xref: /freebsd/sys/dev/pci/vga_pci.c (revision 6d732c66bca5da4d261577aad2c8ea84519b0bea)
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  * 3. Neither the name of the author nor the names of any co-contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 /*
34  * Simple driver for PCI VGA display devices.  Drivers such as agp(4) and
35  * drm(4) should attach as children of this device.
36  *
37  * XXX: The vgapci name is a hack until we somehow merge the isa vga driver
38  * in or rename it.
39  */
40 
41 #include <sys/param.h>
42 #include <sys/bus.h>
43 #include <sys/kernel.h>
44 #include <sys/module.h>
45 #include <sys/rman.h>
46 #include <sys/sysctl.h>
47 #include <sys/systm.h>
48 
49 #if defined(__amd64__) || defined(__i386__) || defined(__ia64__)
50 #include <vm/vm.h>
51 #include <vm/pmap.h>
52 #endif
53 
54 #include <dev/pci/pcireg.h>
55 #include <dev/pci/pcivar.h>
56 
57 struct vga_resource {
58 	struct resource	*vr_res;
59 	int	vr_refs;
60 };
61 
62 struct vga_pci_softc {
63 	device_t	vga_msi_child;	/* Child driver using MSI. */
64 	struct vga_resource vga_bars[PCIR_MAX_BAR_0 + 1];
65 	struct vga_resource vga_bios;
66 };
67 
68 SYSCTL_DECL(_hw_pci);
69 
70 static struct vga_resource *lookup_res(struct vga_pci_softc *sc, int rid);
71 static struct resource *vga_pci_alloc_resource(device_t dev, device_t child,
72     int type, int *rid, u_long start, u_long end, u_long count, u_int flags);
73 static int	vga_pci_release_resource(device_t dev, device_t child, int type,
74     int rid, struct resource *r);
75 
76 int vga_pci_default_unit = -1;
77 TUNABLE_INT("hw.pci.default_vgapci_unit", &vga_pci_default_unit);
78 SYSCTL_INT(_hw_pci, OID_AUTO, default_vgapci_unit, CTLFLAG_RDTUN,
79     &vga_pci_default_unit, -1, "Default VGA-compatible display");
80 
81 int
82 vga_pci_is_boot_display(device_t dev)
83 {
84 	int unit;
85 	device_t pcib;
86 	uint16_t config;
87 
88 	/* Check that the given device is a video card */
89 	if ((pci_get_class(dev) != PCIC_DISPLAY &&
90 	    (pci_get_class(dev) != PCIC_OLD ||
91 	     pci_get_subclass(dev) != PCIS_OLD_VGA)))
92 		return (0);
93 
94 	unit = device_get_unit(dev);
95 
96 	if (vga_pci_default_unit >= 0) {
97 		/*
98 		 * The boot display device was determined by a previous
99 		 * call to this function, or the user forced it using
100 		 * the hw.pci.default_vgapci_unit tunable.
101 		 */
102 		return (vga_pci_default_unit == unit);
103 	}
104 
105 	/*
106 	 * The primary video card used as a boot display must have the
107 	 * "I/O" and "Memory Address Space Decoding" bits set in its
108 	 * Command register.
109 	 *
110 	 * Furthermore, if the card is attached to a bridge, instead of
111 	 * the root PCI bus, the bridge must have the "VGA Enable" bit
112 	 * set in its Control register.
113 	 */
114 
115 	pcib = device_get_parent(device_get_parent(dev));
116 	if (device_get_devclass(device_get_parent(pcib)) ==
117 	    devclass_find("pci")) {
118 		/*
119 		 * The parent bridge is a PCI-to-PCI bridge: check the
120 		 * value of the "VGA Enable" bit.
