xref: /openbmc/linux/drivers/char/agp/i460-agp.c (revision 2cf1c348)
1 /*
2  * For documentation on the i460 AGP interface, see Chapter 7 (AGP Subsystem) of
3  * the "Intel 460GTX Chipset Software Developer's Manual":
4  * http://www.intel.com/design/archives/itanium/downloads/248704.htm
5  */
6 /*
7  * 460GX support by Chris Ahna <christopher.j.ahna@intel.com>
8  * Clean up & simplification by David Mosberger-Tang <davidm@hpl.hp.com>
9  */
10 #include <linux/module.h>
11 #include <linux/pci.h>
12 #include <linux/init.h>
13 #include <linux/string.h>
14 #include <linux/slab.h>
15 #include <linux/agp_backend.h>
16 #include <linux/log2.h>
17 
18 #include "agp.h"
19 
20 #define INTEL_I460_BAPBASE		0x98
21 #define INTEL_I460_GXBCTL		0xa0
22 #define INTEL_I460_AGPSIZ		0xa2
23 #define INTEL_I460_ATTBASE		0xfe200000
24 #define INTEL_I460_GATT_VALID		(1UL << 24)
25 #define INTEL_I460_GATT_COHERENT	(1UL << 25)
26 
27 /*
28  * The i460 can operate with large (4MB) pages, but there is no sane way to support this
29  * within the current kernel/DRM environment, so we disable the relevant code for now.
30  * See also comments in ia64_alloc_page()...
31  */
32 #define I460_LARGE_IO_PAGES		0
33 
34 #if I460_LARGE_IO_PAGES
35 # define I460_IO_PAGE_SHIFT		i460.io_page_shift
36 #else
37 # define I460_IO_PAGE_SHIFT		12
38 #endif
39 
40 #define I460_IOPAGES_PER_KPAGE		(PAGE_SIZE >> I460_IO_PAGE_SHIFT)
41 #define I460_KPAGES_PER_IOPAGE		(1 << (I460_IO_PAGE_SHIFT - PAGE_SHIFT))
42 #define I460_SRAM_IO_DISABLE		(1 << 4)
43 #define I460_BAPBASE_ENABLE		(1 << 3)
44 #define I460_AGPSIZ_MASK		0x7
45 #define I460_4M_PS			(1 << 1)
46 
47 /* Control bits for Out-Of-GART coherency and Burst Write Combining */
48 #define I460_GXBCTL_OOG		(1UL << 0)
49 #define I460_GXBCTL_BWC		(1UL << 2)
50 
51 /*
52  * gatt_table entries are 32-bits wide on the i460; the generic code ought to declare the
53  * gatt_table and gatt_table_real pointers a "void *"...
54  */
55 #define RD_GATT(index)		readl((u32 *) i460.gatt + (index))
56 #define WR_GATT(index, val)	writel((val), (u32 *) i460.gatt + (index))
57 /*
58  * The 460 spec says we have to read the last location written to make sure that all
59  * writes have taken effect
60  */
61 #define WR_FLUSH_GATT(index)	RD_GATT(index)
62 
63 static unsigned long i460_mask_memory (struct agp_bridge_data *bridge,
64 				       dma_addr_t addr, int type);
65 
66 static struct {
67 	void *gatt;				/* ioremap'd GATT area */
68 
69 	/* i460 supports multiple GART page sizes, so GART pageshift is dynamic: */
70 	u8 io_page_shift;
71 
72 	/* BIOS configures chipset to one of 2 possible apbase values: */
73 	u8 dynamic_apbase;
74 
75 	/* structure for tracking partial use of 4MB GART pages: */
76 	struct lp_desc {
77 		unsigned long *alloced_map;	/* bitmap of kernel-pages in use */
78 		int refcount;			/* number of kernel pages using the large page */
79 		u64 paddr;			/* physical address of large page */
80 		struct page *page; 		/* page pointer */
81 	} *lp_desc;
82 } i460;
83 
84 static const struct aper_size_info_8 i460_sizes[3] =
85 {
86 	/*
87 	 * The 32GB aperture is only available with a 4M GART page size.  Due to the
88 	 * dynamic GART page size, we can't figure out page_order or num_entries until
89 	 * runtime.
