Update NetBSD support.

Signed-off-by: Michael Lorenz <macallan@NetBSD.org>
Signed-off-by: Thomas Klausner <wiz@NetBSD.org>
Reviewed-by: Matthieu Herrb <matthieu.herrb@laas.fr>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>

2 files changed, 342 insertions, 133 deletions

diff --git a/configure.ac b/configure.ac
index 91374e5..3441b63 100644
--- a/configure.ac
+++ b/configure.ac
@@ -77,10 +77,10 @@ case $host_os in
 	*netbsd*)
 		case $host in
 		*i386*)
-			PCIACCESS_LIBS="-li386"
+			PCIACCESS_LIBS="-li386 -lpci"
 			;;
 		*x86_64*|*amd64*)
-			PCIACCESS_LIBS="-lx86_64"
+			PCIACCESS_LIBS="-lx86_64 -lpci"
 			;;
 		esac
 		netbsd=yes
diff --git a/src/netbsd_pci.c b/src/netbsd_pci.c
index 63585e3..3566d7b 100644
--- a/src/netbsd_pci.c
+++ b/src/netbsd_pci.c
@@ -1,6 +1,7 @@
 /*
  * Copyright (c) 2008 Juan Romero Pardines
  * Copyright (c) 2008 Mark Kettenis
+ * Copyright (c) 2009 Michael Lorenz
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -20,12 +21,15 @@
 #include <sys/mman.h>
 #include <sys/types.h>
 
+#ifdef HAVE_MTRR
 #include <machine/sysarch.h>
 #include <machine/mtrr.h>
+#define netbsd_set_mtrr(mr, num)	_X86_SYSARCH_L(set_mtrr)(mr, num)
+#endif
 
+#include <dev/pci/pcidevs.h>
 #include <dev/pci/pciio.h>
 #include <dev/pci/pcireg.h>
-#include <dev/pci/pcidevs.h>
 
 #include <errno.h>
 #include <fcntl.h>
@@ -35,126 +39,152 @@
 #include <unistd.h>
 
 
+#include <pci.h>
+#include <dev/wscons/wsconsio.h>
+
 #include "pciaccess.h"
 #include "pciaccess_private.h"
 
-static int pcifd;
+typedef struct _pcibus {
+	int fd;		/* /dev/pci* */
+	int num;	/* bus number */
+	int maxdevs;	/* maximum number of devices */
+} PciBus;
+
+static PciBus buses[32];	/* indexed by pci_device.domain */
+static int nbuses = 0;		/* number of buses found */
+
+/*
+ * NetBSD's userland has a /dev/pci* entry for each bus but userland has no way
+ * to tell if a bus is a subordinate of another one or if it's on a different
+ * host bridge. On some architectures ( macppc for example ) all root buses have
+ * bus number 0 but on sparc64 for example the two roots in an Ultra60 have
+ * different bus numbers - one is 0 and the other 128.
+ * With each /dev/pci* we can map everything on the same root and we can also
+ * see all devices on the same root, trying to do that causes problems though:
+ * - since we can't tell which /dev/pci* is a subordinate we would find some
+ *   devices more than once
+ * - we would have to guess subordinate bus numbers which is a waste of time
+ *   since we can ask each /dev/pci* for its bus number so we can scan only the
+ *   buses we know exist, not all 256 which may exist in each domain.
+ * - some bus_space_mmap() methods may limit mappings to address ranges which
+ *   belong to known devices on that bus only.
+ * Each host bridge may or may not have its own IO range, to avoid guesswork
+ * here each /dev/pci* will let userland map its appropriate IO range at
+ * PCI_MAGIC_IO_RANGE if defined in <machine/param.h>
+ * With all this we should be able to use any PCI graphics device on any PCI
+ * bus on any architecture as long as Xorg has a driver, without allowing
+ * arbitrary mappings via /dev/mem and without userland having to know or care
+ * about translating bus addresses to physical addresses or the other way
+ * around.
+ */
 
 static int
-pci_read(int bus, int dev, int func, uint32_t reg, uint32_t *val)
+pci_read(int domain, int bus, int dev, int func, uint32_t reg, uint32_t *val)
 {
-	struct pciio_bdf_cfgreg io;
-	int err;
+	uint32_t rval;
 