121 		 */
122 		config = pci_read_config(pcib, PCIR_BRIDGECTL_1, 2);
123 		if ((config & PCIB_BCR_VGA_ENABLE) == 0)
124 			return (0);
125 	}
126 
127 	config = pci_read_config(dev, PCIR_COMMAND, 2);
128 	if ((config & (PCIM_CMD_PORTEN | PCIM_CMD_MEMEN)) == 0)
129 		return (0);
130 
131 	/* This video card is the boot display: record its unit number. */
132 	vga_pci_default_unit = unit;
133 	device_set_flags(dev, 1);
134 
135 	return (1);
136 }
137 
138 void *
139 vga_pci_map_bios(device_t dev, size_t *size)
140 {
141 	int rid;
142 	struct resource *res;
143 
144 #if defined(__amd64__) || defined(__i386__) || defined(__ia64__)
145 	if (vga_pci_is_boot_display(dev)) {
146 		/*
147 		 * On x86, the System BIOS copy the default display
148 		 * device's Video BIOS at a fixed location in system
149 		 * memory (0xC0000, 128 kBytes long) at boot time.
150 		 *
151 		 * We use this copy for the default boot device, because
152 		 * the original ROM may not be valid after boot.
153 		 */
154 
155 		*size = VGA_PCI_BIOS_SHADOW_SIZE;
156 		return (pmap_mapbios(VGA_PCI_BIOS_SHADOW_ADDR, *size));
157 	}
158 #endif
159 
160 	rid = PCIR_BIOS;
161 	res = vga_pci_alloc_resource(dev, NULL, SYS_RES_MEMORY, &rid, 0ul,
162 	    ~0ul, 1, RF_ACTIVE);
163 	if (res == NULL) {
164 		return (NULL);
165 	}
166 
167 	*size = rman_get_size(res);
168 	return (rman_get_virtual(res));
169 }
170 
171 void
172 vga_pci_unmap_bios(device_t dev, void *bios)
173 {
174 	struct vga_resource *vr;
175 
176 	if (bios == NULL) {
177 		return;
178 	}
179 
180 #if defined(__amd64__) || defined(__i386__) || defined(__ia64__)
181 	if (vga_pci_is_boot_display(dev)) {
182 		/* We mapped the BIOS shadow copy located at 0xC0000. */
183 		pmap_unmapdev((vm_offset_t)bios, VGA_PCI_BIOS_SHADOW_SIZE);
184 
185 		return;
186 	}
187 #endif
188 
189 	/*
190 	 * Look up the PCIR_BIOS resource in our softc.  It should match
191 	 * the address we returned previously.
192 	 */
193 	vr = lookup_res(device_get_softc(dev), PCIR_BIOS);
194 	KASSERT(vr->vr_res != NULL, ("vga_pci_unmap_bios: bios not mapped"));
195 	KASSERT(rman_get_virtual(vr->vr_res) == bios,
196 	    ("vga_pci_unmap_bios: mismatch"));
197 	vga_pci_release_resource(dev, NULL, SYS_RES_MEMORY, PCIR_BIOS,
198 	    vr->vr_res);
199 }
200 
201 static int
202 vga_pci_probe(device_t dev)
203 {
204 
205 	switch (pci_get_class(dev)) {
206 	case PCIC_DISPLAY:
207 		break;
208 	case PCIC_OLD:
209 		if (pci_get_subclass(dev) != PCIS_OLD_VGA)
210 			return (ENXIO);
211 		break;
212 	default:
213 		return (ENXIO);
214 	}
215 
216 	/* Probe default display. */
217 	vga_pci_is_boot_display(dev);
218 
219 	device_set_desc(dev, "VGA-compatible display");
220 	return (BUS_PROBE_GENERIC);
221 }
222 
223 static int
224 vga_pci_attach(device_t dev)
225 {
226 
227 	bus_generic_probe(dev);
228 
229 	/* Always create a drm child for now to make it easier on drm. */
230 	device_add_child(dev, "drm", -1);
231 	device_add_child(dev, "drmn", -1);
232 	bus_generic_attach(dev);
233 
234 	if (vga_pci_is_boot_display(dev))
235 		device_printf(dev, "Boot video device\n");
236 
237 	return (0);
238 }
239 
240 static int
241 vga_pci_suspend(device_t dev)
242 {
243 
244 	return (bus_generic_suspend(dev));
245 }
246 
247 static int
248 vga_pci_resume(device_t dev)
