/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2000 Doug Rabson
 * Copyright (c) 2000 Ruslan Ermilov
 * Copyright (c) 2011 The FreeBSD Foundation
 * All rights reserved.
 *
 * Portions of this software were developed by Konstantin Belousov
 * under sponsorship from the FreeBSD Foundation.
 *
 * 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.
 */

/*
 * Fixes for 830/845G support: David Dawes <dawes@xfree86.org>
 * 852GM/855GM/865G support added by David Dawes <dawes@xfree86.org>
 *
 * This is generic Intel GTT handling code, morphed from the AGP
 * bridge code.
 */

#include <sys/cdefs.h>
#if 0
#define KTR_AGP_I810    KTR_DEV
#else
#define KTR_AGP_I810    0
#endif

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/ktr.h>
#include <sys/module.h>
#include <sys/bus.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/rwlock.h>

#include <dev/agp/agppriv.h>
#include <dev/agp/agpreg.h>
#include <dev/agp/agp_i810.h>
#include <dev/pci/pcivar.h>
#include <dev/pci/pcireg.h>
#include <dev/pci/pci_private.h>

#include <vm/vm.h>
#include <vm/vm_extern.h>
#include <vm/vm_kern.h>
#include <vm/vm_param.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pageout.h>
#include <vm/pmap.h>

#include <machine/bus.h>
#include <machine/resource.h>
#include <machine/md_var.h>
#include <sys/rman.h>

MALLOC_DECLARE(M_AGP);

struct agp_i810_match;

static int agp_i810_check_active(device_t bridge_dev);
static int agp_i830_check_active(device_t bridge_dev);
static int agp_i915_check_active(device_t bridge_dev);

static void agp_82852_set_desc(device_t dev,
    const struct agp_i810_match *match);
static void agp_i810_set_desc(device_t dev, const struct agp_i810_match *match);

static void agp_i810_dump_regs(device_t dev);
static void agp_i830_dump_regs(device_t dev);
static void agp_i855_dump_regs(device_t dev);
static void agp_i915_dump_regs(device_t dev);
static void agp_i965_dump_regs(device_t dev);

static int agp_i810_get_stolen_size(device_t dev);
static int agp_i830_get_stolen_size(device_t dev);
static int agp_i915_get_stolen_size(device_t dev);

static int agp_i810_get_gtt_mappable_entries(device_t dev);
static int agp_i830_get_gtt_mappable_entries(device_t dev);
static int agp_i915_get_gtt_mappable_entries(device_t dev);

static int agp_i810_get_gtt_total_entries(device_t dev);
static int agp_i965_get_gtt_total_entries(device_t dev);
static int agp_gen5_get_gtt_total_entries(device_t dev);

static int agp_i810_install_gatt(device_t dev);
static int agp_i830_install_gatt(device_t dev);
static int agp_i965_install_gatt(device_t dev);
static int agp_g4x_install_gatt(device_t dev);

static void agp_i810_deinstall_gatt(device_t dev);
static void agp_i830_deinstall_gatt(device_t dev);

static void agp_i810_install_gtt_pte(device_t dev, u_int index,
    vm_offset_t physical, int flags);
static void agp_i830_install_gtt_pte(device_t dev, u_int index,
    vm_offset_t physical, int flags);
static void agp_i915_install_gtt_pte(device_t dev, u_int index,
    vm_offset_t physical, int flags);
static void agp_i965_install_gtt_pte(device_t dev, u_int index,
    vm_offset_t physical, int flags);
static void agp_g4x_install_gtt_pte(device_t dev, u_int index,
    vm_offset_t physical, int flags);

static void agp_i810_write_gtt(device_t dev, u_int index, uint32_t pte);
static void agp_i915_write_gtt(device_t dev, u_int index, uint32_t pte);
static void agp_i965_write_gtt(device_t dev, u_int index, uint32_t pte);
static void agp_g4x_write_gtt(device_t dev, u_int index, uint32_t pte);

static u_int32_t agp_i810_read_gtt_pte(device_t dev, u_int index);
static u_int32_t agp_i915_read_gtt_pte(device_t dev, u_int index);
static u_int32_t agp_i965_read_gtt_pte(device_t dev, u_int index);
static u_int32_t agp_g4x_read_gtt_pte(device_t dev, u_int index);

static vm_paddr_t agp_i810_read_gtt_pte_paddr(device_t dev, u_int index);
static vm_paddr_t agp_i915_read_gtt_pte_paddr(device_t dev, u_int index);

static int agp_i810_set_aperture(device_t dev, u_int32_t aperture);
static int agp_i830_set_aperture(device_t dev, u_int32_t aperture);
static int agp_i915_set_aperture(device_t dev, u_int32_t aperture);

static int agp_i810_chipset_flush_setup(device_t dev);
static int agp_i915_chipset_flush_setup(device_t dev);
static int agp_i965_chipset_flush_setup(device_t dev);

static void agp_i810_chipset_flush_teardown(device_t dev);
static void agp_i915_chipset_flush_teardown(device_t dev);
static void agp_i965_chipset_flush_teardown(device_t dev);

static void agp_i810_chipset_flush(device_t dev);
static void agp_i830_chipset_flush(device_t dev);
static void agp_i915_chipset_flush(device_t dev);

enum {
        CHIP_I810,      /* i810/i815 */
        CHIP_I830,      /* 830M/845G */
        CHIP_I855,      /* 852GM/855GM/865G */
        CHIP_I915,      /* 915G/915GM */
        CHIP_I965,      /* G965 */
        CHIP_G33,       /* G33/Q33/Q35 */
        CHIP_IGD,       /* Pineview */
        CHIP_G4X,       /* G45/Q45 */
};

/* The i810 through i855 have the registers at BAR 1, and the GATT gets
 * allocated by us.  The i915 has registers in BAR 0 and the GATT is at the
 * start of the stolen memory, and should only be accessed by the OS through
 * BAR 3.  The G965 has registers and GATT in the same BAR (0) -- first 512KB
 * is registers, second 512KB is GATT.
 */
static struct resource_spec agp_i810_res_spec[] = {
        { SYS_RES_MEMORY, AGP_I810_MMADR, RF_ACTIVE | RF_SHAREABLE },
        { -1, 0 }
};

static struct resource_spec agp_i915_res_spec[] = {
        { SYS_RES_MEMORY, AGP_I915_MMADR, RF_ACTIVE | RF_SHAREABLE },
        { SYS_RES_MEMORY, AGP_I915_GTTADR, RF_ACTIVE | RF_SHAREABLE },
        { -1, 0 }
};

static struct resource_spec agp_i965_res_spec[] = {
        { SYS_RES_MEMORY, AGP_I965_GTTMMADR, RF_ACTIVE | RF_SHAREABLE },
        { SYS_RES_MEMORY, AGP_I965_APBASE, RF_ACTIVE | RF_SHAREABLE },
        { -1, 0 }
};

struct agp_i810_softc {
        struct agp_softc agp;
        u_int32_t initial_aperture;     /* aperture size at startup */
        struct agp_gatt *gatt;
        u_int32_t dcache_size;          /* i810 only */
        u_int32_t stolen;               /* number of i830/845 gtt
                                           entries for stolen memory */
        u_int stolen_size;              /* BIOS-reserved graphics memory */
        u_int gtt_total_entries;        /* Total number of gtt ptes */
        u_int gtt_mappable_entries;     /* Number of gtt ptes mappable by CPU */
        device_t bdev;                  /* bridge device */
        void *argb_cursor;              /* contigmalloc area for ARGB cursor */
        struct resource *sc_res[2];
        const struct agp_i810_match *match;
        int sc_flush_page_rid;
        struct resource *sc_flush_page_res;
        void *sc_flush_page_vaddr;
        int sc_bios_allocated_flush_page;
};

static device_t intel_agp;

struct agp_i810_driver {
        int chiptype;
        int gen;
        int busdma_addr_mask_sz;
        struct resource_spec *res_spec;
        int (*check_active)(device_t);
        void (*set_desc)(device_t, const struct agp_i810_match *);
        void (*dump_regs)(device_t);
        int (*get_stolen_size)(device_t);
        int (*get_gtt_total_entries)(device_t);
        int (*get_gtt_mappable_entries)(device_t);
        int (*install_gatt)(device_t);
        void (*deinstall_gatt)(device_t);
        void (*write_gtt)(device_t, u_int, uint32_t);
        void (*install_gtt_pte)(device_t, u_int, vm_offset_t, int);
        u_int32_t (*read_gtt_pte)(device_t, u_int);
        vm_paddr_t (*read_gtt_pte_paddr)(device_t , u_int);
        int (*set_aperture)(device_t, u_int32_t);
        int (*chipset_flush_setup)(device_t);
        void (*chipset_flush_teardown)(device_t);
        void (*chipset_flush)(device_t);
};

static struct {
        struct intel_gtt base;
} intel_private;

static const struct agp_i810_driver agp_i810_i810_driver = {
        .chiptype = CHIP_I810,
        .gen = 1,
        .busdma_addr_mask_sz = 32,
        .res_spec = agp_i810_res_spec,
        .check_active = agp_i810_check_active,
        .set_desc = agp_i810_set_desc,
        .dump_regs = agp_i810_dump_regs,
        .get_stolen_size = agp_i810_get_stolen_size,
        .get_gtt_mappable_entries = agp_i810_get_gtt_mappable_entries,
        .get_gtt_total_entries = agp_i810_get_gtt_total_entries,
        .install_gatt = agp_i810_install_gatt,
        .deinstall_gatt = agp_i810_deinstall_gatt,
        .write_gtt = agp_i810_write_gtt,
        .install_gtt_pte = agp_i810_install_gtt_pte,
        .read_gtt_pte = agp_i810_read_gtt_pte,
        .read_gtt_pte_paddr = agp_i810_read_gtt_pte_paddr,
        .set_aperture = agp_i810_set_aperture,
        .chipset_flush_setup = agp_i810_chipset_flush_setup,
        .chipset_flush_teardown = agp_i810_chipset_flush_teardown,
        .chipset_flush = agp_i810_chipset_flush,
};

