xref: /freebsd/sys/dev/agp/agp.c (revision 42c159fe388a3765f69860c84183700af37aca8a)
1 /*-
2  * Copyright (c) 2000 Doug Rabson
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  *	$FreeBSD$
27  */
28 
29 #include "opt_bus.h"
30 #include "opt_pci.h"
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/malloc.h>
35 #include <sys/kernel.h>
36 #include <sys/bus.h>
37 #include <sys/conf.h>
38 #include <sys/ioccom.h>
39 #include <sys/agpio.h>
40 #include <sys/lock.h>
41 #include <sys/mutex.h>
42 #include <sys/proc.h>
43 
44 #include <pci/pcivar.h>
45 #include <pci/pcireg.h>
46 #include <pci/agppriv.h>
47 #include <pci/agpvar.h>
48 #include <pci/agpreg.h>
49 
50 #include <vm/vm.h>
51 #include <vm/vm_object.h>
52 #include <vm/vm_page.h>
53 #include <vm/vm_pageout.h>
54 #include <vm/pmap.h>
55 
56 #include <machine/md_var.h>
57 #include <machine/bus.h>
58 #include <machine/resource.h>
59 #include <sys/rman.h>
60 
61 MODULE_VERSION(agp, 1);
62 
63 MALLOC_DEFINE(M_AGP, "agp", "AGP data structures");
64 
65 #define CDEV_MAJOR	148
66 				/* agp_drv.c */
67 static d_open_t agp_open;
68 static d_close_t agp_close;
69 static d_ioctl_t agp_ioctl;
70 static d_mmap_t agp_mmap;
71 
72 static struct cdevsw agp_cdevsw = {
73 	/* open */	agp_open,
74 	/* close */	agp_close,
75 	/* read */	noread,
76 	/* write */	nowrite,
77 	/* ioctl */	agp_ioctl,
78 	/* poll */	nopoll,
79 	/* mmap */	agp_mmap,
80 	/* strategy */	nostrategy,
81 	/* name */	"agp",
82 	/* maj */	CDEV_MAJOR,
83 	/* dump */	nodump,
84 	/* psize */	nopsize,
85 	/* flags */	D_TTY,
86 };
87 
88 static devclass_t agp_devclass;
89 #define KDEV2DEV(kdev)	devclass_get_device(agp_devclass, minor(kdev))
90 
91 /* Helper functions for implementing chipset mini drivers. */
92 
93 void
94 agp_flush_cache()
95 {
96 #ifdef __i386__
97 	wbinvd();
98 #endif
99 }
100 
101 u_int8_t
102 agp_find_caps(device_t dev)
103 {
104 	u_int32_t status;
105 	u_int8_t ptr, next;
106 
107 	/*
108 	 * Check the CAP_LIST bit of the PCI status register first.
109 	 */
110 	status = pci_read_config(dev, PCIR_STATUS, 2);
111 	if (!(status & 0x10))
112 		return 0;
113 
114 	/*
115 	 * Traverse the capabilities list.
116 	 */
117 	for (ptr = pci_read_config(dev, AGP_CAPPTR, 1);
118 	     ptr != 0;
119 	     ptr = next) {
120 		u_int32_t capid = pci_read_config(dev, ptr, 4);
121 		next = AGP_CAPID_GET_NEXT_PTR(capid);
122 
123 		/*
124 		 * If this capability entry ID is 2, then we are done.
125 		 */
126 		if (AGP_CAPID_GET_CAP_ID(capid) == 2)
127 			return ptr;
128 	}
129 
130 	return 0;
131 }
132 
133 /*
134  * Find an AGP display device (if any).
