A driver for programming the AGP hardware. This is only very lightly

tested on Intel BX chipsets only. The other agp minidrivers are totally
untested.

The programming api is a subset of the Linux api and is only intended to
be enough for the X server to use. There is also an in-kernel api for the
use of other kernel modules such as the 3D DRI.

21 files changed, 5280 insertions, 0 deletions

diff --git a/sys/dev/agp/agp.c b/sys/dev/agp/agp.c
new file mode 100644
index 0000000..e1d6583
--- /dev/null
+++ b/sys/dev/agp/agp.c
@@ -0,0 +1,790 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#include "opt_bus.h"
+#include "opt_pci.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/kernel.h>
+#include <sys/bus.h>
+#include <sys/conf.h>
+#include <sys/ioccom.h>
+#include <sys/agpio.h>
+#include <sys/lock.h>
+#include <sys/proc.h>
+
+#include <pci/pcivar.h>
+#include <pci/pcireg.h>
+#include <pci/agppriv.h>
+#include <pci/agpvar.h>
+#include <pci/agpreg.h>
+
+#include <vm/vm.h>
+#include <vm/vm_object.h>
+#include <vm/vm_page.h>
+#include <vm/vm_pageout.h>
+#include <vm/pmap.h>
+
+#include <machine/md_var.h>
+#include <machine/bus.h>
+#include <machine/resource.h>
+#include <sys/rman.h>
+
+MODULE_VERSION(agp, 1);
+
+MALLOC_DEFINE(M_AGP, "agp", "AGP data structures");
+
+#define CDEV_MAJOR	148
+				/* agp_drv.c */
+static d_open_t agp_open;
+static d_close_t agp_close;
+static d_ioctl_t agp_ioctl;
+static d_mmap_t agp_mmap;
+
+static struct cdevsw agp_cdevsw = {
+	/* open */	agp_open,
+	/* close */	agp_close,
+	/* read */	noread,
+	/* write */	nowrite,
+	/* ioctl */	agp_ioctl,
+	/* poll */	nopoll,
+	/* mmap */	agp_mmap,
+	/* strategy */	nostrategy,
+	/* name */	"agp",
+	/* maj */	CDEV_MAJOR,
+	/* dump */	nodump,
+	/* psize */	nopsize,
+	/* flags */	D_TTY,
+	/* bmaj */	-1
+};
+
+static devclass_t agp_devclass;
+#define KDEV2DEV(kdev)	devclass_get_device(agp_devclass, minor(kdev))
+
+/* Helper functions for implementing chipset mini drivers. */
+
+#ifdef __i386__
+#define agp_flush_cache()	wbinvd()
+#endif
+
+u_int8_t
+agp_find_caps(device_t dev)
+{
+	u_int32_t status;
+	u_int8_t ptr, next;
+
+	/*
+	 * Check the CAP_LIST bit of the PCI status register first.
+	 */
+	status = pci_read_config(dev, PCIR_STATUS, 2);
+	if (!(status & 0x10))
+		return 0;
+
+	/*
+	 * Traverse the capabilities list.
+	 */
+	for (ptr = pci_read_config(dev, AGP_CAPPTR, 1);
+	     ptr != 0;
+	     ptr = next) {
+		u_int32_t capid = pci_read_config(dev, ptr, 4);
+		next = AGP_CAPID_GET_NEXT_PTR(capid);
+
+		/*
+		 * If this capability entry ID is 2, then we are done.
+		 */
+		if (AGP_CAPID_GET_CAP_ID(capid) == 2)
+			return ptr;
+	}
+
+	return 0;
+}
+
+/*
+ * Find an AGP display device (if any).
+ */
+static device_t
+agp_find_display(void)
+{
+	devclass_t pci = devclass_find("pci");
+	device_t bus, dev = 0;
+	device_t *kids;
+	int busnum, numkids, i;
+
+	for (busnum = 0; busnum < devclass_get_maxunit(pci); busnum++) {
+		bus = devclass_get_device(pci, busnum);
+		if (!bus)
+			continue;
+		device_get_children(bus, &kids, &numkids);
+		for (i = 0; i < numkids; i++) {
+			dev = kids[i];
+			if (pci_get_class(dev) == PCIC_DISPLAY
+			    && pci_get_subclass(dev) == PCIS_DISPLAY_VGA)
+				if (agp_find_caps(dev)) {
+					free(kids, M_TEMP);
+					return dev;
+				}
+					
+		}
+		free(kids, M_TEMP);
+	}
+
+	return 0;
+}
+
+struct agp_gatt *
+agp_alloc_gatt(device_t dev)
+{
+	u_int32_t apsize = AGP_GET_APERTURE(dev);
+	u_int32_t entries = apsize >> AGP_PAGE_SHIFT;
+	struct agp_gatt *gatt;
+
+	if (bootverbose)
+		device_printf(dev,
+			      "allocating GATT for aperture of size %dM\n",
+			      apsize / (1024*1024));
+
+	gatt = malloc(sizeof(struct agp_gatt), M_AGP, M_NOWAIT);
+	if (!gatt)
+		return 0;
+
+	gatt->ag_entries = entries;
+	gatt->ag_virtual = contigmalloc(entries * sizeof(u_int32_t), M_AGP, 0,
+					0, ~0, PAGE_SIZE, 0);
+	if (!gatt->ag_virtual) {
+		if (bootverbose)
+			device_printf(dev, "contiguous allocation failed\n");
+		free(gatt, M_AGP);
+		return 0;
+	}
+	bzero(gatt->ag_virtual, entries * sizeof(u_int32_t));
+	gatt->ag_physical = vtophys((vm_offset_t) gatt->ag_virtual);
+	agp_flush_cache();
+
+	return gatt;
+}
+
+void
+agp_free_gatt(struct agp_gatt *gatt)
+{
+	contigfree(gatt->ag_virtual,
+		   gatt->ag_entries * sizeof(u_int32_t), M_AGP);
+	free(gatt, M_AGP);
+}
+
+static int agp_max[][2] = {
+	{0,	0},
+	{32,	4},
+	{64,	28},
+	{128,	96},
+	{256,	204},
+	{512,	440},
+	{1024,	942},
+	{2048,	1920},
+	{4096,	3932}
+};
+#define agp_max_size	(sizeof(agp_max) / sizeof(agp_max[0]))
+
+int
+agp_generic_attach(device_t dev)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+	int rid, memsize, i;
+
+	/*
+	 * Find and map the aperture.
+	 */
+	rid = AGP_APBASE;
+	sc->as_aperture = bus_alloc_resource(dev, SYS_RES_MEMORY, &rid,
+					     0, ~0, 1, RF_ACTIVE);
+	if (!sc->as_aperture)
+		return ENOMEM;
+
+	/*
+	 * Work out an upper bound for agp memory allocation. This
+	 * uses a heurisitc table from the Linux driver.
+	 */
+	memsize = ptoa(Maxmem) >> 20;
+	for (i = 0; i < agp_max_size; i++) {
+		if (memsize <= agp_max[i][0])
+			break;
+	}
+	if (i == agp_max_size) i = agp_max_size - 1;
+	sc->as_maxmem = agp_max[i][1] << 20U;
+
+	/*
+	 * The lock is used to prevent re-entry to
+	 * agp_generic_bind_memory() since that function can sleep.
+	 */
+	lockinit(&sc->as_lock, PZERO|PCATCH, "agplk", 0, 0);
+
+	/*
+	 * Initialise stuff for the userland device.
+	 */
+	agp_devclass = devclass_find("agp");
+	TAILQ_INIT(&sc->as_memory);
+	sc->as_nextid = 1;
+
+	sc->as_devnode = make_dev(&agp_cdevsw,
+				  device_get_unit(dev),
+				  UID_ROOT,
+				  GID_WHEEL,
+				  0600,
+				  "agpgart");
+
+	return 0;
+}
+
+int
+agp_generic_detach(device_t dev)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+	bus_release_resource(dev, SYS_RES_MEMORY, AGP_APBASE, sc->as_aperture);
+	lockmgr(&sc->as_lock, LK_DRAIN, 0, curproc);
+	destroy_dev(sc->as_devnode);
+	agp_flush_cache();
+	return 0;
+}
+
+int
+agp_generic_enable(device_t dev, u_int32_t mode)
+{
+	device_t mdev = agp_find_display();
+	u_int32_t tstatus, mstatus;
+	u_int32_t command;
+	int rq, sba, fw, rate;;
+
+	if (!mdev) {
+		AGP_DPF("can't find display\n");
+		return ENXIO;
+	}
+
+	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
+	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
+
+	/* Set RQ to the min of mode, tstatus and mstatus */
+	rq = AGP_MODE_GET_RQ(mode);
+	if (AGP_MODE_GET_RQ(tstatus) < rq)
+		rq = AGP_MODE_GET_RQ(tstatus);
+	if (AGP_MODE_GET_RQ(mstatus) < rq)
+		rq = AGP_MODE_GET_RQ(mstatus);
+
+	/* Set SBA if all three can deal with SBA */
+	sba = (AGP_MODE_GET_SBA(tstatus)
+	       & AGP_MODE_GET_SBA(mstatus)
+	       & AGP_MODE_GET_SBA(mode));
+
+	/* Similar for FW */
+	fw = (AGP_MODE_GET_FW(tstatus)
+	       & AGP_MODE_GET_FW(mstatus)
+	       & AGP_MODE_GET_FW(mode));
+
+	/* Figure out the max rate */
+	rate = (AGP_MODE_GET_RATE(tstatus)
+		& AGP_MODE_GET_RATE(mstatus)
+		& AGP_MODE_GET_RATE(mode));
+	if (rate & AGP_MODE_RATE_4x)
+		rate = AGP_MODE_RATE_4x;
+	else if (rate & AGP_MODE_RATE_2x)
+		rate = AGP_MODE_RATE_2x;
+	else
+		rate = AGP_MODE_RATE_1x;
+
+	/* Construct the new mode word and tell the hardware */
+	command = AGP_MODE_SET_RQ(0, rq);
+	command = AGP_MODE_SET_SBA(command, sba);
+	command = AGP_MODE_SET_FW(command, fw);
+	command = AGP_MODE_SET_RATE(command, rate);
+	command = AGP_MODE_SET_AGP(command, 1);
+	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
+	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
+
+	return 0;
+}
+
+struct agp_memory *
+agp_generic_alloc_memory(device_t dev, int type, vm_size_t size)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+	struct agp_memory *mem;
+
+	if ((size & (AGP_PAGE_SIZE - 1)) != 0)
+		return 0;
+
+	if (sc->as_allocated + size > sc->as_maxmem)
+		return 0;
+
+	mem = malloc(sizeof *mem, M_AGP, M_WAITOK);
+	mem->am_id = sc->as_nextid++;
+	mem->am_size = size;
+	mem->am_obj = vm_object_allocate(OBJT_DEFAULT, atop(round_page(size)));
+	mem->am_physical = 0;
+	mem->am_offset = 0;
+	mem->am_is_bound = 0;
+	TAILQ_INSERT_TAIL(&sc->as_memory, mem, am_link);
+	sc->as_allocated += size;
+
+	return mem;
+}
+
+int
+agp_generic_free_memory(device_t dev, struct agp_memory *mem)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+
+	if (mem->am_is_bound)
+		return EBUSY;
+
+	sc->as_allocated -= mem->am_size;
+	TAILQ_REMOVE(&sc->as_memory, mem, am_link);
+	vm_object_deallocate(mem->am_obj);
+	free(mem, M_AGP);
+	return 0;
+}
+
+int
+agp_generic_bind_memory(device_t dev, struct agp_memory *mem,
+			vm_offset_t offset)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+	vm_offset_t i, j, k;
+	vm_page_t m;
+	int error;
+
+	lockmgr(&sc->as_lock, LK_EXCLUSIVE, 0, curproc);
+
+	if (mem->am_is_bound) {
+		device_printf(dev, "memory already bound\n");
+		return EINVAL;
+	}
+	
+	if (offset < 0
+	    || (offset & (AGP_PAGE_SIZE - 1)) != 0
+	    || offset + mem->am_size > AGP_GET_APERTURE(dev)) {
+		device_printf(dev, "binding memory at bad offset %#x\n",
+			      (int) offset);
+		return EINVAL;
+	}
+
+	/*
+	 * Bind the individual pages and flush the chipset's
+	 * TLB.
+	 *
+	 * XXX Presumably, this needs to be the pci address on alpha
+	 * (i.e. use alpha_XXX_dmamap()). I don't have access to any
+	 * alpha AGP hardware to check.
+	 */
+	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
+		/*
+		 * Find a page from the object and wire it
+		 * down. This page will be mapped using one or more
+		 * entries in the GATT (assuming that PAGE_SIZE >=
+		 * AGP_PAGE_SIZE. If this is the first call to bind,
+		 * the pages will be allocated and zeroed.
+		 */
+		m = vm_page_grab(mem->am_obj, OFF_TO_IDX(i),
+				 VM_ALLOC_ZERO | VM_ALLOC_RETRY);
+		AGP_DPF("found page pa=%#x\n", VM_PAGE_TO_PHYS(m));
+		vm_page_wire(m);
+
+		/*
+		 * Install entries in the GATT, making sure that if
+		 * AGP_PAGE_SIZE < PAGE_SIZE and mem->am_size is not
+		 * aligned to PAGE_SIZE, we don't modify too many GATT 
+		 * entries.
+		 */
+		for (j = 0; j < PAGE_SIZE && i + j < mem->am_size;
+		     j += AGP_PAGE_SIZE) {
+			vm_offset_t pa = VM_PAGE_TO_PHYS(m) + j;
+			AGP_DPF("binding offset %#x to pa %#x\n",
+				offset + i + j, pa);
+			error = AGP_BIND_PAGE(dev, offset + i + j, pa);
+			if (error) {
+				/*
+				 * Bail out. Reverse all the mappings
+				 * and unwire the pages.
+				 */
+				vm_page_wakeup(m);
+				for (k = 0; k < i + j; k += AGP_PAGE_SIZE)
+					AGP_UNBIND_PAGE(dev, offset + k);
+				for (k = 0; k <= i; k += PAGE_SIZE) {
+					m = vm_page_lookup(mem->am_obj,
+							   OFF_TO_IDX(k));
+					vm_page_unwire(m, 0);
+				}
+				lockmgr(&sc->as_lock, LK_RELEASE, 0, curproc);
+				return error;
+			}
+		}
+		vm_page_wakeup(m);
+	}
+
+	/*
+	 * Flush the cpu cache since we are providing a new mapping
+	 * for these pages.
+	 */
+	agp_flush_cache();
+
+	/*
+	 * Make sure the chipset gets the new mappings.
+	 */
+	AGP_FLUSH_TLB(dev);
+
+	mem->am_offset = offset;
+	mem->am_is_bound = 1;
+
+	lockmgr(&sc->as_lock, LK_RELEASE, 0, curproc);
+
+	return 0;
+}
+
+int
+agp_generic_unbind_memory(device_t dev, struct agp_memory *mem)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+	vm_page_t m;
+	int i;
+
+	lockmgr(&sc->as_lock, LK_EXCLUSIVE, 0, curproc);
+
+	if (!mem->am_is_bound) {
+		device_printf(dev, "memory is not bound\n");
+		return EINVAL;
+	}
+
+
+	/*
+	 * Unbind the individual pages and flush the chipset's
+	 * TLB. Unwire the pages so they can be swapped.
+	 */
+	for (i = 0; i < mem->am_size; i += AGP_PAGE_SIZE)
+		AGP_UNBIND_PAGE(dev, mem->am_offset + i);
+	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
+		m = vm_page_lookup(mem->am_obj, atop(i));
+		vm_page_unwire(m, 0);
+	}
+		
+	agp_flush_cache();
+	AGP_FLUSH_TLB(dev);
+
+	mem->am_offset = 0;
+	mem->am_is_bound = 0;
+
+	lockmgr(&sc->as_lock, LK_RELEASE, 0, curproc);
+
+	return 0;
+}
+
+/* Helper functions for implementing user/kernel api */
+
+static int
+agp_acquire_helper(device_t dev, enum agp_acquire_state state)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+
+	if (sc->as_state != AGP_ACQUIRE_FREE)
+		return EBUSY;
+	sc->as_state = state;
+
+	return 0;
+}
+
+static int
+agp_release_helper(device_t dev, enum agp_acquire_state state)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+	struct agp_memory *mem;
+
+	if (sc->as_state == AGP_ACQUIRE_FREE)
+		return 0;
+
+	if (sc->as_state != state)
+		return EBUSY;
+
+	/*
+	 * Clear out the aperture and free any outstanding memory blocks.