249 {
250 
251 	return (bus_generic_resume(dev));
252 }
253 
254 /* Bus interface. */
255 
256 static int
257 vga_pci_read_ivar(device_t dev, device_t child, int which, uintptr_t *result)
258 {
259 
260 	return (BUS_READ_IVAR(device_get_parent(dev), dev, which, result));
261 }
262 
263 static int
264 vga_pci_write_ivar(device_t dev, device_t child, int which, uintptr_t value)
265 {
266 
267 	return (EINVAL);
268 }
269 
270 static int
271 vga_pci_setup_intr(device_t dev, device_t child, struct resource *irq,
272     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
273     void **cookiep)
274 {
275 	return (BUS_SETUP_INTR(device_get_parent(dev), dev, irq, flags,
276 	    filter, intr, arg, cookiep));
277 }
278 
279 static int
280 vga_pci_teardown_intr(device_t dev, device_t child, struct resource *irq,
281     void *cookie)
282 {
283 	return (BUS_TEARDOWN_INTR(device_get_parent(dev), dev, irq, cookie));
284 }
285 
286 static struct vga_resource *
287 lookup_res(struct vga_pci_softc *sc, int rid)
288 {
289 	int bar;
290 
291 	if (rid == PCIR_BIOS)
292 		return (&sc->vga_bios);
293 	bar = PCI_RID2BAR(rid);
294 	if (bar >= 0 && bar <= PCIR_MAX_BAR_0)
295 		return (&sc->vga_bars[bar]);
296 	return (NULL);
297 }
298 
299 static struct resource *
300 vga_pci_alloc_resource(device_t dev, device_t child, int type, int *rid,
301     u_long start, u_long end, u_long count, u_int flags)
302 {
303 	struct vga_resource *vr;
304 
305 	switch (type) {
306 	case SYS_RES_MEMORY:
307 	case SYS_RES_IOPORT:
308 		/*
309 		 * For BARs, we cache the resource so that we only allocate it
310 		 * from the PCI bus once.
311 		 */
312 		vr = lookup_res(device_get_softc(dev), *rid);
313 		if (vr == NULL)
314 			return (NULL);
315 		if (vr->vr_res == NULL)
316 			vr->vr_res = bus_alloc_resource(dev, type, rid, start,
317 			    end, count, flags);
318 		if (vr->vr_res != NULL)
319 			vr->vr_refs++;
320 		return (vr->vr_res);
321 	}
322 	return (bus_alloc_resource(dev, type, rid, start, end, count, flags));
323 }
324 
325 static int
326 vga_pci_release_resource(device_t dev, device_t child, int type, int rid,
327     struct resource *r)
328 {
329 	struct vga_resource *vr;
330 	int error;
331 
332 	switch (type) {
333 	case SYS_RES_MEMORY:
334 	case SYS_RES_IOPORT:
335 		/*
336 		 * For BARs, we release the resource from the PCI bus
337 		 * when the last child reference goes away.
338 		 */
339 		vr = lookup_res(device_get_softc(dev), rid);
340 		if (vr == NULL)
341 			return (EINVAL);
342 		if (vr->vr_res == NULL)
343 			return (EINVAL);
344 		KASSERT(vr->vr_res == r, ("vga_pci resource mismatch"));
345 		if (vr->vr_refs > 1) {
346 			vr->vr_refs--;
347 			return (0);
348 		}
349 		KASSERT(vr->vr_refs > 0,
350 		    ("vga_pci resource reference count underflow"));
351 		error = bus_release_resource(dev, type, rid, r);
352 		if (error == 0) {
353 			vr->vr_res = NULL;
354 			vr->vr_refs = 0;
355 		}
356 		return (error);
357 	}
358 
359 	return (bus_release_resource(dev, type, rid, r));
360 }
361 
362 /* PCI interface. */
363 
364 static uint32_t
365 vga_pci_read_config(device_t dev, device_t child, int reg, int width)
366 {
367 
368 	return (pci_read_config(dev, reg, width));
369 }
370 
371 static void
372 vga_pci_write_config(device_t dev, device_t child, int reg,