90 	 */
91 	{32768, 0, 0, 4},
92 	{1024, 0, 0, 2},
93 	{256, 0, 0, 1}
94 };
95 
96 static struct gatt_mask i460_masks[] =
97 {
98 	{
99 	  .mask = INTEL_I460_GATT_VALID | INTEL_I460_GATT_COHERENT,
100 	  .type = 0
101 	}
102 };
103 
104 static int i460_fetch_size (void)
105 {
106 	int i;
107 	u8 temp;
108 	struct aper_size_info_8 *values;
109 
110 	/* Determine the GART page size */
111 	pci_read_config_byte(agp_bridge->dev, INTEL_I460_GXBCTL, &temp);
112 	i460.io_page_shift = (temp & I460_4M_PS) ? 22 : 12;
113 	pr_debug("i460_fetch_size: io_page_shift=%d\n", i460.io_page_shift);
114 
115 	if (i460.io_page_shift != I460_IO_PAGE_SHIFT) {
116 		printk(KERN_ERR PFX
117 			"I/O (GART) page-size %luKB doesn't match expected "
118 				"size %luKB\n",
119 			1UL << (i460.io_page_shift - 10),
120 			1UL << (I460_IO_PAGE_SHIFT));
121 		return 0;
122 	}
123 
124 	values = A_SIZE_8(agp_bridge->driver->aperture_sizes);
125 
126 	pci_read_config_byte(agp_bridge->dev, INTEL_I460_AGPSIZ, &temp);
127 
128 	/* Exit now if the IO drivers for the GART SRAMS are turned off */
129 	if (temp & I460_SRAM_IO_DISABLE) {
130 		printk(KERN_ERR PFX "GART SRAMS disabled on 460GX chipset\n");
131 		printk(KERN_ERR PFX "AGPGART operation not possible\n");
132 		return 0;
133 	}
134 
135 	/* Make sure we don't try to create an 2 ^ 23 entry GATT */
136 	if ((i460.io_page_shift == 0) && ((temp & I460_AGPSIZ_MASK) == 4)) {
137 		printk(KERN_ERR PFX "We can't have a 32GB aperture with 4KB GART pages\n");
138 		return 0;
139 	}
140 
141 	/* Determine the proper APBASE register */
142 	if (temp & I460_BAPBASE_ENABLE)
143 		i460.dynamic_apbase = INTEL_I460_BAPBASE;
144 	else
145 		i460.dynamic_apbase = AGP_APBASE;
146 
147 	for (i = 0; i < agp_bridge->driver->num_aperture_sizes; i++) {
148 		/*
149 		 * Dynamically calculate the proper num_entries and page_order values for
150 		 * the define aperture sizes. Take care not to shift off the end of
151 		 * values[i].size.
152 		 */
153 		values[i].num_entries = (values[i].size << 8) >> (I460_IO_PAGE_SHIFT - 12);
154 		values[i].page_order = ilog2((sizeof(u32)*values[i].num_entries) >> PAGE_SHIFT);
155 	}
156 
157 	for (i = 0; i < agp_bridge->driver->num_aperture_sizes; i++) {
158 		/* Neglect control bits when matching up size_value */
159 		if ((temp & I460_AGPSIZ_MASK) == values[i].size_value) {
160 			agp_bridge->previous_size = agp_bridge->current_size = (void *) (values + i);
161 			agp_bridge->aperture_size_idx = i;
162 			return values[i].size;
163 		}
164 	}
165 
166 	return 0;
167 }
168 
169 /* There isn't anything to do here since 460 has no GART TLB. */
170 static void i460_tlb_flush (struct agp_memory *mem)
171 {
172 	return;
173 }
174 
175 /*
176  * This utility function is needed to prevent corruption of the control bits
177  * which are stored along with the aperture size in 460's AGPSIZ register
178  */
179 static void i460_write_agpsiz (u8 size_value)
180 {
181 	u8 temp;
182 
183 	pci_read_config_byte(agp_bridge->dev, INTEL_I460_AGPSIZ, &temp);
184 	pci_write_config_byte(agp_bridge->dev, INTEL_I460_AGPSIZ,
185 			      ((temp & ~I460_AGPSIZ_MASK) | size_value));
186 }
187 
188 static void i460_cleanup (void)
189 {
190 	struct aper_size_info_8 *previous_size;
191 
192 	previous_size = A_SIZE_8(agp_bridge->previous_size);
193 	i460_write_agpsiz(previous_size->size_value);
194 
195 	if (I460_IO_PAGE_SHIFT > PAGE_SHIFT)
196 		kfree(i460.lp_desc);
197 }
198 
199 static int i460_configure (void)
200 {
201 	union {
202 		u32 small[2];
203 		u64 large;
204 	} temp;
205 	size_t size;
206 	u8 scratch;
207 	struct aper_size_info_8 *current_size;
208 
209 	temp.large = 0;
210 
211 	current_size = A_SIZE_8(agp_bridge->current_size);
212 	i460_write_agpsiz(current_size->size_value);
213 
214 	/*
215 	 * Do the necessary rigmarole to read all eight bytes of APBASE.