+	 */
+	while ((mem = TAILQ_FIRST(&sc->as_memory)) != 0) {
+		if (mem->am_is_bound)
+			AGP_UNBIND_MEMORY(dev, mem);
+		AGP_FREE_MEMORY(dev, mem);
+	}
+
+	sc->as_state = AGP_ACQUIRE_FREE;
+	return 0;
+}
+
+static struct agp_memory *
+agp_find_memory(device_t dev, int id)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+	struct agp_memory *mem;
+
+	AGP_DPF("searching for memory block %d\n", id);
+	TAILQ_FOREACH(mem, &sc->as_memory, am_link) {
+		AGP_DPF("considering memory block %d\n", mem->am_id);
+		if (mem->am_id == id)
+			return mem;
+	}
+	return 0;
+}
+
+/* Implementation of the userland ioctl api */
+
+static int
+agp_info_user(device_t dev, agp_info *info)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+
+	bzero(info, sizeof *info);
+	info->bridge_id = pci_get_devid(dev);
+	info->agp_mode = 
+	    pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
+	info->aper_base = rman_get_start(sc->as_aperture);
+	info->aper_size = AGP_GET_APERTURE(dev) >> 20;
+	info->pg_total = info->pg_system = sc->as_maxmem >> AGP_PAGE_SHIFT;
+	info->pg_used = sc->as_allocated >> AGP_PAGE_SHIFT;
+
+	return 0;
+}
+
+static int
+agp_setup_user(device_t dev, agp_setup *setup)
+{
+	return AGP_ENABLE(dev, setup->agp_mode);
+}
+
+static int
+agp_allocate_user(device_t dev, agp_allocate *alloc)
+{
+	struct agp_memory *mem;
+
+	mem = AGP_ALLOC_MEMORY(dev,
+			       alloc->type,
+			       alloc->pg_count << AGP_PAGE_SHIFT);
+	alloc->key = mem->am_id;
+	alloc->physical = mem->am_physical;
+
+	return 0;
+}
+
+static int
+agp_deallocate_user(device_t dev, int id)
+{
+	struct agp_memory *mem = agp_find_memory(dev, id);;
+
+	if (mem) {
+		AGP_FREE_MEMORY(dev, mem);
+		return 0;
+	} else {
+		return ENOENT;
+	}
+}
+
+static int
+agp_bind_user(device_t dev, agp_bind *bind)
+{
+	struct agp_memory *mem = agp_find_memory(dev, bind->key);
+
+	if (!mem)
+		return ENOENT;
+
+	return AGP_BIND_MEMORY(dev, mem, bind->pg_start << AGP_PAGE_SHIFT);
+}
+
+static int
+agp_unbind_user(device_t dev, agp_unbind *unbind)
+{
+	struct agp_memory *mem = agp_find_memory(dev, unbind->key);
+
+	if (!mem)
+		return ENOENT;
+
+	return AGP_UNBIND_MEMORY(dev, mem);
+}
+
+static int
+agp_open(dev_t kdev, int oflags, int devtype, struct proc *p)
+{
+	device_t dev = KDEV2DEV(kdev);
+	struct agp_softc *sc = device_get_softc(dev);
+
+	if (!sc->as_isopen) {
+		sc->as_isopen = 1;
+		device_busy(dev);
+	}
+
+	return 0;
+}
+
+static int
+agp_close(dev_t kdev, int fflag, int devtype, struct proc *p)
+{
+	device_t dev = KDEV2DEV(kdev);
+	struct agp_softc *sc = device_get_softc(dev);
+
+	/*
+	 * Clear the GATT and force release on last close
+	 */
+	if (sc->as_state == AGP_ACQUIRE_USER)
+		agp_release_helper(dev, AGP_ACQUIRE_USER);
+	sc->as_isopen = 0;
+	device_unbusy(dev);
+
+	return 0;
+}
+
+static int
+agp_ioctl(dev_t kdev, u_long cmd, caddr_t data, int fflag, struct proc *p)
+{
+	device_t dev = KDEV2DEV(kdev);
+
+	switch (cmd) {
+	case AGPIOC_INFO:
+		return agp_info_user(dev, (agp_info *) data);
+
+	case AGPIOC_ACQUIRE:
+		return agp_acquire_helper(dev, AGP_ACQUIRE_USER);
+
+	case AGPIOC_RELEASE:
+		return agp_release_helper(dev, AGP_ACQUIRE_USER);
+
+	case AGPIOC_SETUP:
+		return agp_setup_user(dev, (agp_setup *)data);
+
+	case AGPIOC_ALLOCATE:
+		return agp_allocate_user(dev, (agp_allocate *)data);
+
+	case AGPIOC_DEALLOCATE:
+		return agp_deallocate_user(dev, *(int *) data);
+
+	case AGPIOC_BIND:
+		return agp_bind_user(dev, (agp_bind *)data);
+
+	case AGPIOC_UNBIND:
+		return agp_unbind_user(dev, (agp_unbind *)data);
+
+	}
+
+	return EINVAL;
+}
+
+static int
+agp_mmap(dev_t kdev, vm_offset_t offset, int prot)
+{
+	device_t dev = KDEV2DEV(kdev);
+	struct agp_softc *sc = device_get_softc(dev);
+
+	if (offset > AGP_GET_APERTURE(dev))
+		return -1;
+	return atop(rman_get_start(sc->as_aperture) + offset);
+}
+
+/* Implementation of the kernel api */
+
+device_t
+agp_find_device()
+{
+	if (!agp_devclass)
+		return 0;
+	return devclass_get_device(agp_devclass, 0);
+}
+
+enum agp_acquire_state
+agp_state(device_t dev)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+	return sc->as_state;
+}
+
+void
+agp_get_info(device_t dev, struct agp_info *info)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+
+	info->ai_mode =
+		pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
+	info->ai_aperture_base = rman_get_start(sc->as_aperture);
+	info->ai_aperture_size = (rman_get_end(sc->as_aperture)
+				  - rman_get_start(sc->as_aperture)) + 1;
+	info->ai_memory_allowed = sc->as_maxmem;
+	info->ai_memory_used = sc->as_allocated;
+}
+
+int
+agp_acquire(device_t dev)
+{
+	return agp_acquire_helper(dev, AGP_ACQUIRE_KERNEL);
+}
+
+int
+agp_release(device_t dev)
+{
+	return agp_release_helper(dev, AGP_ACQUIRE_KERNEL);
+}
+
+int
+agp_enable(device_t dev, u_int32_t mode)
+{
+	return AGP_ENABLE(dev, mode);
+}
+
+void *agp_alloc_memory(device_t dev, int type, vm_size_t bytes)
+{
+	return  (void *) AGP_ALLOC_MEMORY(dev, type, bytes);
+}
+
+void agp_free_memory(device_t dev, void *handle)
+{
+	struct agp_memory *mem = (struct agp_memory *) handle;
+	AGP_FREE_MEMORY(dev, mem);
+}
+
+int agp_bind_memory(device_t dev, void *handle, vm_offset_t offset)
+{
+	struct agp_memory *mem = (struct agp_memory *) handle;
+	return AGP_BIND_MEMORY(dev, mem, offset);
+}
+
+int agp_unbind_memory(device_t dev, void *handle)
+{
+	struct agp_memory *mem = (struct agp_memory *) handle;
+	return AGP_UNBIND_MEMORY(dev, mem);
+}
+
+void agp_memory_info(device_t dev, void *handle, struct
+		     agp_memory_info *mi)
+{
+	struct agp_memory *mem = (struct agp_memory *) handle;
+
+	mi->ami_size = mem->am_size;
+	mi->ami_physical = mem->am_physical;
+	mi->ami_offset = mem->am_offset;
+	mi->ami_is_bound = mem->am_is_bound;
+}
diff --git a/sys/dev/agp/agp_ali.c b/sys/dev/agp/agp_ali.c
new file mode 100644
index 0000000..86e070e
--- /dev/null
+++ b/sys/dev/agp/agp_ali.c
@@ -0,0 +1,264 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#include "opt_bus.h"
+#include "opt_pci.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/kernel.h>
+#include <sys/bus.h>
+#include <sys/lock.h>
+
+#include <pci/pcivar.h>
+#include <pci/pcireg.h>
+#include <pci/agppriv.h>
+#include <pci/agpreg.h>
+
+#include <vm/vm.h>
+#include <vm/vm_object.h>
+#include <vm/pmap.h>
+
+struct agp_ali_softc {
+	struct agp_softc agp;
+	u_int32_t	initial_aperture; /* aperture size at startup */
+	struct agp_gatt *gatt;
+};
+
+static const char*
+agp_ali_match(device_t dev)
+{
+	if (pci_get_class(dev) != PCIC_BRIDGE
+	    || pci_get_subclass(dev) != PCIS_BRIDGE_HOST)
+		return NULL;
+
+	if (agp_find_caps(dev) == 0)
+		return NULL;
+
+	switch (pci_get_devid(dev)) {
+	case 0x154110b9:
+		return ("Ali M1541 host to AGP bridge");
+	};
+
+	if (pci_get_vendor(dev) == 0x10b9)
+		return ("Ali Generic host to PCI bridge");
+
+	return NULL;
+}
+
+static int
+agp_ali_probe(device_t dev)
+{
+	const char *desc;
+
+	desc = agp_ali_match(dev);
+	if (desc) {
+		device_verbose(dev);
+		device_set_desc(dev, desc);
+		return 0;
+	}
+
+	return ENXIO;
+}
+
+static int
+agp_ali_attach(device_t dev)
+{
+	struct agp_ali_softc *sc = device_get_softc(dev);
+	struct agp_gatt *gatt;
+	int error;
+
+	error = agp_generic_attach(dev);
+	if (error)
+		return error;
+
+	sc->initial_aperture = AGP_GET_APERTURE(dev);
+
+	for (;;) {
+		gatt = agp_alloc_gatt(dev);
+		if (gatt)
+			break;
+
+		/*
+		 * Probably contigmalloc failure. Try reducing the
+		 * aperture so that the gatt size reduces.
+		 */
+		if (AGP_SET_APERTURE(dev, AGP_GET_APERTURE(dev) / 2)) {
+			agp_generic_detach(dev);
+			return ENOMEM;
+		}
+	}
+	sc->gatt = gatt;
+
+	/* Install the gatt. */
+	pci_write_config(dev, AGP_ALI_ATTBASE,
+			 (gatt->ag_physical
+			  | (pci_read_config(dev, AGP_ALI_ATTBASE, 4) & 0xff)),
+			 4);
+	
+	/* Enable the TLB. */
+	pci_write_config(dev, AGP_ALI_TLBCTRL, 0x10, 1);
+
+	return 0;
+}
+
+static int
+agp_ali_detach(device_t dev)
+{
+	struct agp_ali_softc *sc = device_get_softc(dev);
+	int error;
+
+	error = agp_generic_detach(dev);
+	if (error)
+		return error;
+
+	/* Disable the TLB.. */
+	pci_write_config(dev, AGP_ALI_TLBCTRL, 0x90, 1);
+
+	/* Put the aperture back the way it started. */
+	AGP_SET_APERTURE(dev, sc->initial_aperture);
+	pci_write_config(dev, AGP_ALI_ATTBASE,
+			 pci_read_config(dev, AGP_ALI_ATTBASE, 4) & 0xff,
+			 4);
+
+	agp_free_gatt(sc->gatt);
+	return 0;
+}
+
+#define M 1024*1024
+
+static u_int32_t agp_ali_table[] = {
+	0,			/* 0 - invalid */
+	1,			/* 1 - invalid */
+	2,			/* 2 - invalid */
+	4*M,			/* 3 - invalid */
+	8*M,			/* 4 - invalid */
+	0,			/* 5 - invalid */
+	16*M,			/* 6 - invalid */
+	32*M,			/* 7 - invalid */
+	64*M,			/* 8 - invalid */
+	128*M,			/* 9 - invalid */
+	256*M,			/* 10 - invalid */
+};
+#define agp_ali_table_size (sizeof(agp_ali_table) / sizeof(agp_ali_table[0]))
+
+static u_int32_t
+agp_ali_get_aperture(device_t dev)
+{
+	/*
+	 * The aperture size is derived from the low bits of attbase.
+	 * I'm not sure this is correct..
+	 */
+	int i = pci_read_config(dev, AGP_ALI_ATTBASE, 4) & 0xff;
+	if (i >= agp_ali_table_size)
+		return 0;
+	return agp_ali_table[i];
+}
+
+static int
+agp_ali_set_aperture(device_t dev, u_int32_t aperture)
+{
+	int i;
+
+	for (i = 0; i < agp_ali_table_size; i++)
+		if (agp_ali_table[i] == aperture)
+			break;
+	if (i == agp_ali_table_size)
+		return EINVAL;
+
+	pci_write_config(dev, AGP_ALI_ATTBASE,
+			 ((pci_read_config(dev, AGP_ALI_ATTBASE, 4) & ~0xff)
+			  | i), 4);
+	return 0;
+}
+
+static int
+agp_ali_bind_page(device_t dev, int offset, vm_offset_t physical)
+{
+	struct agp_ali_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = physical;
+	return 0;
+}
+
+static int
+agp_ali_unbind_page(device_t dev, int offset)
+{
+	struct agp_ali_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = 0;
+	return 0;
+}
+
+static void
+agp_ali_flush_tlb(device_t dev)
+{
+	pci_write_config(dev, AGP_ALI_TLBCTRL, 0x90, 1);
+	pci_write_config(dev, AGP_ALI_TLBCTRL, 0x10, 1);
+}
+
+static device_method_t agp_ali_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		agp_ali_probe),
+	DEVMETHOD(device_attach,	agp_ali_attach),
+	DEVMETHOD(device_detach,	agp_ali_detach),
+	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
+	DEVMETHOD(device_suspend,	bus_generic_suspend),
+	DEVMETHOD(device_resume,	bus_generic_resume),
+
+	/* AGP interface */
+	DEVMETHOD(agp_get_aperture,	agp_ali_get_aperture),
+	DEVMETHOD(agp_set_aperture,	agp_ali_set_aperture),
+	DEVMETHOD(agp_bind_page,	agp_ali_bind_page),
+	DEVMETHOD(agp_unbind_page,	agp_ali_unbind_page),
+	DEVMETHOD(agp_flush_tlb,	agp_ali_flush_tlb),
+	DEVMETHOD(agp_enable,		agp_generic_enable),
+	DEVMETHOD(agp_alloc_memory,	agp_generic_alloc_memory),
+	DEVMETHOD(agp_free_memory,	agp_generic_free_memory),
+	DEVMETHOD(agp_bind_memory,	agp_generic_bind_memory),
+	DEVMETHOD(agp_unbind_memory,	agp_generic_unbind_memory),
+
+	{ 0, 0 }
+};
+
+static driver_t agp_ali_driver = {
+	"agp",
+	agp_ali_methods,
+	sizeof(struct agp_ali_softc),
+};
+
+static devclass_t agp_devclass;
+
+DRIVER_MODULE(agp_ali, pci, agp_ali_driver, agp_devclass, 0, 0);
diff --git a/sys/dev/agp/agp_amd.c b/sys/dev/agp/agp_amd.c
new file mode 100644
index 0000000..112918a
--- /dev/null
+++ b/sys/dev/agp/agp_amd.c
@@ -0,0 +1,276 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#include "opt_bus.h"
+#include "opt_pci.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/kernel.h>
+#include <sys/bus.h>
+#include <sys/lock.h>
+
+#include <pci/pcivar.h>
+#include <pci/pcireg.h>
+#include <pci/agppriv.h>
+#include <pci/agpreg.h>
+
+#include <vm/vm.h>
+#include <vm/vm_object.h>
+#include <vm/pmap.h>
+#include <machine/clock.h>
+#include <machine/bus.h>
+#include <machine/resource.h>
+#include <sys/rman.h>
+
+#define READ2(off)	bus_space_read_2(sc->bst, sc->bsh, off)
+#define READ4(off)	bus_space_read_4(sc->bst, sc->bsh, off)
+#define WRITE2(off,v)	bus_space_write_2(sc->bst, sc->bsh, off, v)
+#define WRITE4(off,v)	bus_space_write_4(sc->bst, sc->bsh, off, v)
+
+struct agp_amd_softc {
+	struct agp_softc agp;
+	struct resource *regs;	/* memory mapped control registers */
+	bus_space_tag_t bst;	/* bus_space tag */
+	bus_space_handle_t bsh;	/* bus_space handle */
+	u_int32_t	initial_aperture; /* aperture size at startup */
+	struct agp_gatt *gatt;
+};
+
+static const char*
+agp_amd_match(device_t dev)
+{
+	if (pci_get_class(dev) != PCIC_BRIDGE
+	    || pci_get_subclass(dev) != PCIS_BRIDGE_HOST)
+		return NULL;
+
+	if (agp_find_caps(dev) == 0)
+		return NULL;
+
+	switch (pci_get_devid(dev)) {
+	case 0x70061022:
+		return ("AMD 751 host to AGP bridge");
+	};
+
+	return NULL;
+}
+
+static int
+agp_amd_probe(device_t dev)
+{
+	const char *desc;
+
+	desc = agp_amd_match(dev);
+	if (desc) {
+		device_verbose(dev);
+		device_set_desc(dev, desc);
+		return 0;
+	}
+
+	return ENXIO;
+}
+
+static int
+agp_amd_attach(device_t dev)
+{
+	struct agp_amd_softc *sc = device_get_softc(dev);
+	struct agp_gatt *gatt;
+	int error, rid;
+
+	error = agp_generic_attach(dev);
+	if (error)
+		return error;
+
+	rid = AGP_AMD751_REGISTERS;
+	sc->regs = bus_alloc_resource(dev, SYS_RES_MEMORY, &rid,
+				      0, ~0, 1, RF_ACTIVE);
+	if (!sc->regs) {
+		agp_generic_detach(dev);
+		return ENOMEM;
+	}
+
+	sc->bst = rman_get_bustag(sc->regs);
+	sc->bsh = rman_get_bushandle(sc->regs);
+
+	sc->initial_aperture = AGP_GET_APERTURE(dev);
+
+	for (;;) {
+		gatt = agp_alloc_gatt(dev);
+		if (gatt)
+			break;
+
+		/*
+		 * Probably contigmalloc failure. Try reducing the
+		 * aperture so that the gatt size reduces.
+		 */
+		if (AGP_SET_APERTURE(dev, AGP_GET_APERTURE(dev) / 2))
+			return ENOMEM;
+	}
+	sc->gatt = gatt;
+
+	/* Install the gatt. */
+	WRITE4(AGP_AMD751_ATTBASE, gatt->ag_physical);
+	
+	/* Enable synchronisation between host and agp. */
+	pci_write_config(dev, AGP_AMD751_MODECTRL, 0x80, 1);
+
+	/* Enable the TLB and flush */
+	WRITE2(AGP_AMD751_STATUS,
+	       READ2(AGP_AMD751_STATUS) | AGP_AMD751_STATUS_GCE);
+	AGP_FLUSH_TLB(dev);
+
+	return agp_generic_attach(dev);
+}
+
+static int
+agp_amd_detach(device_t dev)
+{
+	struct agp_amd_softc *sc = device_get_softc(dev);
+
+	/* Disable the TLB.. */
+	WRITE2(AGP_AMD751_STATUS,
+	       READ2(AGP_AMD751_STATUS) & ~AGP_AMD751_STATUS_GCE);
+	
+	/* Disable host-agp sync */
+	pci_write_config(dev, AGP_AMD751_MODECTRL, 0x00, 1);
+	
+	/* Clear the GATT base */
+	WRITE4(AGP_AMD751_ATTBASE, 0);
+
+	/* Put the aperture back the way it started. */
+	AGP_SET_APERTURE(dev, sc->initial_aperture);
+
+	agp_free_gatt(sc->gatt);
+	return 0;
+}
+
+static u_int32_t
+agp_amd_get_aperture(device_t dev)
+{
+	int vas;
+
+	/*
+	 * The aperture size is equal to 32M<<vas.
+	 */
+	vas = (pci_read_config(dev, AGP_AMD751_APCTRL, 1) & 0x06) >> 1;
+	return (32*1024*1024) << vas;
+}
+
+static int
+agp_amd_set_aperture(device_t dev, u_int32_t aperture)
+{
+	int vas;
+
+	/*
+	 * Check for a power of two and make sure its within the
+	 * programmable range.
