path: root/usr.sbin/pcidump/pcidump.c

/*	$OpenBSD: pcidump.c,v 1.22 2010/03/01 19:00:47 kettenis Exp $	*/

/*
 * Copyright (c) 2006, 2007 David Gwynne <loki@animata.net>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/ioctl.h>
#include <sys/param.h>
#include <sys/pciio.h>

#include <dev/pci/pcireg.h>
#include <dev/pci/pcidevs.h>
#include <dev/pci/pcidevs_data.h>

#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#define PCIDEV	"/dev/pci"

__dead void usage(void);
void scanpcidomain(void);
int probe(int, int, int);
void dump(int, int, int);
void hexdump(int, int, int, int);
const char *str2busdevfunc(const char *, int *, int *, int *);
int pci_nfuncs(int, int);
int pci_read(int, int, int, u_int32_t, u_int32_t *);
void dump_caplist(int, int, int, u_int8_t);
int dump_rom(int, int, int);
int dump_vga_bios(void);

__dead void
usage(void)
{
	extern char *__progname;

	fprintf(stderr,
	    "usage: %s [-v] [-x | -xx] [-d pcidev] [bus:dev:func]\n"
	    "       %s -r file [-d pcidev] bus:dev:func\n",
	    __progname, __progname);
	exit(1);
}

int pcifd;
int romfd;
int verbose = 0;
int hex = 0;

const char *pci_capnames[] = {
	"Reserved",
	"Power Management",
	"AGP",
	"Vital Product Data (VPD)",
	"Slot Identification",
	"Message Signaled Interrupts (MSI)",
	"CompactPCI Hot Swap",
	"PCI-X",
	"AMD LDT/HT",
	"Vendor Specific",
	"Debug Port",
	"CompactPCI Central Resource Control",
	"PCI Hot-Plug",
	"PCI-PCI",
	"AGP8",
	"Secure",
	"PCI Express",
	"Extended Message Signaled Interrupts (MSI-X)"
};
#define PCI_CAPNAMES_MAX	PCI_CAP_MSIX

int
main(int argc, char *argv[])
{
	int nfuncs;
	int bus, dev, func;
	char pcidev[MAXPATHLEN] = PCIDEV;
	char *romfile = NULL;
	const char *errstr;
	int c, error = 0, dumpall = 1, domid = 0;

	while ((c = getopt(argc, argv, "d:r:vx")) != -1) {
		switch (c) {
		case 'd':
			strlcpy(pcidev, optarg, sizeof(pcidev));
			dumpall = 0;
			break;
		case 'r':
			romfile = optarg;
			dumpall = 0;
			break;
		case 'v':
			verbose = 1;
			break;
		case 'x':
			hex++;
			break;
		default:
			usage();
		}
	}
	argc -= optind;
	argv += optind;

	if (argc > 1 || (romfile && argc != 1))
		usage();

	if (romfile) {
		romfd = open(romfile, O_WRONLY|O_CREAT|O_TRUNC, 0777);
		if (romfd == -1)
			err(1, "%s", romfile);
	}

	if (argc == 1)
		dumpall = 0;

	if (dumpall == 0) {
		pcifd = open(pcidev, O_RDONLY, 0777);
		if (pcifd == -1)
			err(1, "%s", pcidev);
	} else {
		for (;;) {
			snprintf(pcidev, 16, "/dev/pci%d", domid++);
			pcifd = open(pcidev, O_RDONLY, 0777);
			if (pcifd == -1) {
				if (errno == ENXIO || errno == ENOENT) {
					return 0;
				} else {
					err(1, "%s", pcidev);
				}
			}
			printf("Domain %s:\n", pcidev);
			scanpcidomain();
			close(pcifd);
		}
	}

	if (argc == 1) {
		errstr = str2busdevfunc(argv[0], &bus, &dev, &func);
		if (errstr != NULL)
			errx(1, "\"%s\": %s", argv[0], errstr);

		nfuncs = pci_nfuncs(bus, dev);
		if (nfuncs == -1 || func > nfuncs)
			error = ENXIO;
		else if (romfile)
			error = dump_rom(bus, dev, func);
		else
			error = probe(bus, dev, func);

