xref: /freebsd/sys/dev/agp/agp.c (revision 2546665afcaf0d53dc2c7058fee96354b3680f5a)
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 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include "opt_bus.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/module.h>
37 #include <sys/bus.h>
38 #include <sys/conf.h>
39 #include <sys/ioccom.h>
40 #include <sys/agpio.h>
41 #include <sys/lock.h>
42 #include <sys/mutex.h>
43 #include <sys/proc.h>
44 
45 #include <dev/pci/pcivar.h>
46 #include <dev/pci/pcireg.h>
47 #include <pci/agppriv.h>
48 #include <pci/agpvar.h>
49 #include <pci/agpreg.h>
50 
51 #include <vm/vm.h>
52 #include <vm/vm_object.h>
53 #include <vm/vm_page.h>
54 #include <vm/vm_pageout.h>
55 #include <vm/pmap.h>
56 
57 #include <machine/md_var.h>
58 #include <machine/bus.h>
59 #include <machine/resource.h>
60 #include <sys/rman.h>
61 
62 MODULE_VERSION(agp, 1);
63 
64 MALLOC_DEFINE(M_AGP, "agp", "AGP data structures");
65 
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 	.d_version =	D_VERSION,
74 	.d_flags =	D_NEEDGIANT,
75 	.d_open =	agp_open,
76 	.d_close =	agp_close,
77 	.d_ioctl =	agp_ioctl,
78 	.d_mmap =	agp_mmap,
79 	.d_name =	"agp",
80 };
81 
82 static devclass_t agp_devclass;
83 #define KDEV2DEV(kdev)	devclass_get_device(agp_devclass, minor(kdev))
84 
85 /* Helper functions for implementing chipset mini drivers. */
86 
87 void
88 agp_flush_cache()
89 {
90 #ifdef __i386__
91 	wbinvd();
92 #endif
93 #ifdef __alpha__
94 	/* FIXME: This is most likely not correct as it doesn't flush CPU
95 	 * write caches, but we don't have a facility to do that and
96 	 * this is all linux does, too */
97 	alpha_mb();
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 	if (entries == 0) {
178 		device_printf(dev, "bad aperture size\n");
179 		return NULL;
180 	}
181 
182 	gatt = malloc(sizeof(struct agp_gatt), M_AGP, M_NOWAIT);
183 	if (!gatt)
184 		return 0;
185 
186 	gatt->ag_entries = entries;
187 	gatt->ag_virtual = contigmalloc(entries * sizeof(u_int32_t), M_AGP, 0,
188 					0, ~0, PAGE_SIZE, 0);
189 	if (!gatt->ag_virtual) {
190 		if (bootverbose)
191 			device_printf(dev, "contiguous allocation failed\n");
192 		free(gatt, M_AGP);
193 		return 0;
194 	}
195 	bzero(gatt->ag_virtual, entries * sizeof(u_int32_t));
196 	gatt->ag_physical = vtophys((vm_offset_t) gatt->ag_virtual);
197 	agp_flush_cache();
198 
199 	return gatt;
200 }
201 
202 void
203 agp_free_gatt(struct agp_gatt *gatt)
204 {
205 	contigfree(gatt->ag_virtual,
206 		   gatt->ag_entries * sizeof(u_int32_t), M_AGP);
207 	free(gatt, M_AGP);
208 }
209 
210 static int agp_max[][2] = {
211 	{0,	0},
212 	{32,	4},
213 	{64,	28},
214 	{128,	96},
215 	{256,	204},
216 	{512,	440},
217 	{1024,	942},
218 	{2048,	1920},
219 	{4096,	3932}
220 };
221 #define agp_max_size	(sizeof(agp_max) / sizeof(agp_max[0]))
222 
223 int
224 agp_generic_attach(device_t dev)
225 {
226 	struct agp_softc *sc = device_get_softc(dev);
227 	int rid, memsize, i;
228 
229 	/*
230 	 * Find and map the aperture.
231 	 */
232 	rid = AGP_APBASE;
233 	sc->as_aperture = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
234 						 RF_ACTIVE);
235 	if (!sc->as_aperture)
236 		return ENOMEM;
237 
238 	/*
239 	 * Work out an upper bound for agp memory allocation. This
240 	 * uses a heurisitc table from the Linux driver.
