[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / char / agp / backend.c

/*
 * AGPGART driver backend routines.
 * Copyright (C) 2004 Silicon Graphics, Inc.
 * Copyright (C) 2002-2003 Dave Jones.
 * Copyright (C) 1999 Jeff Hartmann.
 * Copyright (C) 1999 Precision Insight, Inc.
 * Copyright (C) 1999 Xi Graphics, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * JEFF HARTMANN, DAVE JONES, OR ANY OTHER CONTRIBUTORS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
 * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 * TODO:
 * - Allocate more than order 0 pages to avoid too much linear map splitting.
 */
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
#include <linux/miscdevice.h>
#include <linux/pm.h>
#include <linux/agp_backend.h>
#include <linux/agpgart.h>
#include <linux/vmalloc.h>
#include <asm/io.h>
#include "agp.h"

/* Due to XFree86 brain-damage, we can't go to 1.0 until they
 * fix some real stupidity. It's only by chance we can bump
 * past 0.99 at all due to some boolean logic error. */
#define AGPGART_VERSION_MAJOR 0
#define AGPGART_VERSION_MINOR 103
static const struct agp_version agp_current_version =
{
	.major = AGPGART_VERSION_MAJOR,
	.minor = AGPGART_VERSION_MINOR,
};

struct agp_bridge_data *(*agp_find_bridge)(struct pci_dev *) =
	&agp_generic_find_bridge;

struct agp_bridge_data *agp_bridge;
LIST_HEAD(agp_bridges);
EXPORT_SYMBOL(agp_bridge);
EXPORT_SYMBOL(agp_bridges);
EXPORT_SYMBOL(agp_find_bridge);

/**
 *	agp_backend_acquire  -  attempt to acquire an agp backend.
 *
 */
struct agp_bridge_data *agp_backend_acquire(struct pci_dev *pdev)
{
	struct agp_bridge_data *bridge;

	bridge = agp_find_bridge(pdev);

	if (!bridge)
		return NULL;

	if (atomic_read(&bridge->agp_in_use))
		return NULL;
	atomic_inc(&bridge->agp_in_use);
	return bridge;
}
EXPORT_SYMBOL(agp_backend_acquire);


/**
 *	agp_backend_release  -  release the lock on the agp backend.
 *
 *	The caller must insure that the graphics aperture translation table
 *	is read for use by another entity.
 *
 *	(Ensure that all memory it bound is unbound.)
 */
void agp_backend_release(struct agp_bridge_data *bridge)
{

	if (bridge)
		atomic_dec(&bridge->agp_in_use);
}
EXPORT_SYMBOL(agp_backend_release);


static const struct { int mem, agp; } maxes_table[] = {
	{0, 0},
	{32, 4},
	{64, 28},
	{128, 96},
	{256, 204},
	{512, 440},
	{1024, 942},
	{2048, 1920},
	{4096, 3932}
};

static int agp_find_max(void)
{
	long memory, index, result;

#if PAGE_SHIFT < 20
	memory = totalram_pages >> (20 - PAGE_SHIFT);
#else
	memory = totalram_pages << (PAGE_SHIFT - 20);
#endif
	index = 1;

	while ((memory > maxes_table[index].mem) && (index < 8))
		index++;

	result = maxes_table[index - 1].agp +
	   ( (memory - maxes_table[index - 1].mem)  *
	     (maxes_table[index].agp - maxes_table[index - 1].agp)) /
	   (maxes_table[index].mem - maxes_table[index - 1].mem);

	result = result << (20 - PAGE_SHIFT);
	return result;
}


static int agp_backend_initialize(struct agp_bridge_data *bridge)
{
	int size_value, rc, got_gatt=0, got_keylist=0;

	bridge->max_memory_agp = agp_find_max();
	bridge->version = &agp_current_version;

	if (bridge->driver->needs_scratch_page) {
		struct page *page = bridge->driver->agp_alloc_page(bridge);

		if (!page) {
			dev_err(&bridge->dev->dev,
				"can't get memory for scratch page\n");
			return -ENOMEM;
		}

		bridge->scratch_page_page = page;
		bridge->scratch_page_dma = page_to_phys(page);