		if (error != 0)
			errx(1, "\"%s\": %s", argv[0], strerror(error));
	} else {
		printf("Domain %s:\n", pcidev);
		scanpcidomain();
	}

	return (0);
}

void
scanpcidomain(void)
{
	int nfuncs;
	int bus, dev, func;

	for (bus = 0; bus < 256; bus++) {
		for (dev = 0; dev < 32; dev++) {
			nfuncs = pci_nfuncs(bus, dev);
			for (func = 0; func < nfuncs; func++) {
				probe(bus, dev, func);
			}
		}
	}
}

const char *
str2busdevfunc(const char *string, int *bus, int *dev, int *func)
{
	const char *errstr;
	char b[80], *d, *f;

	strlcpy(b, string, sizeof(b));

	d = strchr(b, ':');
	if (d == NULL)
		return("device not specified");
	*d++ = '\0';

	f = strchr(d, ':');
	if (f == NULL)
		return("function not specified");
	*f++ = '\0';

	*bus = strtonum(b, 0, 255, &errstr);
	if (errstr != NULL)
		return (errstr);
	*dev = strtonum(d, 0, 31, &errstr);
	if (errstr != NULL)
		return (errstr);
	*func = strtonum(f, 0, 7, &errstr);
	if (errstr != NULL)
		return (errstr);

	return (NULL);
}

int
probe(int bus, int dev, int func)
{
	u_int32_t id_reg;
	const struct pci_known_vendor *pkv;
	const struct pci_known_product *pkp;
	const char *vendor = NULL, *product = NULL;

	if (pci_read(bus, dev, func, PCI_ID_REG, &id_reg) != 0)
		return (errno);

	if (PCI_VENDOR(id_reg) == PCI_VENDOR_INVALID ||
	    PCI_VENDOR(id_reg) == 0)
		return (ENXIO);

	for (pkv = pci_known_vendors; pkv->vendorname != NULL; pkv++) {
		if (pkv->vendor == PCI_VENDOR(id_reg)) {
			vendor = pkv->vendorname;
			break;
		}
	}

	if (vendor != NULL) {
		for (pkp = pci_known_products; pkp->productname != NULL; pkp++)
		if (pkp->vendor == PCI_VENDOR(id_reg) &&
		    pkp->product == PCI_PRODUCT(id_reg)) {
			product = pkp->productname;
			break;
		}
	}

	printf(" %d:%d:%d: %s %s\n", bus, dev, func,
	    (vendor == NULL) ? "unknown" : vendor,
	    (product == NULL) ? "unknown" : product);

	if (verbose)
		dump(bus, dev, func);
	if (hex > 0)
		hexdump(bus, dev, func, hex > 1);

	return (0);
}

void
dump_caplist(int bus, int dev, int func, u_int8_t ptr)
{
	u_int32_t reg;
	u_int8_t cap;

	if (pci_read(bus, dev, func, PCI_COMMAND_STATUS_REG, &reg) != 0)
		return;
	if (!(reg & PCI_STATUS_CAPLIST_SUPPORT))
		return;

	if (pci_read(bus, dev, func, ptr, &reg) != 0)
		return;
	ptr = PCI_CAPLIST_PTR(reg);
	while (ptr != 0) {
		if (pci_read(bus, dev, func, ptr, &reg) != 0)
			return;
		cap = PCI_CAPLIST_CAP(reg);
		printf("\t0x%04x: Capability 0x%02x: ", ptr, cap);
		if (cap > PCI_CAPNAMES_MAX)
			cap = 0;
		printf("%s\n", pci_capnames[cap]);
		ptr = PCI_CAPLIST_NEXT(reg);
	}
}

void
dump_type0(int bus, int dev, int func)
{
	const char *memtype;
	u_int64_t mem;
	u_int32_t reg;
	int bar;

	for (bar = PCI_MAPREG_START; bar < PCI_MAPREG_END; bar += 0x4) {
		if (pci_read(bus, dev, func, bar, &reg) != 0)
			warn("unable to read PCI_MAPREG 0x%02x", bar);

		printf("\t0x%04x: BAR ", bar);

