[net-next-2.6.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;
		if (bridge->driver->agp_map_page) {
			if (bridge->driver->agp_map_page(page,
							 &bridge->scratch_page_dma)) {
				dev_err(&bridge->dev->dev,
					"unable to dma-map scratch page\n");
				rc = -ENOMEM;
				goto err_out_nounmap;
			}
		} else {
			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 = vmalloc(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 */
	memset(bridge->key_list, 0, PAGE_SIZE * 4);

	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 &&
	    bridge->driver->agp_unmap_page) {
		bridge->driver->agp_unmap_page(bridge->scratch_page_page,
					       bridge->scratch_page_dma);
	}
err_out_nounmap:
	if (bridge->driver->needs_scratch_page) {
		void *va = page_address(bridge->scratch_page_page);

		bridge->driver->agp_destroy_page(va, AGP_PAGE_DESTROY_UNMAP);
		bridge->driver->agp_destroy_page(va, 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) {
		void *va = page_address(bridge->scratch_page_page);

		if (bridge->driver->agp_unmap_page)
			bridge->driver->agp_unmap_page(bridge->scratch_page_page,
						       bridge->scratch_page_dma);

		bridge->driver->agp_destroy_page(va, AGP_PAGE_DESTROY_UNMAP);
		bridge->driver->agp_destroy_page(va, 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;
56ec4c1e	154	if (bridge->driver->agp_map_page) {
c2980d8c	155	if (bridge->driver->agp_map_page(page,
56ec4c1e DW	156	&bridge->scratch_page_dma)) {
	157	dev_err(&bridge->dev->dev,
	158	"unable to dma-map scratch page\n");
	159	rc = -ENOMEM;
	160	goto err_out_nounmap;
	161	}
	162	} else {
6a12235c	163	bridge->scratch_page_dma = page_to_phys(page);
ff663cf8	164	}
56ec4c1e DW	165
	166	bridge->scratch_page = bridge->driver->mask_memory(bridge,
	167	bridge->scratch_page_dma, 0);
1da177e4 LT	168	}
	169
	170	size_value = bridge->driver->fetch_size();
	171	if (size_value == 0) {
e3cf6951	172	dev_err(&bridge->dev->dev, "can't determine aperture size\n");
1da177e4 LT	173	rc = -EINVAL;
	174	goto err_out;
	175	}
	176	if (bridge->driver->create_gatt_table(bridge)) {
e3cf6951 BH	177	dev_err(&bridge->dev->dev,
e3cf6951 BH	178	"can't get memory for graphics translation table\n");
1da177e4 LT	179	rc = -ENOMEM;
	180	goto err_out;
	181	}
	182	got_gatt = 1;
	183
	184	bridge->key_list = vmalloc(PAGE_SIZE * 4);
	185	if (bridge->key_list == NULL) {
e3cf6951 BH	186	dev_err(&bridge->dev->dev,
e3cf6951 BH	187	"can't allocate memory for key lists\n");
1da177e4 LT	188	rc = -ENOMEM;
	189	goto err_out;
	190	}
	191	got_keylist = 1;
	192
	193	/* FIXME vmalloc'd memory not guaranteed contiguous */
	194	memset(bridge->key_list, 0, PAGE_SIZE * 4);
	195
	196	if (bridge->driver->configure()) {
e3cf6951	197	dev_err(&bridge->dev->dev, "error configuring host chipset\n");
1da177e4 LT	198	rc = -EINVAL;
	199	goto err_out;
	200	}
a8c84df9 KP	201	INIT_LIST_HEAD(&bridge->mapped_list);
a8c84df9 KP	202	spin_lock_init(&bridge->mapped_lock);
1da177e4 LT	203
	204	return 0;
	205
	206	err_out:
ff663cf8 ZW	207	if (bridge->driver->needs_scratch_page &&
ff663cf8 ZW	208	bridge->driver->agp_unmap_page) {
c2980d8c DW	209	bridge->driver->agp_unmap_page(bridge->scratch_page_page,
c2980d8c DW	210	bridge->scratch_page_dma);
ff663cf8 ZW	211	}
ff663cf8 ZW	212	err_out_nounmap:
88d51967	213	if (bridge->driver->needs_scratch_page) {
c2980d8c	214	void *va = page_address(bridge->scratch_page_page);
da503fa6 JB	215
	216	bridge->driver->agp_destroy_page(va, AGP_PAGE_DESTROY_UNMAP);
	217	bridge->driver->agp_destroy_page(va, AGP_PAGE_DESTROY_FREE);
88d51967	218	}
1da177e4 LT	219	if (got_gatt)
	220	bridge->driver->free_gatt_table(bridge);
	221	if (got_keylist) {
	222	vfree(bridge->key_list);
	223	bridge->key_list = NULL;
	224	}
	225	return rc;
	226	}
	227
	228	/* cannot be __exit b/c as it could be called from __init code */
	229	static void agp_backend_cleanup(struct agp_bridge_data *bridge)
	230	{
	231	if (bridge->driver->cleanup)
	232	bridge->driver->cleanup();
	233	if (bridge->driver->free_gatt_table)
	234	bridge->driver->free_gatt_table(bridge);
f9101210 JJ	235
	236	vfree(bridge->key_list);
	237	bridge->key_list = NULL;
1da177e4 LT	238
1da177e4 LT	239	if (bridge->driver->agp_destroy_page &&