216 	 * This has to be done since the AGP aperture can be above 4GB on
217 	 * 460 based systems.
218 	 */
219 	pci_read_config_dword(agp_bridge->dev, i460.dynamic_apbase, &(temp.small[0]));
220 	pci_read_config_dword(agp_bridge->dev, i460.dynamic_apbase + 4, &(temp.small[1]));
221 
222 	/* Clear BAR control bits */
223 	agp_bridge->gart_bus_addr = temp.large & ~((1UL << 3) - 1);
224 
225 	pci_read_config_byte(agp_bridge->dev, INTEL_I460_GXBCTL, &scratch);
226 	pci_write_config_byte(agp_bridge->dev, INTEL_I460_GXBCTL,
227 			      (scratch & 0x02) | I460_GXBCTL_OOG | I460_GXBCTL_BWC);
228 
229 	/*
230 	 * Initialize partial allocation trackers if a GART page is bigger than a kernel
231 	 * page.
232 	 */
233 	if (I460_IO_PAGE_SHIFT > PAGE_SHIFT) {
234 		size = current_size->num_entries * sizeof(i460.lp_desc[0]);
235 		i460.lp_desc = kzalloc(size, GFP_KERNEL);
236 		if (!i460.lp_desc)
237 			return -ENOMEM;
238 	}
239 	return 0;
240 }
241 
242 static int i460_create_gatt_table (struct agp_bridge_data *bridge)
243 {
244 	int page_order, num_entries, i;
245 	void *temp;
246 
247 	/*
248 	 * Load up the fixed address of the GART SRAMS which hold our GATT table.
249 	 */
250 	temp = agp_bridge->current_size;
251 	page_order = A_SIZE_8(temp)->page_order;
252 	num_entries = A_SIZE_8(temp)->num_entries;
253 
254 	i460.gatt = ioremap(INTEL_I460_ATTBASE, PAGE_SIZE << page_order);
255 	if (!i460.gatt) {
256 		printk(KERN_ERR PFX "ioremap failed\n");
257 		return -ENOMEM;
258 	}
259 
260 	/* These are no good, the should be removed from the agp_bridge strucure... */
261 	agp_bridge->gatt_table_real = NULL;
262 	agp_bridge->gatt_table = NULL;
263 	agp_bridge->gatt_bus_addr = 0;
264 
265 	for (i = 0; i < num_entries; ++i)
266 		WR_GATT(i, 0);
267 	WR_FLUSH_GATT(i - 1);
268 	return 0;
269 }
270 
271 static int i460_free_gatt_table (struct agp_bridge_data *bridge)
272 {
273 	int num_entries, i;
274 	void *temp;
275 
276 	temp = agp_bridge->current_size;
277 
278 	num_entries = A_SIZE_8(temp)->num_entries;
279 
280 	for (i = 0; i < num_entries; ++i)
281 		WR_GATT(i, 0);
282 	WR_FLUSH_GATT(num_entries - 1);
283 
284 	iounmap(i460.gatt);
285 	return 0;
286 }
287 
288 /*
289  * The following functions are called when the I/O (GART) page size is smaller than
290  * PAGE_SIZE.