241 	 */
242 	memsize = ptoa(Maxmem) >> 20;
243 	for (i = 0; i < agp_max_size; i++) {
244 		if (memsize <= agp_max[i][0])
245 			break;
246 	}
247 	if (i == agp_max_size) i = agp_max_size - 1;
248 	sc->as_maxmem = agp_max[i][1] << 20U;
249 
250 	/*
251 	 * The lock is used to prevent re-entry to
252 	 * agp_generic_bind_memory() since that function can sleep.
253 	 */
254 	mtx_init(&sc->as_lock, "agp lock", NULL, MTX_DEF);
255 
256 	/*
257 	 * Initialise stuff for the userland device.
258 	 */
259 	agp_devclass = devclass_find("agp");
260 	TAILQ_INIT(&sc->as_memory);
261 	sc->as_nextid = 1;
262 
263 	sc->as_devnode = make_dev(&agp_cdevsw,
264 				  device_get_unit(dev),
265 				  UID_ROOT,
266 				  GID_WHEEL,
267 				  0600,
268 				  "agpgart");
269 
270 	return 0;
271 }
272 
273 int
274 agp_generic_detach(device_t dev)
275 {
276 	struct agp_softc *sc = device_get_softc(dev);
277 	bus_release_resource(dev, SYS_RES_MEMORY, AGP_APBASE, sc->as_aperture);
278 	mtx_destroy(&sc->as_lock);
279 	destroy_dev(sc->as_devnode);
280 	agp_flush_cache();
281 	return 0;
282 }
283 
284 /*
285  * This does the enable logic for v3, with the same topology
286  * restrictions as in place for v2 -- one bus, one device on the bus.
287  */
288 static int
289 agp_v3_enable(device_t dev, device_t mdev, u_int32_t mode)
290 {
291 	u_int32_t tstatus, mstatus;
292 	u_int32_t command;
293 	int rq, sba, fw, rate, arqsz, cal;
294 
295 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
296 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
297 
298 	/* Set RQ to the min of mode, tstatus and mstatus */
299 	rq = AGP_MODE_GET_RQ(mode);
300 	if (AGP_MODE_GET_RQ(tstatus) < rq)
301 		rq = AGP_MODE_GET_RQ(tstatus);
302 	if (AGP_MODE_GET_RQ(mstatus) < rq)
303 		rq = AGP_MODE_GET_RQ(mstatus);
304 
305 	/*
306 	 * ARQSZ - Set the value to the maximum one.
307 	 * Don't allow the mode register to override values.
308 	 */
309 	arqsz = AGP_MODE_GET_ARQSZ(mode);
310 	if (AGP_MODE_GET_ARQSZ(tstatus) > rq)
311 		rq = AGP_MODE_GET_ARQSZ(tstatus);
312 	if (AGP_MODE_GET_ARQSZ(mstatus) > rq)
313 		rq = AGP_MODE_GET_ARQSZ(mstatus);
314 
315 	/* Calibration cycle - don't allow override by mode register */
316 	cal = AGP_MODE_GET_CAL(tstatus);
317 	if (AGP_MODE_GET_CAL(mstatus) < cal)
318 		cal = AGP_MODE_GET_CAL(mstatus);
319 
320 	/* SBA must be supported for AGP v3. */
321 	sba = 1;
322 
323 	/* Set FW if all three support it. */
324 	fw = (AGP_MODE_GET_FW(tstatus)
325 	       & AGP_MODE_GET_FW(mstatus)
326 	       & AGP_MODE_GET_FW(mode));
327 
328 	/* Figure out the max rate */
329 	rate = (AGP_MODE_GET_RATE(tstatus)
330 		& AGP_MODE_GET_RATE(mstatus)
331 		& AGP_MODE_GET_RATE(mode));
332 	if (rate & AGP_MODE_V3_RATE_8x)
333 		rate = AGP_MODE_V3_RATE_8x;
334 	else
335 		rate = AGP_MODE_V3_RATE_4x;
336 	if (bootverbose)
337 		device_printf(dev, "Setting AGP v3 mode %d\n", rate * 4);
338 
339 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, 0, 4);