static const struct agp_i810_driver agp_i810_i815_driver = {
        .chiptype = CHIP_I810,
        .gen = 2,
        .busdma_addr_mask_sz = 32,
        .res_spec = agp_i810_res_spec,
        .check_active = agp_i810_check_active,
        .set_desc = agp_i810_set_desc,
        .dump_regs = agp_i810_dump_regs,
        .get_stolen_size = agp_i810_get_stolen_size,
        .get_gtt_mappable_entries = agp_i830_get_gtt_mappable_entries,
        .get_gtt_total_entries = agp_i810_get_gtt_total_entries,
        .install_gatt = agp_i810_install_gatt,
        .deinstall_gatt = agp_i810_deinstall_gatt,
        .write_gtt = agp_i810_write_gtt,
        .install_gtt_pte = agp_i810_install_gtt_pte,
        .read_gtt_pte = agp_i810_read_gtt_pte,
        .read_gtt_pte_paddr = agp_i810_read_gtt_pte_paddr,
        .set_aperture = agp_i810_set_aperture,
        .chipset_flush_setup = agp_i810_chipset_flush_setup,
        .chipset_flush_teardown = agp_i810_chipset_flush_teardown,
        .chipset_flush = agp_i830_chipset_flush,
};

static const struct agp_i810_driver agp_i810_i830_driver = {
        .chiptype = CHIP_I830,
        .gen = 2,
        .busdma_addr_mask_sz = 32,
        .res_spec = agp_i810_res_spec,
        .check_active = agp_i830_check_active,
        .set_desc = agp_i810_set_desc,
        .dump_regs = agp_i830_dump_regs,
        .get_stolen_size = agp_i830_get_stolen_size,
        .get_gtt_mappable_entries = agp_i830_get_gtt_mappable_entries,
        .get_gtt_total_entries = agp_i810_get_gtt_total_entries,
        .install_gatt = agp_i830_install_gatt,
        .deinstall_gatt = agp_i830_deinstall_gatt,
        .write_gtt = agp_i810_write_gtt,
        .install_gtt_pte = agp_i830_install_gtt_pte,
        .read_gtt_pte = agp_i810_read_gtt_pte,
        .read_gtt_pte_paddr = agp_i810_read_gtt_pte_paddr,
        .set_aperture = agp_i830_set_aperture,
        .chipset_flush_setup = agp_i810_chipset_flush_setup,
        .chipset_flush_teardown = agp_i810_chipset_flush_teardown,
        .chipset_flush = agp_i830_chipset_flush,
};

static const struct agp_i810_driver agp_i810_i855_driver = {
        .chiptype = CHIP_I855,
        .gen = 2,
        .busdma_addr_mask_sz = 32,
        .res_spec = agp_i810_res_spec,
        .check_active = agp_i830_check_active,
        .set_desc = agp_82852_set_desc,
        .dump_regs = agp_i855_dump_regs,
        .get_stolen_size = agp_i915_get_stolen_size,
        .get_gtt_mappable_entries = agp_i915_get_gtt_mappable_entries,
        .get_gtt_total_entries = agp_i810_get_gtt_total_entries,
        .install_gatt = agp_i830_install_gatt,
        .deinstall_gatt = agp_i830_deinstall_gatt,
        .write_gtt = agp_i810_write_gtt,
        .install_gtt_pte = agp_i830_install_gtt_pte,
        .read_gtt_pte = agp_i810_read_gtt_pte,
        .read_gtt_pte_paddr = agp_i810_read_gtt_pte_paddr,
        .set_aperture = agp_i830_set_aperture,
        .chipset_flush_setup = agp_i810_chipset_flush_setup,
        .chipset_flush_teardown = agp_i810_chipset_flush_teardown,
        .chipset_flush = agp_i830_chipset_flush,
};

static const struct agp_i810_driver agp_i810_i865_driver = {
        .chiptype = CHIP_I855,
        .gen = 2,
        .busdma_addr_mask_sz = 32,
        .res_spec = agp_i810_res_spec,
        .check_active = agp_i830_check_active,
        .set_desc = agp_i810_set_desc,
        .dump_regs = agp_i855_dump_regs,
        .get_stolen_size = agp_i915_get_stolen_size,
        .get_gtt_mappable_entries = agp_i915_get_gtt_mappable_entries,
        .get_gtt_total_entries = agp_i810_get_gtt_total_entries,
        .install_gatt = agp_i830_install_gatt,
        .deinstall_gatt = agp_i830_deinstall_gatt,
        .write_gtt = agp_i810_write_gtt,
        .install_gtt_pte = agp_i830_install_gtt_pte,
        .read_gtt_pte = agp_i810_read_gtt_pte,
        .read_gtt_pte_paddr = agp_i810_read_gtt_pte_paddr,
        .set_aperture = agp_i915_set_aperture,
        .chipset_flush_setup = agp_i810_chipset_flush_setup,
        .chipset_flush_teardown = agp_i810_chipset_flush_teardown,
        .chipset_flush = agp_i830_chipset_flush,
};

static const struct agp_i810_driver agp_i810_i915_driver = {
        .chiptype = CHIP_I915,
        .gen = 3,
        .busdma_addr_mask_sz = 32,
        .res_spec = agp_i915_res_spec,
        .check_active = agp_i915_check_active,
        .set_desc = agp_i810_set_desc,
        .dump_regs = agp_i915_dump_regs,
        .get_stolen_size = agp_i915_get_stolen_size,
        .get_gtt_mappable_entries = agp_i915_get_gtt_mappable_entries,
        .get_gtt_total_entries = agp_i810_get_gtt_total_entries,
        .install_gatt = agp_i830_install_gatt,
        .deinstall_gatt = agp_i830_deinstall_gatt,
        .write_gtt = agp_i915_write_gtt,
        .install_gtt_pte = agp_i915_install_gtt_pte,
        .read_gtt_pte = agp_i915_read_gtt_pte,
        .read_gtt_pte_paddr = agp_i915_read_gtt_pte_paddr,
        .set_aperture = agp_i915_set_aperture,
        .chipset_flush_setup = agp_i915_chipset_flush_setup,
        .chipset_flush_teardown = agp_i915_chipset_flush_teardown,
        .chipset_flush = agp_i915_chipset_flush,
};

static const struct agp_i810_driver agp_i810_g33_driver = {
        .chiptype = CHIP_G33,
        .gen = 3,
        .busdma_addr_mask_sz = 36,
        .res_spec = agp_i915_res_spec,
        .check_active = agp_i915_check_active,
        .set_desc = agp_i810_set_desc,
        .dump_regs = agp_i965_dump_regs,
        .get_stolen_size = agp_i915_get_stolen_size,
        .get_gtt_mappable_entries = agp_i915_get_gtt_mappable_entries,
        .get_gtt_total_entries = agp_i965_get_gtt_total_entries,
        .install_gatt = agp_i830_install_gatt,
        .deinstall_gatt = agp_i830_deinstall_gatt,
        .write_gtt = agp_i915_write_gtt,
        .install_gtt_pte = agp_i915_install_gtt_pte,
        .read_gtt_pte = agp_i915_read_gtt_pte,
        .read_gtt_pte_paddr = agp_i915_read_gtt_pte_paddr,
        .set_aperture = agp_i915_set_aperture,
        .chipset_flush_setup = agp_i965_chipset_flush_setup,
        .chipset_flush_teardown = agp_i965_chipset_flush_teardown,
        .chipset_flush = agp_i915_chipset_flush,
};

static const struct agp_i810_driver agp_i810_igd_driver = {
        .chiptype = CHIP_IGD,
        .gen = 3,
        .busdma_addr_mask_sz = 36,
        .res_spec = agp_i915_res_spec,
        .check_active = agp_i915_check_active,
        .set_desc = agp_i810_set_desc,
        .dump_regs = agp_i915_dump_regs,
        .get_stolen_size = agp_i915_get_stolen_size,
        .get_gtt_mappable_entries = agp_i915_get_gtt_mappable_entries,
        .get_gtt_total_entries = agp_i965_get_gtt_total_entries,
        .install_gatt = agp_i830_install_gatt,
        .deinstall_gatt = agp_i830_deinstall_gatt,
        .write_gtt = agp_i915_write_gtt,
        .install_gtt_pte = agp_i915_install_gtt_pte,
        .read_gtt_pte = agp_i915_read_gtt_pte,
        .read_gtt_pte_paddr = agp_i915_read_gtt_pte_paddr,
        .set_aperture = agp_i915_set_aperture,
        .chipset_flush_setup = agp_i965_chipset_flush_setup,
        .chipset_flush_teardown = agp_i965_chipset_flush_teardown,
        .chipset_flush = agp_i915_chipset_flush,
};

static const struct agp_i810_driver agp_i810_g965_driver = {
        .chiptype = CHIP_I965,
        .gen = 4,
        .busdma_addr_mask_sz = 36,
        .res_spec = agp_i965_res_spec,
        .check_active = agp_i915_check_active,
        .set_desc = agp_i810_set_desc,
        .dump_regs = agp_i965_dump_regs,
        .get_stolen_size = agp_i915_get_stolen_size,
        .get_gtt_mappable_entries = agp_i915_get_gtt_mappable_entries,
        .get_gtt_total_entries = agp_i965_get_gtt_total_entries,
        .install_gatt = agp_i965_install_gatt,
        .deinstall_gatt = agp_i830_deinstall_gatt,
        .write_gtt = agp_i965_write_gtt,
        .install_gtt_pte = agp_i965_install_gtt_pte,
        .read_gtt_pte = agp_i965_read_gtt_pte,
        .read_gtt_pte_paddr = agp_i915_read_gtt_pte_paddr,
        .set_aperture = agp_i915_set_aperture,
        .chipset_flush_setup = agp_i965_chipset_flush_setup,
        .chipset_flush_teardown = agp_i965_chipset_flush_teardown,
        .chipset_flush = agp_i915_chipset_flush,
};

static const struct agp_i810_driver agp_i810_g4x_driver = {
        .chiptype = CHIP_G4X,
        .gen = 5,
        .busdma_addr_mask_sz = 36,
        .res_spec = agp_i965_res_spec,
        .check_active = agp_i915_check_active,
        .set_desc = agp_i810_set_desc,
        .dump_regs = agp_i965_dump_regs,
        .get_stolen_size = agp_i915_get_stolen_size,
        .get_gtt_mappable_entries = agp_i915_get_gtt_mappable_entries,
        .get_gtt_total_entries = agp_gen5_get_gtt_total_entries,
        .install_gatt = agp_g4x_install_gatt,
        .deinstall_gatt = agp_i830_deinstall_gatt,
        .write_gtt = agp_g4x_write_gtt,
        .install_gtt_pte = agp_g4x_install_gtt_pte,
        .read_gtt_pte = agp_g4x_read_gtt_pte,
        .read_gtt_pte_paddr = agp_i915_read_gtt_pte_paddr,
        .set_aperture = agp_i915_set_aperture,
        .chipset_flush_setup = agp_i965_chipset_flush_setup,
        .chipset_flush_teardown = agp_i965_chipset_flush_teardown,
        .chipset_flush = agp_i915_chipset_flush,
};

