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/drivers/char/agp/backend.c

https://bitbucket.org/evzijst/gittest
C | 348 lines | 238 code | 60 blank | 50 comment | 33 complexity | 02f9fd2b84e13642eeb517be79303510 MD5 | raw file
  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>
 33#include <linux/pagemap.h>
 34#include <linux/miscdevice.h>
 35#include <linux/pm.h>
 36#include <linux/agp_backend.h>
 37#include <linux/agpgart.h>
 38#include <linux/vmalloc.h>
 39#include <asm/io.h>
 40#include "agp.h"
 41
 42/* Due to XFree86 brain-damage, we can't go to 1.0 until they
 43 * fix some real stupidity. It's only by chance we can bump
 44 * past 0.99 at all due to some boolean logic error. */
 45#define AGPGART_VERSION_MAJOR 0
 46#define AGPGART_VERSION_MINOR 101
 47static struct agp_version agp_current_version =
 48{
 49	.major = AGPGART_VERSION_MAJOR,
 50	.minor = AGPGART_VERSION_MINOR,
 51};
 52
 53struct agp_bridge_data *(*agp_find_bridge)(struct pci_dev *) =
 54	&agp_generic_find_bridge;
 55
 56struct agp_bridge_data *agp_bridge;
 57LIST_HEAD(agp_bridges);
 58EXPORT_SYMBOL(agp_bridge);
 59EXPORT_SYMBOL(agp_bridges);
 60EXPORT_SYMBOL(agp_find_bridge);
 61
 62/**
 63 *	agp_backend_acquire  -  attempt to acquire an agp backend.
 64 *
 65 */
 66struct agp_bridge_data *agp_backend_acquire(struct pci_dev *pdev)
 67{
 68	struct agp_bridge_data *bridge;
 69
 70	bridge = agp_find_bridge(pdev);
 71
 72	if (!bridge)
 73		return NULL;
 74
 75	if (atomic_read(&bridge->agp_in_use))
 76		return NULL;
 77	atomic_inc(&bridge->agp_in_use);
 78	return bridge;
 79}
 80EXPORT_SYMBOL(agp_backend_acquire);
 81
 82
 83/**
 84 *	agp_backend_release  -  release the lock on the agp backend.
 85 *
 86 *	The caller must insure that the graphics aperture translation table
 87 *	is read for use by another entity.
 88 *
 89 *	(Ensure that all memory it bound is unbound.)
 90 */
 91void agp_backend_release(struct agp_bridge_data *bridge)
 92{
 93
 94	if (bridge)
 95		atomic_dec(&bridge->agp_in_use);
 96}
 97EXPORT_SYMBOL(agp_backend_release);
 98
 99
100struct { int mem, agp; } maxes_table[] = {
101	{0, 0},
102	{32, 4},
103	{64, 28},
104	{128, 96},
105	{256, 204},
106	{512, 440},
107	{1024, 942},
108	{2048, 1920},
109	{4096, 3932}
110};
111
112static int agp_find_max(void)
113{
114	long memory, index, result;
115
116#if PAGE_SHIFT < 20
117	memory = num_physpages >> (20 - PAGE_SHIFT);
118#else
119	memory = num_physpages << (PAGE_SHIFT - 20);
120#endif
121	index = 1;
122
123	while ((memory > maxes_table[index].mem) && (index < 8))
124		index++;
125
126	result = maxes_table[index - 1].agp +
127	   ( (memory - maxes_table[index - 1].mem)  *
128	     (maxes_table[index].agp - maxes_table[index - 1].agp)) /
129	   (maxes_table[index].mem - maxes_table[index - 1].mem);
130
131	result = result << (20 - PAGE_SHIFT);
132	return result;
133}
134
135
136static int agp_backend_initialize(struct agp_bridge_data *bridge)
137{
138	int size_value, rc, got_gatt=0, got_keylist=0;
139
140	bridge->max_memory_agp = agp_find_max();
141	bridge->version = &agp_current_version;
142
143	if (bridge->driver->needs_scratch_page) {
144		void *addr = bridge->driver->agp_alloc_page(bridge);
145
146		if (!addr) {
147			printk(KERN_ERR PFX "unable to get memory for scratch page.\n");
148			return -ENOMEM;
149		}
150
151		bridge->scratch_page_real = virt_to_phys(addr);
152		bridge->scratch_page =
153		    bridge->driver->mask_memory(bridge, bridge->scratch_page_real, 0);
154	}
155
156	size_value = bridge->driver->fetch_size();
157	if (size_value == 0) {
158		printk(KERN_ERR PFX "unable to determine aperture size.\n");
159		rc = -EINVAL;
160		goto err_out;
161	}
162	if (bridge->driver->create_gatt_table(bridge)) {
163		printk(KERN_ERR PFX
164		    "unable to get memory for graphics translation table.\n");
165		rc = -ENOMEM;
166		goto err_out;
167	}
168	got_gatt = 1;
169
170	bridge->key_list = vmalloc(PAGE_SIZE * 4);
171	if (bridge->key_list == NULL) {
172		printk(KERN_ERR PFX "error allocating memory for key lists.\n");
173		rc = -ENOMEM;
174		goto err_out;
175	}
176	got_keylist = 1;
177
178	/* FIXME vmalloc'd memory not guaranteed contiguous */
179	memset(bridge->key_list, 0, PAGE_SIZE * 4);