340 
341 	/* Construct the new mode word and tell the hardware */
342 	command = AGP_MODE_SET_RQ(0, rq);
343 	command = AGP_MODE_SET_ARQSZ(command, arqsz);
344 	command = AGP_MODE_SET_CAL(command, cal);
345 	command = AGP_MODE_SET_SBA(command, sba);
346 	command = AGP_MODE_SET_FW(command, fw);
347 	command = AGP_MODE_SET_RATE(command, rate);
348 	command = AGP_MODE_SET_AGP(command, 1);
349 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
350 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
351 
352 	return 0;
353 }
354 
355 static int
356 agp_v2_enable(device_t dev, device_t mdev, u_int32_t mode)
357 {
358 	u_int32_t tstatus, mstatus;
359 	u_int32_t command;
360 	int rq, sba, fw, rate;
361 
362 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
363 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
364 
365 	/* Set RQ to the min of mode, tstatus and mstatus */
366 	rq = AGP_MODE_GET_RQ(mode);
367 	if (AGP_MODE_GET_RQ(tstatus) < rq)
368 		rq = AGP_MODE_GET_RQ(tstatus);
369 	if (AGP_MODE_GET_RQ(mstatus) < rq)
370 		rq = AGP_MODE_GET_RQ(mstatus);
371 
372 	/* Set SBA if all three can deal with SBA */
373 	sba = (AGP_MODE_GET_SBA(tstatus)
374 	       & AGP_MODE_GET_SBA(mstatus)
375 	       & AGP_MODE_GET_SBA(mode));
376 
377 	/* Similar for FW */
378 	fw = (AGP_MODE_GET_FW(tstatus)
379 	       & AGP_MODE_GET_FW(mstatus)
380 	       & AGP_MODE_GET_FW(mode));
381 
382 	/* Figure out the max rate */
383 	rate = (AGP_MODE_GET_RATE(tstatus)
384 		& AGP_MODE_GET_RATE(mstatus)
385 		& AGP_MODE_GET_RATE(mode));
386 	if (rate & AGP_MODE_V2_RATE_4x)
387 		rate = AGP_MODE_V2_RATE_4x;
388 	else if (rate & AGP_MODE_V2_RATE_2x)
389 		rate = AGP_MODE_V2_RATE_2x;
390 	else
391 		rate = AGP_MODE_V2_RATE_1x;
392 	if (bootverbose)
393 		device_printf(dev, "Setting AGP v2 mode %d\n", rate);
394 
395 	/* Construct the new mode word and tell the hardware */
396 	command = AGP_MODE_SET_RQ(0, rq);
397 	command = AGP_MODE_SET_SBA(command, sba);
398 	command = AGP_MODE_SET_FW(command, fw);
399 	command = AGP_MODE_SET_RATE(command, rate);
400 	command = AGP_MODE_SET_AGP(command, 1);
401 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
402 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
403 
404 	return 0;
405 }
406 
407 int
408 agp_generic_enable(device_t dev, u_int32_t mode)
409 {
410 	device_t mdev = agp_find_display();
411 	u_int32_t tstatus, mstatus;
412 
413 	if (!mdev) {
414 		AGP_DPF("can't find display\n");
415 		return ENXIO;
416 	}
417 
418 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
419 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
420 
421 	/*
422 	 * Check display and bridge for AGP v3 support.  AGP v3 allows
423 	 * more variety in topology than v2, e.g. multiple AGP devices
424 	 * attached to one bridge, or multiple AGP bridges in one
425 	 * system.  This doesn't attempt to address those situations,
426 	 * but should work fine for a classic single AGP slot system
427 	 * with AGP v3.