		bridge->scratch_page = bridge->driver->mask_memory(bridge,
						   bridge->scratch_page_dma, 0);
	}

	size_value = bridge->driver->fetch_size();
	if (size_value == 0) {
		dev_err(&bridge->dev->dev, "can't determine aperture size\n");
		rc = -EINVAL;
		goto err_out;
	}
	if (bridge->driver->create_gatt_table(bridge)) {
		dev_err(&bridge->dev->dev,
			"can't get memory for graphics translation table\n");
		rc = -ENOMEM;
		goto err_out;
	}
	got_gatt = 1;

	bridge->key_list = vzalloc(PAGE_SIZE * 4);
	if (bridge->key_list == NULL) {
		dev_err(&bridge->dev->dev,
			"can't allocate memory for key lists\n");
		rc = -ENOMEM;
		goto err_out;
	}
	got_keylist = 1;

	/* FIXME vmalloc'd memory not guaranteed contiguous */

	if (bridge->driver->configure()) {
		dev_err(&bridge->dev->dev, "error configuring host chipset\n");
		rc = -EINVAL;
		goto err_out;
	}
	INIT_LIST_HEAD(&bridge->mapped_list);
	spin_lock_init(&bridge->mapped_lock);

	return 0;

err_out:
	if (bridge->driver->needs_scratch_page) {
		struct page *page = bridge->scratch_page_page;

		bridge->driver->agp_destroy_page(page, AGP_PAGE_DESTROY_UNMAP);
		bridge->driver->agp_destroy_page(page, AGP_PAGE_DESTROY_FREE);
	}
	if (got_gatt)
		bridge->driver->free_gatt_table(bridge);
	if (got_keylist) {
		vfree(bridge->key_list);
		bridge->key_list = NULL;
	}
	return rc;
}

/* cannot be __exit b/c as it could be called from __init code */
static void agp_backend_cleanup(struct agp_bridge_data *bridge)
{
	if (bridge->driver->cleanup)
		bridge->driver->cleanup();
	if (bridge->driver->free_gatt_table)
		bridge->driver->free_gatt_table(bridge);

	vfree(bridge->key_list);
	bridge->key_list = NULL;

	if (bridge->driver->agp_destroy_page &&
	    bridge->driver->needs_scratch_page) {
		struct page *page = bridge->scratch_page_page;

		bridge->driver->agp_destroy_page(page, AGP_PAGE_DESTROY_UNMAP);
		bridge->driver->agp_destroy_page(page, AGP_PAGE_DESTROY_FREE);
	}
}

/* When we remove the global variable agp_bridge from all drivers
 * then agp_alloc_bridge and agp_generic_find_bridge need to be updated
 */

struct agp_bridge_data *agp_alloc_bridge(void)
{
	struct agp_bridge_data *bridge;

	bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
	if (!bridge)
		return NULL;

	atomic_set(&bridge->agp_in_use, 0);
	atomic_set(&bridge->current_memory_agp, 0);

	if (list_empty(&agp_bridges))
		agp_bridge = bridge;

	return bridge;
}
EXPORT_SYMBOL(agp_alloc_bridge);


void agp_put_bridge(struct agp_bridge_data *bridge)
{
        kfree(bridge);

        if (list_empty(&agp_bridges))
                agp_bridge = NULL;
}
EXPORT_SYMBOL(agp_put_bridge);


int agp_add_bridge(struct agp_bridge_data *bridge)
{
	int error;

	if (agp_off) {
		error = -ENODEV;
		goto err_put_bridge;
	}

	if (!bridge->dev) {
		printk (KERN_DEBUG PFX "Erk, registering with no pci_dev!\n");
		error = -EINVAL;
		goto err_put_bridge;
	}

	/* Grab reference on the chipset driver. */
	if (!try_module_get(bridge->driver->owner)) {
		dev_info(&bridge->dev->dev, "can't lock chipset driver\n");
		error = -EINVAL;
		goto err_put_bridge;
	}

	error = agp_backend_initialize(bridge);
	if (error) {
		dev_info(&bridge->dev->dev,
			 "agp_backend_initialize() failed\n");
		goto err_out;
	}

	if (list_empty(&agp_bridges)) {
		error = agp_frontend_initialize();
		if (error) {
			dev_info(&bridge->dev->dev,
				 "agp_frontend_initialize() failed\n");
			goto frontend_err;
		}

		dev_info(&bridge->dev->dev, "AGP aperture is %dM @ 0x%lx\n",
			 bridge->driver->fetch_size(), bridge->gart_bus_addr);