135  */
136 static device_t
137 agp_find_display(void)
138 {
139 	devclass_t pci = devclass_find("pci");
140 	device_t bus, dev = 0;
141 	device_t *kids;
142 	int busnum, numkids, i;
143 
144 	for (busnum = 0; busnum < devclass_get_maxunit(pci); busnum++) {
145 		bus = devclass_get_device(pci, busnum);
146 		if (!bus)
147 			continue;
148 		device_get_children(bus, &kids, &numkids);
149 		for (i = 0; i < numkids; i++) {
150 			dev = kids[i];
151 			if (pci_get_class(dev) == PCIC_DISPLAY
152 			    && pci_get_subclass(dev) == PCIS_DISPLAY_VGA)
153 				if (agp_find_caps(dev)) {
154 					free(kids, M_TEMP);
155 					return dev;
156 				}
157 
158 		}
159 		free(kids, M_TEMP);
160 	}
161 
162 	return 0;
163 }
164 
165 struct agp_gatt *
166 agp_alloc_gatt(device_t dev)
167 {
168 	u_int32_t apsize = AGP_GET_APERTURE(dev);
169 	u_int32_t entries = apsize >> AGP_PAGE_SHIFT;
170 	struct agp_gatt *gatt;
171 
172 	if (bootverbose)
173 		device_printf(dev,
174 			      "allocating GATT for aperture of size %dM\n",
175 			      apsize / (1024*1024));
176 
177 	gatt = malloc(sizeof(struct agp_gatt), M_AGP, M_NOWAIT);
178 	if (!gatt)
179 		return 0;
180 
181 	gatt->ag_entries = entries;
182 	gatt->ag_virtual = contigmalloc(entries * sizeof(u_int32_t), M_AGP, 0,
183 					0, ~0, PAGE_SIZE, 0);
184 	if (!gatt->ag_virtual) {
185 		if (bootverbose)
186 			device_printf(dev, "contiguous allocation failed\n");
187 		free(gatt, M_AGP);
188 		return 0;
189 	}
190 	bzero(gatt->ag_virtual, entries * sizeof(u_int32_t));
191 	gatt->ag_physical = vtophys((vm_offset_t) gatt->ag_virtual);
192 	agp_flush_cache();
193 
194 	return gatt;
195 }
196 
197 void
198 agp_free_gatt(struct agp_gatt *gatt)
199 {
200 	contigfree(gatt->ag_virtual,
201 		   gatt->ag_entries * sizeof(u_int32_t), M_AGP);
202 	free(gatt, M_AGP);
203 }
204 
205 static int agp_max[][2] = {
206 	{0,	0},
207 	{32,	4},
208 	{64,	28},
209 	{128,	96},
210 	{256,	204},
211 	{512,	440},
212 	{1024,	942},
213 	{2048,	1920},
214 	{4096,	3932}
215 };
216 #define agp_max_size	(sizeof(agp_max) / sizeof(agp_max[0]))
217 
218 int
219 agp_generic_attach(device_t dev)
220 {
221 	struct agp_softc *sc = device_get_softc(dev);
222 	int rid, memsize, i;
223 
224 	/*
225 	 * Find and map the aperture.
226 	 */
227 	rid = AGP_APBASE;
228 	sc->as_aperture = bus_alloc_resource(dev, SYS_RES_MEMORY, &rid,
229 					     0, ~0, 1, RF_ACTIVE);
230 	if (!sc->as_aperture)
231 		return ENOMEM;
232 
233 	/*
234 	 * Work out an upper bound for agp memory allocation. This
235 	 * uses a heurisitc table from the Linux driver.
236 	 */
237 	memsize = ptoa(Maxmem) >> 20;
238 	for (i = 0; i < agp_max_size; i++) {
239 		if (memsize <= agp_max[i][0])
240 			break;
241 	}
242 	if (i == agp_max_size) i = agp_max_size - 1;
243 	sc->as_maxmem = agp_max[i][1] << 20U;
244 
245 	/*
246 	 * The lock is used to prevent re-entry to
247 	 * agp_generic_bind_memory() since that function can sleep.
248 	 */
249 	lockinit(&sc->as_lock, PZERO|PCATCH, "agplk", 0, 0);
250 
251 	/*
252 	 * Initialise stuff for the userland device.