428 	 */
429 	if (AGP_MODE_GET_MODE_3(tstatus) && AGP_MODE_GET_MODE_3(mstatus))
430 		return (agp_v3_enable(dev, mdev, mode));
431 	else
432 		return (agp_v2_enable(dev, mdev, mode));
433 }
434 
435 struct agp_memory *
436 agp_generic_alloc_memory(device_t dev, int type, vm_size_t size)
437 {
438 	struct agp_softc *sc = device_get_softc(dev);
439 	struct agp_memory *mem;
440 
441 	if ((size & (AGP_PAGE_SIZE - 1)) != 0)
442 		return 0;
443 
444 	if (sc->as_allocated + size > sc->as_maxmem)
445 		return 0;
446 
447 	if (type != 0) {
448 		printf("agp_generic_alloc_memory: unsupported type %d\n",
449 		       type);
450 		return 0;
451 	}
452 
453 	mem = malloc(sizeof *mem, M_AGP, M_WAITOK);
454 	mem->am_id = sc->as_nextid++;
455 	mem->am_size = size;
456 	mem->am_type = 0;
457 	mem->am_obj = vm_object_allocate(OBJT_DEFAULT, atop(round_page(size)));
458 	mem->am_physical = 0;
459 	mem->am_offset = 0;
460 	mem->am_is_bound = 0;
461 	TAILQ_INSERT_TAIL(&sc->as_memory, mem, am_link);
462 	sc->as_allocated += size;
463 
464 	return mem;
465 }
466 
467 int
468 agp_generic_free_memory(device_t dev, struct agp_memory *mem)
469 {
470 	struct agp_softc *sc = device_get_softc(dev);
471 
472 	if (mem->am_is_bound)
473 		return EBUSY;
474 
475 	sc->as_allocated -= mem->am_size;
476 	TAILQ_REMOVE(&sc->as_memory, mem, am_link);
477 	vm_object_deallocate(mem->am_obj);
478 	free(mem, M_AGP);
479 	return 0;
480 }
481 
482 int
483 agp_generic_bind_memory(device_t dev, struct agp_memory *mem,
484 			vm_offset_t offset)
485 {
486 	struct agp_softc *sc = device_get_softc(dev);
487 	vm_offset_t i, j, k;
488 	vm_page_t m;
489 	int error;
490 
491 	/* Do some sanity checks first. */
492 	if (offset < 0 || (offset & (AGP_PAGE_SIZE - 1)) != 0 ||
493 	    offset + mem->am_size > AGP_GET_APERTURE(dev)) {
494 		device_printf(dev, "binding memory at bad offset %#x\n",
495 		    (int)offset);
496 		return EINVAL;
497 	}
498 
499 	/*
500 	 * Allocate the pages early, before acquiring the lock,
501 	 * because vm_page_grab() used with VM_ALLOC_RETRY may
502 	 * block and we can't hold a mutex while blocking.
503 	 */
504 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
505 		/*
506 		 * Find a page from the object and wire it
507 		 * down. This page will be mapped using one or more
508 		 * entries in the GATT (assuming that PAGE_SIZE >=
509 		 * AGP_PAGE_SIZE. If this is the first call to bind,
510 		 * the pages will be allocated and zeroed.
511 		 */
512 		VM_OBJECT_LOCK(mem->am_obj);
513 		m = vm_page_grab(mem->am_obj, OFF_TO_IDX(i),
514 		    VM_ALLOC_WIRED | VM_ALLOC_ZERO | VM_ALLOC_RETRY);
515 		VM_OBJECT_UNLOCK(mem->am_obj);
516 		AGP_DPF("found page pa=%#x\n", VM_PAGE_TO_PHYS(m));
517 	}
518 
519 	mtx_lock(&sc->as_lock);
520 
521 	if (mem->am_is_bound) {
522 		device_printf(dev, "memory already bound\n");
523 		error = EINVAL;
524 		goto bad;
525 	}
526 
527 	/*
528 	 * Bind the individual pages and flush the chipset's
529 	 * TLB.
530 	 *
531 	 * XXX Presumably, this needs to be the pci address on alpha
532 	 * (i.e. use alpha_XXX_dmamap()). I don't have access to any
533 	 * alpha AGP hardware to check.
534 	 */
535 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
536 		VM_OBJECT_LOCK(mem->am_obj);
537 		m = vm_page_lookup(mem->am_obj, OFF_TO_IDX(i));
538 		VM_OBJECT_UNLOCK(mem->am_obj);
539 
540 		/*
541 		 * Install entries in the GATT, making sure that if
542 		 * AGP_PAGE_SIZE < PAGE_SIZE and mem->am_size is not
543 		 * aligned to PAGE_SIZE, we don't modify too many GATT
544 		 * entries.
545 		 */
546 		for (j = 0; j < PAGE_SIZE && i + j < mem->am_size;
547 		     j += AGP_PAGE_SIZE) {
548 			vm_offset_t pa = VM_PAGE_TO_PHYS(m) + j;
549 			AGP_DPF("binding offset %#x to pa %#x\n",
550 				offset + i + j, pa);
551 			error = AGP_BIND_PAGE(dev, offset + i + j, pa);
552 			if (error) {
553 				/*
554 				 * Bail out. Reverse all the mappings
555 				 * and unwire the pages.