/* For adding new devices, devid is the id of the graphics controller
 * (pci:0:2:0, for example).  The placeholder (usually at pci:0:2:1) for the
 * second head should never be added.  The bridge_offset is the offset to
 * subtract from devid to get the id of the hostb that the device is on.
 */
static const struct agp_i810_match {
        int devid;
        char *name;
        const struct agp_i810_driver *driver;
} agp_i810_matches[] = {
        {
                .devid = 0x71218086,
                .name = "Intel 82810 (i810 GMCH) SVGA controller",
                .driver = &agp_i810_i810_driver
        },
        {
                .devid = 0x71238086,
                .name = "Intel 82810-DC100 (i810-DC100 GMCH) SVGA controller",
                .driver = &agp_i810_i810_driver
        },
        {
                .devid = 0x71258086,
                .name = "Intel 82810E (i810E GMCH) SVGA controller",
                .driver = &agp_i810_i810_driver
        },
        {
                .devid = 0x11328086,
                .name = "Intel 82815 (i815 GMCH) SVGA controller",
                .driver = &agp_i810_i815_driver
        },
        {
                .devid = 0x35778086,
                .name = "Intel 82830M (830M GMCH) SVGA controller",
                .driver = &agp_i810_i830_driver
        },
        {
                .devid = 0x25628086,
                .name = "Intel 82845M (845M GMCH) SVGA controller",
                .driver = &agp_i810_i830_driver
        },
        {
                .devid = 0x35828086,
                .name = "Intel 82852/855GM SVGA controller",
                .driver = &agp_i810_i855_driver
        },
        {
                .devid = 0x25728086,
                .name = "Intel 82865G (865G GMCH) SVGA controller",
                .driver = &agp_i810_i865_driver
        },
        {
                .devid = 0x25828086,
                .name = "Intel 82915G (915G GMCH) SVGA controller",
                .driver = &agp_i810_i915_driver
        },
        {
                .devid = 0x258A8086,
                .name = "Intel E7221 SVGA controller",
                .driver = &agp_i810_i915_driver
        },
        {
                .devid = 0x25928086,
                .name = "Intel 82915GM (915GM GMCH) SVGA controller",
                .driver = &agp_i810_i915_driver
        },
        {
                .devid = 0x27728086,
                .name = "Intel 82945G (945G GMCH) SVGA controller",
                .driver = &agp_i810_i915_driver
        },
        {
                .devid = 0x27A28086,
                .name = "Intel 82945GM (945GM GMCH) SVGA controller",
                .driver = &agp_i810_i915_driver
        },
        {
                .devid = 0x27AE8086,
                .name = "Intel 945GME SVGA controller",
                .driver = &agp_i810_i915_driver
        },
        {
                .devid = 0x29728086,
                .name = "Intel 946GZ SVGA controller",
                .driver = &agp_i810_g965_driver
        },
        {
                .devid = 0x29828086,
                .name = "Intel G965 SVGA controller",
                .driver = &agp_i810_g965_driver
        },
        {
                .devid = 0x29928086,
                .name = "Intel Q965 SVGA controller",
                .driver = &agp_i810_g965_driver
        },
        {
                .devid = 0x29A28086,
                .name = "Intel G965 SVGA controller",
                .driver = &agp_i810_g965_driver
        },
        {
                .devid = 0x29B28086,
                .name = "Intel Q35 SVGA controller",
                .driver = &agp_i810_g33_driver
        },
        {
                .devid = 0x29C28086,
                .name = "Intel G33 SVGA controller",
                .driver = &agp_i810_g33_driver
        },
        {
                .devid = 0x29D28086,
                .name = "Intel Q33 SVGA controller",
                .driver = &agp_i810_g33_driver
        },
        {
                .devid = 0xA0018086,
                .name = "Intel Pineview SVGA controller",
                .driver = &agp_i810_igd_driver
        },
        {
                .devid = 0xA0118086,
                .name = "Intel Pineview (M) SVGA controller",
                .driver = &agp_i810_igd_driver
        },
        {
                .devid = 0x2A028086,
                .name = "Intel GM965 SVGA controller",
                .driver = &agp_i810_g965_driver
        },
        {
                .devid = 0x2A128086,
                .name = "Intel GME965 SVGA controller",
                .driver = &agp_i810_g965_driver
        },
        {
                .devid = 0x2A428086,
                .name = "Intel GM45 SVGA controller",
                .driver = &agp_i810_g4x_driver
        },
        {
                .devid = 0x2E028086,
                .name = "Intel Eaglelake SVGA controller",
                .driver = &agp_i810_g4x_driver
        },
        {
                .devid = 0x2E128086,
                .name = "Intel Q45 SVGA controller",
                .driver = &agp_i810_g4x_driver
        },
        {
                .devid = 0x2E228086,
                .name = "Intel G45 SVGA controller",
                .driver = &agp_i810_g4x_driver
        },
        {
                .devid = 0x2E328086,
                .name = "Intel G41 SVGA controller",
                .driver = &agp_i810_g4x_driver
        },
        {
                .devid = 0x00428086,
                .name = "Intel Ironlake (D) SVGA controller",
                .driver = &agp_i810_g4x_driver
        },
        {
                .devid = 0x00468086,
                .name = "Intel Ironlake (M) SVGA controller",
                .driver = &agp_i810_g4x_driver
        },
        {
                .devid = 0,
        }
};

static const struct agp_i810_match*
agp_i810_match(device_t dev)
{
        int i, devid;

        if (pci_get_class(dev) != PCIC_DISPLAY
            || (pci_get_subclass(dev) != PCIS_DISPLAY_VGA &&
            pci_get_subclass(dev) != PCIS_DISPLAY_OTHER))
                return (NULL);

        devid = pci_get_devid(dev);
        for (i = 0; agp_i810_matches[i].devid != 0; i++) {
                if (agp_i810_matches[i].devid == devid)
                        break;
        }
        if (agp_i810_matches[i].devid == 0)
                return (NULL);
        else
                return (&agp_i810_matches[i]);
}

/*
 * Find bridge device.
 */
static device_t
agp_i810_find_bridge(device_t dev)
{

        return (pci_find_dbsf(0, 0, 0, 0));
}

static void
agp_i810_identify(driver_t *driver, device_t parent)
{

        if (device_find_child(parent, "agp", DEVICE_UNIT_ANY) == NULL &&
            agp_i810_match(parent))
                device_add_child(parent, "agp", DEVICE_UNIT_ANY);
}

static int
agp_i810_check_active(device_t bridge_dev)
{
        u_int8_t smram;

        smram = pci_read_config(bridge_dev, AGP_I810_SMRAM, 1);
        if ((smram & AGP_I810_SMRAM_GMS) == AGP_I810_SMRAM_GMS_DISABLED)
                return (ENXIO);
        return (0);
}

static int
agp_i830_check_active(device_t bridge_dev)
{
        int gcc1;

        gcc1 = pci_read_config(bridge_dev, AGP_I830_GCC1, 1);
        if ((gcc1 & AGP_I830_GCC1_DEV2) == AGP_I830_GCC1_DEV2_DISABLED)
                return (ENXIO);
        return (0);
}

static int
agp_i915_check_active(device_t bridge_dev)
{
        int deven;

        deven = pci_read_config(bridge_dev, AGP_I915_DEVEN, 4);
        if ((deven & AGP_I915_DEVEN_D2F0) == AGP_I915_DEVEN_D2F0_DISABLED)
                return (ENXIO);
        return (0);
}

static void
agp_82852_set_desc(device_t dev, const struct agp_i810_match *match)
{

        switch (pci_read_config(dev, AGP_I85X_CAPID, 1)) {
        case AGP_I855_GME:
                device_set_desc(dev,
                    "Intel 82855GME (855GME GMCH) SVGA controller");
                break;
        case AGP_I855_GM:
                device_set_desc(dev,
                    "Intel 82855GM (855GM GMCH) SVGA controller");
                break;
        case AGP_I852_GME:
                device_set_desc(dev,
                    "Intel 82852GME (852GME GMCH) SVGA controller");
                break;
        case AGP_I852_GM:
                device_set_desc(dev,
                    "Intel 82852GM (852GM GMCH) SVGA controller");
                break;
        default:
                device_set_desc(dev,
                    "Intel 8285xM (85xGM GMCH) SVGA controller");
                break;
        }
}

static void
agp_i810_set_desc(device_t dev, const struct agp_i810_match *match)
{

        device_set_desc(dev, match->name);
}

static int
agp_i810_probe(device_t dev)
{
        device_t bdev;
        const struct agp_i810_match *match;
        int err;

        if (resource_disabled("agp", device_get_unit(dev)))
                return (ENXIO);
        match = agp_i810_match(dev);
        if (match == NULL)
                return (ENXIO);

        bdev = agp_i810_find_bridge(dev);
        if (bdev == NULL) {
                if (bootverbose)
                        printf("I810: can't find bridge device\n");
                return (ENXIO);
        }