	}

	list_add(&bridge->list, &agp_bridges);
	return 0;

frontend_err:
	agp_backend_cleanup(bridge);
err_out:
	module_put(bridge->driver->owner);
err_put_bridge:
	agp_put_bridge(bridge);
	return error;
}
EXPORT_SYMBOL_GPL(agp_add_bridge);


void agp_remove_bridge(struct agp_bridge_data *bridge)
{
	agp_backend_cleanup(bridge);
	list_del(&bridge->list);
	if (list_empty(&agp_bridges))
		agp_frontend_cleanup();
	module_put(bridge->driver->owner);
}
EXPORT_SYMBOL_GPL(agp_remove_bridge);

int agp_off;
int agp_try_unsupported_boot;
EXPORT_SYMBOL(agp_off);
EXPORT_SYMBOL(agp_try_unsupported_boot);

static int __init agp_init(void)
{
	if (!agp_off)
		printk(KERN_INFO "Linux agpgart interface v%d.%d\n",
			AGPGART_VERSION_MAJOR, AGPGART_VERSION_MINOR);
	return 0;
}

static void __exit agp_exit(void)
{
}

#ifndef MODULE
static __init int agp_setup(char *s)
{
	if (!strcmp(s,"off"))
		agp_off = 1;
	if (!strcmp(s,"try_unsupported"))
		agp_try_unsupported_boot = 1;
	return 1;
}
__setup("agp=", agp_setup);
#endif

MODULE_AUTHOR("Dave Jones <davej@redhat.com>");
MODULE_DESCRIPTION("AGP GART driver");
MODULE_LICENSE("GPL and additional rights");
MODULE_ALIAS_MISCDEV(AGPGART_MINOR);