+	 */
+	if (aperture & (aperture - 1)
+	    || aperture < 32*1024*1024
+	    || aperture > 2U*1024*1024*1024)
+		return EINVAL;
+
+	vas = ffs(aperture / 32*1024*1024) - 1;
+	
+	pci_write_config(dev, AGP_AMD751_APCTRL,
+			 ((pci_read_config(dev, AGP_AMD751_APCTRL, 1) & ~0x06)
+			  | vas << 1), 1);
+
+	return 0;
+}
+
+static int
+agp_amd_bind_page(device_t dev, int offset, vm_offset_t physical)
+{
+	struct agp_amd_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = physical | 1;
+	return 0;
+}
+
+static int
+agp_amd_unbind_page(device_t dev, int offset)
+{
+	struct agp_amd_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = 0;
+	return 0;
+}
+
+static void
+agp_amd_flush_tlb(device_t dev)
+{
+	struct agp_amd_softc *sc = device_get_softc(dev);
+
+	/* Set the cache invalidate bit and wait for the chipset to clear */
+	WRITE4(AGP_AMD751_TLBCTRL, 1);
+	do {
+		DELAY(1);
+	} while (READ4(AGP_AMD751_TLBCTRL));
+}
+
+static device_method_t agp_amd_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		agp_amd_probe),
+	DEVMETHOD(device_attach,	agp_amd_attach),
+	DEVMETHOD(device_detach,	agp_amd_detach),
+	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
+	DEVMETHOD(device_suspend,	bus_generic_suspend),
+	DEVMETHOD(device_resume,	bus_generic_resume),
+
+	/* AGP interface */
+	DEVMETHOD(agp_get_aperture,	agp_amd_get_aperture),
+	DEVMETHOD(agp_set_aperture,	agp_amd_set_aperture),
+	DEVMETHOD(agp_bind_page,	agp_amd_bind_page),
+	DEVMETHOD(agp_unbind_page,	agp_amd_unbind_page),
+	DEVMETHOD(agp_flush_tlb,	agp_amd_flush_tlb),
+	DEVMETHOD(agp_enable,		agp_generic_enable),
+	DEVMETHOD(agp_alloc_memory,	agp_generic_alloc_memory),
+	DEVMETHOD(agp_free_memory,	agp_generic_free_memory),
+	DEVMETHOD(agp_bind_memory,	agp_generic_bind_memory),
+	DEVMETHOD(agp_unbind_memory,	agp_generic_unbind_memory),
+
+	{ 0, 0 }
+};
+
+static driver_t agp_amd_driver = {
+	"agp",
+	agp_amd_methods,
+	sizeof(struct agp_amd_softc),
+};
+
+static devclass_t agp_devclass;
+
+DRIVER_MODULE(agp_amd, pci, agp_amd_driver, agp_devclass, 0, 0);
diff --git a/sys/dev/agp/agp_if.m b/sys/dev/agp/agp_if.m
new file mode 100644
index 0000000..06f64d3
--- /dev/null
+++ b/sys/dev/agp/agp_if.m
@@ -0,0 +1,134 @@
+#
+# Copyright (c) 2000 Doug Rabson
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+#
+# $FreeBSD$
+#
+
+#include <sys/bus.h>
+
+#
+# The AGP interface is used internally to the agp driver to isolate the
+# differences between various AGP chipsets into chipset mini drivers. It
+# should not be used outside the AGP driver. The kernel api for accessing
+# AGP functionality is described in <pci/agpvar,h>
+#
+INTERFACE agp;
+
+#
+# Return the current aperture size.
+#
+METHOD u_int32_t get_aperture {
+	device_t	dev;
+};
+
+#
+# Set the size of the aperture. Return EINVAL on error or 0 on success.
+#
+METHOD int set_aperture {
+	device_t	dev;
+	u_int32_t	aperture;
+};
+
+#
+# Bind a single page in the AGP aperture to a given physical address.
+# The offset is a byte offset within the aperture which must be
+# aligned to an AGP page boundary.
+#
+METHOD int bind_page {
+	device_t	dev;
+	vm_offset_t	offset;
+	vm_offset_t	physical;
+};
+
+#
+# Unbind a single page in the AGP aperture.
+#
+METHOD int unbind_page {
+	device_t	dev;
+	vm_offset_t	offset;
+};
+
+#
+# Flush the GATT TLB. This is used after a call to bind_page to
+# ensure that any mappings cached in the chipset are discarded.
+#
+METHOD void flush_tlb {
+	device_t	dev;
+};
+
+#
+# Enable the agp hardware with the relavent mode. The mode bits are
+# defined in <pci/agpreg.h>
+#
+METHOD int enable {
+	device_t	dev;
+	u_int32_t	mode;
+};
+
+#
+# Allocate memory of a given type. The type is a chipset-specific
+# code which is used by certain integrated agp graphics chips
+# (basically just the i810 for now) to access special features of
+# the chipset. An opaque handle representing the memory region is
+# returned and can be used as an argument to free_memory, bind_memory 
+# and unbind_memory.
+#
+# The size is specified in bytes but must be a multiple of the AGP
+# page size.
+#
+METHOD struct agp_memory * alloc_memory {
+	device_t	dev;
+	int		type;
+	vm_size_t	size;
+};
+
+#
+# Free a memory region previously allocated with alloc_memory. Return
+# EBUSY if the memory is bound.
+#
+METHOD int free_memory {
+	device_t	dev;
+	struct agp_memory *mem;
+};
+
+#
+# Bind a memory region to a specific byte offset within the chipset's
+# AGP aperture. This effectively defines a range of contiguous
+# physical address which alias the (possibly uncontiguous) pages in
+# the memory region.
+#
+METHOD int bind_memory {
+	device_t	dev;
+	struct agp_memory *mem;
+	vm_offset_t	offset;
+};
+
+#
+# Unbind a memory region bound with bind_memory.
+#
+METHOD int unbind_memory {
+	device_t	dev;
+	struct agp_memory *handle;
+};
diff --git a/sys/dev/agp/agp_intel.c b/sys/dev/agp/agp_intel.c
new file mode 100644
index 0000000..88d38ec
--- /dev/null
+++ b/sys/dev/agp/agp_intel.c
@@ -0,0 +1,266 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#include "opt_bus.h"
+#include "opt_pci.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/kernel.h>
+#include <sys/bus.h>
+#include <sys/lock.h>
+
+#include <pci/pcivar.h>
+#include <pci/pcireg.h>
+#include <pci/agppriv.h>
+#include <pci/agpreg.h>
+
+#include <vm/vm.h>
+#include <vm/vm_object.h>
+#include <vm/pmap.h>
+
+struct agp_intel_softc {
+	struct agp_softc agp;
+	u_int32_t	initial_aperture; /* aperture size at startup */
+	struct agp_gatt *gatt;
+};
+
+static const char*
+agp_intel_match(device_t dev)
+{
+	if (pci_get_class(dev) != PCIC_BRIDGE
+	    || pci_get_subclass(dev) != PCIS_BRIDGE_HOST)
+		return NULL;
+
+	if (agp_find_caps(dev) == 0)
+		return NULL;
+
+	switch (pci_get_devid(dev)) {
+	/* Intel -- vendor 0x8086 */
+	case 0x71808086:
+		return ("Intel 82443LX (440 LX) host to PCI bridge");
+
+	case 0x71908086:
+		return ("Intel 82443BX (440 BX) host to PCI bridge");
+
+ 	case 0x71a08086:
+ 		return ("Intel 82443GX host to PCI bridge");
+
+ 	case 0x71a18086:
+ 		return ("Intel 82443GX host to AGP bridge");
+	};
+
+	if (pci_get_vendor(dev) == 0x8086)
+		return ("Intel Generic host to PCI bridge");
+
+	return NULL;
+}
+
+static int
+agp_intel_probe(device_t dev)
+{
+	const char *desc;
+
+	desc = agp_intel_match(dev);
+	if (desc) {
+		device_verbose(dev);
+		device_set_desc(dev, desc);
+		return 0;
+	}
+
+	return ENXIO;
+}
+
+static int
+agp_intel_attach(device_t dev)
+{
+	struct agp_intel_softc *sc = device_get_softc(dev);
+	struct agp_gatt *gatt;
+	int error;
+
+	error = agp_generic_attach(dev);
+	if (error)
+		return error;
+
+	sc->initial_aperture = AGP_GET_APERTURE(dev);
+
+	for (;;) {
+		gatt = agp_alloc_gatt(dev);
+		if (gatt)
+			break;
+
+		/*
+		 * Probably contigmalloc failure. Try reducing the
+		 * aperture so that the gatt size reduces.
+		 */
+		if (AGP_SET_APERTURE(dev, AGP_GET_APERTURE(dev) / 2)) {
+			agp_generic_detach(dev);
+			return ENOMEM;
+		}
+	}
+	sc->gatt = gatt;
+
+	/* Install the gatt. */
+	pci_write_config(dev, AGP_INTEL_ATTBASE, gatt->ag_physical, 4);
+	
+	/* Enable things, clear errors etc. */
+	pci_write_config(dev, AGP_INTEL_AGPCTRL, 0x2280, 4);
+	pci_write_config(dev, AGP_INTEL_NBXCFG,
+			 (pci_read_config(dev, AGP_INTEL_NBXCFG, 4)
+			  & ~(1 << 10)) | (1 << 9), 4);
+	pci_write_config(dev, AGP_INTEL_ERRSTS + 1, 7, 1);
+
+	return 0;
+}
+
+static int
+agp_intel_detach(device_t dev)
+{
+	struct agp_intel_softc *sc = device_get_softc(dev);
+	int error;
+
+	error = agp_generic_detach(dev);
+	if (error)
+		return error;
+
+	printf("%s: set NBXCFG to %x\n", __FUNCTION__,
+			 (pci_read_config(dev, AGP_INTEL_NBXCFG, 4)
+			  & ~(1 << 9)));
+	pci_write_config(dev, AGP_INTEL_NBXCFG,
+			 (pci_read_config(dev, AGP_INTEL_NBXCFG, 4)
+			  & ~(1 << 9)), 4);
+	pci_write_config(dev, AGP_INTEL_ATTBASE, 0, 4);
+	AGP_SET_APERTURE(dev, sc->initial_aperture);
+	agp_free_gatt(sc->gatt);
+
+	return 0;
+}
+
+static u_int32_t
+agp_intel_get_aperture(device_t dev)
+{
+	u_int32_t apsize;
+
+	apsize = pci_read_config(dev, AGP_INTEL_APSIZE, 1) & 0x1f;
+
+	/*
+	 * The size is determined by the number of low bits of
+	 * register APBASE which are forced to zero. The low 22 bits
+	 * are always forced to zero and each zero bit in the apsize
+	 * field just read forces the corresponding bit in the 27:22
+	 * to be zero. We calculate the aperture size accordingly.
+	 */
+	return (((apsize ^ 0x1f) << 22) | ((1 << 22) - 1)) + 1;
+}
+
+static int
+agp_intel_set_aperture(device_t dev, u_int32_t aperture)
+{
+	u_int32_t apsize;
+
+	/*
+	 * Reverse the magic from get_aperture.
+	 */
+	apsize = ((aperture - 1) >> 22) ^ 0x1f;
+
+	/*
+	 * Double check for sanity.
+	 */
+	if ((((apsize ^ 0x1f) << 22) | ((1 << 22) - 1)) + 1 != aperture)
+		return EINVAL;
+
+	pci_write_config(dev, AGP_INTEL_APSIZE, apsize, 1);
+
+	return 0;
+}
+
+static int
+agp_intel_bind_page(device_t dev, int offset, vm_offset_t physical)
+{
+	struct agp_intel_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = physical | 0x17;
+	return 0;
+}
+
+static int
+agp_intel_unbind_page(device_t dev, int offset)
+{
+	struct agp_intel_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = 0;
+	return 0;
+}
+
+static void
+agp_intel_flush_tlb(device_t dev)
+{
+	pci_write_config(dev, AGP_INTEL_AGPCTRL, 0x2200, 4);
+	pci_write_config(dev, AGP_INTEL_AGPCTRL, 0x2280, 4);
+}
+
+static device_method_t agp_intel_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		agp_intel_probe),
+	DEVMETHOD(device_attach,	agp_intel_attach),
+	DEVMETHOD(device_detach,	agp_intel_detach),
+	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
+	DEVMETHOD(device_suspend,	bus_generic_suspend),
+	DEVMETHOD(device_resume,	bus_generic_resume),
+
+	/* AGP interface */
+	DEVMETHOD(agp_get_aperture,	agp_intel_get_aperture),
+	DEVMETHOD(agp_set_aperture,	agp_intel_set_aperture),
+	DEVMETHOD(agp_bind_page,	agp_intel_bind_page),
+	DEVMETHOD(agp_unbind_page,	agp_intel_unbind_page),
+	DEVMETHOD(agp_flush_tlb,	agp_intel_flush_tlb),
+	DEVMETHOD(agp_enable,		agp_generic_enable),
+	DEVMETHOD(agp_alloc_memory,	agp_generic_alloc_memory),
+	DEVMETHOD(agp_free_memory,	agp_generic_free_memory),
+	DEVMETHOD(agp_bind_memory,	agp_generic_bind_memory),
+	DEVMETHOD(agp_unbind_memory,	agp_generic_unbind_memory),
+
+	{ 0, 0 }
+};
+
+static driver_t agp_intel_driver = {
+	"agp",
+	agp_intel_methods,
+	sizeof(struct agp_intel_softc),
+};
+
+static devclass_t agp_devclass;
+
+DRIVER_MODULE(agp_intel, pci, agp_intel_driver, agp_devclass, 0, 0);
diff --git a/sys/dev/agp/agp_sis.c b/sys/dev/agp/agp_sis.c
new file mode 100644
index 0000000..1f1a50b
--- /dev/null
+++ b/sys/dev/agp/agp_sis.c
@@ -0,0 +1,256 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#include "opt_bus.h"
+#include "opt_pci.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/kernel.h>
+#include <sys/bus.h>
+#include <sys/lock.h>
+
+#include <pci/pcivar.h>
+#include <pci/pcireg.h>
+#include <pci/agppriv.h>
+#include <pci/agpreg.h>
+
+#include <vm/vm.h>
+#include <vm/vm_object.h>
+#include <vm/pmap.h>
+
+struct agp_sis_softc {
+	struct agp_softc agp;
+	u_int32_t	initial_aperture; /* aperture size at startup */
+	struct agp_gatt *gatt;
+};
+
+static const char*
+agp_sis_match(device_t dev)
+{
+	if (pci_get_class(dev) != PCIC_BRIDGE
+	    || pci_get_subclass(dev) != PCIS_BRIDGE_HOST)
+		return NULL;
+
+	if (agp_find_caps(dev) == 0)
+		return NULL;
+
+	switch (pci_get_devid(dev)) {
+	case 0x00011039:
+		return ("SiS 5591 host to AGP bridge");
+	};
+
+	if (pci_get_vendor(dev) == 0x1039)
+		return ("SIS Generic host to PCI bridge");
+
+	return NULL;
+}
+
+static int
+agp_sis_probe(device_t dev)
+{
+	const char *desc;
+
+	desc = agp_sis_match(dev);
+	if (desc) {
+		device_verbose(dev);
+		device_set_desc(dev, desc);
+		return 0;
+	}
+
+	return ENXIO;
+}
+
+static int
+agp_sis_attach(device_t dev)
+{
+	struct agp_sis_softc *sc = device_get_softc(dev);
+	struct agp_gatt *gatt;
+	int error;
+
+	error = agp_generic_attach(dev);
+	if (error)
+		return error;
+
+	sc->initial_aperture = AGP_GET_APERTURE(dev);
+
+	for (;;) {
+		gatt = agp_alloc_gatt(dev);
+		if (gatt)
+			break;
+
+		/*
+		 * Probably contigmalloc failure. Try reducing the
+		 * aperture so that the gatt size reduces.
+		 */
+		if (AGP_SET_APERTURE(dev, AGP_GET_APERTURE(dev) / 2)) {
+			agp_generic_detach(dev);
+			return ENOMEM;
+		}
+	}
+	sc->gatt = gatt;
+
+	/* Install the gatt. */
+	pci_write_config(dev, AGP_SIS_ATTBASE, gatt->ag_physical, 4);
+	
+	/* Enable the aperture. */
+	pci_write_config(dev, AGP_SIS_WINCTRL,
+			 pci_read_config(dev, AGP_SIS_WINCTRL, 1) | 3, 1);
+
+	/*
+	 * Enable the TLB and make it automatically invalidate entries
+	 * when the GATT is written.
+	 */
+	pci_write_config(dev, AGP_SIS_TLBCTRL, 0x05, 1);
+
+	return 0;
+}
+
+static int
+agp_sis_detach(device_t dev)
+{
+	struct agp_sis_softc *sc = device_get_softc(dev);
+	int error;
+
+	error = agp_generic_detach(dev);
+	if (error)
+		return error;
+
+	/* Disable the aperture.. */
+	pci_write_config(dev, AGP_SIS_WINCTRL,
+			 pci_read_config(dev, AGP_SIS_WINCTRL, 1) & ~3, 1);
+
+	/* and the TLB. */
+	pci_write_config(dev, AGP_SIS_TLBCTRL, 0, 1);
+
+	/* Put the aperture back the way it started. */
+	AGP_SET_APERTURE(dev, sc->initial_aperture);
+
+	agp_free_gatt(sc->gatt);
+	return 0;
+}
+
+static u_int32_t
+agp_sis_get_aperture(device_t dev)
+{
+	int gws;
+
+	/*
+	 * The aperture size is equal to 4M<<gws.
+	 */
+	gws = (pci_read_config(dev, AGP_SIS_WINCTRL, 1) & 0x70) >> 4;
+	return (4*1024*1024) << gws;
+}
+
+static int
+agp_sis_set_aperture(device_t dev, u_int32_t aperture)
+{
+	int gws;
+
+	/*
+	 * Check for a power of two and make sure its within the
+	 * programmable range.
+	 */
+	if (aperture & (aperture - 1)
+	    || aperture < 4*1024*1024
+	    || aperture > 256*1024*1024)
+		return EINVAL;
+
+	gws = ffs(aperture / 4*1024*1024) - 1;
+	
+	pci_write_config(dev, AGP_SIS_WINCTRL,
+			 ((pci_read_config(dev, AGP_SIS_WINCTRL, 1) & ~0x70)
+			  | gws << 4), 1);
+
+	return 0;
+}
+
+static int
+agp_sis_bind_page(device_t dev, int offset, vm_offset_t physical)
+{
+	struct agp_sis_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = physical;
+	return 0;
+}
+
+static int
+agp_sis_unbind_page(device_t dev, int offset)
+{
+	struct agp_sis_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = 0;
+	return 0;
+}
+
+static void
+agp_sis_flush_tlb(device_t dev)
+{
+	pci_write_config(dev, AGP_SIS_TLBFLUSH, 0x02, 1);
+}
+
+static device_method_t agp_sis_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		agp_sis_probe),
+	DEVMETHOD(device_attach,	agp_sis_attach),
+	DEVMETHOD(device_detach,	agp_sis_detach),
+	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
+	DEVMETHOD(device_suspend,	bus_generic_suspend),
+	DEVMETHOD(device_resume,	bus_generic_resume),
+
+	/* AGP interface */
+	DEVMETHOD(agp_get_aperture,	agp_sis_get_aperture),
+	DEVMETHOD(agp_set_aperture,	agp_sis_set_aperture),
+	DEVMETHOD(agp_bind_page,	agp_sis_bind_page),
+	DEVMETHOD(agp_unbind_page,	agp_sis_unbind_page),
+	DEVMETHOD(agp_flush_tlb,	agp_sis_flush_tlb),
+	DEVMETHOD(agp_enable,		agp_generic_enable),
+	DEVMETHOD(agp_alloc_memory,	agp_generic_alloc_memory),
+	DEVMETHOD(agp_free_memory,	agp_generic_free_memory),
+	DEVMETHOD(agp_bind_memory,	agp_generic_bind_memory),
+	DEVMETHOD(agp_unbind_memory,	agp_generic_unbind_memory),
+
+	{ 0, 0 }
+};
+
+static driver_t agp_sis_driver = {
+	"agp",
+	agp_sis_methods,
+	sizeof(struct agp_sis_softc),
+};
+
+static devclass_t agp_devclass;
+
+DRIVER_MODULE(agp_sis, pci, agp_sis_driver, agp_devclass, 0, 0);
diff --git a/sys/dev/agp/agp_via.c b/sys/dev/agp/agp_via.c
new file mode 100644
index 0000000..983348e
--- /dev/null
+++ b/sys/dev/agp/agp_via.c
@@ -0,0 +1,253 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#include "opt_bus.h"
+#include "opt_pci.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/kernel.h>
+#include <sys/bus.h>
+#include <sys/lock.h>
+
+#include <pci/pcivar.h>
+#include <pci/pcireg.h>
+#include <pci/agppriv.h>
+#include <pci/agpreg.h>
+
+#include <vm/vm.h>
+#include <vm/vm_object.h>
+#include <vm/pmap.h>
+
+struct agp_via_softc {
+	struct agp_softc agp;
+	u_int32_t	initial_aperture; /* aperture size at startup */
+	struct agp_gatt *gatt;
+};
+
+static const char*
+agp_via_match(device_t dev)
+{
+	if (pci_get_class(dev) != PCIC_BRIDGE
+	    || pci_get_subclass(dev) != PCIS_BRIDGE_HOST)
+		return NULL;
+
+	if (agp_find_caps(dev) == 0)
+		return NULL;
+
+	switch (pci_get_devid(dev)) {
+	case 0x05011106:
+		return ("VIA 8501 (Apollo MVP4) host to PCI bridge");
+	case 0x05971106:
+		return ("VIA 82C597 (Apollo VP3) host to PCI bridge");
+	case 0x05981106:
+		return ("VIA 82C598 (Apollo MVP3) host to PCI bridge");
+	case 0x06911106:
+		return ("VIA 82C691 (Apollo Pro) host to PCI bridge");
+	};
+
+	if (pci_get_vendor(dev) == 0x1106)
+		return ("VIA Generic host to PCI bridge");
+
+	return NULL;
+}
+
+static int
+agp_via_probe(device_t dev)
+{
+	const char *desc;
+
+	desc = agp_via_match(dev);
+	if (desc) {
+		device_verbose(dev);
+		device_set_desc(dev, desc);
+		return 0;
+	}
+
+	return ENXIO;
+}
+
+static int
+agp_via_attach(device_t dev)
+{
+	struct agp_via_softc *sc = device_get_softc(dev);
+	struct agp_gatt *gatt;
+	int error;
+
+	error = agp_generic_attach(dev);
+	if (error)
+		return error;
+
+	sc->initial_aperture = AGP_GET_APERTURE(dev);
+
+	for (;;) {
+		gatt = agp_alloc_gatt(dev);
+		if (gatt)
+			break;
+
+		/*
+		 * Probably contigmalloc failure. Try reducing the
+		 * aperture so that the gatt size reduces.