        /*
         * checking whether internal graphics device has been activated.
         */
        err = match->driver->check_active(bdev);
        if (err != 0) {
                if (bootverbose)
                        printf("i810: disabled, not probing\n");
                return (err);
        }

        match->driver->set_desc(dev, match);
        return (BUS_PROBE_DEFAULT);
}

static void
agp_i810_dump_regs(device_t dev)
{
        struct agp_i810_softc *sc = device_get_softc(dev);

        device_printf(dev, "AGP_I810_PGTBL_CTL: %08x\n",
            bus_read_4(sc->sc_res[0], AGP_I810_PGTBL_CTL));
        device_printf(dev, "AGP_I810_MISCC: 0x%04x\n",
            pci_read_config(sc->bdev, AGP_I810_MISCC, 2));
}

static void
agp_i830_dump_regs(device_t dev)
{
        struct agp_i810_softc *sc = device_get_softc(dev);

        device_printf(dev, "AGP_I810_PGTBL_CTL: %08x\n",
            bus_read_4(sc->sc_res[0], AGP_I810_PGTBL_CTL));
        device_printf(dev, "AGP_I830_GCC1: 0x%02x\n",
            pci_read_config(sc->bdev, AGP_I830_GCC1, 1));
}

static void
agp_i855_dump_regs(device_t dev)
{
        struct agp_i810_softc *sc = device_get_softc(dev);

        device_printf(dev, "AGP_I810_PGTBL_CTL: %08x\n",
            bus_read_4(sc->sc_res[0], AGP_I810_PGTBL_CTL));
        device_printf(dev, "AGP_I855_GCC1: 0x%02x\n",
            pci_read_config(sc->bdev, AGP_I855_GCC1, 1));
}

static void
agp_i915_dump_regs(device_t dev)
{
        struct agp_i810_softc *sc = device_get_softc(dev);

        device_printf(dev, "AGP_I810_PGTBL_CTL: %08x\n",
            bus_read_4(sc->sc_res[0], AGP_I810_PGTBL_CTL));
        device_printf(dev, "AGP_I855_GCC1: 0x%02x\n",
            pci_read_config(sc->bdev, AGP_I855_GCC1, 1));
        device_printf(dev, "AGP_I915_MSAC: 0x%02x\n",
            pci_read_config(sc->bdev, AGP_I915_MSAC, 1));
}

static void
agp_i965_dump_regs(device_t dev)
{
        struct agp_i810_softc *sc = device_get_softc(dev);

        device_printf(dev, "AGP_I965_PGTBL_CTL2: %08x\n",
            bus_read_4(sc->sc_res[0], AGP_I965_PGTBL_CTL2));
        device_printf(dev, "AGP_I855_GCC1: 0x%02x\n",
            pci_read_config(sc->bdev, AGP_I855_GCC1, 1));
        device_printf(dev, "AGP_I965_MSAC: 0x%02x\n",
            pci_read_config(sc->bdev, AGP_I965_MSAC, 1));
}

static int
agp_i810_get_stolen_size(device_t dev)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(dev);
        sc->stolen = 0;
        sc->stolen_size = 0;
        return (0);
}

static int
agp_i830_get_stolen_size(device_t dev)
{
        struct agp_i810_softc *sc;
        unsigned int gcc1;

        sc = device_get_softc(dev);

        gcc1 = pci_read_config(sc->bdev, AGP_I830_GCC1, 1);
        switch (gcc1 & AGP_I830_GCC1_GMS) {
        case AGP_I830_GCC1_GMS_STOLEN_512:
                sc->stolen = (512 - 132) * 1024 / 4096;
                sc->stolen_size = 512 * 1024;
                break;
        case AGP_I830_GCC1_GMS_STOLEN_1024:
                sc->stolen = (1024 - 132) * 1024 / 4096;
                sc->stolen_size = 1024 * 1024;
                break;
        case AGP_I830_GCC1_GMS_STOLEN_8192:
                sc->stolen = (8192 - 132) * 1024 / 4096;
                sc->stolen_size = 8192 * 1024;
                break;
        default:
                sc->stolen = 0;
                device_printf(dev,
                    "unknown memory configuration, disabling (GCC1 %x)\n",
                    gcc1);
                return (EINVAL);
        }
        return (0);
}

static int
agp_i915_get_stolen_size(device_t dev)
{
        struct agp_i810_softc *sc;
        unsigned int gcc1, stolen, gtt_size;

        sc = device_get_softc(dev);

        /*
         * Stolen memory is set up at the beginning of the aperture by
         * the BIOS, consisting of the GATT followed by 4kb for the
         * BIOS display.
         */
        switch (sc->match->driver->chiptype) {
        case CHIP_I855:
                gtt_size = 128;
                break;
        case CHIP_I915:
                gtt_size = 256;
                break;
        case CHIP_I965:
                switch (bus_read_4(sc->sc_res[0], AGP_I810_PGTBL_CTL) &
                        AGP_I810_PGTBL_SIZE_MASK) {
                case AGP_I810_PGTBL_SIZE_128KB:
                        gtt_size = 128;
                        break;
                case AGP_I810_PGTBL_SIZE_256KB:
                        gtt_size = 256;
                        break;
                case AGP_I810_PGTBL_SIZE_512KB:
                        gtt_size = 512;
                        break;
                case AGP_I965_PGTBL_SIZE_1MB:
                        gtt_size = 1024;
                        break;
                case AGP_I965_PGTBL_SIZE_2MB:
                        gtt_size = 2048;
                        break;
                case AGP_I965_PGTBL_SIZE_1_5MB:
                        gtt_size = 1024 + 512;
                        break;
                default:
                        device_printf(dev, "Bad PGTBL size\n");
                        return (EINVAL);
                }
                break;
        case CHIP_G33:
                gcc1 = pci_read_config(sc->bdev, AGP_I855_GCC1, 2);
                switch (gcc1 & AGP_G33_MGGC_GGMS_MASK) {
                case AGP_G33_MGGC_GGMS_SIZE_1M:
                        gtt_size = 1024;
                        break;
                case AGP_G33_MGGC_GGMS_SIZE_2M:
                        gtt_size = 2048;
                        break;
                default:
                        device_printf(dev, "Bad PGTBL size\n");
                        return (EINVAL);
                }
                break;
        case CHIP_IGD:
        case CHIP_G4X:
                gtt_size = 0;
                break;
        default:
                device_printf(dev, "Bad chiptype\n");
                return (EINVAL);
        }

        /* GCC1 is called MGGC on i915+ */
        gcc1 = pci_read_config(sc->bdev, AGP_I855_GCC1, 1);
        switch (gcc1 & AGP_I855_GCC1_GMS) {
        case AGP_I855_GCC1_GMS_STOLEN_1M:
                stolen = 1024;
                break;
        case AGP_I855_GCC1_GMS_STOLEN_4M:
                stolen = 4 * 1024;
                break;
        case AGP_I855_GCC1_GMS_STOLEN_8M:
                stolen = 8 * 1024;
                break;
        case AGP_I855_GCC1_GMS_STOLEN_16M:
                stolen = 16 * 1024;
                break;
        case AGP_I855_GCC1_GMS_STOLEN_32M:
                stolen = 32 * 1024;
                break;
        case AGP_I915_GCC1_GMS_STOLEN_48M:
                stolen = sc->match->driver->gen > 2 ? 48 * 1024 : 0;
                break;
        case AGP_I915_GCC1_GMS_STOLEN_64M:
                stolen = sc->match->driver->gen > 2 ? 64 * 1024 : 0;
                break;
        case AGP_G33_GCC1_GMS_STOLEN_128M:
                stolen = sc->match->driver->gen > 2 ? 128 * 1024 : 0;
                break;
        case AGP_G33_GCC1_GMS_STOLEN_256M:
                stolen = sc->match->driver->gen > 2 ? 256 * 1024 : 0;
                break;
        case AGP_G4X_GCC1_GMS_STOLEN_96M:
                if (sc->match->driver->chiptype == CHIP_I965 ||
                    sc->match->driver->chiptype == CHIP_G4X)
                        stolen = 96 * 1024;
                else
                        stolen = 0;
                break;
        case AGP_G4X_GCC1_GMS_STOLEN_160M:
                if (sc->match->driver->chiptype == CHIP_I965 ||
                    sc->match->driver->chiptype == CHIP_G4X)
                        stolen = 160 * 1024;
                else
                        stolen = 0;
                break;
        case AGP_G4X_GCC1_GMS_STOLEN_224M:
                if (sc->match->driver->chiptype == CHIP_I965 ||
                    sc->match->driver->chiptype == CHIP_G4X)
                        stolen = 224 * 1024;
                else
                        stolen = 0;
                break;
        case AGP_G4X_GCC1_GMS_STOLEN_352M:
                if (sc->match->driver->chiptype == CHIP_I965 ||
                    sc->match->driver->chiptype == CHIP_G4X)
                        stolen = 352 * 1024;
                else
                        stolen = 0;
                break;
        default:
                device_printf(dev,
                    "unknown memory configuration, disabling (GCC1 %x)\n",
                    gcc1);
                return (EINVAL);
        }

        gtt_size += 4;
        sc->stolen_size = stolen * 1024;
        sc->stolen = (stolen - gtt_size) * 1024 / 4096;

        return (0);
}

static int
agp_i810_get_gtt_mappable_entries(device_t dev)
{
        struct agp_i810_softc *sc;
        uint32_t ap;
        uint16_t miscc;

        sc = device_get_softc(dev);
        miscc = pci_read_config(sc->bdev, AGP_I810_MISCC, 2);
        if ((miscc & AGP_I810_MISCC_WINSIZE) == AGP_I810_MISCC_WINSIZE_32)
                ap = 32;
        else
                ap = 64;
        sc->gtt_mappable_entries = (ap * 1024 * 1024) >> AGP_PAGE_SHIFT;
        return (0);
}

static int
agp_i830_get_gtt_mappable_entries(device_t dev)
{
        struct agp_i810_softc *sc;
        uint32_t ap;
        uint16_t gmch_ctl;

        sc = device_get_softc(dev);
        gmch_ctl = pci_read_config(sc->bdev, AGP_I830_GCC1, 2);
        if ((gmch_ctl & AGP_I830_GCC1_GMASIZE) == AGP_I830_GCC1_GMASIZE_64)
                ap = 64;
        else
                ap = 128;
        sc->gtt_mappable_entries = (ap * 1024 * 1024) >> AGP_PAGE_SHIFT;
        return (0);
}

static int
agp_i915_get_gtt_mappable_entries(device_t dev)
{
        struct agp_i810_softc *sc;
        uint32_t ap;

        sc = device_get_softc(dev);
        ap = AGP_GET_APERTURE(dev);
        sc->gtt_mappable_entries = ap >> AGP_PAGE_SHIFT;
        return (0);
}

static int
agp_i810_get_gtt_total_entries(device_t dev)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(dev);
        sc->gtt_total_entries = sc->gtt_mappable_entries;
        return (0);
}

static int
agp_i965_get_gtt_total_entries(device_t dev)
{
        struct agp_i810_softc *sc;
        uint32_t pgetbl_ctl;
        int error;

        sc = device_get_softc(dev);
        error = 0;
        pgetbl_ctl = bus_read_4(sc->sc_res[0], AGP_I810_PGTBL_CTL);
        switch (pgetbl_ctl & AGP_I810_PGTBL_SIZE_MASK) {
        case AGP_I810_PGTBL_SIZE_128KB:
                sc->gtt_total_entries = 128 * 1024 / 4;
                break;
        case AGP_I810_PGTBL_SIZE_256KB:
                sc->gtt_total_entries = 256 * 1024 / 4;
                break;
        case AGP_I810_PGTBL_SIZE_512KB:
                sc->gtt_total_entries = 512 * 1024 / 4;
                break;
        /* GTT pagetable sizes bigger than 512KB are not possible on G33! */
        case AGP_I810_PGTBL_SIZE_1MB:
                sc->gtt_total_entries = 1024 * 1024 / 4;
                break;
        case AGP_I810_PGTBL_SIZE_2MB:
                sc->gtt_total_entries = 2 * 1024 * 1024 / 4;
                break;
        case AGP_I810_PGTBL_SIZE_1_5MB:
                sc->gtt_total_entries = (1024 + 512) * 1024 / 4;
                break;
        default:
                device_printf(dev, "Unknown page table size\n");
                error = ENXIO;
        }
        return (error);
}

static void
agp_gen5_adjust_pgtbl_size(device_t dev, uint32_t sz)
{
        struct agp_i810_softc *sc;
        uint32_t pgetbl_ctl, pgetbl_ctl2;

        sc = device_get_softc(dev);