module_init(agp_init);
module_exit(agp_exit);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* AGPGART driver backend routines.
	3	* Copyright (C) 2004 Silicon Graphics, Inc.
	4	* Copyright (C) 2002-2003 Dave Jones.
	5	* Copyright (C) 1999 Jeff Hartmann.
	6	* Copyright (C) 1999 Precision Insight, Inc.
	7	* Copyright (C) 1999 Xi Graphics, Inc.
	8	*
	9	* Permission is hereby granted, free of charge, to any person obtaining a
	10	* copy of this software and associated documentation files (the "Software"),
	11	* to deal in the Software without restriction, including without limitation
	12	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	13	* and/or sell copies of the Software, and to permit persons to whom the
	14	* Software is furnished to do so, subject to the following conditions:
	15	*
	16	* The above copyright notice and this permission notice shall be included
	17	* in all copies or substantial portions of the Software.
	18	*
	19	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
	20	* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	21	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	22	* JEFF HARTMANN, DAVE JONES, OR ANY OTHER CONTRIBUTORS BE LIABLE FOR ANY CLAIM,
	23	* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
	24	* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
	25	* OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
	26	*
	27	* TODO:
	28	* - Allocate more than order 0 pages to avoid too much linear map splitting.
	29	*/
	30	#include <linux/module.h>
	31	#include <linux/pci.h>
	32	#include <linux/init.h>
5a0e3ad6	33	#include <linux/slab.h>
1da177e4 LT	34	#include <linux/pagemap.h>
	35	#include <linux/miscdevice.h>
	36	#include <linux/pm.h>
	37	#include <linux/agp_backend.h>
	38	#include <linux/agpgart.h>
	39	#include <linux/vmalloc.h>
	40	#include <asm/io.h>
	41	#include "agp.h"
	42
	43	/* Due to XFree86 brain-damage, we can't go to 1.0 until they
	44	* fix some real stupidity. It's only by chance we can bump
	45	* past 0.99 at all due to some boolean logic error. */
	46	#define AGPGART_VERSION_MAJOR 0
a13af4b4	47	#define AGPGART_VERSION_MINOR 103
e7745d4e	48	static const struct agp_version agp_current_version =
1da177e4 LT	49	{
	50	.major = AGPGART_VERSION_MAJOR,
	51	.minor = AGPGART_VERSION_MINOR,
	52	};
	53
	54	struct agp_bridge_data (agp_find_bridge)(struct pci_dev *) =
	55	&agp_generic_find_bridge;
	56
	57	struct agp_bridge_data *agp_bridge;
	58	LIST_HEAD(agp_bridges);
	59	EXPORT_SYMBOL(agp_bridge);
	60	EXPORT_SYMBOL(agp_bridges);
	61	EXPORT_SYMBOL(agp_find_bridge);
	62
	63	/**
	64	* agp_backend_acquire - attempt to acquire an agp backend.
	65	*
	66	*/
	67	struct agp_bridge_data agp_backend_acquire(struct pci_dev pdev)
	68	{
	69	struct agp_bridge_data *bridge;
	70
	71	bridge = agp_find_bridge(pdev);
	72
	73	if (!bridge)
	74	return NULL;
	75
	76	if (atomic_read(&bridge->agp_in_use))
	77	return NULL;
	78	atomic_inc(&bridge->agp_in_use);
	79	return bridge;
	80	}
	81	EXPORT_SYMBOL(agp_backend_acquire);
	82
	83
	84	/**
	85	* agp_backend_release - release the lock on the agp backend.
	86	*
	87	* The caller must insure that the graphics aperture translation table
	88	* is read for use by another entity.
	89	*
	90	* (Ensure that all memory it bound is unbound.)
	91	*/
	92	void agp_backend_release(struct agp_bridge_data *bridge)
	93	{
	94
	95	if (bridge)
	96	atomic_dec(&bridge->agp_in_use);
	97	}
	98	EXPORT_SYMBOL(agp_backend_release);
	99
	100
5e9ad06a	101	static const struct { int mem, agp; } maxes_table[] = {
1da177e4 LT	102	{0, 0},
	103	{32, 4},
	104	{64, 28},
	105	{128, 96},
	106	{256, 204},
	107	{512, 440},
	108	{1024, 942},
	109	{2048, 1920},
	110	{4096, 3932}
	111	};
	112
	113	static int agp_find_max(void)
	114	{