291  */
292 
293 static int i460_insert_memory_small_io_page (struct agp_memory *mem,
294 				off_t pg_start, int type)
295 {
296 	unsigned long paddr, io_pg_start, io_page_size;
297 	int i, j, k, num_entries;
298 	void *temp;
299 
300 	pr_debug("i460_insert_memory_small_io_page(mem=%p, pg_start=%ld, type=%d, paddr0=0x%lx)\n",
301 		 mem, pg_start, type, page_to_phys(mem->pages[0]));
302 
303 	if (type >= AGP_USER_TYPES || mem->type >= AGP_USER_TYPES)
304 		return -EINVAL;
305 
306 	io_pg_start = I460_IOPAGES_PER_KPAGE * pg_start;
307 
308 	temp = agp_bridge->current_size;
309 	num_entries = A_SIZE_8(temp)->num_entries;
310 
311 	if ((io_pg_start + I460_IOPAGES_PER_KPAGE * mem->page_count) > num_entries) {
312 		printk(KERN_ERR PFX "Looks like we're out of AGP memory\n");
313 		return -EINVAL;
314 	}
315 
316 	j = io_pg_start;
317 	while (j < (io_pg_start + I460_IOPAGES_PER_KPAGE * mem->page_count)) {
318 		if (!PGE_EMPTY(agp_bridge, RD_GATT(j))) {
319 			pr_debug("i460_insert_memory_small_io_page: GATT[%d]=0x%x is busy\n",
320 				 j, RD_GATT(j));
321 			return -EBUSY;
322 		}
323 		j++;
324 	}
325 
326 	io_page_size = 1UL << I460_IO_PAGE_SHIFT;
327 	for (i = 0, j = io_pg_start; i < mem->page_count; i++) {
328 		paddr = page_to_phys(mem->pages[i]);
329 		for (k = 0; k < I460_IOPAGES_PER_KPAGE; k++, j++, paddr += io_page_size)
330 			WR_GATT(j, i460_mask_memory(agp_bridge, paddr, mem->type));
331 	}
332 	WR_FLUSH_GATT(j - 1);
333 	return 0;
334 }
335 
336 static int i460_remove_memory_small_io_page(struct agp_memory *mem,
337 				off_t pg_start, int type)
338 {
339 	int i;
340 
341 	pr_debug("i460_remove_memory_small_io_page(mem=%p, pg_start=%ld, type=%d)\n",
342 		 mem, pg_start, type);
343 
344 	pg_start = I460_IOPAGES_PER_KPAGE * pg_start;
345 
346 	for (i = pg_start; i < (pg_start + I460_IOPAGES_PER_KPAGE * mem->page_count); i++)
347 		WR_GATT(i, 0);
348 	WR_FLUSH_GATT(i - 1);
349 	return 0;
350 }
351 
352 #if I460_LARGE_IO_PAGES
353 
354 /*
355  * These functions are called when the I/O (GART) page size exceeds PAGE_SIZE.
356  *
357  * This situation is interesting since AGP memory allocations that are smaller than a
358  * single GART page are possible.  The i460.lp_desc array tracks partial allocation of the
359  * large GART pages to work around this issue.
360  *
361  * i460.lp_desc[pg_num].refcount tracks the number of kernel pages in use within GART page
362  * pg_num.  i460.lp_desc[pg_num].paddr is the physical address of the large page and
363  * i460.lp_desc[pg_num].alloced_map is a bitmap of kernel pages that are in use (allocated).