		if (reg == 0x0) {
			printf("empty (%08x)\n", reg);
			continue;
		}

		switch (PCI_MAPREG_TYPE(reg)) {
		case PCI_MAPREG_TYPE_MEM:
			printf("mem ");
			if (PCI_MAPREG_MEM_PREFETCHABLE(reg))
				printf("prefetchable ");

			memtype = "32bit 1m";
			switch (PCI_MAPREG_MEM_TYPE(reg)) {
			case PCI_MAPREG_MEM_TYPE_32BIT:
				memtype = "32bit";
			case PCI_MAPREG_MEM_TYPE_32BIT_1M:
				printf("%s ", memtype);

				printf("addr: 0x%08x\n",
				    PCI_MAPREG_MEM_ADDR(reg));

				break;
			case PCI_MAPREG_MEM_TYPE_64BIT:
				mem = reg;
				bar += 0x04;
				if (pci_read(bus, dev, func, bar, &reg) != 0)
					warn("unable to read 0x%02x", bar);

				mem |= (u_int64_t)reg << 32;

				printf("64bit addr: 0x%016llx\n",
				    PCI_MAPREG_MEM64_ADDR(mem));

				break;
			}
			break;

		case PCI_MAPREG_TYPE_IO:
			printf("io addr: 0x%08x\n",
			    PCI_MAPREG_IO_ADDR(reg));
			break;
		}
	}

	if (pci_read(bus, dev, func, PCI_CARDBUS_CIS_REG, &reg) != 0)
		warn("unable to read PCI_CARDBUS_CIS_REG");
	printf("\t0x%04x: Cardbus CIS: %08x\n", PCI_CARDBUS_CIS_REG, reg);

	if (pci_read(bus, dev, func, PCI_SUBSYS_ID_REG, &reg) != 0)
		warn("unable to read PCI_SUBSYS_ID_REG");
	printf("\t0x%04x: Subsystem Vendor ID: %04x Product ID: %04x\n",
	    PCI_SUBSYS_ID_REG, PCI_VENDOR(reg), PCI_PRODUCT(reg));

	if (pci_read(bus, dev, func, PCI_ROM_REG, &reg) != 0)
		warn("unable to read PCI_ROM_REG");
	printf("\t0x%04x: Expansion ROM Base Address: %08x\n",
	    PCI_ROM_REG, reg);

	if (pci_read(bus, dev, func, 0x38, &reg) != 0)
		warn("unable to read 0x38 (reserved)");
	printf("\t0x%04x: %08x\n", 0x38, reg);

	if (pci_read(bus, dev, func, PCI_INTERRUPT_REG, &reg) != 0)
		warn("unable to read PCI_INTERRUPT_REG");
	printf("\t0x%04x: Interrupt Pin: %02x Line: %02x Min Gnt: %02x"
	    " Max Lat: %02x\n", PCI_INTERRUPT_REG, PCI_INTERRUPT_PIN(reg),
	    PCI_INTERRUPT_LINE(reg), PCI_MIN_GNT(reg), PCI_MAX_LAT(reg));
}

void
dump_type1(int bus, int dev, int func)
{
	u_int32_t reg;
	int bar;

	for (bar = PCI_MAPREG_START; bar < PCI_MAPREG_PPB_END; bar += 0x4) {
		if (pci_read(bus, dev, func, bar, &reg) != 0)
			warn("unable to read PCI_MAPREG 0x%02x", bar);
		printf("\t0x%04x: %08x\n", bar, reg);
	}

	if (pci_read(bus, dev, func, PCI_PRIBUS_1, &reg) != 0)
		warn("unable to read PCI_PRIBUS_1");
	printf("\t0x%04x: Primary Bus: %d Secondary Bus: %d "
	    "Subordinate Bus: %d \n\t        Secondary Latency Timer: %02x\n",
	    PCI_PRIBUS_1, (reg >> 0) & 0xff, (reg >> 8) & 0xff,
	    (reg >> 16) & 0xff, (reg >> 24) & 0xff);

	if (pci_read(bus, dev, func, PCI_IOBASEL_1, &reg) != 0)
		warn("unable to read PCI_IOBASEL_1");
	printf("\t0x%04x: I/O Base: %02x I/O Limit: %02x "
	    "Secondary Status: %04x\n", PCI_IOBASEL_1, (reg >> 0 ) & 0xff,
	    (reg >> 8) & 0xff, (reg >> 16) & 0xffff);