556 				 */
557 				vm_page_lock_queues();
558 				vm_page_wakeup(m);
559 				vm_page_unlock_queues();
560 				for (k = 0; k < i + j; k += AGP_PAGE_SIZE)
561 					AGP_UNBIND_PAGE(dev, offset + k);
562 				goto bad;
563 			}
564 		}
565 		vm_page_lock_queues();
566 		vm_page_wakeup(m);
567 		vm_page_unlock_queues();
568 	}
569 
570 	/*
571 	 * Flush the cpu cache since we are providing a new mapping
572 	 * for these pages.
573 	 */
574 	agp_flush_cache();
575 
576 	/*
577 	 * Make sure the chipset gets the new mappings.
578 	 */
579 	AGP_FLUSH_TLB(dev);
580 
581 	mem->am_offset = offset;
582 	mem->am_is_bound = 1;
583 
584 	mtx_unlock(&sc->as_lock);
585 
586 	return 0;
587 bad:
588 	mtx_unlock(&sc->as_lock);
589 	VM_OBJECT_LOCK(mem->am_obj);
590 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
591 		m = vm_page_lookup(mem->am_obj, OFF_TO_IDX(i));
592 		vm_page_lock_queues();
593 		vm_page_unwire(m, 0);
594 		vm_page_unlock_queues();
595 	}
596 	VM_OBJECT_UNLOCK(mem->am_obj);
597 
598 	return error;
599 }
600 
601 int
602 agp_generic_unbind_memory(device_t dev, struct agp_memory *mem)
603 {
604 	struct agp_softc *sc = device_get_softc(dev);
605 	vm_page_t m;
606 	int i;
607 
608 	mtx_lock(&sc->as_lock);
609 
610 	if (!mem->am_is_bound) {
611 		device_printf(dev, "memory is not bound\n");
612 		mtx_unlock(&sc->as_lock);
613 		return EINVAL;
614 	}
615 
616 
617 	/*
618 	 * Unbind the individual pages and flush the chipset's
619 	 * TLB. Unwire the pages so they can be swapped.
620 	 */
621 	for (i = 0; i < mem->am_size; i += AGP_PAGE_SIZE)
622 		AGP_UNBIND_PAGE(dev, mem->am_offset + i);
623 	VM_OBJECT_LOCK(mem->am_obj);
624 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
625 		m = vm_page_lookup(mem->am_obj, atop(i));
626 		vm_page_lock_queues();
627 		vm_page_unwire(m, 0);
628 		vm_page_unlock_queues();
629 	}
630 	VM_OBJECT_UNLOCK(mem->am_obj);
631 
632 	agp_flush_cache();
633 	AGP_FLUSH_TLB(dev);
634 
635 	mem->am_offset = 0;
636 	mem->am_is_bound = 0;
637 
638 	mtx_unlock(&sc->as_lock);
639 
640 	return 0;
641 }
642 
643 /* Helper functions for implementing user/kernel api */
644 
645 static int
646 agp_acquire_helper(device_t dev, enum agp_acquire_state state)
647 {
648 	struct agp_softc *sc = device_get_softc(dev);
649 
650 	if (sc->as_state != AGP_ACQUIRE_FREE)
651 		return EBUSY;
652 	sc->as_state = state;
653 
654 	return 0;
655 }
656 
657 static int
658 agp_release_helper(device_t dev, enum agp_acquire_state state)
659 {
660 	struct agp_softc *sc = device_get_softc(dev);
661 
662 	if (sc->as_state == AGP_ACQUIRE_FREE)
663 		return 0;
664 
665 	if (sc->as_state != state)
666 		return EBUSY;
667 
668 	sc->as_state = AGP_ACQUIRE_FREE;
669 	return 0;
670 }
671 
672 static struct agp_memory *
673 agp_find_memory(device_t dev, int id)
674 {
675 	struct agp_softc *sc = device_get_softc(dev);
676 	struct agp_memory *mem;
677 
678 	AGP_DPF("searching for memory block %d\n", id);
679 	TAILQ_FOREACH(mem, &sc->as_memory, am_link) {
680 		AGP_DPF("considering memory block %d\n", mem->am_id);
681 		if (mem->am_id == id)
682 			return mem;
683 	}