364  */
365 
366 static int i460_alloc_large_page (struct lp_desc *lp)
367 {
368 	unsigned long order = I460_IO_PAGE_SHIFT - PAGE_SHIFT;
369 	size_t map_size;
370 
371 	lp->page = alloc_pages(GFP_KERNEL, order);
372 	if (!lp->page) {
373 		printk(KERN_ERR PFX "Couldn't alloc 4M GART page...\n");
374 		return -ENOMEM;
375 	}
376 
377 	map_size = ((I460_KPAGES_PER_IOPAGE + BITS_PER_LONG - 1) & -BITS_PER_LONG)/8;
378 	lp->alloced_map = kzalloc(map_size, GFP_KERNEL);
379 	if (!lp->alloced_map) {
380 		__free_pages(lp->page, order);
381 		printk(KERN_ERR PFX "Out of memory, we're in trouble...\n");
382 		return -ENOMEM;
383 	}
384 
385 	lp->paddr = page_to_phys(lp->page);
386 	lp->refcount = 0;
387 	atomic_add(I460_KPAGES_PER_IOPAGE, &agp_bridge->current_memory_agp);
388 	return 0;
389 }
390 
391 static void i460_free_large_page (struct lp_desc *lp)
392 {
393 	kfree(lp->alloced_map);
394 	lp->alloced_map = NULL;
395 
396 	__free_pages(lp->page, I460_IO_PAGE_SHIFT - PAGE_SHIFT);
397 	atomic_sub(I460_KPAGES_PER_IOPAGE, &agp_bridge->current_memory_agp);
398 }
399 
400 static int i460_insert_memory_large_io_page (struct agp_memory *mem,
401 				off_t pg_start, int type)
402 {
403 	int i, start_offset, end_offset, idx, pg, num_entries;
404 	struct lp_desc *start, *end, *lp;
405 	void *temp;
406 
407 	if (type >= AGP_USER_TYPES || mem->type >= AGP_USER_TYPES)
408 		return -EINVAL;
409 
410 	temp = agp_bridge->current_size;
411 	num_entries = A_SIZE_8(temp)->num_entries;
412 
413 	/* Figure out what pg_start means in terms of our large GART pages */
414 	start = &i460.lp_desc[pg_start / I460_KPAGES_PER_IOPAGE];
415 	end = &i460.lp_desc[(pg_start + mem->page_count - 1) / I460_KPAGES_PER_IOPAGE];
416 	start_offset = pg_start % I460_KPAGES_PER_IOPAGE;
417 	end_offset = (pg_start + mem->page_count - 1) % I460_KPAGES_PER_IOPAGE;
418 
419 	if (end > i460.lp_desc + num_entries) {
420 		printk(KERN_ERR PFX "Looks like we're out of AGP memory\n");
421 		return -EINVAL;
422 	}
423 
424 	/* Check if the requested region of the aperture is free */
425 	for (lp = start; lp <= end; ++lp) {
426 		if (!lp->alloced_map)
427 			continue;	/* OK, the entire large page is available... */
428 
429 		for (idx = ((lp == start) ? start_offset : 0);
430 		     idx < ((lp == end) ? (end_offset + 1) : I460_KPAGES_PER_IOPAGE);
431 		     idx++)
432 		{
433 			if (test_bit(idx, lp->alloced_map))
434 				return -EBUSY;
435 		}
436 	}
437 
438 	for (lp = start, i = 0; lp <= end; ++lp) {
439 		if (!lp->alloced_map) {
440 			/* Allocate new GART pages... */
441 			if (i460_alloc_large_page(lp) < 0)
442 				return -ENOMEM;
443 			pg = lp - i460.lp_desc;
444 			WR_GATT(pg, i460_mask_memory(agp_bridge,
445 						     lp->paddr, 0));
446 			WR_FLUSH_GATT(pg);
447 		}
448 
449 		for (idx = ((lp == start) ? start_offset : 0);
450 		     idx < ((lp == end) ? (end_offset + 1) : I460_KPAGES_PER_IOPAGE);
451 		     idx++, i++)
452 		{
453 			mem->pages[i] = lp->page;
454 			__set_bit(idx, lp->alloced_map);
455 			++lp->refcount;
456 		}
457 	}
458 	return 0;
459 }
460 
461 static int i460_remove_memory_large_io_page (struct agp_memory *mem,
462 				off_t pg_start, int type)