+		 */
+		if (AGP_SET_APERTURE(dev, AGP_GET_APERTURE(dev) / 2)) {
+			agp_generic_detach(dev);
+			return ENOMEM;
+		}
+	}
+	sc->gatt = gatt;
+
+	/* Install the gatt. */
+	pci_write_config(dev, AGP_VIA_ATTBASE, gatt->ag_physical | 3, 4);
+	
+	/* Enable the aperture. */
+	pci_write_config(dev, AGP_VIA_GARTCTRL, 0x0f, 4);
+
+	return 0;
+}
+
+static int
+agp_via_detach(device_t dev)
+{
+	struct agp_via_softc *sc = device_get_softc(dev);
+	int error;
+
+	error = agp_generic_detach(dev);
+	if (error)
+		return error;
+
+	pci_write_config(dev, AGP_VIA_GARTCTRL, 0, 4);
+	pci_write_config(dev, AGP_VIA_ATTBASE, 0, 4);
+	AGP_SET_APERTURE(dev, sc->initial_aperture);
+	agp_free_gatt(sc->gatt);
+
+	return 0;
+}
+
+static u_int32_t
+agp_via_get_aperture(device_t dev)
+{
+	u_int32_t apsize;
+
+	apsize = pci_read_config(dev, AGP_VIA_APSIZE, 1) & 0x1f;
+
+	/*
+	 * The size is determined by the number of low bits of
+	 * register APBASE which are forced to zero. The low 20 bits
+	 * are always forced to zero and each zero bit in the apsize
+	 * field just read forces the corresponding bit in the 27:20
+	 * to be zero. We calculate the aperture size accordingly.
+	 */
+	return (((apsize ^ 0xff) << 20) | ((1 << 20) - 1)) + 1;
+}
+
+static int
+agp_via_set_aperture(device_t dev, u_int32_t aperture)
+{
+	u_int32_t apsize;
+
+	/*
+	 * Reverse the magic from get_aperture.
+	 */
+	apsize = ((aperture - 1) >> 20) ^ 0xff;
+
+	/*
+	 * Double check for sanity.
+	 */
+	if ((((apsize ^ 0xff) << 20) | ((1 << 20) - 1)) + 1 != aperture)
+		return EINVAL;
+
+	pci_write_config(dev, AGP_VIA_APSIZE, apsize, 1);
+
+	return 0;
+}
+
+static int
+agp_via_bind_page(device_t dev, int offset, vm_offset_t physical)
+{
+	struct agp_via_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = physical;
+	return 0;
+}
+
+static int
+agp_via_unbind_page(device_t dev, int offset)
+{
+	struct agp_via_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = 0;
+	return 0;
+}
+
+static void
+agp_via_flush_tlb(device_t dev)
+{
+	pci_write_config(dev, AGP_VIA_GARTCTRL, 0x8f, 4);
+	pci_write_config(dev, AGP_VIA_GARTCTRL, 0x0f, 4);
+}
+
+static device_method_t agp_via_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		agp_via_probe),
+	DEVMETHOD(device_attach,	agp_via_attach),
+	DEVMETHOD(device_detach,	agp_via_detach),
+	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
+	DEVMETHOD(device_suspend,	bus_generic_suspend),
+	DEVMETHOD(device_resume,	bus_generic_resume),
+
+	/* AGP interface */
+	DEVMETHOD(agp_get_aperture,	agp_via_get_aperture),
+	DEVMETHOD(agp_set_aperture,	agp_via_set_aperture),
+	DEVMETHOD(agp_bind_page,	agp_via_bind_page),
+	DEVMETHOD(agp_unbind_page,	agp_via_unbind_page),
+	DEVMETHOD(agp_flush_tlb,	agp_via_flush_tlb),
+	DEVMETHOD(agp_enable,		agp_generic_enable),
+	DEVMETHOD(agp_alloc_memory,	agp_generic_alloc_memory),
+	DEVMETHOD(agp_free_memory,	agp_generic_free_memory),
+	DEVMETHOD(agp_bind_memory,	agp_generic_bind_memory),
+	DEVMETHOD(agp_unbind_memory,	agp_generic_unbind_memory),
+
+	{ 0, 0 }
+};
+
+static driver_t agp_via_driver = {
+	"agp",
+	agp_via_methods,
+	sizeof(struct agp_via_softc),
+};
+
+static devclass_t agp_devclass;
+
+DRIVER_MODULE(agp_via, pci, agp_via_driver, agp_devclass, 0, 0);
diff --git a/sys/dev/agp/agppriv.h b/sys/dev/agp/agppriv.h
new file mode 100644
index 0000000..427e68b
--- /dev/null
+++ b/sys/dev/agp/agppriv.h
@@ -0,0 +1,103 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#ifndef _PCI_AGPPRIV_H_
+#define _PCI_AGPPRIV_H_
+
+/*
+ * This file *must not* be included by code outside the agp driver itself.
+ */
+
+#include <sys/agpio.h>
+#include <pci/agpvar.h>
+
+#define AGP_DEBUGxx
+
+#ifdef AGP_DEBUG
+#define AGP_DPF(x...) do {			\
+    printf("agp: ");				\
+    printf(##x);				\
+} while (0)
+#else
+#define AGP_DPF(x...) do {} while (0)
+#endif
+
+#include "agp_if.h"
+
+/*
+ * Data structure to describe an AGP memory allocation.
+ */
+TAILQ_HEAD(agp_memory_list, agp_memory);
+struct agp_memory {
+	TAILQ_ENTRY(agp_memory) am_link;	/* wiring for the tailq */
+	int		am_id;			/* unique id for block */
+	vm_size_t	am_size;		/* number of bytes allocated */
+	struct vm_object *am_obj;		/* VM object owning pages */
+	vm_offset_t	am_physical;		/* bogus hack for i810 */
+	vm_offset_t	am_offset;		/* page offset if bound */
+	int		am_is_bound;		/* non-zero if bound */
+};
+
+/*
+ * All chipset drivers must have this at the start of their softc.
+ */
+struct agp_softc {
+	struct resource	        *as_aperture;	/* location of aperture */
+	u_int32_t		as_maxmem;	/* allocation upper bound */
+	u_int32_t		as_allocated;	/* amount allocated */
+	enum agp_acquire_state	as_state;
+	struct agp_memory_list	as_memory;	/* list of allocated memory */
+	int			as_nextid;	/* next memory block id */
+	int			as_isopen;	/* user device is open */
+	dev_t			as_devnode;	/* from make_dev */
+	struct lock		as_lock;	/* lock for access to GATT */
+};
+
+struct agp_gatt {
+	u_int32_t	ag_entries;
+	u_int32_t      *ag_virtual;
+	vm_offset_t	ag_physical;
+};
+
+u_int8_t		agp_find_caps(device_t dev);
+struct agp_gatt	       *agp_alloc_gatt(device_t dev);
+void		        agp_free_gatt(struct agp_gatt *gatt);
+int			agp_generic_attach(device_t dev);
+int			agp_generic_detach(device_t dev);
+int			agp_generic_enable(device_t dev, u_int32_t mode);
+struct agp_memory      *agp_generic_alloc_memory(device_t dev, int type,
+						 vm_size_t size);
+int			agp_generic_free_memory(device_t dev,
+						struct agp_memory *mem);
+int			agp_generic_bind_memory(device_t dev,
+						struct agp_memory *mem,
+						vm_offset_t offset);
+int			agp_generic_unbind_memory(device_t dev,
+						  struct agp_memory *mem);
+
+#endif /* !_PCI_AGPPRIV_H_ */
diff --git a/sys/dev/agp/agpreg.h b/sys/dev/agp/agpreg.h
new file mode 100644
index 0000000..0539325
--- /dev/null
+++ b/sys/dev/agp/agpreg.h
@@ -0,0 +1,109 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#ifndef _PCI_AGPREG_H_
+#define _PCI_AGPREG_H_
+
+/*
+ * Offsets for various AGP configuration registers.
+ */
+#define AGP_APBASE		0x10
+#define AGP_CAPPTR		0x34
+
+/*
+ * Offsets from the AGP Capability pointer.
+ */
+#define AGP_CAPID		0x0
+#define AGP_CAPID_GET_MAJOR(x)		(((x) & 0x00f00000U) >> 20)
+#define AGP_CAPID_GET_MINOR(x)		(((x) & 0x000f0000U) >> 16)
+#define AGP_CAPID_GET_NEXT_PTR(x)	(((x) & 0x0000ff00U) >> 8)
+#define AGP_CAPID_GET_CAP_ID(x)		(((x) & 0x000000ffU) >> 0)
+
+#define AGP_STATUS		0x4
+#define AGP_COMMAND		0x8
+
+/*
+ * Config offsets for Intel AGP chipsets.
+ */
+#define AGP_INTEL_NBXCFG	0x50
+#define AGP_INTEL_ERRSTS	0x91
+#define AGP_INTEL_AGPCTRL	0xb0
+#define AGP_INTEL_APSIZE	0xb4
+#define AGP_INTEL_ATTBASE	0xb8
+
+/*
+ * Config offsets for VIA AGP chipsets.
+ */
+#define AGP_VIA_GARTCTRL	0x80
+#define AGP_VIA_APSIZE		0x84
+#define AGP_VIA_ATTBASE		0x88
+
+/*
+ * Config offsets for SiS AGP chipsets.
+ */
+#define AGP_SIS_ATTBASE		0x90
+#define AGP_SIS_WINCTRL		0x94
+#define AGP_SIS_TLBCTRL		0x97
+#define AGP_SIS_TLBFLUSH	0x98
+
+/*
+ * Config offsets for Ali AGP chipsets.
+ */
+#define AGP_ALI_AGPCTRL		0xb8
+#define AGP_ALI_ATTBASE		0xbc
+#define AGP_ALI_TLBCTRL		0xc0
+
+/*
+ * Config offsets for the AMD 751 chipset.
+ */
+#define AGP_AMD751_REGISTERS	0x14
+#define AGP_AMD751_APCTRL	0xac
+#define AGP_AMD751_MODECTRL	0xb0
+
+/*
+ * Memory mapped register offsets for AMD 751 chipset.
+ */
+#define AGP_AMD751_CAPS		0x00
+#define AGP_AMD751_CAPS_EHI		0x0800
+#define AGP_AMD751_CAPS_P2P		0x0400
+#define AGP_AMD751_CAPS_MPC		0x0200
+#define AGP_AMD751_CAPS_VBE		0x0100
+#define AGP_AMD751_CAPS_REV		0x00ff
+#define AGP_AMD751_STATUS	0x02
+#define AGP_AMD751_STATUS_P2PS		0x0800
+#define AGP_AMD751_STATUS_GCS		0x0400
+#define AGP_AMD751_STATUS_MPS		0x0200
+#define AGP_AMD751_STATUS_VBES		0x0100
+#define AGP_AMD751_STATUS_P2PE		0x0008
+#define AGP_AMD751_STATUS_GCE		0x0004
+#define AGP_AMD751_STATUS_VBEE		0x0001
+#define AGP_AMD751_ATTBASE	0x04
+#define AGP_AMD751_TLBCTRL	0x0c
+
+
+#endif /* !_PCI_AGPREG_H_ */
diff --git a/sys/dev/agp/agpvar.h b/sys/dev/agp/agpvar.h
new file mode 100644
index 0000000..df3112b
--- /dev/null
+++ b/sys/dev/agp/agpvar.h
@@ -0,0 +1,125 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#ifndef _PCI_AGPVAR_H_
+#define _PCI_AGPVAR_H_
+
+/*
+ * The AGP chipset can be acquired by user or kernel code. If the
+ * chipset has already been acquired, it cannot be acquired by another 
+ * user until the previous user has released it.
+ */
+enum agp_acquire_state {
+	AGP_ACQUIRE_FREE,
+	AGP_ACQUIRE_USER,
+	AGP_ACQUIRE_KERNEL
+};
+
+/*
+ * This structure is used to query the state of the AGP system.
+ */
+struct agp_info {
+	u_int32_t	ai_mode;
+	vm_offset_t	ai_aperture_base;
+	vm_size_t	ai_aperture_size;
+	vm_size_t	ai_memory_allowed;
+	vm_size_t	ai_memory_used;
+	u_int32_t	ai_devid;
+};
+
+struct agp_memory_info {
+	vm_size_t	ami_size;	/* size in bytes */
+	vm_offset_t	ami_physical;	/* bogus hack for i810 */
+	vm_offset_t	ami_offset;	/* page offset if bound */
+	int		ami_is_bound;	/* non-zero if bound */
+};
+
+/*
+ * Find the AGP device and return it.
+ */
+device_t agp_find_device(void);
+
+/*
+ * Return the current owner of the AGP chipset.
+ */
+enum agp_acquire_state agp_state(device_t dev);
+
+/*
+ * Query the state of the AGP system.
+ */
+void agp_get_info(device_t dev, struct agp_info *info);
+
+/*
+ * Acquire the AGP chipset for use by the kernel. Returns EBUSY if the
+ * AGP chipset is already acquired by another user. 
+ */
+int agp_acquire(device_t dev);
+
+/*
+ * Release the AGP chipset.
+ */
+int agp_release(device_t dev);
+
+/*
+ * Enable the agp hardware with the relavent mode. The mode bits are
+ * defined in <pci/agpreg.h>
+ */
+int agp_enable(device_t dev, u_int32_t mode);
+
+/*
+ * Allocate physical memory suitable for mapping into the AGP
+ * aperture.  The value returned is an opaque handle which can be
+ * passed to agp_bind(), agp_unbind() or agp_deallocate().
+ */
+void *agp_alloc_memory(device_t dev, int type, vm_size_t bytes);
+
+/*
+ * Free memory which was allocated with agp_allocate().
+ */
+void agp_free_memory(device_t dev, void *handle);
+
+/*
+ * Bind memory allocated with agp_allocate() at a given offset within
+ * the AGP aperture. Returns EINVAL if the memory is already bound or
+ * the offset is not at an AGP page boundary.
+ */
+int agp_bind_memory(device_t dev, void *handle, vm_offset_t offset);
+
+/*
+ * Unbind memory from the AGP aperture. Returns EINVAL if the memory
+ * is not bound.
+ */
+int agp_unbind_memory(device_t dev, void *handle);
+
+/*
+ * Retrieve information about a memory block allocated with
+ * agp_alloc_memory().
+ */
+void agp_memory_info(device_t dev, void *handle, struct agp_memory_info *mi);
+
+#endif /* !_PCI_AGPVAR_H_ */
diff --git a/sys/pci/agp.c b/sys/pci/agp.c
new file mode 100644
index 0000000..e1d6583
--- /dev/null
+++ b/sys/pci/agp.c
@@ -0,0 +1,790 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#include "opt_bus.h"
+#include "opt_pci.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/kernel.h>
+#include <sys/bus.h>
+#include <sys/conf.h>
+#include <sys/ioccom.h>
+#include <sys/agpio.h>
+#include <sys/lock.h>
+#include <sys/proc.h>
+
+#include <pci/pcivar.h>
+#include <pci/pcireg.h>
+#include <pci/agppriv.h>
+#include <pci/agpvar.h>
+#include <pci/agpreg.h>
+
+#include <vm/vm.h>
+#include <vm/vm_object.h>
+#include <vm/vm_page.h>
+#include <vm/vm_pageout.h>
+#include <vm/pmap.h>
+
+#include <machine/md_var.h>
+#include <machine/bus.h>
+#include <machine/resource.h>
+#include <sys/rman.h>
+
+MODULE_VERSION(agp, 1);
+
+MALLOC_DEFINE(M_AGP, "agp", "AGP data structures");
+
+#define CDEV_MAJOR	148
+				/* agp_drv.c */
+static d_open_t agp_open;
+static d_close_t agp_close;
+static d_ioctl_t agp_ioctl;
+static d_mmap_t agp_mmap;
+
+static struct cdevsw agp_cdevsw = {
+	/* open */	agp_open,
+	/* close */	agp_close,
+	/* read */	noread,
+	/* write */	nowrite,
+	/* ioctl */	agp_ioctl,
+	/* poll */	nopoll,
+	/* mmap */	agp_mmap,
+	/* strategy */	nostrategy,
+	/* name */	"agp",
+	/* maj */	CDEV_MAJOR,
+	/* dump */	nodump,
+	/* psize */	nopsize,
+	/* flags */	D_TTY,
+	/* bmaj */	-1
+};
+
+static devclass_t agp_devclass;
+#define KDEV2DEV(kdev)	devclass_get_device(agp_devclass, minor(kdev))
+
+/* Helper functions for implementing chipset mini drivers. */
+
+#ifdef __i386__
+#define agp_flush_cache()	wbinvd()
+#endif
+
+u_int8_t
+agp_find_caps(device_t dev)
+{
+	u_int32_t status;
+	u_int8_t ptr, next;
+
+	/*
+	 * Check the CAP_LIST bit of the PCI status register first.
