vga_pci.c revision 331111
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: stable/11/sys/dev/pci/vga_pci.c 331111 2018-03-17 20:20:29Z bryanv $");
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
58struct vga_resource {
59	struct resource	*vr_res;
60	int	vr_refs;
61};
62
63struct 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
69SYSCTL_DECL(_hw_pci);
70
71static struct vga_resource *lookup_res(struct vga_pci_softc *sc, int rid);
72static 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);
75static int	vga_pci_release_resource(device_t dev, device_t child, int type,
76    int rid, struct resource *r);
77
78int vga_pci_default_unit = -1;
79SYSCTL_INT(_hw_pci, OID_AUTO, default_vgapci_unit, CTLFLAG_RDTUN,
80    &vga_pci_default_unit, -1, "Default VGA-compatible display");
81
82int
83vga_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
146void *
147vga_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
179void
180vga_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
209int
210vga_pci_repost(device_t dev)
211{
212#if defined(__amd64__) || (defined(__i386__) && !defined(PC98))
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
239static int
240vga_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
261static int
262vga_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
278static int
279vga_pci_suspend(device_t dev)
280{
281
282	return (bus_generic_suspend(dev));
283}
284
285static int
286vga_pci_resume(device_t dev)
287{
288
289	return (bus_generic_resume(dev));
290}
291
292/* Bus interface. */
293
294static int
295vga_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
301static int
302vga_pci_write_ivar(device_t dev, device_t child, int which, uintptr_t value)
303{
304
305	return (EINVAL);
306}
307
308static int
309vga_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
317static int
318vga_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
324static struct vga_resource *
325lookup_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
337static struct resource *
338vga_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
363static int
364vga_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
402static uint32_t
403vga_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
409static void
410vga_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
417static int
418vga_pci_enable_busmaster(device_t dev, device_t child)
419{
420
421	return (pci_enable_busmaster(dev));
422}
423
424static int
425vga_pci_disable_busmaster(device_t dev, device_t child)
426{
427
428	return (pci_disable_busmaster(dev));
429}
430
431static int
432vga_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
440static int
441vga_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
449static int
450vga_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
456static int
457vga_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
464static int
465vga_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
473static int
474vga_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
482static int
483vga_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
491static int
492vga_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
499static int
500vga_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
507static int
508vga_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
515static int
516vga_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
523static int
524vga_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
531static int
532vga_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
539static int
540vga_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
554static int
555vga_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
569static int
570vga_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
581static int
582vga_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
596static int
597vga_pci_msi_count(device_t dev, device_t child)
598{
599
600	return (pci_msi_count(dev));
601}
602
603static int
604vga_pci_msix_count(device_t dev, device_t child)
605{
606
607	return (pci_msix_count(dev));
608}
609
610static bus_dma_tag_t
611vga_pci_get_dma_tag(device_t bus, device_t child)
612{
613
614	return (bus_get_dma_tag(bus));
615}
616
617static 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
664static driver_t vga_pci_driver = {
665	"vgapci",
666	vga_pci_methods,
667	sizeof(struct vga_pci_softc),
668};
669
670static devclass_t vga_devclass;
671
672DRIVER_MODULE(vgapci, pci, vga_pci_driver, vga_devclass, 0, 0);
673MODULE_DEPEND(vgapci, x86bios, 1, 1, 1);
674