463 {
464 	int i, pg, start_offset, end_offset, idx, num_entries;
465 	struct lp_desc *start, *end, *lp;
466 	void *temp;
467 
468 	temp = agp_bridge->current_size;
469 	num_entries = A_SIZE_8(temp)->num_entries;
470 
471 	/* Figure out what pg_start means in terms of our large GART pages */
472 	start = &i460.lp_desc[pg_start / I460_KPAGES_PER_IOPAGE];
473 	end = &i460.lp_desc[(pg_start + mem->page_count - 1) / I460_KPAGES_PER_IOPAGE];
474 	start_offset = pg_start % I460_KPAGES_PER_IOPAGE;
475 	end_offset = (pg_start + mem->page_count - 1) % I460_KPAGES_PER_IOPAGE;
476 
477 	for (i = 0, lp = start; lp <= end; ++lp) {
478 		for (idx = ((lp == start) ? start_offset : 0);
479 		     idx < ((lp == end) ? (end_offset + 1) : I460_KPAGES_PER_IOPAGE);
480 		     idx++, i++)
481 		{
482 			mem->pages[i] = NULL;
483 			__clear_bit(idx, lp->alloced_map);
484 			--lp->refcount;
485 		}
486 
487 		/* Free GART pages if they are unused */
488 		if (lp->refcount == 0) {
489 			pg = lp - i460.lp_desc;
490 			WR_GATT(pg, 0);
491 			WR_FLUSH_GATT(pg);
492 			i460_free_large_page(lp);
493 		}
494 	}
495 	return 0;
496 }
497 
498 /* Wrapper routines to call the approriate {small_io_page,large_io_page} function */
499 
500 static int i460_insert_memory (struct agp_memory *mem,
501 				off_t pg_start, int type)
502 {
503 	if (I460_IO_PAGE_SHIFT <= PAGE_SHIFT)
504 		return i460_insert_memory_small_io_page(mem, pg_start, type);
505 	else
506 		return i460_insert_memory_large_io_page(mem, pg_start, type);
507 }
508 
509 static int i460_remove_memory (struct agp_memory *mem,
510 				off_t pg_start, int type)
511 {
512 	if (I460_IO_PAGE_SHIFT <= PAGE_SHIFT)
513 		return i460_remove_memory_small_io_page(mem, pg_start, type);
514 	else
515 		return i460_remove_memory_large_io_page(mem, pg_start, type);
516 }
517 
518 /*
519  * If the I/O (GART) page size is bigger than the kernel page size, we don't want to
520  * allocate memory until we know where it is to be bound in the aperture (a
521  * multi-kernel-page alloc might fit inside of an already allocated GART page).
522  *
523  * Let's just hope nobody counts on the allocated AGP memory being there before bind time
524  * (I don't think current drivers do)...
525  */
526 static struct page *i460_alloc_page (struct agp_bridge_data *bridge)
527 {
528 	void *page;
529 
530 	if (I460_IO_PAGE_SHIFT <= PAGE_SHIFT) {
531 		page = agp_generic_alloc_page(agp_bridge);
532 	} else
533 		/* Returning NULL would cause problems */
534 		/* AK: really dubious code. */
535 		page = (void *)~0UL;
536 	return page;
537 }
538 
539 static void i460_destroy_page (struct page *page, int flags)
540 {
541 	if (I460_IO_PAGE_SHIFT <= PAGE_SHIFT) {
542 		agp_generic_destroy_page(page, flags);
543 	}
544 }
545 
546 #endif /* I460_LARGE_IO_PAGES */
547 
548 static unsigned long i460_mask_memory (struct agp_bridge_data *bridge,
549 				       dma_addr_t addr, int type)
550 {
551 	/* Make sure the returned address is a valid GATT entry */
552 	return bridge->driver->masks[0].mask
553 		| (((addr & ~((1 << I460_IO_PAGE_SHIFT) - 1)) & 0xfffff000) >> 12);
554 }
555 
556 const struct agp_bridge_driver intel_i460_driver = {