-	bzero(&io, sizeof(io));
-	io.bus = bus;
-	io.device = dev;
-	io.function = func;
-	io.cfgreg.reg = reg;
+	if ((domain < 0) || (domain > nbuses))
+		return -1;
 
-	err = ioctl(pcifd, PCI_IOC_BDF_CFGREAD, &io);
-	if (err)
-		return (err);
+	if (pcibus_conf_read(buses[domain].fd, (unsigned int)bus,
+	    (unsigned int)dev, (unsigned int)func, reg, &rval) == -1)
+		return (-1);
 
-	*val = io.cfgreg.val;
+	*val = rval;
 
 	return 0;
 }
 
 static int
-pci_write(int bus, int dev, int func, uint32_t reg, uint32_t val)
+pci_write(int domain, int bus, int dev, int func, uint32_t reg, uint32_t val)
 {
-	struct pciio_bdf_cfgreg io;
 
-	bzero(&io, sizeof(io));
-	io.bus = bus;
-	io.device = dev;
-	io.function = func;
-	io.cfgreg.reg = reg;
-	io.cfgreg.val = val;
+	if ((domain < 0) || (domain > nbuses))
+		return -1;
 
-	return ioctl(pcifd, PCI_IOC_BDF_CFGWRITE, &io);
+	return pcibus_conf_write(buses[domain].fd, (unsigned int)bus,
+	    (unsigned int)dev, (unsigned int)func, reg, val);
 }
 
 static int
-pci_nfuncs(int bus, int dev)
+pci_nfuncs(int domain, int bus, int dev)
 {
 	uint32_t hdr;
 
-	if (pci_read(bus, dev, 0, PCI_BHLC_REG, &hdr) != 0)
+	if ((domain < 0) || (domain > nbuses))
+		return -1;
+
+	if (pci_read(domain, bus, dev, 0, PCI_BHLC_REG, &hdr) != 0)
 		return -1;
 
 	return (PCI_HDRTYPE_MULTIFN(hdr) ? 8 : 1);
 }
 
+/*ARGSUSED*/
 static int
 pci_device_netbsd_map_range(struct pci_device *dev,
     struct pci_device_mapping *map)
 {
-	struct mtrr mtrr;
-	int fd, error, nmtrr, prot = PROT_READ;
+#ifdef HAVE_MTRR
+	struct mtrr m;
+	int n = 1;
+#endif
+	int prot, ret = 0;
 
-	if ((fd = open("/dev/mem", O_RDWR | O_CLOEXEC)) == -1)
-		return errno;
+	prot = PROT_READ;
 
 	if (map->flags & PCI_DEV_MAP_FLAG_WRITABLE)
 		prot |= PROT_WRITE;
-
-	map->memory = mmap(NULL, map->size, prot, MAP_SHARED,
-	    fd, map->base);
+	map->memory = mmap(NULL, (size_t)map->size, prot, MAP_SHARED,
+	    buses[dev->domain].fd, (off_t)map->base);
 	if (map->memory == MAP_FAILED)
 		return errno;
 
+#ifdef HAVE_MTRR
+	memset(&m, 0, sizeof(m));
+
 	/* No need to set an MTRR if it's the default mode. */
 	if ((map->flags & PCI_DEV_MAP_FLAG_CACHABLE) ||
 	    (map->flags & PCI_DEV_MAP_FLAG_WRITE_COMBINE)) {
-		mtrr.base = map->base;
-		mtrr.len = map->size;
-		mtrr.flags = MTRR_VALID;
-
+		m.base = map->base;
+		m.flags = MTRR_VALID | MTRR_PRIVATE;
+		m.len = map->size;
+		m.owner = getpid();
 		if (map->flags & PCI_DEV_MAP_FLAG_CACHABLE)
-			mtrr.type = MTRR_TYPE_WB;
+			m.type = MTRR_TYPE_WB;
 		if (map->flags & PCI_DEV_MAP_FLAG_WRITE_COMBINE)
-			mtrr.type = MTRR_TYPE_WC;
-#ifdef __i386__
-		error = i386_set_mtrr(&mtrr, &nmtrr);
-#endif
-#ifdef __amd64__
-		error = x86_64_set_mtrr(&mtrr, &nmtrr);
-#endif
-		if (error) {
-			close(fd);
-			return errno;
+			m.type = MTRR_TYPE_WC;
+
+		if ((netbsd_set_mtrr(&m, &n)) == -1) {
+			fprintf(stderr, "mtrr set failed: %s\n",
+			    strerror(errno));
 		}
 	}
+#endif
 