+	 */
+	status = pci_read_config(dev, PCIR_STATUS, 2);
+	if (!(status & 0x10))
+		return 0;
+
+	/*
+	 * Traverse the capabilities list.
+	 */
+	for (ptr = pci_read_config(dev, AGP_CAPPTR, 1);
+	     ptr != 0;
+	     ptr = next) {
+		u_int32_t capid = pci_read_config(dev, ptr, 4);
+		next = AGP_CAPID_GET_NEXT_PTR(capid);
+
+		/*
+		 * If this capability entry ID is 2, then we are done.
+		 */
+		if (AGP_CAPID_GET_CAP_ID(capid) == 2)
+			return ptr;
+	}
+
+	return 0;
+}
+
+/*
+ * Find an AGP display device (if any).
+ */
+static device_t
+agp_find_display(void)
+{
+	devclass_t pci = devclass_find("pci");
+	device_t bus, dev = 0;
+	device_t *kids;
+	int busnum, numkids, i;
+
+	for (busnum = 0; busnum < devclass_get_maxunit(pci); busnum++) {
+		bus = devclass_get_device(pci, busnum);
+		if (!bus)
+			continue;
+		device_get_children(bus, &kids, &numkids);
+		for (i = 0; i < numkids; i++) {
+			dev = kids[i];
+			if (pci_get_class(dev) == PCIC_DISPLAY
+			    && pci_get_subclass(dev) == PCIS_DISPLAY_VGA)
+				if (agp_find_caps(dev)) {
+					free(kids, M_TEMP);
+					return dev;
+				}
+					
+		}
+		free(kids, M_TEMP);
+	}
+
+	return 0;
+}
+
+struct agp_gatt *
+agp_alloc_gatt(device_t dev)
+{
+	u_int32_t apsize = AGP_GET_APERTURE(dev);
+	u_int32_t entries = apsize >> AGP_PAGE_SHIFT;
+	struct agp_gatt *gatt;
+
+	if (bootverbose)
+		device_printf(dev,
+			      "allocating GATT for aperture of size %dM\n",
+			      apsize / (1024*1024));
+
+	gatt = malloc(sizeof(struct agp_gatt), M_AGP, M_NOWAIT);
+	if (!gatt)
+		return 0;
+
+	gatt->ag_entries = entries;
+	gatt->ag_virtual = contigmalloc(entries * sizeof(u_int32_t), M_AGP, 0,
+					0, ~0, PAGE_SIZE, 0);
+	if (!gatt->ag_virtual) {
+		if (bootverbose)
+			device_printf(dev, "contiguous allocation failed\n");
+		free(gatt, M_AGP);
+		return 0;
+	}
+	bzero(gatt->ag_virtual, entries * sizeof(u_int32_t));
+	gatt->ag_physical = vtophys((vm_offset_t) gatt->ag_virtual);
+	agp_flush_cache();
+
+	return gatt;
+}
+
+void
+agp_free_gatt(struct agp_gatt *gatt)
+{
+	contigfree(gatt->ag_virtual,
+		   gatt->ag_entries * sizeof(u_int32_t), M_AGP);
+	free(gatt, M_AGP);
+}
+
+static int agp_max[][2] = {
+	{0,	0},
+	{32,	4},
+	{64,	28},
+	{128,	96},
+	{256,	204},
+	{512,	440},
+	{1024,	942},
+	{2048,	1920},
+	{4096,	3932}
+};
+#define agp_max_size	(sizeof(agp_max) / sizeof(agp_max[0]))
+
+int
+agp_generic_attach(device_t dev)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+	int rid, memsize, i;
+
+	/*
+	 * Find and map the aperture.
+	 */
+	rid = AGP_APBASE;
+	sc->as_aperture = bus_alloc_resource(dev, SYS_RES_MEMORY, &rid,
+					     0, ~0, 1, RF_ACTIVE);
+	if (!sc->as_aperture)
+		return ENOMEM;
+
+	/*
+	 * Work out an upper bound for agp memory allocation. This
+	 * uses a heurisitc table from the Linux driver.
+	 */
+	memsize = ptoa(Maxmem) >> 20;
+	for (i = 0; i < agp_max_size; i++) {
+		if (memsize <= agp_max[i][0])
+			break;
+	}
+	if (i == agp_max_size) i = agp_max_size - 1;
+	sc->as_maxmem = agp_max[i][1] << 20U;
+
+	/*
+	 * The lock is used to prevent re-entry to
+	 * agp_generic_bind_memory() since that function can sleep.
+	 */
+	lockinit(&sc->as_lock, PZERO|PCATCH, "agplk", 0, 0);
+
+	/*
+	 * Initialise stuff for the userland device.
+	 */
+	agp_devclass = devclass_find("agp");
+	TAILQ_INIT(&sc->as_memory);
+	sc->as_nextid = 1;
+
+	sc->as_devnode = make_dev(&agp_cdevsw,
+				  device_get_unit(dev),
+				  UID_ROOT,
+				  GID_WHEEL,
+				  0600,
+				  "agpgart");
+
+	return 0;
+}
+
+int
+agp_generic_detach(device_t dev)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+	bus_release_resource(dev, SYS_RES_MEMORY, AGP_APBASE, sc->as_aperture);
+	lockmgr(&sc->as_lock, LK_DRAIN, 0, curproc);
+	destroy_dev(sc->as_devnode);
+	agp_flush_cache();
+	return 0;
+}
+
+int
+agp_generic_enable(device_t dev, u_int32_t mode)
+{
+	device_t mdev = agp_find_display();
+	u_int32_t tstatus, mstatus;
+	u_int32_t command;
+	int rq, sba, fw, rate;;
+
+	if (!mdev) {
+		AGP_DPF("can't find display\n");
+		return ENXIO;
+	}
+
+	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
+	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
+
+	/* Set RQ to the min of mode, tstatus and mstatus */
+	rq = AGP_MODE_GET_RQ(mode);
+	if (AGP_MODE_GET_RQ(tstatus) < rq)
+		rq = AGP_MODE_GET_RQ(tstatus);
+	if (AGP_MODE_GET_RQ(mstatus) < rq)
+		rq = AGP_MODE_GET_RQ(mstatus);
+
+	/* Set SBA if all three can deal with SBA */
+	sba = (AGP_MODE_GET_SBA(tstatus)
+	       & AGP_MODE_GET_SBA(mstatus)
+	       & AGP_MODE_GET_SBA(mode));
+
+	/* Similar for FW */
+	fw = (AGP_MODE_GET_FW(tstatus)
+	       & AGP_MODE_GET_FW(mstatus)
+	       & AGP_MODE_GET_FW(mode));
+
+	/* Figure out the max rate */
+	rate = (AGP_MODE_GET_RATE(tstatus)
+		& AGP_MODE_GET_RATE(mstatus)
+		& AGP_MODE_GET_RATE(mode));
+	if (rate & AGP_MODE_RATE_4x)
+		rate = AGP_MODE_RATE_4x;
+	else if (rate & AGP_MODE_RATE_2x)
+		rate = AGP_MODE_RATE_2x;
+	else
+		rate = AGP_MODE_RATE_1x;
+
+	/* Construct the new mode word and tell the hardware */
+	command = AGP_MODE_SET_RQ(0, rq);
+	command = AGP_MODE_SET_SBA(command, sba);
+	command = AGP_MODE_SET_FW(command, fw);
+	command = AGP_MODE_SET_RATE(command, rate);
+	command = AGP_MODE_SET_AGP(command, 1);
+	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
+	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
+
+	return 0;
+}
+
+struct agp_memory *
+agp_generic_alloc_memory(device_t dev, int type, vm_size_t size)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+	struct agp_memory *mem;
+
+	if ((size & (AGP_PAGE_SIZE - 1)) != 0)
+		return 0;
+
+	if (sc->as_allocated + size > sc->as_maxmem)
+		return 0;
+
+	mem = malloc(sizeof *mem, M_AGP, M_WAITOK);
+	mem->am_id = sc->as_nextid++;
+	mem->am_size = size;
+	mem->am_obj = vm_object_allocate(OBJT_DEFAULT, atop(round_page(size)));
+	mem->am_physical = 0;
+	mem->am_offset = 0;
+	mem->am_is_bound = 0;
+	TAILQ_INSERT_TAIL(&sc->as_memory, mem, am_link);
+	sc->as_allocated += size;
+
+	return mem;
+}
+
+int
+agp_generic_free_memory(device_t dev, struct agp_memory *mem)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+
+	if (mem->am_is_bound)
+		return EBUSY;
+
+	sc->as_allocated -= mem->am_size;
+	TAILQ_REMOVE(&sc->as_memory, mem, am_link);
+	vm_object_deallocate(mem->am_obj);
+	free(mem, M_AGP);
+	return 0;
+}
+
+int
+agp_generic_bind_memory(device_t dev, struct agp_memory *mem,
+			vm_offset_t offset)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+	vm_offset_t i, j, k;
+	vm_page_t m;
+	int error;
+
+	lockmgr(&sc->as_lock, LK_EXCLUSIVE, 0, curproc);
+
+	if (mem->am_is_bound) {
+		device_printf(dev, "memory already bound\n");
+		return EINVAL;
+	}
+	
+	if (offset < 0
+	    || (offset & (AGP_PAGE_SIZE - 1)) != 0
+	    || offset + mem->am_size > AGP_GET_APERTURE(dev)) {
+		device_printf(dev, "binding memory at bad offset %#x\n",
+			      (int) offset);
+		return EINVAL;
+	}
+
+	/*
+	 * Bind the individual pages and flush the chipset's
+	 * TLB.
+	 *
+	 * XXX Presumably, this needs to be the pci address on alpha
+	 * (i.e. use alpha_XXX_dmamap()). I don't have access to any
+	 * alpha AGP hardware to check.
+	 */
+	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
+		/*
+		 * Find a page from the object and wire it
+		 * down. This page will be mapped using one or more
+		 * entries in the GATT (assuming that PAGE_SIZE >=
+		 * AGP_PAGE_SIZE. If this is the first call to bind,
+		 * the pages will be allocated and zeroed.
+		 */
+		m = vm_page_grab(mem->am_obj, OFF_TO_IDX(i),
+				 VM_ALLOC_ZERO | VM_ALLOC_RETRY);
+		AGP_DPF("found page pa=%#x\n", VM_PAGE_TO_PHYS(m));
+		vm_page_wire(m);
+
+		/*
+		 * Install entries in the GATT, making sure that if
+		 * AGP_PAGE_SIZE < PAGE_SIZE and mem->am_size is not
+		 * aligned to PAGE_SIZE, we don't modify too many GATT 
+		 * entries.
+		 */
+		for (j = 0; j < PAGE_SIZE && i + j < mem->am_size;
+		     j += AGP_PAGE_SIZE) {
+			vm_offset_t pa = VM_PAGE_TO_PHYS(m) + j;
+			AGP_DPF("binding offset %#x to pa %#x\n",
+				offset + i + j, pa);
+			error = AGP_BIND_PAGE(dev, offset + i + j, pa);
+			if (error) {
+				/*
+				 * Bail out. Reverse all the mappings
+				 * and unwire the pages.
+				 */
+				vm_page_wakeup(m);
+				for (k = 0; k < i + j; k += AGP_PAGE_SIZE)
+					AGP_UNBIND_PAGE(dev, offset + k);
+				for (k = 0; k <= i; k += PAGE_SIZE) {
+					m = vm_page_lookup(mem->am_obj,
+							   OFF_TO_IDX(k));
+					vm_page_unwire(m, 0);
+				}
+				lockmgr(&sc->as_lock, LK_RELEASE, 0, curproc);
+				return error;
+			}
+		}
+		vm_page_wakeup(m);
+	}
+
+	/*
+	 * Flush the cpu cache since we are providing a new mapping
+	 * for these pages.
+	 */
+	agp_flush_cache();
+
+	/*
+	 * Make sure the chipset gets the new mappings.
+	 */
+	AGP_FLUSH_TLB(dev);
+
+	mem->am_offset = offset;
+	mem->am_is_bound = 1;
+
+	lockmgr(&sc->as_lock, LK_RELEASE, 0, curproc);
+
+	return 0;
+}
+
+int
+agp_generic_unbind_memory(device_t dev, struct agp_memory *mem)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+	vm_page_t m;
+	int i;
+
+	lockmgr(&sc->as_lock, LK_EXCLUSIVE, 0, curproc);
+
+	if (!mem->am_is_bound) {
+		device_printf(dev, "memory is not bound\n");
+		return EINVAL;
+	}
+
+
+	/*
+	 * Unbind the individual pages and flush the chipset's
+	 * TLB. Unwire the pages so they can be swapped.
+	 */
+	for (i = 0; i < mem->am_size; i += AGP_PAGE_SIZE)
+		AGP_UNBIND_PAGE(dev, mem->am_offset + i);
+	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
+		m = vm_page_lookup(mem->am_obj, atop(i));
+		vm_page_unwire(m, 0);
+	}
+		
+	agp_flush_cache();
+	AGP_FLUSH_TLB(dev);
+
+	mem->am_offset = 0;
+	mem->am_is_bound = 0;
+
+	lockmgr(&sc->as_lock, LK_RELEASE, 0, curproc);
+
+	return 0;
+}
+
+/* Helper functions for implementing user/kernel api */
+
+static int
+agp_acquire_helper(device_t dev, enum agp_acquire_state state)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+
+	if (sc->as_state != AGP_ACQUIRE_FREE)
+		return EBUSY;
+	sc->as_state = state;
+
+	return 0;
+}
+
+static int
+agp_release_helper(device_t dev, enum agp_acquire_state state)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+	struct agp_memory *mem;
+
+	if (sc->as_state == AGP_ACQUIRE_FREE)
+		return 0;
+
+	if (sc->as_state != state)
+		return EBUSY;
+
+	/*
+	 * Clear out the aperture and free any outstanding memory blocks.
+	 */
+	while ((mem = TAILQ_FIRST(&sc->as_memory)) != 0) {
+		if (mem->am_is_bound)
+			AGP_UNBIND_MEMORY(dev, mem);
+		AGP_FREE_MEMORY(dev, mem);
+	}
+
+	sc->as_state = AGP_ACQUIRE_FREE;
+	return 0;
+}
+
+static struct agp_memory *
+agp_find_memory(device_t dev, int id)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+	struct agp_memory *mem;
+
+	AGP_DPF("searching for memory block %d\n", id);
+	TAILQ_FOREACH(mem, &sc->as_memory, am_link) {
+		AGP_DPF("considering memory block %d\n", mem->am_id);
+		if (mem->am_id == id)
+			return mem;
+	}
+	return 0;
+}
+
+/* Implementation of the userland ioctl api */
+
+static int
+agp_info_user(device_t dev, agp_info *info)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+
+	bzero(info, sizeof *info);
+	info->bridge_id = pci_get_devid(dev);
+	info->agp_mode = 
+	    pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
+	info->aper_base = rman_get_start(sc->as_aperture);
+	info->aper_size = AGP_GET_APERTURE(dev) >> 20;
+	info->pg_total = info->pg_system = sc->as_maxmem >> AGP_PAGE_SHIFT;
+	info->pg_used = sc->as_allocated >> AGP_PAGE_SHIFT;
+
+	return 0;
+}
+
+static int
+agp_setup_user(device_t dev, agp_setup *setup)
+{
+	return AGP_ENABLE(dev, setup->agp_mode);
+}
+
+static int
+agp_allocate_user(device_t dev, agp_allocate *alloc)
+{
+	struct agp_memory *mem;
+
+	mem = AGP_ALLOC_MEMORY(dev,
+			       alloc->type,
+			       alloc->pg_count << AGP_PAGE_SHIFT);
+	alloc->key = mem->am_id;
+	alloc->physical = mem->am_physical;
+
+	return 0;
+}
+
+static int
+agp_deallocate_user(device_t dev, int id)
+{
+	struct agp_memory *mem = agp_find_memory(dev, id);;
+
+	if (mem) {
+		AGP_FREE_MEMORY(dev, mem);
+		return 0;
+	} else {
+		return ENOENT;
+	}
+}
+
+static int
+agp_bind_user(device_t dev, agp_bind *bind)
+{
+	struct agp_memory *mem = agp_find_memory(dev, bind->key);
+
+	if (!mem)
+		return ENOENT;
+
+	return AGP_BIND_MEMORY(dev, mem, bind->pg_start << AGP_PAGE_SHIFT);
+}
+
+static int
+agp_unbind_user(device_t dev, agp_unbind *unbind)
+{
+	struct agp_memory *mem = agp_find_memory(dev, unbind->key);
+
+	if (!mem)
+		return ENOENT;
+
+	return AGP_UNBIND_MEMORY(dev, mem);
+}
+
+static int
+agp_open(dev_t kdev, int oflags, int devtype, struct proc *p)
+{
+	device_t dev = KDEV2DEV(kdev);
+	struct agp_softc *sc = device_get_softc(dev);
+
+	if (!sc->as_isopen) {
+		sc->as_isopen = 1;
+		device_busy(dev);
+	}
+
+	return 0;
+}
+
+static int
+agp_close(dev_t kdev, int fflag, int devtype, struct proc *p)
+{
+	device_t dev = KDEV2DEV(kdev);
+	struct agp_softc *sc = device_get_softc(dev);
+
+	/*
+	 * Clear the GATT and force release on last close
+	 */
+	if (sc->as_state == AGP_ACQUIRE_USER)
+		agp_release_helper(dev, AGP_ACQUIRE_USER);
+	sc->as_isopen = 0;
+	device_unbusy(dev);
+
+	return 0;
+}
+
+static int
+agp_ioctl(dev_t kdev, u_long cmd, caddr_t data, int fflag, struct proc *p)
+{
+	device_t dev = KDEV2DEV(kdev);
+
+	switch (cmd) {
+	case AGPIOC_INFO:
+		return agp_info_user(dev, (agp_info *) data);
+
+	case AGPIOC_ACQUIRE:
+		return agp_acquire_helper(dev, AGP_ACQUIRE_USER);
+
+	case AGPIOC_RELEASE:
+		return agp_release_helper(dev, AGP_ACQUIRE_USER);
+
+	case AGPIOC_SETUP:
+		return agp_setup_user(dev, (agp_setup *)data);
+
+	case AGPIOC_ALLOCATE:
+		return agp_allocate_user(dev, (agp_allocate *)data);
+
+	case AGPIOC_DEALLOCATE:
+		return agp_deallocate_user(dev, *(int *) data);
+
+	case AGPIOC_BIND:
+		return agp_bind_user(dev, (agp_bind *)data);
+
+	case AGPIOC_UNBIND:
+		return agp_unbind_user(dev, (agp_unbind *)data);
+
+	}
+
+	return EINVAL;
+}
+
+static int
+agp_mmap(dev_t kdev, vm_offset_t offset, int prot)
+{
+	device_t dev = KDEV2DEV(kdev);
+	struct agp_softc *sc = device_get_softc(dev);
+
+	if (offset > AGP_GET_APERTURE(dev))
+		return -1;
+	return atop(rman_get_start(sc->as_aperture) + offset);
+}
+
+/* Implementation of the kernel api */
+
+device_t
+agp_find_device()
+{
+	if (!agp_devclass)
+		return 0;
+	return devclass_get_device(agp_devclass, 0);
+}
+
+enum agp_acquire_state
+agp_state(device_t dev)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+	return sc->as_state;
+}
+
+void
+agp_get_info(device_t dev, struct agp_info *info)
+{
+	struct agp_softc *sc = device_get_softc(dev);
+
+	info->ai_mode =
+		pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
+	info->ai_aperture_base = rman_get_start(sc->as_aperture);
+	info->ai_aperture_size = (rman_get_end(sc->as_aperture)
+				  - rman_get_start(sc->as_aperture)) + 1;
+	info->ai_memory_allowed = sc->as_maxmem;
+	info->ai_memory_used = sc->as_allocated;
+}
+
+int
+agp_acquire(device_t dev)
+{
+	return agp_acquire_helper(dev, AGP_ACQUIRE_KERNEL);
+}
+
+int
+agp_release(device_t dev)
+{
+	return agp_release_helper(dev, AGP_ACQUIRE_KERNEL);
+}
+
+int
+agp_enable(device_t dev, u_int32_t mode)
+{
+	return AGP_ENABLE(dev, mode);
+}
+
+void *agp_alloc_memory(device_t dev, int type, vm_size_t bytes)
+{
+	return  (void *) AGP_ALLOC_MEMORY(dev, type, bytes);
+}
+
+void agp_free_memory(device_t dev, void *handle)
+{
+	struct agp_memory *mem = (struct agp_memory *) handle;
+	AGP_FREE_MEMORY(dev, mem);
+}
+
+int agp_bind_memory(device_t dev, void *handle, vm_offset_t offset)
+{
+	struct agp_memory *mem = (struct agp_memory *) handle;
+	return AGP_BIND_MEMORY(dev, mem, offset);
+}
+
+int agp_unbind_memory(device_t dev, void *handle)
+{
+	struct agp_memory *mem = (struct agp_memory *) handle;
+	return AGP_UNBIND_MEMORY(dev, mem);
+}
+
+void agp_memory_info(device_t dev, void *handle, struct
+		     agp_memory_info *mi)
+{
+	struct agp_memory *mem = (struct agp_memory *) handle;
+
+	mi->ami_size = mem->am_size;
+	mi->ami_physical = mem->am_physical;
+	mi->ami_offset = mem->am_offset;
+	mi->ami_is_bound = mem->am_is_bound;
+}
diff --git a/sys/pci/agp_ali.c b/sys/pci/agp_ali.c
new file mode 100644
index 0000000..86e070e
--- /dev/null
+++ b/sys/pci/agp_ali.c
@@ -0,0 +1,264 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#include "opt_bus.h"
+#include "opt_pci.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/kernel.h>
+#include <sys/bus.h>
+#include <sys/lock.h>
+
+#include <pci/pcivar.h>
+#include <pci/pcireg.h>
+#include <pci/agppriv.h>
+#include <pci/agpreg.h>
+
+#include <vm/vm.h>
+#include <vm/vm_object.h>
+#include <vm/pmap.h>
+
+struct agp_ali_softc {
+	struct agp_softc agp;
+	u_int32_t	initial_aperture; /* aperture size at startup */
+	struct agp_gatt *gatt;
+};
+
+static const char*
+agp_ali_match(device_t dev)
+{
+	if (pci_get_class(dev) != PCIC_BRIDGE
+	    || pci_get_subclass(dev) != PCIS_BRIDGE_HOST)
+		return NULL;
+
+	if (agp_find_caps(dev) == 0)
+		return NULL;
+
+	switch (pci_get_devid(dev)) {
+	case 0x154110b9:
+		return ("Ali M1541 host to AGP bridge");
+	};
+
+	if (pci_get_vendor(dev) == 0x10b9)
+		return ("Ali Generic host to PCI bridge");
+
+	return NULL;
+}
+
+static int
+agp_ali_probe(device_t dev)
+{
+	const char *desc;
+
+	desc = agp_ali_match(dev);
+	if (desc) {
+		device_verbose(dev);
+		device_set_desc(dev, desc);
+		return 0;
+	}
+
+	return ENXIO;
+}
+
+static int
+agp_ali_attach(device_t dev)
+{
+	struct agp_ali_softc *sc = device_get_softc(dev);
+	struct agp_gatt *gatt;
+	int error;
+
+	error = agp_generic_attach(dev);
+	if (error)
+		return error;
+
+	sc->initial_aperture = AGP_GET_APERTURE(dev);
+
+	for (;;) {
+		gatt = agp_alloc_gatt(dev);
+		if (gatt)
+			break;
+
+		/*
+		 * Probably contigmalloc failure. Try reducing the
+		 * aperture so that the gatt size reduces.