	if (pci_read(bus, dev, func, PCI_MEMBASE_1, &reg) != 0)
		warn("unable to read PCI_MEMBASE_1");
	printf("\t0x%04x: Memory Base: %04x Memory Limit: %04x\n",
	    PCI_MEMBASE_1, (reg >> 0) & 0xffff, (reg >> 16) & 0xffff);

	if (pci_read(bus, dev, func, PCI_PMBASEL_1, &reg) != 0)
		warn("unable to read PCI_PMBASEL_1");
	printf("\t0x%04x: Prefetch Memory Base: %04x "
	    "Prefetch Memory Limit: %04x\n", PCI_PMBASEL_1,
	    (reg >> 0) & 0xffff, (reg >> 16) & 0xffff);

#undef PCI_PMBASEH_1
#define PCI_PMBASEH_1	0x28
	if (pci_read(bus, dev, func, PCI_PMBASEH_1, &reg) != 0)
		warn("unable to read PCI_PMBASEH_1");
	printf("\t0x%04x: Prefetch Memory Base Upper 32 Bits: %08x\n",
	    PCI_PMBASEH_1, reg);

#undef PCI_PMLIMITH_1
#define PCI_PMLIMITH_1	0x2c
	if (pci_read(bus, dev, func, PCI_PMLIMITH_1, &reg) != 0)
		warn("unable to read PCI_PMLIMITH_1");
	printf("\t0x%04x: Prefetch Memory Limit Upper 32 Bits: %08x\n",
	    PCI_PMLIMITH_1, reg);

#undef PCI_IOBASEH_1
#define PCI_IOBASEH_1	0x30
	if (pci_read(bus, dev, func, PCI_IOBASEH_1, &reg) != 0)
		warn("unable to read PCI_IOBASEH_1");
	printf("\t0x%04x: I/O Base Upper 16 Bits: %04x "
	    "I/O Limit Upper 16 Bits: %04x\n", PCI_IOBASEH_1,
	    (reg >> 0) & 0xffff, (reg >> 16) & 0xffff);

#define PCI_PPB_ROM_REG		0x38
	if (pci_read(bus, dev, func, PCI_PPB_ROM_REG, &reg) != 0)
		warn("unable to read PCI_PPB_ROM_REG");
	printf("\t0x%04x: Expansion ROM Base Address: %08x\n",
	    PCI_PPB_ROM_REG, reg);

	if (pci_read(bus, dev, func, PCI_INTERRUPT_REG, &reg) != 0)
		warn("unable to read PCI_INTERRUPT_REG");
	printf("\t0x%04x: Interrupt Pin: %02x Line: %02x "
	    "Bridge Control: %04x\n",
	    PCI_INTERRUPT_REG, PCI_INTERRUPT_PIN(reg),
	    PCI_INTERRUPT_LINE(reg), reg >> 16);
}

void
dump_type2(int bus, int dev, int func)
{
	u_int32_t reg;

	if (pci_read(bus, dev, func, PCI_MAPREG_START, &reg) != 0)
		warn("unable to read PCI_MAPREG\n");
	printf("\t0x%04x: Cardbus Control Registers Base Address: %08x\n",
	    PCI_MAPREG_START, reg);

	if (pci_read(bus, dev, func, PCI_PRIBUS_2, &reg) != 0)
		warn("unable to read PCI_PRIBUS_2");
	printf("\t0x%04x: Primary Bus: %d Cardbus Bus: %d "
	    "Subordinate Bus: %d \n\t        Cardbus Latency Timer: %02x\n",
	    PCI_PRIBUS_2, (reg >> 0) & 0xff, (reg >> 8) & 0xff,
	    (reg >> 16) & 0xff, (reg >> 24) & 0xff);

	if (pci_read(bus, dev, func, PCI_MEMBASE0_2, &reg) != 0)
		warn("unable to read PCI_MEMBASE0_2\n");
	printf("\t0x%04x: Memory Base 0: %08x\n", PCI_MEMBASE0_2, reg);