-	close(fd);
-
-	return 0;
+	return ret;
 }
 
 static int
 pci_device_netbsd_unmap_range(struct pci_device *dev,
     struct pci_device_mapping *map)
 {
-	struct mtrr mtrr;
-	int nmtrr, error;
+#ifdef HAVE_MTRR
+	struct mtrr m;
+	int n = 1;
+
+	memset(&m, 0, sizeof(m));
 
 	if ((map->flags & PCI_DEV_MAP_FLAG_CACHABLE) ||
 	    (map->flags & PCI_DEV_MAP_FLAG_WRITE_COMBINE)) {
-		mtrr.base = map->base;
-		mtrr.len = map->size;
-		mtrr.type = MTRR_TYPE_UC;
-		mtrr.flags = 0; /* clear/set MTRR */
-#ifdef __i386__
-		error = i386_set_mtrr(&mtrr, &nmtrr);
-#endif
-#ifdef __amd64__
-		error = x86_64_set_mtrr(&mtrr, &nmtrr);
-#endif
-		if (error)
-			return errno;
+		m.base = map->base;
+		m.flags = 0;
+		m.len = map->size;
+		m.type = MTRR_TYPE_UC;
+		(void)netbsd_set_mtrr(&m, &n);
 	}
+#endif
 
 	return pci_device_generic_unmap_range(dev, map);
 }
@@ -163,25 +193,23 @@ static int
 pci_device_netbsd_read(struct pci_device *dev, void *data,
     pciaddr_t offset, pciaddr_t size, pciaddr_t *bytes_read)
 {
-	struct pciio_bdf_cfgreg io;
-
-	io.bus = dev->bus;
-	io.device = dev->dev;
-	io.function = dev->func;
+	u_int reg, rval;
 
 	*bytes_read = 0;
 	while (size > 0) {
-		int toread = MIN(size, 4 - (offset & 0x3));
+		size_t toread = MIN(size, 4 - (offset & 0x3));
 
-		io.cfgreg.reg = (offset & ~0x3);
+		reg = (u_int)(offset & ~0x3);
 
-		if (ioctl(pcifd, PCI_IOC_BDF_CFGREAD, &io) == -1)
+		if ((pcibus_conf_read(buses[dev->domain].fd,
+		    (unsigned int)dev->bus, (unsigned int)dev->dev,
+		    (unsigned int)dev->func, reg, &rval)) == -1)
 			return errno;
 
-		io.cfgreg.val = htole32(io.cfgreg.val);
-		io.cfgreg.val >>= ((offset & 0x3) * 8);
+		rval = htole32(rval);
+		rval >>= ((offset & 0x3) * 8);
 
-		memcpy(data, &io.cfgreg.val, toread);
+		memcpy(data, &rval, toread);
 
 		offset += toread;
 		data = (char *)data + toread;
@@ -196,25 +224,23 @@ static int
 pci_device_netbsd_write(struct pci_device *dev, const void *data,
     pciaddr_t offset, pciaddr_t size, pciaddr_t *bytes_written)
 {
-	struct pciio_bdf_cfgreg io;
+	u_int reg, val;
 
 	if ((offset % 4) != 0 || (size % 4) != 0)
 		return EINVAL;
 
-	io.bus = dev->bus;
-	io.device = dev->dev;
-	io.function = dev->func;
-
 	*bytes_written = 0;
 	while (size > 0) {
-		io.cfgreg.reg = offset;
-		memcpy(&io.cfgreg.val, data, 4);
+		reg = (u_int)offset;
+		memcpy(&val, data, 4);
 