253 	 */
254 	agp_devclass = devclass_find("agp");
255 	TAILQ_INIT(&sc->as_memory);
256 	sc->as_nextid = 1;
257 
258 	sc->as_devnode = make_dev(&agp_cdevsw,
259 				  device_get_unit(dev),
260 				  UID_ROOT,
261 				  GID_WHEEL,
262 				  0600,
263 				  "agpgart");
264 
265 	return 0;
266 }
267 
268 int
269 agp_generic_detach(device_t dev)
270 {
271 	struct agp_softc *sc = device_get_softc(dev);
272 	bus_release_resource(dev, SYS_RES_MEMORY, AGP_APBASE, sc->as_aperture);
273 	lockmgr(&sc->as_lock, LK_DRAIN, 0, curthread);
274 	lockdestroy(&sc->as_lock);
275 	destroy_dev(sc->as_devnode);
276 	agp_flush_cache();
277 	return 0;
278 }
279 
280 int
281 agp_generic_enable(device_t dev, u_int32_t mode)
282 {
283 	device_t mdev = agp_find_display();
284 	u_int32_t tstatus, mstatus;
285 	u_int32_t command;
286 	int rq, sba, fw, rate;;
287 
288 	if (!mdev) {
289 		AGP_DPF("can't find display\n");
290 		return ENXIO;
291 	}
292 
293 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
294 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
295 
296 	/* Set RQ to the min of mode, tstatus and mstatus */
297 	rq = AGP_MODE_GET_RQ(mode);
298 	if (AGP_MODE_GET_RQ(tstatus) < rq)
299 		rq = AGP_MODE_GET_RQ(tstatus);
300 	if (AGP_MODE_GET_RQ(mstatus) < rq)
301 		rq = AGP_MODE_GET_RQ(mstatus);
302 
303 	/* Set SBA if all three can deal with SBA */
304 	sba = (AGP_MODE_GET_SBA(tstatus)
305 	       & AGP_MODE_GET_SBA(mstatus)
306 	       & AGP_MODE_GET_SBA(mode));
307 
308 	/* Similar for FW */
309 	fw = (AGP_MODE_GET_FW(tstatus)
310 	       & AGP_MODE_GET_FW(mstatus)
311 	       & AGP_MODE_GET_FW(mode));
312 
313 	/* Figure out the max rate */
314 	rate = (AGP_MODE_GET_RATE(tstatus)
315 		& AGP_MODE_GET_RATE(mstatus)
316 		& AGP_MODE_GET_RATE(mode));
317 	if (rate & AGP_MODE_RATE_4x)
318 		rate = AGP_MODE_RATE_4x;
319 	else if (rate & AGP_MODE_RATE_2x)
320 		rate = AGP_MODE_RATE_2x;
321 	else
322 		rate = AGP_MODE_RATE_1x;
323 
324 	/* Construct the new mode word and tell the hardware */
325 	command = AGP_MODE_SET_RQ(0, rq);
326 	command = AGP_MODE_SET_SBA(command, sba);
327 	command = AGP_MODE_SET_FW(command, fw);
328 	command = AGP_MODE_SET_RATE(command, rate);
329 	command = AGP_MODE_SET_AGP(command, 1);
330 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
331 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
332 
333 	return 0;
334 }
335 
336 struct agp_memory *
337 agp_generic_alloc_memory(device_t dev, int type, vm_size_t size)
338 {
339 	struct agp_softc *sc = device_get_softc(dev);
340 	struct agp_memory *mem;
341 
342 	if ((size & (AGP_PAGE_SIZE - 1)) != 0)
343 		return 0;
344 
345 	if (sc->as_allocated + size > sc->as_maxmem)
346 		return 0;
347 
348 	if (type != 0) {
349 		printf("agp_generic_alloc_memory: unsupported type %d\n",
350 		       type);
351 		return 0;