373     uint32_t val, int width)
374 {
375 
376 	pci_write_config(dev, reg, val, width);
377 }
378 
379 static int
380 vga_pci_enable_busmaster(device_t dev, device_t child)
381 {
382 
383 	return (pci_enable_busmaster(dev));
384 }
385 
386 static int
387 vga_pci_disable_busmaster(device_t dev, device_t child)
388 {
389 
390 	return (pci_disable_busmaster(dev));
391 }
392 
393 static int
394 vga_pci_enable_io(device_t dev, device_t child, int space)
395 {
396 
397 	device_printf(dev, "child %s requested pci_enable_io\n",
398 	    device_get_nameunit(child));
399 	return (pci_enable_io(dev, space));
400 }
401 
402 static int
403 vga_pci_disable_io(device_t dev, device_t child, int space)
404 {
405 
406 	device_printf(dev, "child %s requested pci_disable_io\n",
407 	    device_get_nameunit(child));
408 	return (pci_disable_io(dev, space));
409 }
410 
411 static int
412 vga_pci_get_vpd_ident(device_t dev, device_t child, const char **identptr)
413 {
414 
415 	return (pci_get_vpd_ident(dev, identptr));
416 }
417 
418 static int
419 vga_pci_get_vpd_readonly(device_t dev, device_t child, const char *kw,
420     const char **vptr)
421 {
422 
423 	return (pci_get_vpd_readonly(dev, kw, vptr));
424 }
425 
426 static int
427 vga_pci_set_powerstate(device_t dev, device_t child, int state)
428 {
429 
430 	device_printf(dev, "child %s requested pci_set_powerstate\n",
431 	    device_get_nameunit(child));
432 	return (pci_set_powerstate(dev, state));
433 }
434 
435 static int
436 vga_pci_get_powerstate(device_t dev, device_t child)
437 {
438 
439 	device_printf(dev, "child %s requested pci_get_powerstate\n",
440 	    device_get_nameunit(child));
441 	return (pci_get_powerstate(dev));
442 }
443 
444 static int
445 vga_pci_assign_interrupt(device_t dev, device_t child)
446 {
447 
448 	device_printf(dev, "child %s requested pci_assign_interrupt\n",
449 	    device_get_nameunit(child));
450 	return (PCI_ASSIGN_INTERRUPT(device_get_parent(dev), dev));
451 }
452 
453 static int
454 vga_pci_find_cap(device_t dev, device_t child, int capability,
455     int *capreg)
456 {
457 
458 	return (pci_find_cap(dev, capability, capreg));
459 }
460 
461 static int
462 vga_pci_find_extcap(device_t dev, device_t child, int capability,
463     int *capreg)
464 {
465 
466 	return (pci_find_extcap(dev, capability, capreg));
467 }
468 
469 static int
470 vga_pci_find_htcap(device_t dev, device_t child, int capability,
471     int *capreg)
472 {
473 
474 	return (pci_find_htcap(dev, capability, capreg));
475 }
476 
477 static int
478 vga_pci_alloc_msi(device_t dev, device_t child, int *count)
479 {
480 	struct vga_pci_softc *sc;
481 	int error;
482 
483 	sc = device_get_softc(dev);
484 	if (sc->vga_msi_child != NULL)
485 		return (EBUSY);
486 	error = pci_alloc_msi(dev, count);
487 	if (error == 0)
488 		sc->vga_msi_child = child;
489 	return (error);
490 }
491 
492 static int
493 vga_pci_alloc_msix(device_t dev, device_t child, int *count)
494 {
495 	struct vga_pci_softc *sc;
496 	int error;
497 
498 	sc = device_get_softc(dev);
499 	if (sc->vga_msi_child != NULL)
500 		return (EBUSY);
501 	error = pci_alloc_msix(dev, count);
502 	if (error == 0)
503 		sc->vga_msi_child = child;
504 	return (error);
505 }
506 
507 static int