557 	.owner			= THIS_MODULE,
558 	.aperture_sizes		= i460_sizes,
559 	.size_type		= U8_APER_SIZE,
560 	.num_aperture_sizes	= 3,
561 	.configure		= i460_configure,
562 	.fetch_size		= i460_fetch_size,
563 	.cleanup		= i460_cleanup,
564 	.tlb_flush		= i460_tlb_flush,
565 	.mask_memory		= i460_mask_memory,
566 	.masks			= i460_masks,
567 	.agp_enable		= agp_generic_enable,
568 	.cache_flush		= global_cache_flush,
569 	.create_gatt_table	= i460_create_gatt_table,
570 	.free_gatt_table	= i460_free_gatt_table,
571 #if I460_LARGE_IO_PAGES
572 	.insert_memory		= i460_insert_memory,
573 	.remove_memory		= i460_remove_memory,
574 	.agp_alloc_page		= i460_alloc_page,
575 	.agp_destroy_page	= i460_destroy_page,
576 #else
577 	.insert_memory		= i460_insert_memory_small_io_page,
578 	.remove_memory		= i460_remove_memory_small_io_page,
579 	.agp_alloc_page		= agp_generic_alloc_page,
580 	.agp_alloc_pages	= agp_generic_alloc_pages,
581 	.agp_destroy_page	= agp_generic_destroy_page,
582 	.agp_destroy_pages	= agp_generic_destroy_pages,
583 #endif
584 	.alloc_by_type		= agp_generic_alloc_by_type,
585 	.free_by_type		= agp_generic_free_by_type,
586 	.agp_type_to_mask_type  = agp_generic_type_to_mask_type,
587 	.cant_use_aperture	= true,
588 };
589 
590 static int agp_intel_i460_probe(struct pci_dev *pdev,
591 				const struct pci_device_id *ent)
592 {
593 	struct agp_bridge_data *bridge;
594 	u8 cap_ptr;
595 
596 	cap_ptr = pci_find_capability(pdev, PCI_CAP_ID_AGP);
597 	if (!cap_ptr)
598 		return -ENODEV;
599 
600 	bridge = agp_alloc_bridge();
601 	if (!bridge)
602 		return -ENOMEM;
603 
604 	bridge->driver = &intel_i460_driver;
605 	bridge->dev = pdev;
606 	bridge->capndx = cap_ptr;
607 
608 	printk(KERN_INFO PFX "Detected Intel 460GX chipset\n");
609 
610 	pci_set_drvdata(pdev, bridge);
611 	return agp_add_bridge(bridge);
612 }
613 
614 static void agp_intel_i460_remove(struct pci_dev *pdev)
615 {
616 	struct agp_bridge_data *bridge = pci_get_drvdata(pdev);
617 
618 	agp_remove_bridge(bridge);
619 	agp_put_bridge(bridge);
620 }
621 
622 static struct pci_device_id agp_intel_i460_pci_table[] = {
623 	{
624 	.class		= (PCI_CLASS_BRIDGE_HOST << 8),
625 	.class_mask	= ~0,
626 	.vendor		= PCI_VENDOR_ID_INTEL,
627 	.device		= PCI_DEVICE_ID_INTEL_84460GX,
628 	.subvendor	= PCI_ANY_ID,
629 	.subdevice	= PCI_ANY_ID,
630 	},
631 	{ }
632 };
633 
634 MODULE_DEVICE_TABLE(pci, agp_intel_i460_pci_table);
635 
636 static struct pci_driver agp_intel_i460_pci_driver = {
637 	.name		= "agpgart-intel-i460",
638 	.id_table	= agp_intel_i460_pci_table,
639 	.probe		= agp_intel_i460_probe,
640 	.remove		= agp_intel_i460_remove,
641 };
642 
643 static int __init agp_intel_i460_init(void)
644 {
645 	if (agp_off)
646 		return -EINVAL;
647 	return pci_register_driver(&agp_intel_i460_pci_driver);
648 }
649 
650 static void __exit agp_intel_i460_cleanup(void)
651 {
652 	pci_unregister_driver(&agp_intel_i460_pci_driver);
653 }
654 
655 module_init(agp_intel_i460_init);
656 module_exit(agp_intel_i460_cleanup);
657 
658 MODULE_AUTHOR("Chris Ahna <Christopher.J.Ahna@intel.com>");
659 MODULE_LICENSE("GPL and additional rights");
660