+		 */
+		if (AGP_SET_APERTURE(dev, AGP_GET_APERTURE(dev) / 2)) {
+			agp_generic_detach(dev);
+			return ENOMEM;
+		}
+	}
+	sc->gatt = gatt;
+
+	/* Install the gatt. */
+	pci_write_config(dev, AGP_ALI_ATTBASE,
+			 (gatt->ag_physical
+			  | (pci_read_config(dev, AGP_ALI_ATTBASE, 4) & 0xff)),
+			 4);
+	
+	/* Enable the TLB. */
+	pci_write_config(dev, AGP_ALI_TLBCTRL, 0x10, 1);
+
+	return 0;
+}
+
+static int
+agp_ali_detach(device_t dev)
+{
+	struct agp_ali_softc *sc = device_get_softc(dev);
+	int error;
+
+	error = agp_generic_detach(dev);
+	if (error)
+		return error;
+
+	/* Disable the TLB.. */
+	pci_write_config(dev, AGP_ALI_TLBCTRL, 0x90, 1);
+
+	/* Put the aperture back the way it started. */
+	AGP_SET_APERTURE(dev, sc->initial_aperture);
+	pci_write_config(dev, AGP_ALI_ATTBASE,
+			 pci_read_config(dev, AGP_ALI_ATTBASE, 4) & 0xff,
+			 4);
+
+	agp_free_gatt(sc->gatt);
+	return 0;
+}
+
+#define M 1024*1024
+
+static u_int32_t agp_ali_table[] = {
+	0,			/* 0 - invalid */
+	1,			/* 1 - invalid */
+	2,			/* 2 - invalid */
+	4*M,			/* 3 - invalid */
+	8*M,			/* 4 - invalid */
+	0,			/* 5 - invalid */
+	16*M,			/* 6 - invalid */
+	32*M,			/* 7 - invalid */
+	64*M,			/* 8 - invalid */
+	128*M,			/* 9 - invalid */
+	256*M,			/* 10 - invalid */
+};
+#define agp_ali_table_size (sizeof(agp_ali_table) / sizeof(agp_ali_table[0]))
+
+static u_int32_t
+agp_ali_get_aperture(device_t dev)
+{
+	/*
+	 * The aperture size is derived from the low bits of attbase.
+	 * I'm not sure this is correct..
+	 */
+	int i = pci_read_config(dev, AGP_ALI_ATTBASE, 4) & 0xff;
+	if (i >= agp_ali_table_size)
+		return 0;
+	return agp_ali_table[i];
+}
+
+static int
+agp_ali_set_aperture(device_t dev, u_int32_t aperture)
+{
+	int i;
+
+	for (i = 0; i < agp_ali_table_size; i++)
+		if (agp_ali_table[i] == aperture)
+			break;
+	if (i == agp_ali_table_size)
+		return EINVAL;
+
+	pci_write_config(dev, AGP_ALI_ATTBASE,
+			 ((pci_read_config(dev, AGP_ALI_ATTBASE, 4) & ~0xff)
+			  | i), 4);
+	return 0;
+}
+
+static int
+agp_ali_bind_page(device_t dev, int offset, vm_offset_t physical)
+{
+	struct agp_ali_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = physical;
+	return 0;
+}
+
+static int
+agp_ali_unbind_page(device_t dev, int offset)
+{
+	struct agp_ali_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = 0;
+	return 0;
+}
+
+static void
+agp_ali_flush_tlb(device_t dev)
+{
+	pci_write_config(dev, AGP_ALI_TLBCTRL, 0x90, 1);
+	pci_write_config(dev, AGP_ALI_TLBCTRL, 0x10, 1);
+}
+
+static device_method_t agp_ali_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		agp_ali_probe),
+	DEVMETHOD(device_attach,	agp_ali_attach),
+	DEVMETHOD(device_detach,	agp_ali_detach),
+	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
+	DEVMETHOD(device_suspend,	bus_generic_suspend),
+	DEVMETHOD(device_resume,	bus_generic_resume),
+
+	/* AGP interface */
+	DEVMETHOD(agp_get_aperture,	agp_ali_get_aperture),
+	DEVMETHOD(agp_set_aperture,	agp_ali_set_aperture),
+	DEVMETHOD(agp_bind_page,	agp_ali_bind_page),
+	DEVMETHOD(agp_unbind_page,	agp_ali_unbind_page),
+	DEVMETHOD(agp_flush_tlb,	agp_ali_flush_tlb),
+	DEVMETHOD(agp_enable,		agp_generic_enable),
+	DEVMETHOD(agp_alloc_memory,	agp_generic_alloc_memory),
+	DEVMETHOD(agp_free_memory,	agp_generic_free_memory),
+	DEVMETHOD(agp_bind_memory,	agp_generic_bind_memory),
+	DEVMETHOD(agp_unbind_memory,	agp_generic_unbind_memory),
+
+	{ 0, 0 }
+};
+
+static driver_t agp_ali_driver = {
+	"agp",
+	agp_ali_methods,
+	sizeof(struct agp_ali_softc),
+};
+
+static devclass_t agp_devclass;
+
+DRIVER_MODULE(agp_ali, pci, agp_ali_driver, agp_devclass, 0, 0);
diff --git a/sys/pci/agp_amd.c b/sys/pci/agp_amd.c
new file mode 100644
index 0000000..112918a
--- /dev/null
+++ b/sys/pci/agp_amd.c
@@ -0,0 +1,276 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#include "opt_bus.h"
+#include "opt_pci.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/kernel.h>
+#include <sys/bus.h>
+#include <sys/lock.h>
+
+#include <pci/pcivar.h>
+#include <pci/pcireg.h>
+#include <pci/agppriv.h>
+#include <pci/agpreg.h>
+
+#include <vm/vm.h>
+#include <vm/vm_object.h>
+#include <vm/pmap.h>
+#include <machine/clock.h>
+#include <machine/bus.h>
+#include <machine/resource.h>
+#include <sys/rman.h>
+
+#define READ2(off)	bus_space_read_2(sc->bst, sc->bsh, off)
+#define READ4(off)	bus_space_read_4(sc->bst, sc->bsh, off)
+#define WRITE2(off,v)	bus_space_write_2(sc->bst, sc->bsh, off, v)
+#define WRITE4(off,v)	bus_space_write_4(sc->bst, sc->bsh, off, v)
+
+struct agp_amd_softc {
+	struct agp_softc agp;
+	struct resource *regs;	/* memory mapped control registers */
+	bus_space_tag_t bst;	/* bus_space tag */
+	bus_space_handle_t bsh;	/* bus_space handle */
+	u_int32_t	initial_aperture; /* aperture size at startup */
+	struct agp_gatt *gatt;
+};
+
+static const char*
+agp_amd_match(device_t dev)
+{
+	if (pci_get_class(dev) != PCIC_BRIDGE
+	    || pci_get_subclass(dev) != PCIS_BRIDGE_HOST)
+		return NULL;
+
+	if (agp_find_caps(dev) == 0)
+		return NULL;
+
+	switch (pci_get_devid(dev)) {
+	case 0x70061022:
+		return ("AMD 751 host to AGP bridge");
+	};
+
+	return NULL;
+}
+
+static int
+agp_amd_probe(device_t dev)
+{
+	const char *desc;
+
+	desc = agp_amd_match(dev);
+	if (desc) {
+		device_verbose(dev);
+		device_set_desc(dev, desc);
+		return 0;
+	}
+
+	return ENXIO;
+}
+
+static int
+agp_amd_attach(device_t dev)
+{
+	struct agp_amd_softc *sc = device_get_softc(dev);
+	struct agp_gatt *gatt;
+	int error, rid;
+
+	error = agp_generic_attach(dev);
+	if (error)
+		return error;
+
+	rid = AGP_AMD751_REGISTERS;
+	sc->regs = bus_alloc_resource(dev, SYS_RES_MEMORY, &rid,
+				      0, ~0, 1, RF_ACTIVE);
+	if (!sc->regs) {
+		agp_generic_detach(dev);
+		return ENOMEM;
+	}
+
+	sc->bst = rman_get_bustag(sc->regs);
+	sc->bsh = rman_get_bushandle(sc->regs);
+
+	sc->initial_aperture = AGP_GET_APERTURE(dev);
+
+	for (;;) {
+		gatt = agp_alloc_gatt(dev);
+		if (gatt)
+			break;
+
+		/*
+		 * Probably contigmalloc failure. Try reducing the
+		 * aperture so that the gatt size reduces.
+		 */
+		if (AGP_SET_APERTURE(dev, AGP_GET_APERTURE(dev) / 2))
+			return ENOMEM;
+	}
+	sc->gatt = gatt;
+
+	/* Install the gatt. */
+	WRITE4(AGP_AMD751_ATTBASE, gatt->ag_physical);
+	
+	/* Enable synchronisation between host and agp. */
+	pci_write_config(dev, AGP_AMD751_MODECTRL, 0x80, 1);
+
+	/* Enable the TLB and flush */
+	WRITE2(AGP_AMD751_STATUS,
+	       READ2(AGP_AMD751_STATUS) | AGP_AMD751_STATUS_GCE);
+	AGP_FLUSH_TLB(dev);
+
+	return agp_generic_attach(dev);
+}
+
+static int
+agp_amd_detach(device_t dev)
+{
+	struct agp_amd_softc *sc = device_get_softc(dev);
+
+	/* Disable the TLB.. */
+	WRITE2(AGP_AMD751_STATUS,
+	       READ2(AGP_AMD751_STATUS) & ~AGP_AMD751_STATUS_GCE);
+	
+	/* Disable host-agp sync */
+	pci_write_config(dev, AGP_AMD751_MODECTRL, 0x00, 1);
+	
+	/* Clear the GATT base */
+	WRITE4(AGP_AMD751_ATTBASE, 0);
+
+	/* Put the aperture back the way it started. */
+	AGP_SET_APERTURE(dev, sc->initial_aperture);
+
+	agp_free_gatt(sc->gatt);
+	return 0;
+}
+
+static u_int32_t
+agp_amd_get_aperture(device_t dev)
+{
+	int vas;
+
+	/*
+	 * The aperture size is equal to 32M<<vas.
+	 */
+	vas = (pci_read_config(dev, AGP_AMD751_APCTRL, 1) & 0x06) >> 1;
+	return (32*1024*1024) << vas;
+}
+
+static int
+agp_amd_set_aperture(device_t dev, u_int32_t aperture)
+{
+	int vas;
+
+	/*
+	 * Check for a power of two and make sure its within the
+	 * programmable range.
+	 */
+	if (aperture & (aperture - 1)
+	    || aperture < 32*1024*1024
+	    || aperture > 2U*1024*1024*1024)
+		return EINVAL;
+
+	vas = ffs(aperture / 32*1024*1024) - 1;
+	
+	pci_write_config(dev, AGP_AMD751_APCTRL,
+			 ((pci_read_config(dev, AGP_AMD751_APCTRL, 1) & ~0x06)
+			  | vas << 1), 1);
+
+	return 0;
+}
+
+static int
+agp_amd_bind_page(device_t dev, int offset, vm_offset_t physical)
+{
+	struct agp_amd_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = physical | 1;
+	return 0;
+}
+
+static int
+agp_amd_unbind_page(device_t dev, int offset)
+{
+	struct agp_amd_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = 0;
+	return 0;
+}
+
+static void
+agp_amd_flush_tlb(device_t dev)
+{
+	struct agp_amd_softc *sc = device_get_softc(dev);
+
+	/* Set the cache invalidate bit and wait for the chipset to clear */
+	WRITE4(AGP_AMD751_TLBCTRL, 1);
+	do {
+		DELAY(1);
+	} while (READ4(AGP_AMD751_TLBCTRL));
+}
+
+static device_method_t agp_amd_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		agp_amd_probe),
+	DEVMETHOD(device_attach,	agp_amd_attach),
+	DEVMETHOD(device_detach,	agp_amd_detach),
+	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
+	DEVMETHOD(device_suspend,	bus_generic_suspend),
+	DEVMETHOD(device_resume,	bus_generic_resume),
+
+	/* AGP interface */
+	DEVMETHOD(agp_get_aperture,	agp_amd_get_aperture),
+	DEVMETHOD(agp_set_aperture,	agp_amd_set_aperture),
+	DEVMETHOD(agp_bind_page,	agp_amd_bind_page),
+	DEVMETHOD(agp_unbind_page,	agp_amd_unbind_page),
+	DEVMETHOD(agp_flush_tlb,	agp_amd_flush_tlb),
+	DEVMETHOD(agp_enable,		agp_generic_enable),
+	DEVMETHOD(agp_alloc_memory,	agp_generic_alloc_memory),
+	DEVMETHOD(agp_free_memory,	agp_generic_free_memory),
+	DEVMETHOD(agp_bind_memory,	agp_generic_bind_memory),
+	DEVMETHOD(agp_unbind_memory,	agp_generic_unbind_memory),
+
+	{ 0, 0 }
+};
+
+static driver_t agp_amd_driver = {
+	"agp",
+	agp_amd_methods,
+	sizeof(struct agp_amd_softc),
+};
+
+static devclass_t agp_devclass;
+
+DRIVER_MODULE(agp_amd, pci, agp_amd_driver, agp_devclass, 0, 0);
diff --git a/sys/pci/agp_if.m b/sys/pci/agp_if.m
new file mode 100644
index 0000000..06f64d3
--- /dev/null
+++ b/sys/pci/agp_if.m
@@ -0,0 +1,134 @@
+#
+# Copyright (c) 2000 Doug Rabson
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+#
+# $FreeBSD$
+#
+
+#include <sys/bus.h>
+
+#
+# The AGP interface is used internally to the agp driver to isolate the
+# differences between various AGP chipsets into chipset mini drivers. It
+# should not be used outside the AGP driver. The kernel api for accessing
+# AGP functionality is described in <pci/agpvar,h>
+#
+INTERFACE agp;
+
+#
+# Return the current aperture size.
+#
+METHOD u_int32_t get_aperture {
+	device_t	dev;
+};
+
+#
+# Set the size of the aperture. Return EINVAL on error or 0 on success.
+#
+METHOD int set_aperture {
+	device_t	dev;
+	u_int32_t	aperture;
+};
+
+#
+# Bind a single page in the AGP aperture to a given physical address.
+# The offset is a byte offset within the aperture which must be
+# aligned to an AGP page boundary.
+#
+METHOD int bind_page {
+	device_t	dev;
+	vm_offset_t	offset;
+	vm_offset_t	physical;
+};
+
+#
+# Unbind a single page in the AGP aperture.
