVAL);
338 		if (vr->vr_res == NULL)
339 			return (EINVAL);
340 		KASSERT(vr->vr_res == r, ("vga_pci resource mismatch"));
341 		if (vr->vr_refs > 1) {
342 			vr->vr_refs--;
343 			return (0);
344 		}
345 		KASSERT(vr->vr_refs > 0,
346 		    ("vga_pci resource reference count underflow"));
347 		error = bus_release_resource(dev, type, rid, r);
348 		if (error == 0) {
349 			vr->vr_res = NULL;
350 			vr->vr_refs = 0;
351 		}
352 		return (error);
353 	}
354 
355 	return (bus_release_resource(dev, type, rid, r));
356 }
357 
358 /* PCI interface. */
359 
360 static uint32_t
361 vga_pci_read_config(device_t dev, device_t child, int reg, int width)
362 {
363 
364 	return (pci_read_config(dev, reg, width));
365 }
366 
367 static void
368 vga_pci_write_config(device_t dev, device_t child, int reg,
369     uint32_t val, int width)
370 {
371 
372 	pci_write_config(dev, reg, val, width);
373 }
374 
375 static int
376 vga_pci_enable_busmaster(device_t dev, device_t child)
377 {
378 
379 	return (pci_enable_busmaster(dev));
380 }
381 
382 static int
383 vga_pci_disable_busmaster(device_t dev, device_t child)
384 {
385 
386 	return (pci_disable_busmaster(dev));
387 }
388 
389 static int
390 vga_pci_enable_io(device_t dev, device_t child, int space)
391 {
392 
393 	device_printf(dev, "child %s requested pci_enable_io\n",
394 	    device_get_nameunit(child));
395 	return (pci_enable_io(dev, space));
396 }
397 
398 static int
399 vga_pci_disable_io(device_t dev, device_t child, int space)
400 {
401 
402 	device_printf(dev, "child %s requested pci_disable_io\n",
403 	    device_get_nameunit(child));
404 	return (pci_disable_io(dev, space));
405 }
406 
407 static int
408 vga_pci_get_vpd_ident(device_t dev, device_t child, const char **identptr)
409 {
410 
411 	return (pci_get_vpd_ident(dev, identptr));
412 }
413 
414 static int
415 vga_pci_get_vpd_readonly(device_t dev, device_t child, const char *kw,
416     const char **vptr)
417 {
418 
419 	return (pci_get_vpd_readonly(dev, kw, vptr));
420 }
421 
422 static int
423 vga_pci_set_powerstate(device_t dev, device_t child, int state)
424 {
425 
426 	device_printf(dev, "child %s requested pci_set_powerstate\n",
427 	    device_get_nameunit(child));
428 	return (pci_set_powerstate(dev, state));
429 }
430 
431 static int
432 vga_pci_get_powerstate(device_t dev, device_t child)
433 {
434 
435 	device_printf(dev, "child %s requested pci_get_powerstate\n",
436 	    device_get_nameunit(child));
437 	return (pci_get_powerstate(dev));
438 }
439 
440 static int
441 vga_pci_assign_interrupt(device_t dev, device_t child)
442 {
443 
444 	device_printf(dev, "child %s requested pci_assign_interrupt\n",
445 	    device_get_nameunit(child));
446 	return (PCI_ASSIGN_INTERRUPT(device_get_parent(dev), dev));
447 }
448 
449 static int
450 vga_pci_find_cap(device_t dev, device_t child, int capability,
451     int *capreg)
452 {
453 
454 	return (pci_find_cap(dev, capability, capreg));
455 }
456 
457 static int
458 vga_pci_find_extcap(device_t dev, device_t child, int capability,
459     int *capreg)
460 {
461 
462 	return (pci_find_extcap(dev, capability, capreg));
463 }
464 
465 static int
466 vga_pci_find_htcap(device_t dev, device_t child, int capability,
467     int *capreg)
468 {
469 
470 	return (pci_find_htcap(dev, capability, capreg));
471 }
472 
473 static int
474 vga_pci_alloc_msi(device_t dev, device_t child, int *count)
475 {
476 	struct vga_pci_softc *sc;
477 	int error;
478 
479 	sc = device_get_softc(dev);
480 	if (sc->vga_msi_child != NULL)
481 		return (EBUSY);
482 	error = pci_alloc_msi(dev, count);
483 	if (error == 0)
484 		sc->vga_msi_child = child;
485 	return (error);