-		if (ioctl(pcifd, PCI_IOC_BDF_CFGWRITE, &io) == -1)
+		if ((pcibus_conf_write(buses[dev->domain].fd,
+		    (unsigned int)dev->bus, (unsigned int)dev->dev,
+		    (unsigned int)dev->func, reg, val)) == -1)
 			return errno;
 
 		offset += 4;
-		data = (char *)data + 4;
+		data = (const char *)data + 4;
 		size -= 4;
 		*bytes_written += 4;
 	}
@@ -222,10 +248,51 @@ pci_device_netbsd_write(struct pci_device *dev, const void *data,
 	return 0;
 }
 
+static int
+pci_device_netbsd_boot_vga(struct pci_device *dev)
+{
+	int ret;
+	struct wsdisplayio_bus_id busid;
+	int fd;
+
+	fd = open("/dev/ttyE0", O_RDONLY);
+	if (fd == -1) {
+		fprintf(stderr, "failed to open /dev/ttyE0: %s\n",
+		    strerror(errno));
+		return 0;
+	}
+
+	ret = ioctl(fd, WSDISPLAYIO_GET_BUSID, &busid);
+	close(fd);
+	if (ret == -1) {
+		fprintf(stderr, "ioctl WSDISPLAYIO_GET_BUSID failed: %s\n",
+		    strerror(errno));
+		return 0;
+	}
+
+	if (busid.bus_type != WSDISPLAYIO_BUS_PCI)
+		return 0;
+
+	if (busid.ubus.pci.domain != dev->domain)
+		return 0;
+	if (busid.ubus.pci.bus != dev->bus)
+		return 0;
+	if (busid.ubus.pci.device != dev->dev)
+		return 0;
+	if (busid.ubus.pci.function != dev->func)
+		return 0;
+
+	return 1;
+}
+
 static void
 pci_system_netbsd_destroy(void)
 {
-	close(pcifd);
+	int i;
+
+	for (i = 0; i < nbuses; i++) {
+		close(buses[i].fd);
+	}
 	free(pci_sys);
 	pci_sys = NULL;
 }
@@ -233,17 +300,34 @@ pci_system_netbsd_destroy(void)
 static int
 pci_device_netbsd_probe(struct pci_device *device)
 {
-	struct pci_device_private *priv = (struct pci_device_private *)device;
+	struct pci_device_private *priv =
+	    (struct pci_device_private *)(void *)device;
 	struct pci_mem_region *region;
 	uint64_t reg64, size64;
 	uint32_t bar, reg, size;
-	int bus, dev, func, err;
+	int bus, dev, func, err, domain;
 
+	domain = device->domain;
 	bus = device->bus;
 	dev = device->dev;
 	func = device->func;
 
-	err = pci_read(bus, dev, func, PCI_BHLC_REG, &reg);
+	/* Enable the device if necessary */
+	err = pci_read(domain, bus, dev, func, PCI_COMMAND_STATUS_REG, &reg);
+	if (err)
+		return err;
+	if ((reg & (PCI_COMMAND_IO_ENABLE | PCI_COMMAND_MEM_ENABLE | PCI_COMMAND_MASTER_ENABLE)) !=
+	    (PCI_COMMAND_IO_ENABLE | PCI_COMMAND_MEM_ENABLE | PCI_COMMAND_MASTER_ENABLE)) {
+		reg |= PCI_COMMAND_IO_ENABLE |
+		       PCI_COMMAND_MEM_ENABLE |
+		       PCI_COMMAND_MASTER_ENABLE;
+		err = pci_write(domain, bus, dev, func, PCI_COMMAND_STATUS_REG,
+				reg);
+		if (err)
+			return err;
+	}
+
+	err = pci_read(domain, bus, dev, func, PCI_BHLC_REG, &reg);
 	if (err)
 		return err;
 
@@ -254,16 +338,16 @@ pci_device_netbsd_probe(struct pci_device *device)
 	region = device->regions;
 	for (bar = PCI_MAPREG_START; bar < PCI_MAPREG_END;
 	     bar += sizeof(uint32_t), region++) {
-		err = pci_read(bus, dev, func, bar, &reg);
+		err = pci_read(domain, bus, dev, func, bar, &reg);
 		if (err)
 			return err;
 