+#
+METHOD int unbind_page {
+	device_t	dev;
+	vm_offset_t	offset;
+};
+
+#
+# Flush the GATT TLB. This is used after a call to bind_page to
+# ensure that any mappings cached in the chipset are discarded.
+#
+METHOD void flush_tlb {
+	device_t	dev;
+};
+
+#
+# Enable the agp hardware with the relavent mode. The mode bits are
+# defined in <pci/agpreg.h>
+#
+METHOD int enable {
+	device_t	dev;
+	u_int32_t	mode;
+};
+
+#
+# Allocate memory of a given type. The type is a chipset-specific
+# code which is used by certain integrated agp graphics chips
+# (basically just the i810 for now) to access special features of
+# the chipset. An opaque handle representing the memory region is
+# returned and can be used as an argument to free_memory, bind_memory 
+# and unbind_memory.
+#
+# The size is specified in bytes but must be a multiple of the AGP
+# page size.
+#
+METHOD struct agp_memory * alloc_memory {
+	device_t	dev;
+	int		type;
+	vm_size_t	size;
+};
+
+#
+# Free a memory region previously allocated with alloc_memory. Return
+# EBUSY if the memory is bound.
+#
+METHOD int free_memory {
+	device_t	dev;
+	struct agp_memory *mem;
+};
+
+#
+# Bind a memory region to a specific byte offset within the chipset's
+# AGP aperture. This effectively defines a range of contiguous
+# physical address which alias the (possibly uncontiguous) pages in
+# the memory region.
+#
+METHOD int bind_memory {
+	device_t	dev;
+	struct agp_memory *mem;
+	vm_offset_t	offset;
+};
+
+#
+# Unbind a memory region bound with bind_memory.
+#
+METHOD int unbind_memory {
+	device_t	dev;
+	struct agp_memory *handle;
+};
diff --git a/sys/pci/agp_intel.c b/sys/pci/agp_intel.c
new file mode 100644
index 0000000..88d38ec
--- /dev/null
+++ b/sys/pci/agp_intel.c
@@ -0,0 +1,266 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#include "opt_bus.h"
+#include "opt_pci.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/kernel.h>
+#include <sys/bus.h>
+#include <sys/lock.h>
+
+#include <pci/pcivar.h>
+#include <pci/pcireg.h>
+#include <pci/agppriv.h>
+#include <pci/agpreg.h>
+
+#include <vm/vm.h>
+#include <vm/vm_object.h>
+#include <vm/pmap.h>
+
+struct agp_intel_softc {
+	struct agp_softc agp;
+	u_int32_t	initial_aperture; /* aperture size at startup */
+	struct agp_gatt *gatt;
+};
+
+static const char*
+agp_intel_match(device_t dev)
+{
+	if (pci_get_class(dev) != PCIC_BRIDGE
+	    || pci_get_subclass(dev) != PCIS_BRIDGE_HOST)
+		return NULL;
+
+	if (agp_find_caps(dev) == 0)
+		return NULL;
+
+	switch (pci_get_devid(dev)) {
+	/* Intel -- vendor 0x8086 */
+	case 0x71808086:
+		return ("Intel 82443LX (440 LX) host to PCI bridge");
+
+	case 0x71908086:
+		return ("Intel 82443BX (440 BX) host to PCI bridge");
+
+ 	case 0x71a08086:
+ 		return ("Intel 82443GX host to PCI bridge");
+
+ 	case 0x71a18086:
+ 		return ("Intel 82443GX host to AGP bridge");
+	};
+
+	if (pci_get_vendor(dev) == 0x8086)
+		return ("Intel Generic host to PCI bridge");
+
+	return NULL;
+}
+
+static int
+agp_intel_probe(device_t dev)
+{
+	const char *desc;
+
+	desc = agp_intel_match(dev);
+	if (desc) {
+		device_verbose(dev);
+		device_set_desc(dev, desc);
+		return 0;
+	}
+
+	return ENXIO;
+}
+
+static int
+agp_intel_attach(device_t dev)
+{
+	struct agp_intel_softc *sc = device_get_softc(dev);
+	struct agp_gatt *gatt;
+	int error;
+
+	error = agp_generic_attach(dev);
+	if (error)
+		return error;
+
+	sc->initial_aperture = AGP_GET_APERTURE(dev);
+
+	for (;;) {
+		gatt = agp_alloc_gatt(dev);
+		if (gatt)
+			break;
+
+		/*
+		 * Probably contigmalloc failure. Try reducing the
+		 * aperture so that the gatt size reduces.
+		 */
+		if (AGP_SET_APERTURE(dev, AGP_GET_APERTURE(dev) / 2)) {
+			agp_generic_detach(dev);
+			return ENOMEM;
+		}
+	}
+	sc->gatt = gatt;
+
+	/* Install the gatt. */
+	pci_write_config(dev, AGP_INTEL_ATTBASE, gatt->ag_physical, 4);
+	
+	/* Enable things, clear errors etc. */
+	pci_write_config(dev, AGP_INTEL_AGPCTRL, 0x2280, 4);
+	pci_write_config(dev, AGP_INTEL_NBXCFG,
+			 (pci_read_config(dev, AGP_INTEL_NBXCFG, 4)
+			  & ~(1 << 10)) | (1 << 9), 4);
+	pci_write_config(dev, AGP_INTEL_ERRSTS + 1, 7, 1);
+
+	return 0;
+}
+
+static int
+agp_intel_detach(device_t dev)
+{
+	struct agp_intel_softc *sc = device_get_softc(dev);
+	int error;
+
+	error = agp_generic_detach(dev);
+	if (error)
+		return error;
+
+	printf("%s: set NBXCFG to %x\n", __FUNCTION__,
+			 (pci_read_config(dev, AGP_INTEL_NBXCFG, 4)
+			  & ~(1 << 9)));
+	pci_write_config(dev, AGP_INTEL_NBXCFG,
+			 (pci_read_config(dev, AGP_INTEL_NBXCFG, 4)
+			  & ~(1 << 9)), 4);
+	pci_write_config(dev, AGP_INTEL_ATTBASE, 0, 4);
+	AGP_SET_APERTURE(dev, sc->initial_aperture);
+	agp_free_gatt(sc->gatt);
+
+	return 0;
+}
+
+static u_int32_t
+agp_intel_get_aperture(device_t dev)
+{
+	u_int32_t apsize;
+
+	apsize = pci_read_config(dev, AGP_INTEL_APSIZE, 1) & 0x1f;
+
+	/*
+	 * The size is determined by the number of low bits of
+	 * register APBASE which are forced to zero. The low 22 bits
+	 * are always forced to zero and each zero bit in the apsize
+	 * field just read forces the corresponding bit in the 27:22
+	 * to be zero. We calculate the aperture size accordingly.
+	 */
+	return (((apsize ^ 0x1f) << 22) | ((1 << 22) - 1)) + 1;
+}
+
+static int
+agp_intel_set_aperture(device_t dev, u_int32_t aperture)
+{
+	u_int32_t apsize;
+
+	/*
+	 * Reverse the magic from get_aperture.
+	 */
+	apsize = ((aperture - 1) >> 22) ^ 0x1f;
+
+	/*
+	 * Double check for sanity.
+	 */
+	if ((((apsize ^ 0x1f) << 22) | ((1 << 22) - 1)) + 1 != aperture)
+		return EINVAL;
+
+	pci_write_config(dev, AGP_INTEL_APSIZE, apsize, 1);
+
+	return 0;
+}
+
+static int
+agp_intel_bind_page(device_t dev, int offset, vm_offset_t physical)
+{
+	struct agp_intel_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = physical | 0x17;
+	return 0;
+}
+
+static int
+agp_intel_unbind_page(device_t dev, int offset)
+{
+	struct agp_intel_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = 0;
+	return 0;
+}
+
+static void
+agp_intel_flush_tlb(device_t dev)
+{
+	pci_write_config(dev, AGP_INTEL_AGPCTRL, 0x2200, 4);
+	pci_write_config(dev, AGP_INTEL_AGPCTRL, 0x2280, 4);
+}
+
+static device_method_t agp_intel_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		agp_intel_probe),
+	DEVMETHOD(device_attach,	agp_intel_attach),
+	DEVMETHOD(device_detach,	agp_intel_detach),
+	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
+	DEVMETHOD(device_suspend,	bus_generic_suspend),
+	DEVMETHOD(device_resume,	bus_generic_resume),
+
+	/* AGP interface */
+	DEVMETHOD(agp_get_aperture,	agp_intel_get_aperture),
+	DEVMETHOD(agp_set_aperture,	agp_intel_set_aperture),
+	DEVMETHOD(agp_bind_page,	agp_intel_bind_page),
+	DEVMETHOD(agp_unbind_page,	agp_intel_unbind_page),
+	DEVMETHOD(agp_flush_tlb,	agp_intel_flush_tlb),
+	DEVMETHOD(agp_enable,		agp_generic_enable),
+	DEVMETHOD(agp_alloc_memory,	agp_generic_alloc_memory),
+	DEVMETHOD(agp_free_memory,	agp_generic_free_memory),
+	DEVMETHOD(agp_bind_memory,	agp_generic_bind_memory),
+	DEVMETHOD(agp_unbind_memory,	agp_generic_unbind_memory),
+
+	{ 0, 0 }
+};
+
+static driver_t agp_intel_driver = {
+	"agp",
+	agp_intel_methods,
+	sizeof(struct agp_intel_softc),
+};
+
+static devclass_t agp_devclass;
+
+DRIVER_MODULE(agp_intel, pci, agp_intel_driver, agp_devclass, 0, 0);
diff --git a/sys/pci/agp_sis.c b/sys/pci/agp_sis.c
new file mode 100644
index 0000000..1f1a50b
--- /dev/null
+++ b/sys/pci/agp_sis.c
@@ -0,0 +1,256 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#include "opt_bus.h"
+#include "opt_pci.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/kernel.h>
+#include <sys/bus.h>
+#include <sys/lock.h>
+
+#include <pci/pcivar.h>
+#include <pci/pcireg.h>
+#include <pci/agppriv.h>
+#include <pci/agpreg.h>
+
+#include <vm/vm.h>
+#include <vm/vm_object.h>
+#include <vm/pmap.h>
+
+struct agp_sis_softc {
+	struct agp_softc agp;
+	u_int32_t	initial_aperture; /* aperture size at startup */
+	struct agp_gatt *gatt;
+};
+
+static const char*
+agp_sis_match(device_t dev)
+{
+	if (pci_get_class(dev) != PCIC_BRIDGE
+	    || pci_get_subclass(dev) != PCIS_BRIDGE_HOST)
+		return NULL;
+
+	if (agp_find_caps(dev) == 0)
+		return NULL;
+
+	switch (pci_get_devid(dev)) {
+	case 0x00011039:
+		return ("SiS 5591 host to AGP bridge");
+	};
+
+	if (pci_get_vendor(dev) == 0x1039)
+		return ("SIS Generic host to PCI bridge");
+
+	return NULL;
+}
+
+static int
+agp_sis_probe(device_t dev)
+{
+	const char *desc;
+
+	desc = agp_sis_match(dev);
+	if (desc) {
+		device_verbose(dev);
+		device_set_desc(dev, desc);
+		return 0;
+	}
+
+	return ENXIO;
+}
+
+static int
+agp_sis_attach(device_t dev)
+{
+	struct agp_sis_softc *sc = device_get_softc(dev);
+	struct agp_gatt *gatt;
+	int error;
+
+	error = agp_generic_attach(dev);
+	if (error)
+		return error;
+
+	sc->initial_aperture = AGP_GET_APERTURE(dev);
+
+	for (;;) {
+		gatt = agp_alloc_gatt(dev);
+		if (gatt)
+			break;
+
+		/*
+		 * Probably contigmalloc failure. Try reducing the
+		 * aperture so that the gatt size reduces.
+		 */
+		if (AGP_SET_APERTURE(dev, AGP_GET_APERTURE(dev) / 2)) {
+			agp_generic_detach(dev);
+			return ENOMEM;
+		}
+	}
+	sc->gatt = gatt;
+
+	/* Install the gatt. */
+	pci_write_config(dev, AGP_SIS_ATTBASE, gatt->ag_physical, 4);
+	
+	/* Enable the aperture. */
+	pci_write_config(dev, AGP_SIS_WINCTRL,
+			 pci_read_config(dev, AGP_SIS_WINCTRL, 1) | 3, 1);
+
+	/*
+	 * Enable the TLB and make it automatically invalidate entries
+	 * when the GATT is written.
+	 */
+	pci_write_config(dev, AGP_SIS_TLBCTRL, 0x05, 1);
+
+	return 0;
+}
+
+static int
+agp_sis_detach(device_t dev)
+{
+	struct agp_sis_softc *sc = device_get_softc(dev);
+	int error;
+
+	error = agp_generic_detach(dev);
+	if (error)
+		return error;
+
+	/* Disable the aperture.. */
+	pci_write_config(dev, AGP_SIS_WINCTRL,
+			 pci_read_config(dev, AGP_SIS_WINCTRL, 1) & ~3, 1);
+
+	/* and the TLB. */
+	pci_write_config(dev, AGP_SIS_TLBCTRL, 0, 1);
+
+	/* Put the aperture back the way it started. */
+	AGP_SET_APERTURE(dev, sc->initial_aperture);
+
+	agp_free_gatt(sc->gatt);
+	return 0;
+}
+
+static u_int32_t
+agp_sis_get_aperture(device_t dev)
+{
+	int gws;
+
+	/*
+	 * The aperture size is equal to 4M<<gws.
+	 */
+	gws = (pci_read_config(dev, AGP_SIS_WINCTRL, 1) & 0x70) >> 4;
+	return (4*1024*1024) << gws;
+}
+
+static int
+agp_sis_set_aperture(device_t dev, u_int32_t aperture)
+{
+	int gws;
+
+	/*
+	 * Check for a power of two and make sure its within the
+	 * programmable range.
+	 */
+	if (aperture & (aperture - 1)
+	    || aperture < 4*1024*1024
+	    || aperture > 256*1024*1024)
+		return EINVAL;
+
+	gws = ffs(aperture / 4*1024*1024) - 1;
+	
+	pci_write_config(dev, AGP_SIS_WINCTRL,
+			 ((pci_read_config(dev, AGP_SIS_WINCTRL, 1) & ~0x70)
+			  | gws << 4), 1);
+
+	return 0;
+}
+
+static int
+agp_sis_bind_page(device_t dev, int offset, vm_offset_t physical)
+{
+	struct agp_sis_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = physical;
+	return 0;
+}
+
+static int
+agp_sis_unbind_page(device_t dev, int offset)
+{
+	struct agp_sis_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = 0;
+	return 0;
+}
+
+static void
+agp_sis_flush_tlb(device_t dev)
+{
+	pci_write_config(dev, AGP_SIS_TLBFLUSH, 0x02, 1);
+}
+
+static device_method_t agp_sis_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		agp_sis_probe),
+	DEVMETHOD(device_attach,	agp_sis_attach),
+	DEVMETHOD(device_detach,	agp_sis_detach),
+	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
+	DEVMETHOD(device_suspend,	bus_generic_suspend),
+	DEVMETHOD(device_resume,	bus_generic_resume),
+
+	/* AGP interface */
+	DEVMETHOD(agp_get_aperture,	agp_sis_get_aperture),
+	DEVMETHOD(agp_set_aperture,	agp_sis_set_aperture),
+	DEVMETHOD(agp_bind_page,	agp_sis_bind_page),
+	DEVMETHOD(agp_unbind_page,	agp_sis_unbind_page),
+	DEVMETHOD(agp_flush_tlb,	agp_sis_flush_tlb),
+	DEVMETHOD(agp_enable,		agp_generic_enable),
+	DEVMETHOD(agp_alloc_memory,	agp_generic_alloc_memory),
+	DEVMETHOD(agp_free_memory,	agp_generic_free_memory),
+	DEVMETHOD(agp_bind_memory,	agp_generic_bind_memory),
+	DEVMETHOD(agp_unbind_memory,	agp_generic_unbind_memory),
+
+	{ 0, 0 }
+};
+
+static driver_t agp_sis_driver = {
+	"agp",
+	agp_sis_methods,
+	sizeof(struct agp_sis_softc),
+};
+
+static devclass_t agp_devclass;
+
+DRIVER_MODULE(agp_sis, pci, agp_sis_driver, agp_devclass, 0, 0);
diff --git a/sys/pci/agp_via.c b/sys/pci/agp_via.c
new file mode 100644
index 0000000..983348e
--- /dev/null
+++ b/sys/pci/agp_via.c
@@ -0,0 +1,253 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#include "opt_bus.h"
+#include "opt_pci.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/kernel.h>
+#include <sys/bus.h>
+#include <sys/lock.h>
+
+#include <pci/pcivar.h>
+#include <pci/pcireg.h>
+#include <pci/agppriv.h>
+#include <pci/agpreg.h>
+
+#include <vm/vm.h>
+#include <vm/vm_object.h>
+#include <vm/pmap.h>
+
+struct agp_via_softc {
+	struct agp_softc agp;
+	u_int32_t	initial_aperture; /* aperture size at startup */
+	struct agp_gatt *gatt;
+};
+
+static const char*
+agp_via_match(device_t dev)
+{
+	if (pci_get_class(dev) != PCIC_BRIDGE
+	    || pci_get_subclass(dev) != PCIS_BRIDGE_HOST)
+		return NULL;
+
+	if (agp_find_caps(dev) == 0)
+		return NULL;
+
+	switch (pci_get_devid(dev)) {
+	case 0x05011106:
+		return ("VIA 8501 (Apollo MVP4) host to PCI bridge");
+	case 0x05971106:
+		return ("VIA 82C597 (Apollo VP3) host to PCI bridge");
+	case 0x05981106:
+		return ("VIA 82C598 (Apollo MVP3) host to PCI bridge");
+	case 0x06911106:
+		return ("VIA 82C691 (Apollo Pro) host to PCI bridge");
+	};
+
+	if (pci_get_vendor(dev) == 0x1106)
+		return ("VIA Generic host to PCI bridge");
+
+	return NULL;
+}
+
+static int
+agp_via_probe(device_t dev)
+{
+	const char *desc;
+
+	desc = agp_via_match(dev);
+	if (desc) {
+		device_verbose(dev);
+		device_set_desc(dev, desc);
+		return 0;
+	}
+
+	return ENXIO;
+}
+
+static int
+agp_via_attach(device_t dev)
+{
+	struct agp_via_softc *sc = device_get_softc(dev);
+	struct agp_gatt *gatt;
+	int error;
+
+	error = agp_generic_attach(dev);
+	if (error)
+		return error;
+
+	sc->initial_aperture = AGP_GET_APERTURE(dev);
+
+	for (;;) {
+		gatt = agp_alloc_gatt(dev);
+		if (gatt)
+			break;
+
+		/*
+		 * Probably contigmalloc failure. Try reducing the
+		 * aperture so that the gatt size reduces.