	if (pci_read(bus, dev, func, PCI_MEMLIMIT0_2, &reg) != 0)
		warn("unable to read PCI_MEMLIMIT0_2\n");
	printf("\t0x%04x: Memory Limit 0: %08x\n", PCI_MEMLIMIT0_2, reg);

	if (pci_read(bus, dev, func, PCI_MEMBASE1_2, &reg) != 0)
		warn("unable to read PCI_MEMBASE1_2\n");
	printf("\t0x%04x: Memory Base 1: %08x\n", PCI_MEMBASE1_2, reg);

	if (pci_read(bus, dev, func, PCI_MEMLIMIT1_2, &reg) != 0)
		warn("unable to read PCI_MEMLIMIT1_2\n");
	printf("\t0x%04x: Memory Limit 1: %08x\n", PCI_MEMLIMIT1_2, reg);

	if (pci_read(bus, dev, func, PCI_IOBASE0_2, &reg) != 0)
		warn("unable to read PCI_IOBASE0_2\n");
	printf("\t0x%04x: I/O Base 0: %08x\n", PCI_IOBASE0_2, reg);

	if (pci_read(bus, dev, func, PCI_IOLIMIT0_2, &reg) != 0)
		warn("unable to read PCI_IOLIMIT0_2\n");
	printf("\t0x%04x: I/O Limit 0: %08x\n", PCI_IOLIMIT0_2, reg);

	if (pci_read(bus, dev, func, PCI_IOBASE1_2, &reg) != 0)
		warn("unable to read PCI_IOBASE1_2\n");
	printf("\t0x%04x: I/O Base 1: %08x\n", PCI_IOBASE1_2, reg);

	if (pci_read(bus, dev, func, PCI_IOLIMIT1_2, &reg) != 0)
		warn("unable to read PCI_IOLIMIT1_2\n");
	printf("\t0x%04x: I/O Limit 1: %08x\n", PCI_IOLIMIT1_2, reg);

	if (pci_read(bus, dev, func, PCI_INTERRUPT_REG, &reg) != 0)
		warn("unable to read PCI_INTERRUPT_REG");
	printf("\t0x%04x: Interrupt Pin: %02x Line: %02x "
	    "Bridge Control: %04x\n",
	    PCI_INTERRUPT_REG, PCI_INTERRUPT_PIN(reg),
	    PCI_INTERRUPT_LINE(reg), reg >> 16);

	if (pci_read(bus, dev, func, PCI_SUBVEND_2, &reg) != 0)
		warn("unable to read PCI_SUBVEND_2");
	printf("\t0x%04x: Subsystem Vendor ID: %04x Product ID: %04x\n",
	    PCI_SUBVEND_2, PCI_VENDOR(reg), PCI_PRODUCT(reg));

	if (pci_read(bus, dev, func, PCI_PCCARDIF_2, &reg) != 0)
		warn("unable to read PCI_PCCARDIF_2\n");
	printf("\t0x%04x: 16-bit Legacy Mode Base Address: %08x\n",
	    PCI_PCCARDIF_2, reg);
}

void
dump(int bus, int dev, int func)
{
	u_int32_t reg;
	u_int8_t capptr = PCI_CAPLISTPTR_REG;

	if (pci_read(bus, dev, func, PCI_ID_REG, &reg) != 0)
		warn("unable to read PCI_ID_REG");
	printf("\t0x%04x: Vendor ID: %04x Product ID: %04x\n", PCI_ID_REG,
	    PCI_VENDOR(reg), PCI_PRODUCT(reg));

	if (pci_read(bus, dev, func, PCI_COMMAND_STATUS_REG, &reg) != 0)
		warn("unable to read PCI_COMMAND_STATUS_REG");
	printf("\t0x%04x: Command: %04x Status ID: %04x\n",
	    PCI_COMMAND_STATUS_REG, reg & 0xffff, (reg  >> 16) & 0xffff);

	if (pci_read(bus, dev, func, PCI_CLASS_REG, &reg) != 0)
		warn("unable to read PCI_CLASS_REG");
	printf("\t0x%04x: Class: %02x Subclass: %02x Interface: %02x "
	    "Revision: %02x\n", PCI_CLASS_REG, PCI_CLASS(reg),
	    PCI_SUBCLASS(reg), PCI_INTERFACE(reg), PCI_REVISION(reg));