 		/* Probe the size of the region. */
-		err = pci_write(bus, dev, func, bar, ~0);
+		err = pci_write(domain, bus, dev, func, bar, (unsigned int)~0);
 		if (err)
 			return err;
-		pci_read(bus, dev, func, bar, &size);
-		pci_write(bus, dev, func, bar, reg);
+		pci_read(domain, bus, dev, func, bar, &size);
+		pci_write(domain, bus, dev, func, bar, reg);
 
 		if (PCI_MAPREG_TYPE(reg) == PCI_MAPREG_TYPE_IO) {
 			region->is_IO = 1;
@@ -286,66 +370,185 @@ pci_device_netbsd_probe(struct pci_device *device)
 
 				bar += sizeof(uint32_t);
 
-				err = pci_read(bus, dev, func, bar, &reg);
+				err = pci_read(domain, bus, dev, func, bar, &reg);
 				if (err)
 					return err;
 				reg64 |= (uint64_t)reg << 32;
 
-				err = pci_write(bus, dev, func, bar, ~0);
+				err = pci_write(domain, bus, dev, func, bar,
+				    (unsigned int)~0);
 				if (err)
 					return err;
-				pci_read(bus, dev, func, bar, &size);
-				pci_write(bus, dev, func, bar, reg64 >> 32);
+				pci_read(domain, bus, dev, func, bar, &size);
+				pci_write(domain, bus, dev, func, bar,
+				    (unsigned int)(reg64 >> 32));
 				size64 |= (uint64_t)size << 32;
 
-				region->base_addr = PCI_MAPREG_MEM64_ADDR(reg64);
-				region->size = PCI_MAPREG_MEM64_SIZE(size64);
+				region->base_addr =
+				    (unsigned long)PCI_MAPREG_MEM64_ADDR(reg64);
+				region->size =
+				    (unsigned long)PCI_MAPREG_MEM64_SIZE(size64);
 				region++;
 				break;
 			}
 		}
 	}
 
+	/* Probe expansion ROM if present */
+	err = pci_read(domain, bus, dev, func, PCI_MAPREG_ROM, &reg);
+	if (err)
+		return err;
+	if (reg != 0) {
+		err = pci_write(domain, bus, dev, func, PCI_MAPREG_ROM,
+		    (uint32_t)(~PCI_MAPREG_ROM_ENABLE));
+		if (err)
+			return err;
+		pci_read(domain, bus, dev, func, PCI_MAPREG_ROM, &size);
+		pci_write(domain, bus, dev, func, PCI_MAPREG_ROM, reg);
+		if ((reg & PCI_MAPREG_MEM_ADDR_MASK) != 0) {
+			priv->rom_base = reg & PCI_MAPREG_MEM_ADDR_MASK;
+			device->rom_size = -(size & PCI_MAPREG_MEM_ADDR_MASK);
+		}
+	}
+
 	return 0;
 }
 