352 	}
353 
354 	mem = malloc(sizeof *mem, M_AGP, M_WAITOK);
355 	mem->am_id = sc->as_nextid++;
356 	mem->am_size = size;
357 	mem->am_type = 0;
358 	mem->am_obj = vm_object_allocate(OBJT_DEFAULT, atop(round_page(size)));
359 	mem->am_physical = 0;
360 	mem->am_offset = 0;
361 	mem->am_is_bound = 0;
362 	TAILQ_INSERT_TAIL(&sc->as_memory, mem, am_link);
363 	sc->as_allocated += size;
364 
365 	return mem;
366 }
367 
368 int
369 agp_generic_free_memory(device_t dev, struct agp_memory *mem)
370 {
371 	struct agp_softc *sc = device_get_softc(dev);
372 
373 	if (mem->am_is_bound)
374 		return EBUSY;
375 
376 	sc->as_allocated -= mem->am_size;
377 	TAILQ_REMOVE(&sc->as_memory, mem, am_link);
378 	vm_object_deallocate(mem->am_obj);
379 	free(mem, M_AGP);
380 	return 0;
381 }
382 
383 int
384 agp_generic_bind_memory(device_t dev, struct agp_memory *mem,
385 			vm_offset_t offset)
386 {
387 	struct agp_softc *sc = device_get_softc(dev);
388 	vm_offset_t i, j, k;
389 	vm_page_t m;
390 	int error;
391 
392 	lockmgr(&sc->as_lock, LK_EXCLUSIVE, 0, curthread);
393 
394 	if (mem->am_is_bound) {
395 		device_printf(dev, "memory already bound\n");
396 		return EINVAL;
397 	}
398 
399 	if (offset < 0
400 	    || (offset & (AGP_PAGE_SIZE - 1)) != 0
401 	    || offset + mem->am_size > AGP_GET_APERTURE(dev)) {
402 		device_printf(dev, "binding memory at bad offset %#x\n",
403 			      (int) offset);
404 		return EINVAL;
405 	}
406 
407 	/*
408 	 * Bind the individual pages and flush the chipset's
409 	 * TLB.
410 	 *
411 	 * XXX Presumably, this needs to be the pci address on alpha
412 	 * (i.e. use alpha_XXX_dmamap()). I don't have access to any
413 	 * alpha AGP hardware to check.
414 	 */
415 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
416 		/*
417 		 * Find a page from the object and wire it
418 		 * down. This page will be mapped using one or more
419 		 * entries in the GATT (assuming that PAGE_SIZE >=
420 		 * AGP_PAGE_SIZE. If this is the first call to bind,
421 		 * the pages will be allocated and zeroed.
422 		 */
423 		m = vm_page_grab(mem->am_obj, OFF_TO_IDX(i),
424 				 VM_ALLOC_ZERO | VM_ALLOC_RETRY);
425 		AGP_DPF("found page pa=%#x\n", VM_PAGE_TO_PHYS(m));
426 		vm_page_wire(m);
427 
428 		/*
429 		 * Install entries in the GATT, making sure that if
430 		 * AGP_PAGE_SIZE < PAGE_SIZE and mem->am_size is not
431 		 * aligned to PAGE_SIZE, we don't modify too many GATT
432 		 * entries.
433 		 */
434 		for (j = 0; j < PAGE_SIZE && i + j < mem->am_size;
435 		     j += AGP_PAGE_SIZE) {
436 			vm_offset_t pa = VM_PAGE_TO_PHYS(m) + j;
437 			AGP_DPF("binding offset %#x to pa %#x\n",
438 				offset + i + j, pa);
439 			error = AGP_BIND_PAGE(dev, offset + i + j, pa);
440 			if (error) {
441 				/*
442 				 * Bail out. Reverse all the mappings
443 				 * and unwire the pages.