        /* Disable per-process page table. */
        pgetbl_ctl2 = bus_read_4(sc->sc_res[0], AGP_I965_PGTBL_CTL2);
        pgetbl_ctl2 &= ~AGP_I810_PGTBL_ENABLED;
        bus_write_4(sc->sc_res[0], AGP_I965_PGTBL_CTL2, pgetbl_ctl2);

        /* Write the new ggtt size. */
        pgetbl_ctl = bus_read_4(sc->sc_res[0], AGP_I810_PGTBL_CTL);
        pgetbl_ctl &= ~AGP_I810_PGTBL_SIZE_MASK;
        pgetbl_ctl |= sz;
        bus_write_4(sc->sc_res[0], AGP_I810_PGTBL_CTL, pgetbl_ctl);
}

static int
agp_gen5_get_gtt_total_entries(device_t dev)
{
        struct agp_i810_softc *sc;
        uint16_t gcc1;

        sc = device_get_softc(dev);

        gcc1 = pci_read_config(sc->bdev, AGP_I830_GCC1, 2);
        switch (gcc1 & AGP_G4x_GCC1_SIZE_MASK) {
        case AGP_G4x_GCC1_SIZE_1M:
        case AGP_G4x_GCC1_SIZE_VT_1M:
                agp_gen5_adjust_pgtbl_size(dev, AGP_I810_PGTBL_SIZE_1MB);
                break;
        case AGP_G4x_GCC1_SIZE_VT_1_5M:
                agp_gen5_adjust_pgtbl_size(dev, AGP_I810_PGTBL_SIZE_1_5MB);
                break;
        case AGP_G4x_GCC1_SIZE_2M:
        case AGP_G4x_GCC1_SIZE_VT_2M:
                agp_gen5_adjust_pgtbl_size(dev, AGP_I810_PGTBL_SIZE_2MB);
                break;
        default:
                device_printf(dev, "Unknown page table size\n");
                return (ENXIO);
        }

        return (agp_i965_get_gtt_total_entries(dev));
}

static int
agp_i810_install_gatt(device_t dev)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(dev);

        /* Some i810s have on-chip memory called dcache. */
        if ((bus_read_1(sc->sc_res[0], AGP_I810_DRT) & AGP_I810_DRT_POPULATED)
            != 0)
                sc->dcache_size = 4 * 1024 * 1024;
        else
                sc->dcache_size = 0;

        /* According to the specs the gatt on the i810 must be 64k. */
        sc->gatt->ag_virtual = kmem_alloc_contig(64 * 1024, M_NOWAIT |
            M_ZERO, 0, ~0, PAGE_SIZE, 0, VM_MEMATTR_WRITE_COMBINING);
        if (sc->gatt->ag_virtual == NULL) {
                if (bootverbose)
                        device_printf(dev, "contiguous allocation failed\n");
                return (ENOMEM);
        }

        sc->gatt->ag_physical = vtophys((vm_offset_t)sc->gatt->ag_virtual);
        /* Install the GATT. */
        bus_write_4(sc->sc_res[0], AGP_I810_PGTBL_CTL,
            sc->gatt->ag_physical | 1);
        return (0);
}

static void
agp_i830_install_gatt_init(struct agp_i810_softc *sc)
{
        uint32_t pgtblctl;

        /*
         * The i830 automatically initializes the 128k gatt on boot.
         * GATT address is already in there, make sure it's enabled.
         */
        pgtblctl = bus_read_4(sc->sc_res[0], AGP_I810_PGTBL_CTL);
        pgtblctl |= 1;
        bus_write_4(sc->sc_res[0], AGP_I810_PGTBL_CTL, pgtblctl);

        sc->gatt->ag_physical = pgtblctl & ~1;
}

static int
agp_i830_install_gatt(device_t dev)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(dev);
        agp_i830_install_gatt_init(sc);
        return (0);
}

static int
agp_gen4_install_gatt(device_t dev, const vm_size_t gtt_offset)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(dev);
        pmap_change_attr((vm_offset_t)rman_get_virtual(sc->sc_res[0]) +
            gtt_offset, rman_get_size(sc->sc_res[0]) - gtt_offset,
            VM_MEMATTR_WRITE_COMBINING);
        agp_i830_install_gatt_init(sc);
        return (0);
}

static int
agp_i965_install_gatt(device_t dev)
{

        return (agp_gen4_install_gatt(dev, 512 * 1024));
}

static int
agp_g4x_install_gatt(device_t dev)
{

        return (agp_gen4_install_gatt(dev, 2 * 1024 * 1024));
}

static int
agp_i810_attach(device_t dev)
{
        struct agp_i810_softc *sc;
        int error;

        sc = device_get_softc(dev);
        sc->bdev = agp_i810_find_bridge(dev);
        if (sc->bdev == NULL)
                return (ENOENT);

        sc->match = agp_i810_match(dev);

        agp_set_aperture_resource(dev, sc->match->driver->gen <= 2 ?
            AGP_APBASE : AGP_I915_GMADR);
        error = agp_generic_attach(dev);
        if (error)
                return (error);

        if (ptoa((vm_paddr_t)Maxmem) >
            (1ULL << sc->match->driver->busdma_addr_mask_sz) - 1) {
                device_printf(dev, "agp_i810 does not support physical "
                    "memory above %ju.\n", (uintmax_t)(1ULL <<
                    sc->match->driver->busdma_addr_mask_sz) - 1);
                return (ENOENT);
        }

        if (bus_alloc_resources(dev, sc->match->driver->res_spec, sc->sc_res)) {
                agp_generic_detach(dev);
                return (ENODEV);
        }

        sc->initial_aperture = AGP_GET_APERTURE(dev);
        sc->gatt = malloc(sizeof(struct agp_gatt), M_AGP, M_WAITOK);
        sc->gatt->ag_entries = AGP_GET_APERTURE(dev) >> AGP_PAGE_SHIFT;

        if ((error = sc->match->driver->get_stolen_size(dev)) != 0 ||
            (error = sc->match->driver->install_gatt(dev)) != 0 ||
            (error = sc->match->driver->get_gtt_mappable_entries(dev)) != 0 ||
            (error = sc->match->driver->get_gtt_total_entries(dev)) != 0 ||
            (error = sc->match->driver->chipset_flush_setup(dev)) != 0) {
                bus_release_resources(dev, sc->match->driver->res_spec,
                    sc->sc_res);
                free(sc->gatt, M_AGP);
                agp_generic_detach(dev);
                return (error);
        }

        intel_agp = dev;
        device_printf(dev, "aperture size is %dM",
            sc->initial_aperture / 1024 / 1024);
        if (sc->stolen > 0)
                printf(", detected %dk stolen memory\n", sc->stolen * 4);
        else
                printf("\n");
        if (bootverbose) {
                sc->match->driver->dump_regs(dev);
                device_printf(dev, "Mappable GTT entries: %d\n",
                    sc->gtt_mappable_entries);
                device_printf(dev, "Total GTT entries: %d\n",
                    sc->gtt_total_entries);
        }
        return (0);
}

static void
agp_i810_deinstall_gatt(device_t dev)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(dev);
        bus_write_4(sc->sc_res[0], AGP_I810_PGTBL_CTL, 0);
        kmem_free(sc->gatt->ag_virtual, 64 * 1024);
}

static void
agp_i830_deinstall_gatt(device_t dev)
{
        struct agp_i810_softc *sc;
        unsigned int pgtblctl;

        sc = device_get_softc(dev);
        pgtblctl = bus_read_4(sc->sc_res[0], AGP_I810_PGTBL_CTL);
        pgtblctl &= ~1;
        bus_write_4(sc->sc_res[0], AGP_I810_PGTBL_CTL, pgtblctl);
}

static int
agp_i810_detach(device_t dev)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(dev);
        agp_free_cdev(dev);

        /* Clear the GATT base. */
        sc->match->driver->deinstall_gatt(dev);

        sc->match->driver->chipset_flush_teardown(dev);

        /* Put the aperture back the way it started. */
        AGP_SET_APERTURE(dev, sc->initial_aperture);

        free(sc->gatt, M_AGP);
        bus_release_resources(dev, sc->match->driver->res_spec, sc->sc_res);
        agp_free_res(dev);

        return (0);
}

static int
agp_i810_resume(device_t dev)
{
        struct agp_i810_softc *sc;
        sc = device_get_softc(dev);

        AGP_SET_APERTURE(dev, sc->initial_aperture);