486 }
487 
488 static int
489 vga_pci_alloc_msix(device_t dev, device_t child, int *count)
490 {
491 	struct vga_pci_softc *sc;
492 	int error;
493 
494 	sc = device_get_softc(dev);
495 	if (sc->vga_msi_child != NULL)
496 		return (EBUSY);
497 	error = pci_alloc_msix(dev, count);
498 	if (error == 0)
499 		sc->vga_msi_child = child;
500 	return (error);
501 }
502 
503 static int
504 vga_pci_remap_msix(device_t dev, device_t child, int count,
505     const u_int *vectors)
506 {
507 	struct vga_pci_softc *sc;
508 
509 	sc = device_get_softc(dev);
510 	if (sc->vga_msi_child != child)
511 		return (ENXIO);
512 	return (pci_remap_msix(dev, count, vectors));
513 }
514 
515 static int
516 vga_pci_release_msi(device_t dev, device_t child)
517 {
518 	struct vga_pci_softc *sc;
519 	int error;
520 
521 	sc = device_get_softc(dev);
522 	if (sc->vga_msi_child != child)
523 		return (ENXIO);
524 	error = pci_release_msi(dev);
525 	if (error == 0)
526 		sc->vga_msi_child = NULL;
527 	return (error);
528 }
529 
530 static int
531 vga_pci_msi_count(device_t dev, device_t child)
532 {
533 
534 	return (pci_msi_count(dev));
535 }
536 
537 static int
538 vga_pci_msix_count(device_t dev, device_t child)
539 {
540 
541 	return (pci_msix_count(dev));
542 }
543 
544 static bus_dma_tag_t
545 vga_pci_get_dma_tag(device_t bus, device_t child)
546 {
547 
548 	return (bus_get_dma_tag(bus));
549 }
550 
551 static device_method_t vga_pci_methods[] = {
552 	/* Device interface */
553 	DEVMETHOD(device_probe,		vga_pci_probe),
554 	DEVMETHOD(device_attach,	vga_pci_attach),
555 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
556 	DEVMETHOD(device_suspend,	vga_pci_suspend),
557 	DEVMETHOD(device_resume,	vga_pci_resume),
558 
559 	/* Bus interface */
560 	DEVMETHOD(bus_read_ivar,	vga_pci_read_ivar),
561 	DEVMETHOD(bus_write_ivar,	vga_pci_write_ivar),
562 	DEVMETHOD(bus_setup_intr,	vga_pci_setup_intr),
563 	DEVMETHOD(bus_teardown_intr,	vga_pci_teardown_intr),
564 	DEVMETHOD(bus_alloc_resource,	vga_pci_alloc_resource),
565 	DEVMETHOD(bus_release_resource,	vga_pci_release_resource),
566 	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
567 	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
568 	DEVMETHOD(bus_get_dma_tag,	vga_pci_get_dma_tag),
569 
570 	/* PCI interface */
571 	DEVMETHOD(pci_read_config,	vga_pci_read_config),
572 	DEVMETHOD(pci_write_config,	vga_pci_write_config),
573 	DEVMETHOD(pci_enable_busmaster,	vga_pci_enable_busmaster),
574 	DEVMETHOD(pci_disable_busmaster, vga_pci_disable_busmaster),
575 	DEVMETHOD(pci_enable_io,	vga_pci_enable_io),
576 	DEVMETHOD(pci_disable_io,	vga_pci_disable_io),
577 	DEVMETHOD(pci_get_vpd_ident,	vga_pci_get_vpd_ident),
578 	DEVMETHOD(pci_get_vpd_readonly,	vga_pci_get_vpd_readonly),
579 	DEVMETHOD(pci_get_powerstate,	vga_pci_get_powerstate),
580 	DEVMETHOD(pci_set_powerstate,	vga_pci_set_powerstate),
581 	DEVMETHOD(pci_assign_interrupt,	vga_pci_assign_interrupt),
582 	DEVMETHOD(pci_find_cap,		vga_pci_find_cap),
583 	DEVMETHOD(pci_find_extcap,	vga_pci_find_extcap),
584 	DEVMETHOD(pci_find_htcap,	vga_pci_find_htcap),
585 	DEVMETHOD(pci_alloc_msi,	vga_pci_alloc_msi),
586 	DEVMETHOD(pci_alloc_msix,	vga_pci_alloc_msix),
587 	DEVMETHOD(pci_remap_msix,	vga_pci_remap_msix),
588 	DEVMETHOD(pci_release_msi,	vga_pci_release_msi),
589 	DEVMETHOD(pci_msi_count,	vga_pci_msi_count),
590 	DEVMETHOD(pci_msix_count,	vga_pci_msix_count),
591 
592 	{ 0, 0 }
593 };
594 
595 static driver_t vga_pci_driver = {
596 	"vgapci",
597 	vga_pci_methods,
598 	sizeof(struct vga_pci_softc),
599 };
600 
601 static devclass_t vga_devclass;
602 
603 DRIVER_MODULE(vgapci, pci, vga_pci_driver, vga_devclass, 0, 0);
604