444 				 */
445 				vm_page_wakeup(m);
446 				for (k = 0; k < i + j; k += AGP_PAGE_SIZE)
447 					AGP_UNBIND_PAGE(dev, offset + k);
448 				for (k = 0; k <= i; k += PAGE_SIZE) {
449 					m = vm_page_lookup(mem->am_obj,
450 							   OFF_TO_IDX(k));
451 					vm_page_unwire(m, 0);
452 				}
453 				lockmgr(&sc->as_lock, LK_RELEASE, 0, curthread);
454 				return error;
455 			}
456 		}
457 		vm_page_wakeup(m);
458 	}
459 
460 	/*
461 	 * Flush the cpu cache since we are providing a new mapping
462 	 * for these pages.
463 	 */
464 	agp_flush_cache();
465 
466 	/*
467 	 * Make sure the chipset gets the new mappings.
468 	 */
469 	AGP_FLUSH_TLB(dev);
470 
471 	mem->am_offset = offset;
472 	mem->am_is_bound = 1;
473 
474 	lockmgr(&sc->as_lock, LK_RELEASE, 0, curthread);
475 
476 	return 0;
477 }
478 
479 int
480 agp_generic_unbind_memory(device_t dev, struct agp_memory *mem)
481 {
482 	struct agp_softc *sc = device_get_softc(dev);
483 	vm_page_t m;
484 	int i;
485 
486 	lockmgr(&sc->as_lock, LK_EXCLUSIVE, 0, curthread);
487 
488 	if (!mem->am_is_bound) {
489 		device_printf(dev, "memory is not bound\n");
490 		return EINVAL;
491 	}
492 
493 
494 	/*
495 	 * Unbind the individual pages and flush the chipset's
496 	 * TLB. Unwire the pages so they can be swapped.
497 	 */
498 	for (i = 0; i < mem->am_size; i += AGP_PAGE_SIZE)
499 		AGP_UNBIND_PAGE(dev, mem->am_offset + i);
500 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
501 		m = vm_page_lookup(mem->am_obj, atop(i));
502 		vm_page_unwire(m, 0);
503 	}
504 
505 	agp_flush_cache();
506 	AGP_FLUSH_TLB(dev);
507 
508 	mem->am_offset = 0;
509 	mem->am_is_bound = 0;
510 
511 	lockmgr(&sc->as_lock, LK_RELEASE, 0, curthread);
512 
513 	return 0;
514 }
515 
516 /* Helper functions for implementing user/kernel api */
517 
518 static int
519 agp_acquire_helper(device_t dev, enum agp_acquire_state state)
520 {
521 	struct agp_softc *sc = device_get_softc(dev);
522 
523 	if (sc->as_state != AGP_ACQUIRE_FREE)
524 		return EBUSY;
525 	sc->as_state = state;
526 
527 	return 0;
528 }
529 
530 static int
531 agp_release_helper(device_t dev, enum agp_acquire_state state)
532 {
533 	struct agp_softc *sc = device_get_softc(dev);
534 
535 	if (sc->as_state == AGP_ACQUIRE_FREE)
536 		return 0;
537 
538 	if (sc->as_state != state)
539 		return EBUSY;
540 
541 	sc->as_state = AGP_ACQUIRE_FREE;
542 	return 0;
543 }
544 
545 static struct agp_memory *
546 agp_find_memory(device_t dev, int id)
547 {
548 	struct agp_softc *sc = device_get_softc(dev);
549 	struct agp_memory *mem;
550 
551 	AGP_DPF("searching for memory block %d\n", id);
552 	TAILQ_FOREACH(mem, &sc->as_memory, am_link) {
553 		AGP_DPF("considering memory block %d\n", mem->am_id);
554 		if (mem->am_id == id)
555 			return mem;
556 	}
557 	return 0;
558 }
559 
560 /* Implementation of the userland ioctl api */
561 
562 static int
563 agp_info_user(device_t dev, agp_info *info)
564 {
565 	struct agp_softc *sc = device_get_softc(dev);
566 