        /* Install the GATT. */
        bus_write_4(sc->sc_res[0], AGP_I810_PGTBL_CTL,
        sc->gatt->ag_physical | 1);

        return (bus_generic_resume(dev));
}

/**
 * Sets the PCI resource size of the aperture on i830-class and below chipsets,
 * while returning failure on later chipsets when an actual change is
 * requested.
 *
 * This whole function is likely bogus, as the kernel would probably need to
 * reconfigure the placement of the AGP aperture if a larger size is requested,
 * which doesn't happen currently.
 */
static int
agp_i810_set_aperture(device_t dev, u_int32_t aperture)
{
        struct agp_i810_softc *sc;
        u_int16_t miscc;

        sc = device_get_softc(dev);
        /*
         * Double check for sanity.
         */
        if (aperture != 32 * 1024 * 1024 && aperture != 64 * 1024 * 1024) {
                device_printf(dev, "bad aperture size %d\n", aperture);
                return (EINVAL);
        }

        miscc = pci_read_config(sc->bdev, AGP_I810_MISCC, 2);
        miscc &= ~AGP_I810_MISCC_WINSIZE;
        if (aperture == 32 * 1024 * 1024)
                miscc |= AGP_I810_MISCC_WINSIZE_32;
        else
                miscc |= AGP_I810_MISCC_WINSIZE_64;

        pci_write_config(sc->bdev, AGP_I810_MISCC, miscc, 2);
        return (0);
}

static int
agp_i830_set_aperture(device_t dev, u_int32_t aperture)
{
        struct agp_i810_softc *sc;
        u_int16_t gcc1;

        sc = device_get_softc(dev);

        if (aperture != 64 * 1024 * 1024 &&
            aperture != 128 * 1024 * 1024) {
                device_printf(dev, "bad aperture size %d\n", aperture);
                return (EINVAL);
        }
        gcc1 = pci_read_config(sc->bdev, AGP_I830_GCC1, 2);
        gcc1 &= ~AGP_I830_GCC1_GMASIZE;
        if (aperture == 64 * 1024 * 1024)
                gcc1 |= AGP_I830_GCC1_GMASIZE_64;
        else
                gcc1 |= AGP_I830_GCC1_GMASIZE_128;

        pci_write_config(sc->bdev, AGP_I830_GCC1, gcc1, 2);
        return (0);
}

static int
agp_i915_set_aperture(device_t dev, u_int32_t aperture)
{

        return (agp_generic_set_aperture(dev, aperture));
}

static int
agp_i810_method_set_aperture(device_t dev, u_int32_t aperture)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(dev);
        return (sc->match->driver->set_aperture(dev, aperture));
}

/**
 * Writes a GTT entry mapping the page at the given offset from the
 * beginning of the aperture to the given physical address.  Setup the
 * caching mode according to flags.
 *
 * For gen 1, 2 and 3, GTT start is located at AGP_I810_GTT offset
 * from corresponding BAR start. For gen 4, offset is 512KB +
 * AGP_I810_GTT, for gen 5 and 6 it is 2MB + AGP_I810_GTT.
 *
 * Also, the bits of the physical page address above 4GB needs to be
 * placed into bits 40-32 of PTE.
 */
static void
agp_i810_install_gtt_pte(device_t dev, u_int index, vm_offset_t physical,
    int flags)
{
        uint32_t pte;

        pte = (u_int32_t)physical | I810_PTE_VALID;
        if (flags == AGP_DCACHE_MEMORY)
                pte |= I810_PTE_LOCAL;
        else if (flags == AGP_USER_CACHED_MEMORY)
                pte |= I830_PTE_SYSTEM_CACHED;
        agp_i810_write_gtt(dev, index, pte);
}

static void
agp_i810_write_gtt(device_t dev, u_int index, uint32_t pte)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(dev);
        bus_write_4(sc->sc_res[0], AGP_I810_GTT + index * 4, pte);
        CTR2(KTR_AGP_I810, "810_pte %x %x", index, pte);
}

static void
agp_i830_install_gtt_pte(device_t dev, u_int index, vm_offset_t physical,
    int flags)
{
        uint32_t pte;

        pte = (u_int32_t)physical | I810_PTE_VALID;
        if (flags == AGP_USER_CACHED_MEMORY)
                pte |= I830_PTE_SYSTEM_CACHED;
        agp_i810_write_gtt(dev, index, pte);
}

static void
agp_i915_install_gtt_pte(device_t dev, u_int index, vm_offset_t physical,
    int flags)
{
        uint32_t pte;

        pte = (u_int32_t)physical | I810_PTE_VALID;
        if (flags == AGP_USER_CACHED_MEMORY)
                pte |= I830_PTE_SYSTEM_CACHED;
        pte |= (physical & 0x0000000f00000000ull) >> 28;
        agp_i915_write_gtt(dev, index, pte);
}

static void
agp_i915_write_gtt(device_t dev, u_int index, uint32_t pte)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(dev);
        bus_write_4(sc->sc_res[1], index * 4, pte);
        CTR2(KTR_AGP_I810, "915_pte %x %x", index, pte);
}

static void
agp_i965_install_gtt_pte(device_t dev, u_int index, vm_offset_t physical,
    int flags)
{
        uint32_t pte;

        pte = (u_int32_t)physical | I810_PTE_VALID;
        if (flags == AGP_USER_CACHED_MEMORY)
                pte |= I830_PTE_SYSTEM_CACHED;
        pte |= (physical & 0x0000000f00000000ull) >> 28;
        agp_i965_write_gtt(dev, index, pte);
}

static void
agp_i965_write_gtt(device_t dev, u_int index, uint32_t pte)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(dev);
        bus_write_4(sc->sc_res[0], index * 4 + (512 * 1024), pte);
        CTR2(KTR_AGP_I810, "965_pte %x %x", index, pte);
}

static void
agp_g4x_install_gtt_pte(device_t dev, u_int index, vm_offset_t physical,
    int flags)
{
        uint32_t pte;

        pte = (u_int32_t)physical | I810_PTE_VALID;
        if (flags == AGP_USER_CACHED_MEMORY)
                pte |= I830_PTE_SYSTEM_CACHED;
        pte |= (physical & 0x0000000f00000000ull) >> 28;
        agp_g4x_write_gtt(dev, index, pte);
}

static void
agp_g4x_write_gtt(device_t dev, u_int index, uint32_t pte)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(dev);
        bus_write_4(sc->sc_res[0], index * 4 + (2 * 1024 * 1024), pte);
        CTR2(KTR_AGP_I810, "g4x_pte %x %x", index, pte);
}

static int
agp_i810_bind_page(device_t dev, vm_offset_t offset, vm_offset_t physical)
{
        struct agp_i810_softc *sc = device_get_softc(dev);
        u_int index;

        if (offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT)) {
                device_printf(dev, "failed: offset is 0x%08jx, "
                    "shift is %d, entries is %d\n", (intmax_t)offset,
                    AGP_PAGE_SHIFT, sc->gatt->ag_entries);
                return (EINVAL);
        }
        index = offset >> AGP_PAGE_SHIFT;
        if (sc->stolen != 0 && index < sc->stolen) {
                device_printf(dev, "trying to bind into stolen memory\n");
                return (EINVAL);
        }
        sc->match->driver->install_gtt_pte(dev, index, physical, 0);
        return (0);
}

static int
agp_i810_unbind_page(device_t dev, vm_offset_t offset)
{
        struct agp_i810_softc *sc;
        u_int index;

        sc = device_get_softc(dev);
        if (offset >= (sc->gatt->ag_entries << AGP_PAGE_SHIFT))
                return (EINVAL);
        index = offset >> AGP_PAGE_SHIFT;
        if (sc->stolen != 0 && index < sc->stolen) {
                device_printf(dev, "trying to unbind from stolen memory\n");
                return (EINVAL);
        }
        sc->match->driver->install_gtt_pte(dev, index, 0, 0);
        return (0);
}

static u_int32_t
agp_i810_read_gtt_pte(device_t dev, u_int index)
{
        struct agp_i810_softc *sc;
        u_int32_t pte;

        sc = device_get_softc(dev);
        pte = bus_read_4(sc->sc_res[0], AGP_I810_GTT + index * 4);
        return (pte);
}

static u_int32_t
agp_i915_read_gtt_pte(device_t dev, u_int index)
{
        struct agp_i810_softc *sc;
        u_int32_t pte;

        sc = device_get_softc(dev);
        pte = bus_read_4(sc->sc_res[1], index * 4);
        return (pte);
}

static u_int32_t
agp_i965_read_gtt_pte(device_t dev, u_int index)
{
        struct agp_i810_softc *sc;
        u_int32_t pte;

        sc = device_get_softc(dev);
        pte = bus_read_4(sc->sc_res[0], index * 4 + (512 * 1024));
        return (pte);
}

static u_int32_t
agp_g4x_read_gtt_pte(device_t dev, u_int index)
{
        struct agp_i810_softc *sc;
        u_int32_t pte;

        sc = device_get_softc(dev);
        pte = bus_read_4(sc->sc_res[0], index * 4 + (2 * 1024 * 1024));
        return (pte);
}

static vm_paddr_t
agp_i810_read_gtt_pte_paddr(device_t dev, u_int index)
{
        struct agp_i810_softc *sc;
        u_int32_t pte;
        vm_paddr_t res;

        sc = device_get_softc(dev);
        pte = sc->match->driver->read_gtt_pte(dev, index);
        res = pte & ~PAGE_MASK;
        return (res);
}

static vm_paddr_t
agp_i915_read_gtt_pte_paddr(device_t dev, u_int index)
{
        struct agp_i810_softc *sc;
        u_int32_t pte;
        vm_paddr_t res;

        sc = device_get_softc(dev);
        pte = sc->match->driver->read_gtt_pte(dev, index);
        res = (pte & ~PAGE_MASK) | ((pte & 0xf0) << 28);
        return (res);
}

/*
 * Writing via memory mapped registers already flushes all TLBs.
 */
static void
agp_i810_flush_tlb(device_t dev)
{
}

static int
agp_i810_enable(device_t dev, u_int32_t mode)
{

        return (0);
}

static struct agp_memory *
agp_i810_alloc_memory(device_t dev, int type, vm_size_t size)
{
        struct agp_i810_softc *sc;
        struct agp_memory *mem;
        vm_page_t m;

        sc = device_get_softc(dev);

        if ((size & (AGP_PAGE_SIZE - 1)) != 0 ||
            sc->agp.as_allocated + size > sc->agp.as_maxmem)
                return (0);

        if (type == 1) {
                /*
                 * Mapping local DRAM into GATT.
                 */
                if (sc->match->driver->chiptype != CHIP_I810)
                        return (0);
                if (size != sc->dcache_size)
                        return (0);
        } else if (type == 2) {
                /*
                 * Type 2 is the contiguous physical memory type, that hands
                 * back a physical address.  This is used for cursors on i810.
                 * Hand back as many single pages with physical as the user
                 * wants, but only allow one larger allocation (ARGB cursor)
                 * for simplicity.
                 */
                if (size != AGP_PAGE_SIZE) {
                        if (sc->argb_cursor != NULL)
                                return (0);