+		 */
+		if (AGP_SET_APERTURE(dev, AGP_GET_APERTURE(dev) / 2)) {
+			agp_generic_detach(dev);
+			return ENOMEM;
+		}
+	}
+	sc->gatt = gatt;
+
+	/* Install the gatt. */
+	pci_write_config(dev, AGP_VIA_ATTBASE, gatt->ag_physical | 3, 4);
+	
+	/* Enable the aperture. */
+	pci_write_config(dev, AGP_VIA_GARTCTRL, 0x0f, 4);
+
+	return 0;
+}
+
+static int
+agp_via_detach(device_t dev)
+{
+	struct agp_via_softc *sc = device_get_softc(dev);
+	int error;
+
+	error = agp_generic_detach(dev);
+	if (error)
+		return error;
+
+	pci_write_config(dev, AGP_VIA_GARTCTRL, 0, 4);
+	pci_write_config(dev, AGP_VIA_ATTBASE, 0, 4);
+	AGP_SET_APERTURE(dev, sc->initial_aperture);
+	agp_free_gatt(sc->gatt);
+
+	return 0;
+}
+
+static u_int32_t
+agp_via_get_aperture(device_t dev)
+{
+	u_int32_t apsize;
+
+	apsize = pci_read_config(dev, AGP_VIA_APSIZE, 1) & 0x1f;
+
+	/*
+	 * The size is determined by the number of low bits of
+	 * register APBASE which are forced to zero. The low 20 bits
+	 * are always forced to zero and each zero bit in the apsize
+	 * field just read forces the corresponding bit in the 27:20
+	 * to be zero. We calculate the aperture size accordingly.
+	 */
+	return (((apsize ^ 0xff) << 20) | ((1 << 20) - 1)) + 1;
+}
+
+static int
+agp_via_set_aperture(device_t dev, u_int32_t aperture)
+{
+	u_int32_t apsize;
+
+	/*
+	 * Reverse the magic from get_aperture.
+	 */
+	apsize = ((aperture - 1) >> 20) ^ 0xff;
+
+	/*
+	 * Double check for sanity.
+	 */
+	if ((((apsize ^ 0xff) << 20) | ((1 << 20) - 1)) + 1 != aperture)
+		return EINVAL;
+
+	pci_write_config(dev, AGP_VIA_APSIZE, apsize, 1);
+
+	return 0;
+}
+
+static int
+agp_via_bind_page(device_t dev, int offset, vm_offset_t physical)
+{
+	struct agp_via_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = physical;
+	return 0;
+}
+
+static int
+agp_via_unbind_page(device_t dev, int offset)
+{
+	struct agp_via_softc *sc = device_get_softc(dev);
+
+	if (offset < 0 || offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
+		return EINVAL;
+
+	sc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = 0;
+	return 0;
+}
+
+static void
+agp_via_flush_tlb(device_t dev)
+{
+	pci_write_config(dev, AGP_VIA_GARTCTRL, 0x8f, 4);
+	pci_write_config(dev, AGP_VIA_GARTCTRL, 0x0f, 4);
+}
+
+static device_method_t agp_via_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		agp_via_probe),
+	DEVMETHOD(device_attach,	agp_via_attach),
+	DEVMETHOD(device_detach,	agp_via_detach),
+	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
+	DEVMETHOD(device_suspend,	bus_generic_suspend),
+	DEVMETHOD(device_resume,	bus_generic_resume),
+
+	/* AGP interface */
+	DEVMETHOD(agp_get_aperture,	agp_via_get_aperture),
+	DEVMETHOD(agp_set_aperture,	agp_via_set_aperture),
+	DEVMETHOD(agp_bind_page,	agp_via_bind_page),
+	DEVMETHOD(agp_unbind_page,	agp_via_unbind_page),
+	DEVMETHOD(agp_flush_tlb,	agp_via_flush_tlb),
+	DEVMETHOD(agp_enable,		agp_generic_enable),
+	DEVMETHOD(agp_alloc_memory,	agp_generic_alloc_memory),
+	DEVMETHOD(agp_free_memory,	agp_generic_free_memory),
+	DEVMETHOD(agp_bind_memory,	agp_generic_bind_memory),
+	DEVMETHOD(agp_unbind_memory,	agp_generic_unbind_memory),
+
+	{ 0, 0 }
+};
+
+static driver_t agp_via_driver = {
+	"agp",
+	agp_via_methods,
+	sizeof(struct agp_via_softc),
+};
+
+static devclass_t agp_devclass;
+
+DRIVER_MODULE(agp_via, pci, agp_via_driver, agp_devclass, 0, 0);
diff --git a/sys/pci/agppriv.h b/sys/pci/agppriv.h
new file mode 100644
index 0000000..427e68b
--- /dev/null
+++ b/sys/pci/agppriv.h
@@ -0,0 +1,103 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#ifndef _PCI_AGPPRIV_H_
+#define _PCI_AGPPRIV_H_
+
+/*
+ * This file *must not* be included by code outside the agp driver itself.
+ */
+
+#include <sys/agpio.h>
+#include <pci/agpvar.h>
+
+#define AGP_DEBUGxx
+
+#ifdef AGP_DEBUG
+#define AGP_DPF(x...) do {			\
+    printf("agp: ");				\
+    printf(##x);				\
+} while (0)
+#else
+#define AGP_DPF(x...) do {} while (0)
+#endif
+
+#include "agp_if.h"
+
+/*
+ * Data structure to describe an AGP memory allocation.
+ */
+TAILQ_HEAD(agp_memory_list, agp_memory);
+struct agp_memory {
+	TAILQ_ENTRY(agp_memory) am_link;	/* wiring for the tailq */
+	int		am_id;			/* unique id for block */
+	vm_size_t	am_size;		/* number of bytes allocated */
+	struct vm_object *am_obj;		/* VM object owning pages */
+	vm_offset_t	am_physical;		/* bogus hack for i810 */
+	vm_offset_t	am_offset;		/* page offset if bound */
+	int		am_is_bound;		/* non-zero if bound */
+};
+
+/*
+ * All chipset drivers must have this at the start of their softc.
+ */
+struct agp_softc {
+	struct resource	        *as_aperture;	/* location of aperture */
+	u_int32_t		as_maxmem;	/* allocation upper bound */
+	u_int32_t		as_allocated;	/* amount allocated */
+	enum agp_acquire_state	as_state;
+	struct agp_memory_list	as_memory;	/* list of allocated memory */
+	int			as_nextid;	/* next memory block id */
+	int			as_isopen;	/* user device is open */
+	dev_t			as_devnode;	/* from make_dev */
+	struct lock		as_lock;	/* lock for access to GATT */
+};
+
+struct agp_gatt {
+	u_int32_t	ag_entries;
+	u_int32_t      *ag_virtual;
+	vm_offset_t	ag_physical;
+};
+
+u_int8_t		agp_find_caps(device_t dev);
+struct agp_gatt	       *agp_alloc_gatt(device_t dev);
+void		        agp_free_gatt(struct agp_gatt *gatt);
+int			agp_generic_attach(device_t dev);
+int			agp_generic_detach(device_t dev);
+int			agp_generic_enable(device_t dev, u_int32_t mode);
+struct agp_memory      *agp_generic_alloc_memory(device_t dev, int type,
+						 vm_size_t size);
+int			agp_generic_free_memory(device_t dev,
+						struct agp_memory *mem);
+int			agp_generic_bind_memory(device_t dev,
+						struct agp_memory *mem,
+						vm_offset_t offset);
+int			agp_generic_unbind_memory(device_t dev,
+						  struct agp_memory *mem);
+
+#endif /* !_PCI_AGPPRIV_H_ */
diff --git a/sys/pci/agpreg.h b/sys/pci/agpreg.h
new file mode 100644
index 0000000..0539325
--- /dev/null
+++ b/sys/pci/agpreg.h
@@ -0,0 +1,109 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#ifndef _PCI_AGPREG_H_
+#define _PCI_AGPREG_H_
+
+/*
+ * Offsets for various AGP configuration registers.
+ */
+#define AGP_APBASE		0x10
+#define AGP_CAPPTR		0x34
+
+/*
+ * Offsets from the AGP Capability pointer.
+ */
+#define AGP_CAPID		0x0
+#define AGP_CAPID_GET_MAJOR(x)		(((x) & 0x00f00000U) >> 20)
+#define AGP_CAPID_GET_MINOR(x)		(((x) & 0x000f0000U) >> 16)
+#define AGP_CAPID_GET_NEXT_PTR(x)	(((x) & 0x0000ff00U) >> 8)
+#define AGP_CAPID_GET_CAP_ID(x)		(((x) & 0x000000ffU) >> 0)
+
+#define AGP_STATUS		0x4
+#define AGP_COMMAND		0x8
+
+/*
+ * Config offsets for Intel AGP chipsets.
+ */
+#define AGP_INTEL_NBXCFG	0x50
+#define AGP_INTEL_ERRSTS	0x91
+#define AGP_INTEL_AGPCTRL	0xb0
+#define AGP_INTEL_APSIZE	0xb4
+#define AGP_INTEL_ATTBASE	0xb8
+
+/*
+ * Config offsets for VIA AGP chipsets.
+ */
+#define AGP_VIA_GARTCTRL	0x80
+#define AGP_VIA_APSIZE		0x84
+#define AGP_VIA_ATTBASE		0x88
+
+/*
+ * Config offsets for SiS AGP chipsets.
+ */
+#define AGP_SIS_ATTBASE		0x90
+#define AGP_SIS_WINCTRL		0x94
+#define AGP_SIS_TLBCTRL		0x97
+#define AGP_SIS_TLBFLUSH	0x98
+
+/*
+ * Config offsets for Ali AGP chipsets.
+ */
+#define AGP_ALI_AGPCTRL		0xb8
+#define AGP_ALI_ATTBASE		0xbc
+#define AGP_ALI_TLBCTRL		0xc0
+
+/*
+ * Config offsets for the AMD 751 chipset.
+ */
+#define AGP_AMD751_REGISTERS	0x14
+#define AGP_AMD751_APCTRL	0xac
+#define AGP_AMD751_MODECTRL	0xb0
+
+/*
+ * Memory mapped register offsets for AMD 751 chipset.
+ */
+#define AGP_AMD751_CAPS		0x00
+#define AGP_AMD751_CAPS_EHI		0x0800
+#define AGP_AMD751_CAPS_P2P		0x0400
+#define AGP_AMD751_CAPS_MPC		0x0200
+#define AGP_AMD751_CAPS_VBE		0x0100
+#define AGP_AMD751_CAPS_REV		0x00ff
+#define AGP_AMD751_STATUS	0x02
+#define AGP_AMD751_STATUS_P2PS		0x0800
+#define AGP_AMD751_STATUS_GCS		0x0400
+#define AGP_AMD751_STATUS_MPS		0x0200
+#define AGP_AMD751_STATUS_VBES		0x0100
+#define AGP_AMD751_STATUS_P2PE		0x0008
+#define AGP_AMD751_STATUS_GCE		0x0004
+#define AGP_AMD751_STATUS_VBEE		0x0001
+#define AGP_AMD751_ATTBASE	0x04
+#define AGP_AMD751_TLBCTRL	0x0c
+
+
+#endif /* !_PCI_AGPREG_H_ */
diff --git a/sys/pci/agpvar.h b/sys/pci/agpvar.h
new file mode 100644
index 0000000..df3112b
--- /dev/null
+++ b/sys/pci/agpvar.h
@@ -0,0 +1,125 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#ifndef _PCI_AGPVAR_H_
+#define _PCI_AGPVAR_H_
+
+/*
+ * The AGP chipset can be acquired by user or kernel code. If the
+ * chipset has already been acquired, it cannot be acquired by another 
+ * user until the previous user has released it.
+ */
+enum agp_acquire_state {
+	AGP_ACQUIRE_FREE,
+	AGP_ACQUIRE_USER,
+	AGP_ACQUIRE_KERNEL
+};
+
+/*
+ * This structure is used to query the state of the AGP system.
+ */
+struct agp_info {
+	u_int32_t	ai_mode;
+	vm_offset_t	ai_aperture_base;
+	vm_size_t	ai_aperture_size;
+	vm_size_t	ai_memory_allowed;
+	vm_size_t	ai_memory_used;
+	u_int32_t	ai_devid;
+};
+
+struct agp_memory_info {
+	vm_size_t	ami_size;	/* size in bytes */
+	vm_offset_t	ami_physical;	/* bogus hack for i810 */
+	vm_offset_t	ami_offset;	/* page offset if bound */
+	int		ami_is_bound;	/* non-zero if bound */
+};
+
+/*
+ * Find the AGP device and return it.
+ */
+device_t agp_find_device(void);
+
+/*
+ * Return the current owner of the AGP chipset.
+ */
+enum agp_acquire_state agp_state(device_t dev);
+
+/*
+ * Query the state of the AGP system.
+ */
+void agp_get_info(device_t dev, struct agp_info *info);
+
+/*
+ * Acquire the AGP chipset for use by the kernel. Returns EBUSY if the
+ * AGP chipset is already acquired by another user. 
+ */
+int agp_acquire(device_t dev);
+
+/*
+ * Release the AGP chipset.
+ */
+int agp_release(device_t dev);
+
+/*
+ * Enable the agp hardware with the relavent mode. The mode bits are
+ * defined in <pci/agpreg.h>
+ */
+int agp_enable(device_t dev, u_int32_t mode);
+
+/*
+ * Allocate physical memory suitable for mapping into the AGP
+ * aperture.  The value returned is an opaque handle which can be
+ * passed to agp_bind(), agp_unbind() or agp_deallocate().
+ */
+void *agp_alloc_memory(device_t dev, int type, vm_size_t bytes);
+
+/*
+ * Free memory which was allocated with agp_allocate().
+ */
+void agp_free_memory(device_t dev, void *handle);
+
+/*
+ * Bind memory allocated with agp_allocate() at a given offset within
+ * the AGP aperture. Returns EINVAL if the memory is already bound or
+ * the offset is not at an AGP page boundary.
+ */
+int agp_bind_memory(device_t dev, void *handle, vm_offset_t offset);
+
+/*
+ * Unbind memory from the AGP aperture. Returns EINVAL if the memory
+ * is not bound.
+ */
+int agp_unbind_memory(device_t dev, void *handle);
+
+/*
+ * Retrieve information about a memory block allocated with
+ * agp_alloc_memory().
+ */
+void agp_memory_info(device_t dev, void *handle, struct agp_memory_info *mi);
+
+#endif /* !_PCI_AGPVAR_H_ */
diff --git a/sys/sys/agpio.h b/sys/sys/agpio.h
new file mode 100644
index 0000000..ebdc352
--- /dev/null
+++ b/sys/sys/agpio.h
@@ -0,0 +1,128 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#ifndef _SYS_AGPIO_H_
+#define _SYS_AGPIO_H_
+
+/*
+ * The AGP gatt uses 4k pages irrespective of the host page size.
+ */
+#define AGP_PAGE_SIZE		4096
+#define AGP_PAGE_SHIFT		12
+
+/*
+ * Macros to manipulate AGP mode words.
+ */
+#define AGP_MODE_GET_RQ(x)		(((x) & 0xff000000U) >> 24)
+#define AGP_MODE_GET_SBA(x)		(((x) & 0x00000200U) >> 9)
+#define AGP_MODE_GET_AGP(x)		(((x) & 0x00000100U) >> 8)
+#define AGP_MODE_GET_4G(x)		(((x) & 0x00000020U) >> 5)
+#define AGP_MODE_GET_FW(x)		(((x) & 0x00000010U) >> 4)
+#define AGP_MODE_GET_RATE(x)		((x) & 0x00000003U)
+#define AGP_MODE_SET_RQ(x,v)		(((x) & ~0xff000000U) | ((v) << 24))
+#define AGP_MODE_SET_SBA(x,v)		(((x) & ~0x00000200U) | ((v) << 9))
+#define AGP_MODE_SET_AGP(x,v)		(((x) & ~0x00000100U) | ((v) << 8))
+#define AGP_MODE_SET_4G(x,v)		(((x) & ~0x00000020U) | ((v) << 5))
+#define AGP_MODE_SET_FW(x,v)		(((x) & ~0x00000010U) | ((v) << 4))
+#define AGP_MODE_SET_RATE(x,v)		(((x) & ~0x00000003U) | (v))
+#define AGP_MODE_RATE_1x		0x00000001
+#define AGP_MODE_RATE_2x		0x00000002
+#define AGP_MODE_RATE_4x		0x00000004
+
+#define AGPIOC_BASE       'A'
+#define AGPIOC_INFO       _IOR (AGPIOC_BASE, 0, agp_info)
+#define AGPIOC_ACQUIRE    _IO  (AGPIOC_BASE, 1)
+#define AGPIOC_RELEASE    _IO  (AGPIOC_BASE, 2)
+#define AGPIOC_SETUP      _IOW (AGPIOC_BASE, 3, agp_setup)
+#if 0
+#define AGPIOC_RESERVE    _IOW (AGPIOC_BASE, 4, agp_region)
+#define AGPIOC_PROTECT    _IOW (AGPIOC_BASE, 5, agp_region)
+#endif
+#define AGPIOC_ALLOCATE   _IOWR(AGPIOC_BASE, 6, agp_allocate)
+#define AGPIOC_DEALLOCATE _IOW (AGPIOC_BASE, 7, int)
+#define AGPIOC_BIND       _IOW (AGPIOC_BASE, 8, agp_bind)
+#define AGPIOC_UNBIND     _IOW (AGPIOC_BASE, 9, agp_unbind)
+
+typedef struct _agp_version {
+	u_int16_t major;
+	u_int16_t minor;
+} agp_version;
+
+typedef struct _agp_info {
+	agp_version version;	/* version of the driver        */
+	u_int32_t bridge_id;	/* bridge vendor/device         */
+	u_int32_t agp_mode;	/* mode info of bridge          */
+	off_t aper_base;	/* base of aperture             */
+	size_t aper_size;	/* size of aperture             */
+	size_t pg_total;	/* max pages (swap + system)    */
+	size_t pg_system;	/* max pages (system)           */
+	size_t pg_used;		/* current pages used           */
+} agp_info;
+
+typedef struct _agp_setup {
+	u_int32_t agp_mode;		/* mode info of bridge          */
+} agp_setup;
+
+#if 0
+/*
+ * The "prot" down below needs still a "sleep" flag somehow ...
+ */
+typedef struct _agp_segment {
+	off_t pg_start;		/* starting page to populate    */
+	size_t pg_count;	/* number of pages              */
+	int prot;		/* prot flags for mmap          */
+} agp_segment;
+
+typedef struct _agp_region {
+	pid_t pid;		/* pid of process               */
+	size_t seg_count;	/* number of segments           */
+	struct _agp_segment *seg_list;
+} agp_region;
+#endif
+
+typedef struct _agp_allocate {
+	int key;		/* tag of allocation            */
+	size_t pg_count;	/* number of pages              */
+	u_int32_t type;		/* 0 == normal, other devspec   */
+   	u_int32_t physical;     /* device specific (some devices  
+				 * need a phys address of the     
+				 * actual page behind the gatt    
+				 * table)                        */
+} agp_allocate;
+
+typedef struct _agp_bind {
+	int key;		/* tag of allocation            */
+	off_t pg_start;		/* starting page to populate    */
+} agp_bind;
+
+typedef struct _agp_unbind {
+	int key;		/* tag of allocation            */
+	u_int32_t priority;	/* priority for paging out      */
+} agp_unbind;
+
+#endif /* !_SYS_AGPIO_H_ */