567 	bzero(info, sizeof *info);
568 	info->bridge_id = pci_get_devid(dev);
569 	info->agp_mode =
570 	    pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
571 	info->aper_base = rman_get_start(sc->as_aperture);
572 	info->aper_size = AGP_GET_APERTURE(dev) >> 20;
573 	info->pg_total = info->pg_system = sc->as_maxmem >> AGP_PAGE_SHIFT;
574 	info->pg_used = sc->as_allocated >> AGP_PAGE_SHIFT;
575 
576 	return 0;
577 }
578 
579 static int
580 agp_setup_user(device_t dev, agp_setup *setup)
581 {
582 	return AGP_ENABLE(dev, setup->agp_mode);
583 }
584 
585 static int
586 agp_allocate_user(device_t dev, agp_allocate *alloc)
587 {
588 	struct agp_memory *mem;
589 
590 	mem = AGP_ALLOC_MEMORY(dev,
591 			       alloc->type,
592 			       alloc->pg_count << AGP_PAGE_SHIFT);
593 	if (mem) {
594 		alloc->key = mem->am_id;
595 		alloc->physical = mem->am_physical;
596 		return 0;
597 	} else {
598 		return ENOMEM;
599 	}
600 }
601 
602 static int
603 agp_deallocate_user(device_t dev, int id)
604 {
605 	struct agp_memory *mem = agp_find_memory(dev, id);;
606 
607 	if (mem) {
608 		AGP_FREE_MEMORY(dev, mem);
609 		return 0;
610 	} else {
611 		return ENOENT;
612 	}
613 }
614 
615 static int
616 agp_bind_user(device_t dev, agp_bind *bind)
617 {
618 	struct agp_memory *mem = agp_find_memory(dev, bind->key);
619 
620 	if (!mem)
621 		return ENOENT;
622 
623 	return AGP_BIND_MEMORY(dev, mem, bind->pg_start << AGP_PAGE_SHIFT);
624 }
625 
626 static int
627 agp_unbind_user(device_t dev, agp_unbind *unbind)
628 {
629 	struct agp_memory *mem = agp_find_memory(dev, unbind->key);
630 
631 	if (!mem)
632 		return ENOENT;
633 
634 	return AGP_UNBIND_MEMORY(dev, mem);
635 }
636 
637 static int
638 agp_open(dev_t kdev, int oflags, int devtype, struct thread *td)
639 {
640 	device_t dev = KDEV2DEV(kdev);
641 	struct agp_softc *sc = device_get_softc(dev);
642 
643 	if (!sc->as_isopen) {
644 		sc->as_isopen = 1;
645 		device_busy(dev);
646 	}
647 
648 	return 0;
649 }
650 
651 static int
652 agp_close(dev_t kdev, int fflag, int devtype, struct thread *td)
653 {
654 	device_t dev = KDEV2DEV(kdev);
655 	struct agp_softc *sc = device_get_softc(dev);
656 	struct agp_memory *mem;
657 
658 	/*
659 	 * Clear the GATT and force release on last close
660 	 */
661 	while ((mem = TAILQ_FIRST(&sc->as_memory)) != 0) {
662 		if (mem->am_is_bound)
663 			AGP_UNBIND_MEMORY(dev, mem);
664 		AGP_FREE_MEMORY(dev, mem);
665 	}
666 	if (sc->as_state == AGP_ACQUIRE_USER)
667 		agp_release_helper(dev, AGP_ACQUIRE_USER);
668 	sc->as_isopen = 0;
669 	device_unbusy(dev);
670 
671 	return 0;
672 }
673 
674 static int
675 agp_ioctl(dev_t kdev, u_long cmd, caddr_t data, int fflag, struct thread *td)
676 {
677 	device_t dev = KDEV2DEV(kdev);
678 
679 	switch (cmd) {
680 	case AGPIOC_INFO:
681 		return agp_info_user(dev, (agp_info *) data);
682 
683 	case AGPIOC_ACQUIRE:
684 		return agp_acquire_helper(dev, AGP_ACQUIRE_USER);
685 
686 	case AGPIOC_RELEASE:
687 		return agp_release_helper(dev, AGP_ACQUIRE_USER);
688 
689 	case AGPIOC_SETUP:
690 		return agp_setup_user(dev, (agp_setup *)data);
691 
692 	case AGPIOC_ALLOCATE:
693 		return agp_allocate_user(dev, (agp_allocate *)data);
694 
695 	case AGPIOC_DEALLOCATE:
696 		return agp_deallocate_user(dev, *(int *) data);
697 
698 	case AGPIOC_BIND:
699 		return agp_bind_user(dev, (agp_bind *)data);
700 
701 	case AGPIOC_UNBIND:
702 		return agp_unbind_user(dev, (agp_unbind *)data);
703 
704 	}
705 
706 	return EINVAL;
707 }
708 
709 static int
710 agp_mmap(dev_t kdev, vm_offset_t offset, int prot)
711 {
712 	device_t dev = KDEV2DEV(kdev);
713 	struct agp_softc *sc = device_get_softc(dev);
714 
715 	if (offset > AGP_GET_APERTURE(dev))
716 		return -1;
717 	return atop(rman_get_start(sc->as_aperture) + offset);
718 }
719 
720 /* Implementation of the kernel api */
721 
722 device_t
723 agp_find_device()
724 {
725 	if (!agp_devclass)
726 		return 0;
727 	return devclass_get_device(agp_devclass, 0);
728 }
729 
730 enum agp_acquire_state
731 agp_state(device_t dev)
732 {
733 	struct agp_softc *sc = device_get_softc(dev);
734 	return sc->as_state;
735 }
736 
737 void
738 agp_get_info(device_t dev, struct agp_info *info)
739 {
740 	struct agp_softc *sc = device_get_softc(dev);
741 
742 	info->ai_mode =
743 		pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
744 	info->ai_aperture_base = rman_get_start(sc->as_aperture);
745 	info->ai_aperture_size = rman_get_size(sc->as_aperture);
746 	info->ai_aperture_va = (vm_offset_t) rman_get_virtual(sc->as_aperture);
747 	info->ai_memory_allowed = sc->as_maxmem;
748 	info->ai_memory_used = sc->as_allocated;
749 }
750 
751 int
752 agp_acquire(device_t dev)
753 {
754 	return agp_acquire_helper(dev, AGP_ACQUIRE_KERNEL);
755 }
756 
757 int
758 agp_release(device_t dev)
759 {
760 	return agp_release_helper(dev, AGP_ACQUIRE_KERNEL);
761 }
762 
763 int
764 agp_enable(device_t dev, u_int32_t mode)
765 {
766 	return AGP_ENABLE(dev, mode);
767 }
768 
769 void *agp_alloc_memory(device_t dev, int type, vm_size_t bytes)
770 {
771 	return  (void *) AGP_ALLOC_MEMORY(dev, type, bytes);
772 }
773 
774 void agp_free_memory(device_t dev, void *handle)
775 {
776 	struct agp_memory *mem = (struct agp_memory *) handle;
777 	AGP_FREE_MEMORY(dev, mem);
778 }
779 
780 int agp_bind_memory(device_t dev, void *handle, vm_offset_t offset)
781 {
782 	struct agp_memory *mem = (struct agp_memory *) handle;
783 	return AGP_BIND_MEMORY(dev, mem, offset);
784 }
785 
786 int agp_unbind_memory(device_t dev, void *handle)
787 {
788 	struct agp_memory *mem = (struct agp_memory *) handle;
789 	return AGP_UNBIND_MEMORY(dev, mem);
790 }
791 
792 void agp_memory_info(device_t dev, void *handle, struct
793 		     agp_memory_info *mi)
794 {
795 	struct agp_memory *mem = (struct agp_memory *) handle;
796 
797 	mi->ami_size = mem->am_size;
798 	mi->ami_physical = mem->am_physical;
799 	mi->ami_offset = mem->am_offset;
800 	mi->ami_is_bound = mem->am_is_bound;
801 }
802