                        /* Allocate memory for ARGB cursor, if we can. */
                        sc->argb_cursor = contigmalloc(size, M_AGP,
                           0, 0, ~0, PAGE_SIZE, 0);
                        if (sc->argb_cursor == NULL)
                                return (0);
                }
        }

        mem = malloc(sizeof *mem, M_AGP, M_WAITOK);
        mem->am_id = sc->agp.as_nextid++;
        mem->am_size = size;
        mem->am_type = type;
        if (type != 1 && (type != 2 || size == AGP_PAGE_SIZE))
                mem->am_obj = vm_object_allocate(OBJT_SWAP,
                    atop(round_page(size)));
        else
                mem->am_obj = 0;

        if (type == 2) {
                if (size == AGP_PAGE_SIZE) {
                        /*
                         * Allocate and wire down the page now so that we can
                         * get its physical address.
                         */
                        VM_OBJECT_WLOCK(mem->am_obj);
                        m = vm_page_grab(mem->am_obj, 0, VM_ALLOC_NOBUSY |
                            VM_ALLOC_WIRED | VM_ALLOC_ZERO);
                        VM_OBJECT_WUNLOCK(mem->am_obj);
                        mem->am_physical = VM_PAGE_TO_PHYS(m);
                } else {
                        /* Our allocation is already nicely wired down for us.
                         * Just grab the physical address.
                         */
                        mem->am_physical = vtophys(sc->argb_cursor);
                }
        } else
                mem->am_physical = 0;

        mem->am_offset = 0;
        mem->am_is_bound = 0;
        TAILQ_INSERT_TAIL(&sc->agp.as_memory, mem, am_link);
        sc->agp.as_allocated += size;

        return (mem);
}

static int
agp_i810_free_memory(device_t dev, struct agp_memory *mem)
{
        struct agp_i810_softc *sc;
        vm_page_t m;

        if (mem->am_is_bound)
                return (EBUSY);

        sc = device_get_softc(dev);

        if (mem->am_type == 2) {
                if (mem->am_size == AGP_PAGE_SIZE) {
                        /*
                         * Unwire the page which we wired in alloc_memory.
                         */
                        VM_OBJECT_WLOCK(mem->am_obj);
                        m = vm_page_lookup(mem->am_obj, 0);
                        vm_page_unwire(m, PQ_INACTIVE);
                        VM_OBJECT_WUNLOCK(mem->am_obj);
                } else {
                        free(sc->argb_cursor, M_AGP);
                        sc->argb_cursor = NULL;
                }
        }

        sc->agp.as_allocated -= mem->am_size;
        TAILQ_REMOVE(&sc->agp.as_memory, mem, am_link);
        if (mem->am_obj)
                vm_object_deallocate(mem->am_obj);
        free(mem, M_AGP);
        return (0);
}

static int
agp_i810_bind_memory(device_t dev, struct agp_memory *mem, vm_offset_t offset)
{
        struct agp_i810_softc *sc;
        vm_offset_t i;

        /* Do some sanity checks first. */
        if ((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);
        }

        sc = device_get_softc(dev);
        if (mem->am_type == 2 && mem->am_size != AGP_PAGE_SIZE) {
                mtx_lock(&sc->agp.as_lock);
                if (mem->am_is_bound) {
                        mtx_unlock(&sc->agp.as_lock);
                        return (EINVAL);
                }
                /* The memory's already wired down, just stick it in the GTT. */
                for (i = 0; i < mem->am_size; i += AGP_PAGE_SIZE) {
                        sc->match->driver->install_gtt_pte(dev, (offset + i) >>
                            AGP_PAGE_SHIFT, mem->am_physical + i, 0);
                }
                mem->am_offset = offset;
                mem->am_is_bound = 1;
                mtx_unlock(&sc->agp.as_lock);
                return (0);
        }

        if (mem->am_type != 1)
                return (agp_generic_bind_memory(dev, mem, offset));

        /*
         * Mapping local DRAM into GATT.
         */
        if (sc->match->driver->chiptype != CHIP_I810)
                return (EINVAL);
        for (i = 0; i < mem->am_size; i += AGP_PAGE_SIZE)
                bus_write_4(sc->sc_res[0],
                    AGP_I810_GTT + (i >> AGP_PAGE_SHIFT) * 4, i | 3);

        return (0);
}

static int
agp_i810_unbind_memory(device_t dev, struct agp_memory *mem)
{
        struct agp_i810_softc *sc;
        vm_offset_t i;

        sc = device_get_softc(dev);

        if (mem->am_type == 2 && mem->am_size != AGP_PAGE_SIZE) {
                mtx_lock(&sc->agp.as_lock);
                if (!mem->am_is_bound) {
                        mtx_unlock(&sc->agp.as_lock);
                        return (EINVAL);
                }

                for (i = 0; i < mem->am_size; i += AGP_PAGE_SIZE) {
                        sc->match->driver->install_gtt_pte(dev,
                            (mem->am_offset + i) >> AGP_PAGE_SHIFT, 0, 0);
                }
                mem->am_is_bound = 0;
                mtx_unlock(&sc->agp.as_lock);
                return (0);
        }

        if (mem->am_type != 1)
                return (agp_generic_unbind_memory(dev, mem));

        if (sc->match->driver->chiptype != CHIP_I810)
                return (EINVAL);
        for (i = 0; i < mem->am_size; i += AGP_PAGE_SIZE) {
                sc->match->driver->install_gtt_pte(dev, i >> AGP_PAGE_SHIFT,
                    0, 0);
        }
        return (0);
}

static device_method_t agp_i810_methods[] = {
        /* Device interface */
        DEVMETHOD(device_identify,      agp_i810_identify),
        DEVMETHOD(device_probe,         agp_i810_probe),
        DEVMETHOD(device_attach,        agp_i810_attach),
        DEVMETHOD(device_detach,        agp_i810_detach),
        DEVMETHOD(device_suspend,       bus_generic_suspend),
        DEVMETHOD(device_resume,        agp_i810_resume),

        /* AGP interface */
        DEVMETHOD(agp_get_aperture,     agp_generic_get_aperture),
        DEVMETHOD(agp_set_aperture,     agp_i810_method_set_aperture),
        DEVMETHOD(agp_bind_page,        agp_i810_bind_page),
        DEVMETHOD(agp_unbind_page,      agp_i810_unbind_page),
        DEVMETHOD(agp_flush_tlb,        agp_i810_flush_tlb),
        DEVMETHOD(agp_enable,           agp_i810_enable),
        DEVMETHOD(agp_alloc_memory,     agp_i810_alloc_memory),
        DEVMETHOD(agp_free_memory,      agp_i810_free_memory),
        DEVMETHOD(agp_bind_memory,      agp_i810_bind_memory),
        DEVMETHOD(agp_unbind_memory,    agp_i810_unbind_memory),
        DEVMETHOD(agp_chipset_flush,    agp_intel_gtt_chipset_flush),
        DEVMETHOD_END
};

static driver_t agp_i810_driver = {
        "agp",
        agp_i810_methods,
        sizeof(struct agp_i810_softc),
};

DRIVER_MODULE(agp_i810, vgapci, agp_i810_driver, 0, 0);
MODULE_DEPEND(agp_i810, agp, 1, 1, 1);
MODULE_DEPEND(agp_i810, pci, 1, 1, 1);

void
agp_intel_gtt_clear_range(device_t dev, u_int first_entry, u_int num_entries)
{
        struct agp_i810_softc *sc;
        u_int i;

        sc = device_get_softc(dev);
        for (i = 0; i < num_entries; i++)
                sc->match->driver->install_gtt_pte(dev, first_entry + i,
                    VM_PAGE_TO_PHYS(bogus_page), 0);
        sc->match->driver->read_gtt_pte(dev, first_entry + num_entries - 1);
}

void
agp_intel_gtt_insert_pages(device_t dev, u_int first_entry, u_int num_entries,
    vm_page_t *pages, u_int flags)
{
        struct agp_i810_softc *sc;
        u_int i;

        sc = device_get_softc(dev);
        for (i = 0; i < num_entries; i++) {
                MPASS(pages[i]->valid == VM_PAGE_BITS_ALL);
                MPASS(pages[i]->ref_count > 0);
                sc->match->driver->install_gtt_pte(dev, first_entry + i,
                    VM_PAGE_TO_PHYS(pages[i]), flags);
        }
        sc->match->driver->read_gtt_pte(dev, first_entry + num_entries - 1);
}

struct intel_gtt
agp_intel_gtt_get(device_t dev)
{
        struct agp_i810_softc *sc;
        struct intel_gtt res;

        sc = device_get_softc(dev);
        res.stolen_size = sc->stolen_size;
        res.gtt_total_entries = sc->gtt_total_entries;
        res.gtt_mappable_entries = sc->gtt_mappable_entries;
        res.do_idle_maps = 0;
        res.scratch_page_dma = VM_PAGE_TO_PHYS(bogus_page);
        if (sc->agp.as_aperture != NULL)
                res.gma_bus_addr = rman_get_start(sc->agp.as_aperture);
        else
                res.gma_bus_addr = 0;
        return (res);
}

static int
agp_i810_chipset_flush_setup(device_t dev)
{

        return (0);
}

static void
agp_i810_chipset_flush_teardown(device_t dev)
{

        /* Nothing to do. */
}

static void
agp_i810_chipset_flush(device_t dev)
{

        /* Nothing to do. */
}

static void
agp_i830_chipset_flush(device_t dev)
{
        struct agp_i810_softc *sc;
        uint32_t hic;
        int i;

        sc = device_get_softc(dev);
        pmap_invalidate_cache();
        hic = bus_read_4(sc->sc_res[0], AGP_I830_HIC);
        bus_write_4(sc->sc_res[0], AGP_I830_HIC, hic | (1U << 31));
        for (i = 0; i < 20000 /* 1 sec */; i++) {
                hic = bus_read_4(sc->sc_res[0], AGP_I830_HIC);
                if ((hic & (1U << 31)) == 0)
                        break;
                DELAY(50);
        }
}

static int
agp_i915_chipset_flush_alloc_page(device_t dev, uint64_t start, uint64_t end)
{
        struct agp_i810_softc *sc;
        device_t vga;