	115	long memory, index, result;
	116
	117	#if PAGE_SHIFT < 20
4481374c	118	memory = totalram_pages >> (20 - PAGE_SHIFT);
1da177e4	119	#else
4481374c	120	memory = totalram_pages << (PAGE_SHIFT - 20);
1da177e4 LT	121	#endif
	122	index = 1;
	123
	124	while ((memory > maxes_table[index].mem) && (index < 8))
	125	index++;
	126
	127	result = maxes_table[index - 1].agp +
	128	( (memory - maxes_table[index - 1].mem) *
	129	(maxes_table[index].agp - maxes_table[index - 1].agp)) /
	130	(maxes_table[index].mem - maxes_table[index - 1].mem);
	131
	132	result = result << (20 - PAGE_SHIFT);
	133	return result;
	134	}
	135
	136
	137	static int agp_backend_initialize(struct agp_bridge_data *bridge)
	138	{
	139	int size_value, rc, got_gatt=0, got_keylist=0;
	140
	141	bridge->max_memory_agp = agp_find_max();
	142	bridge->version = &agp_current_version;
	143
	144	if (bridge->driver->needs_scratch_page) {
07613ba2	145	struct page *page = bridge->driver->agp_alloc_page(bridge);
1da177e4	146
07613ba2	147	if (!page) {
e3cf6951 BH	148	dev_err(&bridge->dev->dev,
e3cf6951 BH	149	"can't get memory for scratch page\n");
1da177e4 LT	150	return -ENOMEM;
	151	}
	152
c2980d8c	153	bridge->scratch_page_page = page;
a87aa5cc	154	bridge->scratch_page_dma = page_to_phys(page);
56ec4c1e DW	155
	156	bridge->scratch_page = bridge->driver->mask_memory(bridge,
	157	bridge->scratch_page_dma, 0);
1da177e4 LT	158	}
	159
	160	size_value = bridge->driver->fetch_size();
	161	if (size_value == 0) {
e3cf6951	162	dev_err(&bridge->dev->dev, "can't determine aperture size\n");
1da177e4 LT	163	rc = -EINVAL;
	164	goto err_out;
	165	}
	166	if (bridge->driver->create_gatt_table(bridge)) {
e3cf6951 BH	167	dev_err(&bridge->dev->dev,
e3cf6951 BH	168	"can't get memory for graphics translation table\n");
1da177e4 LT	169	rc = -ENOMEM;
	170	goto err_out;
	171	}
	172	got_gatt = 1;
	173
8e03bd65	174	bridge->key_list = vzalloc(PAGE_SIZE * 4);
1da177e4	175	if (bridge->key_list == NULL) {
e3cf6951 BH	176	dev_err(&bridge->dev->dev,
e3cf6951 BH	177	"can't allocate memory for key lists\n");
1da177e4 LT	178	rc = -ENOMEM;
	179	goto err_out;
	180	}
	181	got_keylist = 1;
	182
	183	/* FIXME vmalloc'd memory not guaranteed contiguous */
1da177e4 LT	184
1da177e4 LT	185	if (bridge->driver->configure()) {
e3cf6951	186	dev_err(&bridge->dev->dev, "error configuring host chipset\n");
1da177e4 LT	187	rc = -EINVAL;
	188	goto err_out;
	189	}
a8c84df9 KP	190	INIT_LIST_HEAD(&bridge->mapped_list);
a8c84df9 KP	191	spin_lock_init(&bridge->mapped_lock);
1da177e4 LT	192
	193	return 0;
	194
	195	err_out:
88d51967	196	if (bridge->driver->needs_scratch_page) {
590dfe2f	197	struct page *page = bridge->scratch_page_page;
da503fa6	198
590dfe2f MK	199	bridge->driver->agp_destroy_page(page, AGP_PAGE_DESTROY_UNMAP);
590dfe2f MK	200	bridge->driver->agp_destroy_page(page, AGP_PAGE_DESTROY_FREE);
88d51967	201	}
1da177e4 LT	202	if (got_gatt)
	203	bridge->driver->free_gatt_table(bridge);
	204	if (got_keylist) {
	205	vfree(bridge->key_list);
	206	bridge->key_list = NULL;
	207	}
	208	return rc;
	209	}
	210
	211	/* cannot be __exit b/c as it could be called from __init code */
	212	static void agp_backend_cleanup(struct agp_bridge_data *bridge)
	213	{
	214	if (bridge->driver->cleanup)
	215	bridge->driver->cleanup();
	216	if (bridge->driver->free_gatt_table)
	217	bridge->driver->free_gatt_table(bridge);
f9101210 JJ	218
	219	vfree(bridge->key_list);
	220	bridge->key_list = NULL;
1da177e4 LT	221
1da177e4 LT	222	if (bridge->driver->agp_destroy_page &&
88d51967	223	bridge->driver->needs_scratch_page) {
590dfe2f	224	struct page *page = bridge->scratch_page_page;
da503fa6	225
590dfe2f MK	226	bridge->driver->agp_destroy_page(page, AGP_PAGE_DESTROY_UNMAP);
590dfe2f MK	227	bridge->driver->agp_destroy_page(page, AGP_PAGE_DESTROY_FREE);