508 vga_pci_remap_msix(device_t dev, device_t child, int count,
509     const u_int *vectors)
510 {
511 	struct vga_pci_softc *sc;
512 
513 	sc = device_get_softc(dev);
514 	if (sc->vga_msi_child != child)
515 		return (ENXIO);
516 	return (pci_remap_msix(dev, count, vectors));
517 }
518 
519 static int
520 vga_pci_release_msi(device_t dev, device_t child)
521 {
522 	struct vga_pci_softc *sc;
523 	int error;
524 
525 	sc = device_get_softc(dev);
526 	if (sc->vga_msi_child != child)
527 		return (ENXIO);
528 	error = pci_release_msi(dev);
529 	if (error == 0)
530 		sc->vga_msi_child = NULL;
531 	return (error);
532 }
533 
534 static int
535 vga_pci_msi_count(device_t dev, device_t child)
536 {
537 
538 	return (pci_msi_count(dev));
539 }
540 
541 static int
542 vga_pci_msix_count(device_t dev, device_t child)
543 {
544 
545 	return (pci_msix_count(dev));
546 }
547 
548 static bus_dma_tag_t
549 vga_pci_get_dma_tag(device_t bus, device_t child)
550 {
551 
552 	return (bus_get_dma_tag(bus));
553 }
554 
555 static device_method_t vga_pci_methods[] = {
556 	/* Device interface */
557 	DEVMETHOD(device_probe,		vga_pci_probe),
558 	DEVMETHOD(device_attach,	vga_pci_attach),
559 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
560 	DEVMETHOD(device_suspend,	vga_pci_suspend),
561 	DEVMETHOD(device_resume,	vga_pci_resume),
562 
563 	/* Bus interface */
564 	DEVMETHOD(bus_read_ivar,	vga_pci_read_ivar),
565 	DEVMETHOD(bus_write_ivar,	vga_pci_write_ivar),
566 	DEVMETHOD(bus_setup_intr,	vga_pci_setup_intr),
567 	DEVMETHOD(bus_teardown_intr,	vga_pci_teardown_intr),
568 	DEVMETHOD(bus_alloc_resource,	vga_pci_alloc_resource),
569 	DEVMETHOD(bus_release_resource,	vga_pci_release_resource),
570 	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
571 	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
572 	DEVMETHOD(bus_get_dma_tag,	vga_pci_get_dma_tag),
573 
574 	/* PCI interface */
575 	DEVMETHOD(pci_read_config,	vga_pci_read_config),
576 	DEVMETHOD(pci_write_config,	vga_pci_write_config),
577 	DEVMETHOD(pci_enable_busmaster,	vga_pci_enable_busmaster),
578 	DEVMETHOD(pci_disable_busmaster, vga_pci_disable_busmaster),
579 	DEVMETHOD(pci_enable_io,	vga_pci_enable_io),
580 	DEVMETHOD(pci_disable_io,	vga_pci_disable_io),
581 	DEVMETHOD(pci_get_vpd_ident,	vga_pci_get_vpd_ident),
582 	DEVMETHOD(pci_get_vpd_readonly,	vga_pci_get_vpd_readonly),
583 	DEVMETHOD(pci_get_powerstate,	vga_pci_get_powerstate),
584 	DEVMETHOD(pci_set_powerstate,	vga_pci_set_powerstate),
585 	DEVMETHOD(pci_assign_interrupt,	vga_pci_assign_interrupt),
586 	DEVMETHOD(pci_find_cap,		vga_pci_find_cap),
587 	DEVMETHOD(pci_find_extcap,	vga_pci_find_extcap),
588 	DEVMETHOD(pci_find_htcap,	vga_pci_find_htcap),
589 	DEVMETHOD(pci_alloc_msi,	vga_pci_alloc_msi),
590 	DEVMETHOD(pci_alloc_msix,	vga_pci_alloc_msix),
591 	DEVMETHOD(pci_remap_msix,	vga_pci_remap_msix),
592 	DEVMETHOD(pci_release_msi,	vga_pci_release_msi),
593 	DEVMETHOD(pci_msi_count,	vga_pci_msi_count),
594 	DEVMETHOD(pci_msix_count,	vga_pci_msix_count),
595 
596 	{ 0, 0 }
597 };
598 
599 static driver_t vga_pci_driver = {
600 	"vgapci",
601 	vga_pci_methods,
602 	sizeof(struct vga_pci_softc),
603 };
604 
605 static devclass_t vga_devclass;
606 
607 DRIVER_MODULE(vgapci, pci, vga_pci_driver, vga_devclass, 0, 0);
608