        sc = device_get_softc(dev);
        vga = device_get_parent(dev);
        sc->sc_flush_page_rid = 100;
        sc->sc_flush_page_res = BUS_ALLOC_RESOURCE(device_get_parent(vga), dev,
            SYS_RES_MEMORY, sc->sc_flush_page_rid, start, end, PAGE_SIZE,
            RF_ACTIVE);
        if (sc->sc_flush_page_res == NULL) {
                device_printf(dev, "Failed to allocate flush page at 0x%jx\n",
                    (uintmax_t)start);
                return (EINVAL);
        }
        sc->sc_flush_page_vaddr = rman_get_virtual(sc->sc_flush_page_res);
        if (bootverbose) {
                device_printf(dev, "Allocated flush page phys 0x%jx virt %p\n",
                    (uintmax_t)rman_get_start(sc->sc_flush_page_res),
                    sc->sc_flush_page_vaddr);
        }
        return (0);
}

static void
agp_i915_chipset_flush_free_page(device_t dev)
{
        struct agp_i810_softc *sc;
        device_t vga;

        sc = device_get_softc(dev);
        vga = device_get_parent(dev);
        if (sc->sc_flush_page_res == NULL)
                return;
        BUS_DEACTIVATE_RESOURCE(device_get_parent(vga), dev,
            sc->sc_flush_page_res);
        BUS_RELEASE_RESOURCE(device_get_parent(vga), dev,
            sc->sc_flush_page_res);
}

static int
agp_i915_chipset_flush_setup(device_t dev)
{
        struct agp_i810_softc *sc;
        uint32_t temp;
        int error;

        sc = device_get_softc(dev);
        temp = pci_read_config(sc->bdev, AGP_I915_IFPADDR, 4);
        if ((temp & 1) != 0) {
                temp &= ~1;
                if (bootverbose)
                        device_printf(dev,
                            "Found already configured flush page at 0x%jx\n",
                            (uintmax_t)temp);
                sc->sc_bios_allocated_flush_page = 1;
                /*
                 * In the case BIOS initialized the flush pointer (?)
                 * register, expect that BIOS also set up the resource
                 * for the page.
                 */
                error = agp_i915_chipset_flush_alloc_page(dev, temp,
                    temp + PAGE_SIZE - 1);
                if (error != 0)
                        return (error);
        } else {
                sc->sc_bios_allocated_flush_page = 0;
                error = agp_i915_chipset_flush_alloc_page(dev, 0, 0xffffffff);
                if (error != 0)
                        return (error);
                temp = rman_get_start(sc->sc_flush_page_res);
                pci_write_config(sc->bdev, AGP_I915_IFPADDR, temp | 1, 4);
        }
        return (0);
}

static void
agp_i915_chipset_flush_teardown(device_t dev)
{
        struct agp_i810_softc *sc;
        uint32_t temp;

        sc = device_get_softc(dev);
        if (sc->sc_flush_page_res == NULL)
                return;
        if (!sc->sc_bios_allocated_flush_page) {
                temp = pci_read_config(sc->bdev, AGP_I915_IFPADDR, 4);
                temp &= ~1;
                pci_write_config(sc->bdev, AGP_I915_IFPADDR, temp, 4);
        }               
        agp_i915_chipset_flush_free_page(dev);
}

static int
agp_i965_chipset_flush_setup(device_t dev)
{
        struct agp_i810_softc *sc;
        uint64_t temp;
        uint32_t temp_hi, temp_lo;
        int error;

        sc = device_get_softc(dev);

        temp_hi = pci_read_config(sc->bdev, AGP_I965_IFPADDR + 4, 4);
        temp_lo = pci_read_config(sc->bdev, AGP_I965_IFPADDR, 4);

        if ((temp_lo & 1) != 0) {
                temp = ((uint64_t)temp_hi << 32) | (temp_lo & ~1);
                if (bootverbose)
                        device_printf(dev,
                            "Found already configured flush page at 0x%jx\n",
                            (uintmax_t)temp);
                sc->sc_bios_allocated_flush_page = 1;
                /*
                 * In the case BIOS initialized the flush pointer (?)
                 * register, expect that BIOS also set up the resource
                 * for the page.
                 */
                error = agp_i915_chipset_flush_alloc_page(dev, temp,
                    temp + PAGE_SIZE - 1);
                if (error != 0)
                        return (error);
        } else {
                sc->sc_bios_allocated_flush_page = 0;
                error = agp_i915_chipset_flush_alloc_page(dev, 0, ~0);
                if (error != 0)
                        return (error);
                temp = rman_get_start(sc->sc_flush_page_res);
                pci_write_config(sc->bdev, AGP_I965_IFPADDR + 4,
                    (temp >> 32) & UINT32_MAX, 4);
                pci_write_config(sc->bdev, AGP_I965_IFPADDR,
                    (temp & UINT32_MAX) | 1, 4);
        }
        return (0);
}

static void
agp_i965_chipset_flush_teardown(device_t dev)
{
        struct agp_i810_softc *sc;
        uint32_t temp_lo;

        sc = device_get_softc(dev);
        if (sc->sc_flush_page_res == NULL)
                return;
        if (!sc->sc_bios_allocated_flush_page) {
                temp_lo = pci_read_config(sc->bdev, AGP_I965_IFPADDR, 4);
                temp_lo &= ~1;
                pci_write_config(sc->bdev, AGP_I965_IFPADDR, temp_lo, 4);
        }
        agp_i915_chipset_flush_free_page(dev);
}

static void
agp_i915_chipset_flush(device_t dev)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(dev);
        *(uint32_t *)sc->sc_flush_page_vaddr = 1;
}

int
agp_intel_gtt_chipset_flush(device_t dev)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(dev);
        sc->match->driver->chipset_flush(dev);
        return (0);
}

void
agp_intel_gtt_unmap_memory(device_t dev, struct sglist *sg_list)
{
}

int
agp_intel_gtt_map_memory(device_t dev, vm_page_t *pages, u_int num_entries,
    struct sglist **sg_list)
{
#if 0
        struct agp_i810_softc *sc;
#endif
        struct sglist *sg;
        int i;
#if 0
        int error;
        bus_dma_tag_t dmat;
#endif

        if (*sg_list != NULL)
                return (0);
#if 0
        sc = device_get_softc(dev);
#endif
        sg = sglist_alloc(num_entries, M_WAITOK /* XXXKIB */);
        for (i = 0; i < num_entries; i++) {
                sg->sg_segs[i].ss_paddr = VM_PAGE_TO_PHYS(pages[i]);
                sg->sg_segs[i].ss_len = PAGE_SIZE;
        }

#if 0
        error = bus_dma_tag_create(bus_get_dma_tag(dev),
            1 /* alignment */, 0 /* boundary */,
            1ULL << sc->match->busdma_addr_mask_sz /* lowaddr */,
            BUS_SPACE_MAXADDR /* highaddr */,
            NULL /* filtfunc */, NULL /* filtfuncarg */,
            BUS_SPACE_MAXADDR /* maxsize */,
            BUS_SPACE_UNRESTRICTED /* nsegments */,
            BUS_SPACE_MAXADDR /* maxsegsz */,
            0 /* flags */, NULL /* lockfunc */, NULL /* lockfuncarg */,
            &dmat);
        if (error != 0) {
                sglist_free(sg);
                return (error);
        }
        /* XXXKIB */
#endif
        *sg_list = sg;
        return (0);
}

static void
agp_intel_gtt_install_pte(device_t dev, u_int index, vm_paddr_t addr,
    u_int flags)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(dev);
        sc->match->driver->install_gtt_pte(dev, index, addr, flags);
}

void
agp_intel_gtt_insert_sg_entries(device_t dev, struct sglist *sg_list,
    u_int first_entry, u_int flags)
{
        struct agp_i810_softc *sc;
        vm_paddr_t spaddr;
        size_t slen;
        u_int i, j;

        sc = device_get_softc(dev);
        for (i = j = 0; j < sg_list->sg_nseg; j++) {
                spaddr = sg_list->sg_segs[i].ss_paddr;
                slen = sg_list->sg_segs[i].ss_len;
                for (; slen > 0; i++) {
                        sc->match->driver->install_gtt_pte(dev, first_entry + i,
                            spaddr, flags);
                        spaddr += AGP_PAGE_SIZE;
                        slen -= AGP_PAGE_SIZE;
                }
        }
        sc->match->driver->read_gtt_pte(dev, first_entry + i - 1);
}

void
intel_gtt_clear_range(u_int first_entry, u_int num_entries)
{

        agp_intel_gtt_clear_range(intel_agp, first_entry, num_entries);
}

void
intel_gtt_insert_pages(u_int first_entry, u_int num_entries, vm_page_t *pages,
    u_int flags)
{

        agp_intel_gtt_insert_pages(intel_agp, first_entry, num_entries,
            pages, flags);
}

struct intel_gtt *
intel_gtt_get(void)
{

        intel_private.base = agp_intel_gtt_get(intel_agp);
        return (&intel_private.base);
}

int
intel_gtt_chipset_flush(void)
{

        return (agp_intel_gtt_chipset_flush(intel_agp));
}

void
intel_gtt_unmap_memory(struct sglist *sg_list)
{

        agp_intel_gtt_unmap_memory(intel_agp, sg_list);
}

int
intel_gtt_map_memory(vm_page_t *pages, u_int num_entries,
    struct sglist **sg_list)
{

        return (agp_intel_gtt_map_memory(intel_agp, pages, num_entries,
            sg_list));
}

void
intel_gtt_insert_sg_entries(struct sglist *sg_list, u_int first_entry,
    u_int flags)
{

        agp_intel_gtt_insert_sg_entries(intel_agp, sg_list, first_entry, flags);
}

void
intel_gtt_install_pte(u_int index, vm_paddr_t addr, u_int flags)
{

        agp_intel_gtt_install_pte(intel_agp, index, addr, flags);
}

device_t
intel_gtt_get_bridge_device(void)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(intel_agp);
        return (sc->bdev);
}

vm_paddr_t
intel_gtt_read_pte_paddr(u_int entry)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(intel_agp);
        return (sc->match->driver->read_gtt_pte_paddr(intel_agp, entry));
}

u_int32_t
intel_gtt_read_pte(u_int entry)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(intel_agp);
        return (sc->match->driver->read_gtt_pte(intel_agp, entry));
}

void
intel_gtt_write(u_int entry, uint32_t val)
{
        struct agp_i810_softc *sc;

        sc = device_get_softc(intel_agp);
        return (sc->match->driver->write_gtt(intel_agp, entry, val));
}