684 	return 0;
685 }
686 
687 /* Implementation of the userland ioctl api */
688 
689 static int
690 agp_info_user(device_t dev, agp_info *info)
691 {
692 	struct agp_softc *sc = device_get_softc(dev);
693 
694 	bzero(info, sizeof *info);
695 	info->bridge_id = pci_get_devid(dev);
696 	info->agp_mode =
697 	    pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
698 	info->aper_base = rman_get_start(sc->as_aperture);
699 	info->aper_size = AGP_GET_APERTURE(dev) >> 20;
700 	info->pg_total = info->pg_system = sc->as_maxmem >> AGP_PAGE_SHIFT;
701 	info->pg_used = sc->as_allocated >> AGP_PAGE_SHIFT;
702 
703 	return 0;
704 }
705 
706 static int
707 agp_setup_user(device_t dev, agp_setup *setup)
708 {
709 	return AGP_ENABLE(dev, setup->agp_mode);
710 }
711 
712 static int
713 agp_allocate_user(device_t dev, agp_allocate *alloc)
714 {
715 	struct agp_memory *mem;
716 
717 	mem = AGP_ALLOC_MEMORY(dev,
718 			       alloc->type,
719 			       alloc->pg_count << AGP_PAGE_SHIFT);
720 	if (mem) {
721 		alloc->key = mem->am_id;
722 		alloc->physical = mem->am_physical;
723 		return 0;
724 	} else {
725 		return ENOMEM;
726 	}
727 }
728 
729 static int
730 agp_deallocate_user(device_t dev, int id)
731 {
732 	struct agp_memory *mem = agp_find_memory(dev, id);;
733 
734 	if (mem) {
735 		AGP_FREE_MEMORY(dev, mem);
736 		return 0;
737 	} else {
738 		return ENOENT;
739 	}
740 }
741 
742 static int
743 agp_bind_user(device_t dev, agp_bind *bind)
744 {
745 	struct agp_memory *mem = agp_find_memory(dev, bind->key);
746 
747 	if (!mem)
748 		return ENOENT;
749 
750 	return AGP_BIND_MEMORY(dev, mem, bind->pg_start << AGP_PAGE_SHIFT);
751 }
752 
753 static int
754 agp_unbind_user(device_t dev, agp_unbind *unbind)
755 {
756 	struct agp_memory *mem = agp_find_memory(dev, unbind->key);
757 
758 	if (!mem)
759 		return ENOENT;
760 
761 	return AGP_UNBIND_MEMORY(dev, mem);
762 }
763 
764 static int
765 agp_open(struct cdev *kdev, int oflags, int devtype, struct thread *td)
766 {
767 	device_t dev = KDEV2DEV(kdev);
768 	struct agp_softc *sc = device_get_softc(dev);
769 
770 	if (!sc->as_isopen) {
771 		sc->as_isopen = 1;
772 		device_busy(dev);
773 	}
774 
775 	return 0;
776 }
777 
778 static int
779 agp_close(struct cdev *kdev, int fflag, int devtype, struct thread *td)
780 {
781 	device_t dev = KDEV2DEV(kdev);
782 	struct agp_softc *sc = device_get_softc(dev);
783 	struct agp_memory *mem;
784 
785 	/*
786 	 * Clear the GATT and force release on last close
787 	 */
788 	while ((mem = TAILQ_FIRST(&sc->as_memory)) != 0) {
789 		if (mem->am_is_bound)
790 			AGP_UNBIND_MEMORY(dev, mem);
791 		AGP_FREE_MEMORY(dev, mem);
792 	}
793 	if (sc->as_state == AGP_ACQUIRE_USER)
794 		agp_release_helper(dev, AGP_ACQUIRE_USER);
795 	sc->as_isopen = 0;
796 	device_unbusy(dev);
797 
798 	return 0;
799 }
800 
801 static int
802 agp_ioctl(struct cdev *kdev, u_long cmd, caddr_t data, int fflag, struct thread *td)
803 {
804 	device_t dev = KDEV2DEV(kdev);
805 
806 	switch (cmd) {
807 	case AGPIOC_INFO:
808 		return agp_info_user(dev, (agp_info *) data);
809 
810 	case AGPIOC_ACQUIRE:
811 		return agp_acquire_helper(dev, AGP_ACQUIRE_USER);
812 
813 	case AGPIOC_RELEASE:
814 		return agp_release_helper(dev, AGP_ACQUIRE_USER);
815 
816 	case AGPIOC_SETUP:
817 		return agp_setup_user(dev, (agp_setup *)data);
818 
819 	case AGPIOC_ALLOCATE:
820 		return agp_allocate_user(dev, (agp_allocate *)data);
821 
822 	case AGPIOC_DEALLOCATE:
823 		return agp_deallocate_user(dev, *(int *) data);
824 
825 	case AGPIOC_BIND:
826 		return agp_bind_user(dev, (agp_bind *)data);
827 
828 	case AGPIOC_UNBIND:
829 		return agp_unbind_user(dev, (agp_unbind *)data);
830 
831 	}
832 
833 	return EINVAL;
834 }
835 
836 static int
837 agp_mmap(struct cdev *kdev, vm_offset_t offset, vm_paddr_t *paddr, int prot)
838 {
839 	device_t dev = KDEV2DEV(kdev);
840 	struct agp_softc *sc = device_get_softc(dev);
841 
842 	if (offset > AGP_GET_APERTURE(dev))
843 		return -1;
844 	*paddr = rman_get_start(sc->as_aperture) + offset;
845 	return 0;
846 }
847 
848 /* Implementation of the kernel api */
849 
850 device_t
851 agp_find_device()
852 {
853 	if (!agp_devclass)
854 		return 0;
855 	return devclass_get_device(agp_devclass, 0);
856 }
857 
858 enum agp_acquire_state
859 agp_state(device_t dev)
860 {
861 	struct agp_softc *sc = device_get_softc(dev);
862 	return sc->as_state;
863 }
864 
865 void
866 agp_get_info(device_t dev, struct agp_info *info)
867 {
868 	struct agp_softc *sc = device_get_softc(dev);
869 
870 	info->ai_mode =
871 		pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
872 	info->ai_aperture_base = rman_get_start(sc->as_aperture);
873 	info->ai_aperture_size = rman_get_size(sc->as_aperture);
874 	info->ai_aperture_va = (vm_offset_t) rman_get_virtual(sc->as_aperture);
875 	info->ai_memory_allowed = sc->as_maxmem;
876 	info->ai_memory_used = sc->as_allocated;
877 }
878 
879 int
880 agp_acquire(device_t dev)
881 {
882 	return agp_acquire_helper(dev, AGP_ACQUIRE_KERNEL);
883 }
884 
885 int
886 agp_release(device_t dev)
887 {
888 	return agp_release_helper(dev, AGP_ACQUIRE_KERNEL);
889 }
890 
891 int
892 agp_enable(device_t dev, u_int32_t mode)
893 {
894 	return AGP_ENABLE(dev, mode);
895 }
896 
897 void *agp_alloc_memory(device_t dev, int type, vm_size_t bytes)
898 {
899 	return  (void *) AGP_ALLOC_MEMORY(dev, type, bytes);
900 }
901 
902 void agp_free_memory(device_t dev, void *handle)
903 {
904 	struct agp_memory *mem = (struct agp_memory *) handle;
905 	AGP_FREE_MEMORY(dev, mem);
906 }
907 
908 int agp_bind_memory(device_t dev, void *handle, vm_offset_t offset)
909 {
910 	struct agp_memory *mem = (struct agp_memory *) handle;
911 	return AGP_BIND_MEMORY(dev, mem, offset);
912 }
913 
914 int agp_unbind_memory(device_t dev, void *handle)
915 {
916 	struct agp_memory *mem = (struct agp_memory *) handle;
917 	return AGP_UNBIND_MEMORY(dev, mem);
918 }
919 
920 void agp_memory_info(device_t dev, void *handle, struct
921 		     agp_memory_info *mi)
922 {
923 	struct agp_memory *mem = (struct agp_memory *) handle;
924 
925 	mi->ami_size = mem->am_size;
926 	mi->ami_physical = mem->am_physical;
927 	mi->ami_offset = mem->am_offset;
928 	mi->ami_is_bound = mem->am_is_bound;
929 }
930