+/**
+ * Read a VGA rom using the 0xc0000 mapping.
+ *
+ * This function should be extended to handle access through PCI resources,
+ * which should be more reliable when available.
+ */
+static int
+pci_device_netbsd_read_rom(struct pci_device *dev, void *buffer)
+{
+    struct pci_device_private *priv = (struct pci_device_private *)(void *)dev;
+    void *bios;
+    pciaddr_t rom_base;
+    size_t rom_size;
+    uint32_t bios_val, command_val;
+    int pci_rom;
+
+    if (((priv->base.device_class >> 16) & 0xff) != PCI_CLASS_DISPLAY ||
+	((priv->base.device_class >> 8) & 0xff) != PCI_SUBCLASS_DISPLAY_VGA)
+	return ENOSYS;
+
+    if (priv->rom_base == 0) {
+#if defined(__amd64__) || defined(__i386__)
+	/*
+	 * We need a way to detect when this isn't the console and reject
+	 * this request outright.
+	 */
+	rom_base = 0xc0000;
+	rom_size = 0x10000;
+	pci_rom = 0;
+#else
+	return ENOSYS;
+#endif
+    } else {
+	rom_base = priv->rom_base;
+	rom_size = dev->rom_size;
+	pci_rom = 1;
+	if ((pcibus_conf_read(buses[dev->domain].fd, (unsigned int)dev->bus,
+	    (unsigned int)dev->dev, (unsigned int)dev->func,
+	    PCI_COMMAND_STATUS_REG, &command_val)) == -1)
+	    return errno;
+	if ((command_val & PCI_COMMAND_MEM_ENABLE) == 0) {
+	    if ((pcibus_conf_write(buses[dev->domain].fd,
+	        (unsigned int)dev->bus, (unsigned int)dev->dev,
+		(unsigned int)dev->func, PCI_COMMAND_STATUS_REG,
+		command_val | PCI_COMMAND_MEM_ENABLE)) == -1)
+		return errno;
+	}
+	if ((pcibus_conf_read(buses[dev->domain].fd, (unsigned int)dev->bus,
+	    (unsigned int)dev->dev, (unsigned int)dev->func,
+	    PCI_MAPREG_ROM, &bios_val)) == -1)
+	    return errno;
+	if ((bios_val & PCI_MAPREG_ROM_ENABLE) == 0) {
+	    if ((pcibus_conf_write(buses[dev->domain].fd,
+	        (unsigned int)dev->bus,
+		(unsigned int)dev->dev, (unsigned int)dev->func,
+		PCI_MAPREG_ROM, bios_val | PCI_MAPREG_ROM_ENABLE)) == -1)
+		return errno;
+	}
+    }
+
+    fprintf(stderr, "Using rom_base = 0x%lx 0x%lx (pci_rom=%d)\n",
+        (long)rom_base, (long)rom_size, pci_rom);
+
+    bios = mmap(NULL, rom_size, PROT_READ, MAP_SHARED, buses[dev->domain].fd,
+        (off_t)rom_base);
+    if (bios == MAP_FAILED) {
+	int serrno = errno;
+	return serrno;
+    }
+
+    memcpy(buffer, bios, rom_size);
+
+    munmap(bios, rom_size);
+
+    if (pci_rom) {
+	if ((command_val & PCI_COMMAND_MEM_ENABLE) == 0) {
+	    if ((pcibus_conf_write(buses[dev->domain].fd,
+	        (unsigned int)dev->bus,
+		(unsigned int)dev->dev, (unsigned int)dev->func,
+		PCI_COMMAND_STATUS_REG, command_val)) == -1)
+		return errno;
+	}
+	if ((bios_val & PCI_MAPREG_ROM_ENABLE) == 0) {
+	    if ((pcibus_conf_write(buses[dev->domain].fd,
+	        (unsigned int)dev->bus,
+		(unsigned int)dev->dev, (unsigned int)dev->func,
+		PCI_MAPREG_ROM, bios_val)) == -1)
+		return errno;
+	}
+    }
+
+    return 0;
+}
+
 static const struct pci_system_methods netbsd_pci_methods = {
-	pci_system_netbsd_destroy,
-	NULL,
-	NULL,
-	pci_device_netbsd_probe,
-	pci_device_netbsd_map_range,
-	pci_device_netbsd_unmap_range,
-	pci_device_netbsd_read,
-	pci_device_netbsd_write,
-	pci_fill_capabilities_generic
+	.destroy = pci_system_netbsd_destroy,
+	.destroy_device = NULL,
+	.read_rom = pci_device_netbsd_read_rom,
+	.probe = pci_device_netbsd_probe,
+	.map_range = pci_device_netbsd_map_range,
+	.unmap_range = pci_device_netbsd_unmap_range,
+	.read = pci_device_netbsd_read,
+	.write = pci_device_netbsd_write,
+	.fill_capabilities = pci_fill_capabilities_generic,
+	.boot_vga = pci_device_netbsd_boot_vga,
 };
 
 int
 pci_system_netbsd_create(void)
 {
 	struct pci_device_private *device;
-	int bus, dev, func, ndevs, nfuncs;
+	int bus, dev, func, ndevs, nfuncs, domain, pcifd;
 	uint32_t reg;
-
-	pcifd = open("/dev/pci0", O_RDWR | O_CLOEXEC);
-	if (pcifd == -1)
-		return ENXIO;
+	char netbsd_devname[32];
+	struct pciio_businfo businfo;
 