180
181	if (bridge->driver->configure()) {
182		printk(KERN_ERR PFX "error configuring host chipset.\n");
183		rc = -EINVAL;
184		goto err_out;
185	}
186
187	return 0;
188
189err_out:
190	if (bridge->driver->needs_scratch_page)
191		bridge->driver->agp_destroy_page(
192				phys_to_virt(bridge->scratch_page_real));
193	if (got_gatt)
194		bridge->driver->free_gatt_table(bridge);
195	if (got_keylist) {
196		vfree(bridge->key_list);
197		bridge->key_list = NULL;
198	}
199	return rc;
200}
201
202/* cannot be __exit b/c as it could be called from __init code */
203static void agp_backend_cleanup(struct agp_bridge_data *bridge)
204{
205	if (bridge->driver->cleanup)
206		bridge->driver->cleanup();
207	if (bridge->driver->free_gatt_table)
208		bridge->driver->free_gatt_table(bridge);
209	if (bridge->key_list) {
210		vfree(bridge->key_list);
211		bridge->key_list = NULL;
212	}
213
214	if (bridge->driver->agp_destroy_page &&
215	    bridge->driver->needs_scratch_page)
216		bridge->driver->agp_destroy_page(
217				phys_to_virt(bridge->scratch_page_real));
218}
219
220/* When we remove the global variable agp_bridge from all drivers
221 * then agp_alloc_bridge and agp_generic_find_bridge need to be updated
222 */
223
224struct agp_bridge_data *agp_alloc_bridge(void)
225{
226	struct agp_bridge_data *bridge = kmalloc(sizeof(*bridge), GFP_KERNEL);
227
228	if (!bridge)
229		return NULL;
230
231	memset(bridge, 0, sizeof(*bridge));
232	atomic_set(&bridge->agp_in_use, 0);
233	atomic_set(&bridge->current_memory_agp, 0);
234
235	if (list_empty(&agp_bridges))
236		agp_bridge = bridge;
237
238	return bridge;
239}
240EXPORT_SYMBOL(agp_alloc_bridge);
241
242
243void agp_put_bridge(struct agp_bridge_data *bridge)
244{
245        kfree(bridge);
246
247        if (list_empty(&agp_bridges))
248                agp_bridge = NULL;
249}
250EXPORT_SYMBOL(agp_put_bridge);
251
252
253int agp_add_bridge(struct agp_bridge_data *bridge)
254{
255	int error;
256
257	if (agp_off)
258		return -ENODEV;
259
260	if (!bridge->dev) {
261		printk (KERN_DEBUG PFX "Erk, registering with no pci_dev!\n");
262		return -EINVAL;
263	}
264
265	/* Grab reference on the chipset driver. */
266	if (!try_module_get(bridge->driver->owner)) {
267		printk (KERN_INFO PFX "Couldn't lock chipset driver.\n");
268		return -EINVAL;
269	}
270
271	error = agp_backend_initialize(bridge);
272	if (error) {
273		printk (KERN_INFO PFX "agp_backend_initialize() failed.\n");
274		goto err_out;
275	}
276
277	if (list_empty(&agp_bridges)) {
278		error = agp_frontend_initialize();
279		if (error) {
280			printk (KERN_INFO PFX "agp_frontend_initialize() failed.\n");
281			goto frontend_err;
282		}
283
284		printk(KERN_INFO PFX "AGP aperture is %dM @ 0x%lx\n",
285			bridge->driver->fetch_size(), bridge->gart_bus_addr);
286
287	}
288
289	list_add(&bridge->list, &agp_bridges);
290	return 0;
291
292frontend_err:
293	agp_backend_cleanup(bridge);
294err_out:
295	module_put(bridge->driver->owner);
296	agp_put_bridge(bridge);
297	return error;
298}
299EXPORT_SYMBOL_GPL(agp_add_bridge);
300
301
302void agp_remove_bridge(struct agp_bridge_data *bridge)
303{
304	agp_backend_cleanup(bridge);
305	list_del(&bridge->list);
306	if (list_empty(&agp_bridges))
307		agp_frontend_cleanup();
308	module_put(bridge->driver->owner);
309}
310EXPORT_SYMBOL_GPL(agp_remove_bridge);
311
312int agp_off;
313int agp_try_unsupported_boot;
314EXPORT_SYMBOL(agp_off);
315EXPORT_SYMBOL(agp_try_unsupported_boot);
316
317static int __init agp_init(void)
318{
319	if (!agp_off)
320		printk(KERN_INFO "Linux agpgart interface v%d.%d (c) Dave Jones\n",
321			AGPGART_VERSION_MAJOR, AGPGART_VERSION_MINOR);
322	return 0;
323}
324
325void __exit agp_exit(void)
326{
327}
328
329#ifndef MODULE
330static __init int agp_setup(char *s)
331{
332	if (!strcmp(s,"off"))
333		agp_off = 1;
334	if (!strcmp(s,"try_unsupported"))
335		agp_try_unsupported_boot = 1;
336	return 1;
337}
338__setup("agp=", agp_setup);
339#endif
340
341MODULE_AUTHOR("Dave Jones <davej@codemonkey.org.uk>");
342MODULE_DESCRIPTION("AGP GART driver");
343MODULE_LICENSE("GPL and additional rights");
344MODULE_ALIAS_MISCDEV(AGPGART_MINOR);
345
346module_init(agp_init);
347module_exit(agp_exit);
348