	if (pci_read(bus, dev, func, PCI_BHLC_REG, &reg) != 0)
		warn("unable to read PCI_BHLC_REG");
	printf("\t0x%04x: BIST: %02x Header Type: %02x Latency Timer: %02x "
	    "Cache Line Size: %02x\n", PCI_BHLC_REG, PCI_BIST(reg),
	    PCI_HDRTYPE(reg), PCI_LATTIMER(reg), PCI_CACHELINE(reg));

	switch (PCI_HDRTYPE_TYPE(reg)) {
	case 2:
		dump_type2(bus, dev, func);
		capptr = PCI_CARDBUS_CAPLISTPTR_REG;
		break;
	case 1:
		dump_type1(bus, dev, func);
		break;
	case 0:
		dump_type0(bus, dev, func);
		break;
	default:
		break;
	}
	dump_caplist(bus, dev, func, capptr);
}

void
hexdump(int bus, int dev, int func, int full)
{
	u_int32_t reg;
	int i;

	for (i = 0; i < (full ? 256 : 64); i += 4) {
		if ((i % 16) == 0)
			printf("\t0x%04x:", i);

		if (pci_read(bus, dev, func, i, &reg) != 0)
			warn("unable to read 0x%02x", i);
		printf(" %08x", reg);

		if ((i % 16) == 12)
			printf("\n");
	}
}

int
pci_nfuncs(int bus, int dev)
{
	u_int32_t hdr;

	if (pci_read(bus, dev, 0, PCI_BHLC_REG, &hdr) != 0)
		return (-1);

	return (PCI_HDRTYPE_MULTIFN(hdr) ? 8 : 1);
}

int
pci_read(int bus, int dev, int func, u_int32_t reg, u_int32_t *val)
{
	struct pci_io io;
	int rv;

	bzero(&io, sizeof(io));
	io.pi_sel.pc_bus = bus;
	io.pi_sel.pc_dev = dev;
	io.pi_sel.pc_func = func;
	io.pi_reg = reg;
	io.pi_width = 4;

	rv = ioctl(pcifd, PCIOCREAD, &io);
	if (rv != 0)
		return (rv);

	*val = io.pi_data;

	return (0);
}

int
dump_rom(int bus, int dev, int func)
{
	struct pci_rom rom;
	u_int32_t cr, addr;

	if (pci_read(bus, dev, func, PCI_ROM_REG, &addr) != 0 ||
	    pci_read(bus, dev, func, PCI_CLASS_REG, &cr) != 0)
		return (errno);

	if (addr == 0 && PCI_CLASS(cr) == PCI_CLASS_DISPLAY &&
	    PCI_SUBCLASS(cr) == PCI_SUBCLASS_DISPLAY_VGA)
		return dump_vga_bios();

	bzero(&rom, sizeof(rom));
	rom.pr_sel.pc_bus = bus;
	rom.pr_sel.pc_dev = dev;
	rom.pr_sel.pc_func = func;
	if (ioctl(pcifd, PCIOCGETROMLEN, &rom))
		return (errno);

	rom.pr_rom = malloc(rom.pr_romlen);
	if (rom.pr_rom == NULL)
		return (ENOMEM);

	if (ioctl(pcifd, PCIOCGETROM, &rom))
		return (errno);

	if (write(romfd, rom.pr_rom, rom.pr_romlen) == -1)
		return (errno);

	return (0);
}

#define VGA_BIOS_ADDR	0xc0000
#define VGA_BIOS_LEN	0x10000

int
dump_vga_bios(void)
{
#if defined(__amd64__) || defined(__i386__)
	void *bios;
	int fd;

	fd = open(_PATH_MEM, O_RDONLY, 0777);
	if (fd == -1)
		err(1, "%s", _PATH_MEM);

	bios = malloc(VGA_BIOS_LEN);
	if (bios == NULL)
		return (ENOMEM);

	if (pread(fd, bios, VGA_BIOS_LEN, VGA_BIOS_ADDR) == -1)
		err(1, "%s", _PATH_MEM);

	if (write(romfd, bios, VGA_BIOS_LEN) == -1)
		return (errno);

	return (0);
#else
	return (ENODEV);
#endif
}