88d51967	228	}
1da177e4 LT	229	}
	230
	231	/* When we remove the global variable agp_bridge from all drivers
	232	* then agp_alloc_bridge and agp_generic_find_bridge need to be updated
	233	*/
	234
	235	struct agp_bridge_data *agp_alloc_bridge(void)
	236	{
0ea27d9f	237	struct agp_bridge_data *bridge;
6a92a4e0	238
0ea27d9f	239	bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
1da177e4 LT	240	if (!bridge)
	241	return NULL;
	242
1da177e4 LT	243	atomic_set(&bridge->agp_in_use, 0);
	244	atomic_set(&bridge->current_memory_agp, 0);
	245
	246	if (list_empty(&agp_bridges))
	247	agp_bridge = bridge;
	248
	249	return bridge;
	250	}
	251	EXPORT_SYMBOL(agp_alloc_bridge);
	252
	253
	254	void agp_put_bridge(struct agp_bridge_data *bridge)
	255	{
	256	kfree(bridge);
	257
	258	if (list_empty(&agp_bridges))
	259	agp_bridge = NULL;
	260	}
	261	EXPORT_SYMBOL(agp_put_bridge);
	262
	263
	264	int agp_add_bridge(struct agp_bridge_data *bridge)
	265	{
	266	int error;
	267
3f50b022 KW	268	if (agp_off) {
	269	error = -ENODEV;
	270	goto err_put_bridge;
	271	}
1da177e4 LT	272
	273	if (!bridge->dev) {
	274	printk (KERN_DEBUG PFX "Erk, registering with no pci_dev!\n");
3f50b022 KW	275	error = -EINVAL;
3f50b022 KW	276	goto err_put_bridge;
1da177e4 LT	277	}
	278
	279	/* Grab reference on the chipset driver. */
	280	if (!try_module_get(bridge->driver->owner)) {
e3cf6951	281	dev_info(&bridge->dev->dev, "can't lock chipset driver\n");
3f50b022 KW	282	error = -EINVAL;
3f50b022 KW	283	goto err_put_bridge;
1da177e4 LT	284	}
	285
	286	error = agp_backend_initialize(bridge);
	287	if (error) {
e3cf6951 BH	288	dev_info(&bridge->dev->dev,
e3cf6951 BH	289	"agp_backend_initialize() failed\n");
1da177e4 LT	290	goto err_out;
	291	}
	292
	293	if (list_empty(&agp_bridges)) {
	294	error = agp_frontend_initialize();
	295	if (error) {
e3cf6951 BH	296	dev_info(&bridge->dev->dev,
e3cf6951 BH	297	"agp_frontend_initialize() failed\n");
1da177e4 LT	298	goto frontend_err;
	299	}
	300
e3cf6951 BH	301	dev_info(&bridge->dev->dev, "AGP aperture is %dM @ 0x%lx\n",
e3cf6951 BH	302	bridge->driver->fetch_size(), bridge->gart_bus_addr);
1da177e4 LT	303
	304	}
	305
	306	list_add(&bridge->list, &agp_bridges);
	307	return 0;
	308
	309	frontend_err:
	310	agp_backend_cleanup(bridge);
	311	err_out:
	312	module_put(bridge->driver->owner);
3f50b022	313	err_put_bridge:
1da177e4 LT	314	agp_put_bridge(bridge);
	315	return error;
	316	}
	317	EXPORT_SYMBOL_GPL(agp_add_bridge);
	318
	319
	320	void agp_remove_bridge(struct agp_bridge_data *bridge)
	321	{
	322	agp_backend_cleanup(bridge);
	323	list_del(&bridge->list);
	324	if (list_empty(&agp_bridges))
	325	agp_frontend_cleanup();
	326	module_put(bridge->driver->owner);
	327	}
	328	EXPORT_SYMBOL_GPL(agp_remove_bridge);
	329
	330	int agp_off;
	331	int agp_try_unsupported_boot;
	332	EXPORT_SYMBOL(agp_off);
	333	EXPORT_SYMBOL(agp_try_unsupported_boot);
	334
	335	static int __init agp_init(void)
	336	{
	337	if (!agp_off)
70e8992e	338	printk(KERN_INFO "Linux agpgart interface v%d.%d\n",
1da177e4 LT	339	AGPGART_VERSION_MAJOR, AGPGART_VERSION_MINOR);
	340	return 0;
	341	}
	342
408b664a	343	static void __exit agp_exit(void)
1da177e4 LT	344	{
	345	}
	346
	347	#ifndef MODULE
	348	static __init int agp_setup(char *s)
	349	{
	350	if (!strcmp(s,"off"))
	351	agp_off = 1;
	352	if (!strcmp(s,"try_unsupported"))
	353	agp_try_unsupported_boot = 1;
	354	return 1;
	355	}
	356	__setup("agp=", agp_setup);
	357	#endif
	358
f4432c5c	359	MODULE_AUTHOR("Dave Jones <davej@redhat.com>");
1da177e4 LT	360	MODULE_DESCRIPTION("AGP GART driver");
	361	MODULE_LICENSE("GPL and additional rights");
	362	MODULE_ALIAS_MISCDEV(AGPGART_MINOR);
	363
	364	module_init(agp_init);
	365	module_exit(agp_exit);
	366