 	pci_sys = calloc(1, sizeof(struct pci_system));
-	if (pci_sys == NULL) {
-		close(pcifd);
-		return ENOMEM;
-	}
 
 	pci_sys->methods = &netbsd_pci_methods;
 
 	ndevs = 0;
-	for (bus = 0; bus < 256; bus++) {
-		for (dev = 0; dev < 32; dev++) {
-			nfuncs = pci_nfuncs(bus, dev);
+	nbuses = 0;
+	snprintf(netbsd_devname, 32, "/dev/pci%d", nbuses);
+	pcifd = open(netbsd_devname, O_RDWR | O_CLOEXEC);
+	while (pcifd > 0) {
+		ioctl(pcifd, PCI_IOC_BUSINFO, &businfo);
+		buses[nbuses].fd = pcifd;
+		buses[nbuses].num = bus = businfo.busno;
+		buses[nbuses].maxdevs = businfo.maxdevs;
+		domain = nbuses;
+		nbuses++;
+		for (dev = 0; dev < businfo.maxdevs; dev++) {
+			nfuncs = pci_nfuncs(domain, bus, dev);
 			for (func = 0; func < nfuncs; func++) {
-				if (pci_read(bus, dev, func, PCI_ID_REG,
+				if (pci_read(domain, bus, dev, func, PCI_ID_REG,
 				    &reg) != 0)
 					continue;
 				if (PCI_VENDOR(reg) == PCI_VENDOR_INVALID ||
@@ -355,37 +558,43 @@ pci_system_netbsd_create(void)
 				ndevs++;
 			}
 		}
+		snprintf(netbsd_devname, 32, "/dev/pci%d", nbuses);
+		pcifd = open(netbsd_devname, O_RDWR);
 	}
 
 	pci_sys->num_devices = ndevs;
 	pci_sys->devices = calloc(ndevs, sizeof(struct pci_device_private));
 	if (pci_sys->devices == NULL) {
+		int i;
+
+		for (i = 0; i < nbuses; i++)
+			close(buses[i].fd);
 		free(pci_sys);
-		close(pcifd);
 		return ENOMEM;
 	}
 
 	device = pci_sys->devices;
-	for (bus = 0; bus < 256; bus++) {
-		for (dev = 0; dev < 32; dev++) {
-			nfuncs = pci_nfuncs(bus, dev);
+	for (domain = 0; domain < nbuses; domain++) {
+		bus = buses[domain].num;
+		for (dev = 0; dev < buses[domain].maxdevs; dev++) {
+			nfuncs = pci_nfuncs(domain, bus, dev);
 			for (func = 0; func < nfuncs; func++) {
-				if (pci_read(bus, dev, func, PCI_ID_REG,
-				    &reg) != 0)
+				if (pci_read(domain, bus, dev, func,
+				    PCI_ID_REG, &reg) != 0)
 					continue;
 				if (PCI_VENDOR(reg) == PCI_VENDOR_INVALID ||
 				    PCI_VENDOR(reg) == 0)
 					continue;
 
-				device->base.domain = 0;
+				device->base.domain = domain;
 				device->base.bus = bus;
 				device->base.dev = dev;
 				device->base.func = func;
 				device->base.vendor_id = PCI_VENDOR(reg);
 				device->base.device_id = PCI_PRODUCT(reg);
 
-				if (pci_read(bus, dev, func, PCI_CLASS_REG,
-				    &reg) != 0)
+				if (pci_read(domain, bus, dev, func,
+				    PCI_CLASS_REG, &reg) != 0)
 					continue;
 
 				device->base.device_class =
@@ -393,8 +602,8 @@ pci_system_netbsd_create(void)
 				    PCI_SUBCLASS(reg) << 8;
 				device->base.revision = PCI_REVISION(reg);
 
-				if (pci_read(bus, dev, func, PCI_SUBSYS_ID_REG,
-				    &reg) != 0)
+				if (pci_read(domain, bus, dev, func,
+				    PCI_SUBSYS_ID_REG, &reg) != 0)
 					continue;
 
 				device->base.subvendor_id = PCI_VENDOR(reg);