88d51967	240	bridge->driver->needs_scratch_page) {
c2980d8c	241	void *va = page_address(bridge->scratch_page_page);
da503fa6	242
ff663cf8	243	if (bridge->driver->agp_unmap_page)
c2980d8c DW	244	bridge->driver->agp_unmap_page(bridge->scratch_page_page,
c2980d8c DW	245	bridge->scratch_page_dma);
ff663cf8	246
da503fa6 JB	247	bridge->driver->agp_destroy_page(va, AGP_PAGE_DESTROY_UNMAP);
da503fa6 JB	248	bridge->driver->agp_destroy_page(va, AGP_PAGE_DESTROY_FREE);
88d51967	249	}
1da177e4 LT	250	}
	251
	252	/* When we remove the global variable agp_bridge from all drivers
	253	* then agp_alloc_bridge and agp_generic_find_bridge need to be updated
	254	*/
	255
	256	struct agp_bridge_data *agp_alloc_bridge(void)
	257	{
0ea27d9f	258	struct agp_bridge_data *bridge;
6a92a4e0	259
0ea27d9f	260	bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
1da177e4 LT	261	if (!bridge)
	262	return NULL;
	263
1da177e4 LT	264	atomic_set(&bridge->agp_in_use, 0);
	265	atomic_set(&bridge->current_memory_agp, 0);
	266
	267	if (list_empty(&agp_bridges))
	268	agp_bridge = bridge;
	269
	270	return bridge;
	271	}
	272	EXPORT_SYMBOL(agp_alloc_bridge);
	273
	274
	275	void agp_put_bridge(struct agp_bridge_data *bridge)
	276	{
	277	kfree(bridge);
	278
	279	if (list_empty(&agp_bridges))
	280	agp_bridge = NULL;
	281	}
	282	EXPORT_SYMBOL(agp_put_bridge);
	283
	284
	285	int agp_add_bridge(struct agp_bridge_data *bridge)
	286	{
	287	int error;
	288
3f50b022 KW	289	if (agp_off) {
	290	error = -ENODEV;
	291	goto err_put_bridge;
	292	}
1da177e4 LT	293
	294	if (!bridge->dev) {
	295	printk (KERN_DEBUG PFX "Erk, registering with no pci_dev!\n");
3f50b022 KW	296	error = -EINVAL;
3f50b022 KW	297	goto err_put_bridge;
1da177e4 LT	298	}
	299
	300	/* Grab reference on the chipset driver. */
	301	if (!try_module_get(bridge->driver->owner)) {
e3cf6951	302	dev_info(&bridge->dev->dev, "can't lock chipset driver\n");
3f50b022 KW	303	error = -EINVAL;
3f50b022 KW	304	goto err_put_bridge;
1da177e4 LT	305	}
	306
	307	error = agp_backend_initialize(bridge);
	308	if (error) {
e3cf6951 BH	309	dev_info(&bridge->dev->dev,
e3cf6951 BH	310	"agp_backend_initialize() failed\n");
1da177e4 LT	311	goto err_out;
	312	}
	313
	314	if (list_empty(&agp_bridges)) {
	315	error = agp_frontend_initialize();
	316	if (error) {
e3cf6951 BH	317	dev_info(&bridge->dev->dev,
e3cf6951 BH	318	"agp_frontend_initialize() failed\n");
1da177e4 LT	319	goto frontend_err;
	320	}
	321
e3cf6951 BH	322	dev_info(&bridge->dev->dev, "AGP aperture is %dM @ 0x%lx\n",
e3cf6951 BH	323	bridge->driver->fetch_size(), bridge->gart_bus_addr);
1da177e4 LT	324
	325	}
	326
	327	list_add(&bridge->list, &agp_bridges);
	328	return 0;
	329
	330	frontend_err:
	331	agp_backend_cleanup(bridge);
	332	err_out:
	333	module_put(bridge->driver->owner);
3f50b022	334	err_put_bridge:
1da177e4 LT	335	agp_put_bridge(bridge);
	336	return error;
	337	}
	338	EXPORT_SYMBOL_GPL(agp_add_bridge);
	339
	340
	341	void agp_remove_bridge(struct agp_bridge_data *bridge)
	342	{
	343	agp_backend_cleanup(bridge);
	344	list_del(&bridge->list);
	345	if (list_empty(&agp_bridges))
	346	agp_frontend_cleanup();
	347	module_put(bridge->driver->owner);
	348	}
	349	EXPORT_SYMBOL_GPL(agp_remove_bridge);
	350
	351	int agp_off;
	352	int agp_try_unsupported_boot;
	353	EXPORT_SYMBOL(agp_off);
	354	EXPORT_SYMBOL(agp_try_unsupported_boot);
	355
	356	static int __init agp_init(void)
	357	{
	358	if (!agp_off)
70e8992e	359	printk(KERN_INFO "Linux agpgart interface v%d.%d\n",
1da177e4 LT	360	AGPGART_VERSION_MAJOR, AGPGART_VERSION_MINOR);
	361	return 0;
	362	}
	363
408b664a	364	static void __exit agp_exit(void)
1da177e4 LT	365	{
	366	}
	367
	368	#ifndef MODULE
	369	static __init int agp_setup(char *s)
	370	{
	371	if (!strcmp(s,"off"))
	372	agp_off = 1;
	373	if (!strcmp(s,"try_unsupported"))
	374	agp_try_unsupported_boot = 1;
	375	return 1;
	376	}
	377	__setup("agp=", agp_setup);
	378	#endif
	379
f4432c5c	380	MODULE_AUTHOR("Dave Jones <davej@redhat.com>");
1da177e4 LT	381	MODULE_DESCRIPTION("AGP GART driver");
	382	MODULE_LICENSE("GPL and additional rights");
	383	MODULE_ALIAS_MISCDEV(AGPGART_MINOR);
	384
	385	module_init(agp_init);
	386	module_exit(agp_exit);
	387