xref: /freebsd/sys/dev/agp/agp.c (revision d2387d42b8da231a5b95cbc313825fb2aadf26f6)
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/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/lockmgr.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 	lockinit(&sc->as_lock, PZERO|PCATCH, "agplk", 0, 0);
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 	lockmgr(&sc->as_lock, LK_DRAIN, 0, curthread);
279 	lockdestroy(&sc->as_lock);
280 	destroy_dev(sc->as_devnode);
281 	agp_flush_cache();
282 	return 0;
283 }
284 
285 /*
286  * This does the enable logic for v3, with the same topology
287  * restrictions as in place for v2 -- one bus, one device on the bus.
288  */
289 static int
290 agp_v3_enable(device_t dev, device_t mdev, u_int32_t mode)
291 {
292 	u_int32_t tstatus, mstatus;
293 	u_int32_t command;
294 	int rq, sba, fw, rate, arqsz, cal;
295 
296 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
297 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
298 
299 	/* Set RQ to the min of mode, tstatus and mstatus */
300 	rq = AGP_MODE_GET_RQ(mode);
301 	if (AGP_MODE_GET_RQ(tstatus) < rq)
302 		rq = AGP_MODE_GET_RQ(tstatus);
303 	if (AGP_MODE_GET_RQ(mstatus) < rq)
304 		rq = AGP_MODE_GET_RQ(mstatus);
305 
306 	/*
307 	 * ARQSZ - Set the value to the maximum one.
308 	 * Don't allow the mode register to override values.
309 	 */
310 	arqsz = AGP_MODE_GET_ARQSZ(mode);
311 	if (AGP_MODE_GET_ARQSZ(tstatus) > rq)
312 		rq = AGP_MODE_GET_ARQSZ(tstatus);
313 	if (AGP_MODE_GET_ARQSZ(mstatus) > rq)
314 		rq = AGP_MODE_GET_ARQSZ(mstatus);
315 
316 	/* Calibration cycle - don't allow override by mode register */
317 	cal = AGP_MODE_GET_CAL(tstatus);
318 	if (AGP_MODE_GET_CAL(mstatus) < cal)
319 		cal = AGP_MODE_GET_CAL(mstatus);
320 
321 	/* SBA must be supported for AGP v3. */
322 	sba = 1;
323 
324 	/* Set FW if all three support it. */
325 	fw = (AGP_MODE_GET_FW(tstatus)
326 	       & AGP_MODE_GET_FW(mstatus)
327 	       & AGP_MODE_GET_FW(mode));
328 
329 	/* Figure out the max rate */
330 	rate = (AGP_MODE_GET_RATE(tstatus)
331 		& AGP_MODE_GET_RATE(mstatus)
332 		& AGP_MODE_GET_RATE(mode));
333 	if (rate & AGP_MODE_V3_RATE_8x)
334 		rate = AGP_MODE_V3_RATE_8x;
335 	else
336 		rate = AGP_MODE_V3_RATE_4x;
337 	if (bootverbose)
338 		device_printf(dev, "Setting AGP v3 mode %d\n", rate * 4);
339 
340 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, 0, 4);
341 
342 	/* Construct the new mode word and tell the hardware */
343 	command = AGP_MODE_SET_RQ(0, rq);
344 	command = AGP_MODE_SET_ARQSZ(command, arqsz);
345 	command = AGP_MODE_SET_CAL(command, cal);
346 	command = AGP_MODE_SET_SBA(command, sba);
347 	command = AGP_MODE_SET_FW(command, fw);
348 	command = AGP_MODE_SET_RATE(command, rate);
349 	command = AGP_MODE_SET_AGP(command, 1);
350 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
351 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
352 
353 	return 0;
354 }
355 
356 static int
357 agp_v2_enable(device_t dev, device_t mdev, u_int32_t mode)
358 {
359 	u_int32_t tstatus, mstatus;
360 	u_int32_t command;
361 	int rq, sba, fw, rate;
362 
363 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
364 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
365 
366 	/* Set RQ to the min of mode, tstatus and mstatus */
367 	rq = AGP_MODE_GET_RQ(mode);
368 	if (AGP_MODE_GET_RQ(tstatus) < rq)
369 		rq = AGP_MODE_GET_RQ(tstatus);
370 	if (AGP_MODE_GET_RQ(mstatus) < rq)
371 		rq = AGP_MODE_GET_RQ(mstatus);
372 
373 	/* Set SBA if all three can deal with SBA */
374 	sba = (AGP_MODE_GET_SBA(tstatus)
375 	       & AGP_MODE_GET_SBA(mstatus)
376 	       & AGP_MODE_GET_SBA(mode));
377 
378 	/* Similar for FW */
379 	fw = (AGP_MODE_GET_FW(tstatus)
380 	       & AGP_MODE_GET_FW(mstatus)
381 	       & AGP_MODE_GET_FW(mode));
382 
383 	/* Figure out the max rate */
384 	rate = (AGP_MODE_GET_RATE(tstatus)
385 		& AGP_MODE_GET_RATE(mstatus)
386 		& AGP_MODE_GET_RATE(mode));
387 	if (rate & AGP_MODE_V2_RATE_4x)
388 		rate = AGP_MODE_V2_RATE_4x;
389 	else if (rate & AGP_MODE_V2_RATE_2x)
390 		rate = AGP_MODE_V2_RATE_2x;
391 	else
392 		rate = AGP_MODE_V2_RATE_1x;
393 	if (bootverbose)
394 		device_printf(dev, "Setting AGP v2 mode %d\n", rate);
395 
396 	/* Construct the new mode word and tell the hardware */
397 	command = AGP_MODE_SET_RQ(0, rq);
398 	command = AGP_MODE_SET_SBA(command, sba);
399 	command = AGP_MODE_SET_FW(command, fw);
400 	command = AGP_MODE_SET_RATE(command, rate);
401 	command = AGP_MODE_SET_AGP(command, 1);
402 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
403 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
404 
405 	return 0;
406 }
407 
408 int
409 agp_generic_enable(device_t dev, u_int32_t mode)
410 {
411 	device_t mdev = agp_find_display();
412 	u_int32_t tstatus, mstatus;
413 
414 	if (!mdev) {
415 		AGP_DPF("can't find display\n");
416 		return ENXIO;
417 	}
418 
419 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
420 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
421 
422 	/*
423 	 * Check display and bridge for AGP v3 support.  AGP v3 allows
424 	 * more variety in topology than v2, e.g. multiple AGP devices
425 	 * attached to one bridge, or multiple AGP bridges in one
426 	 * system.  This doesn't attempt to address those situations,
427 	 * but should work fine for a classic single AGP slot system
428 	 * with AGP v3.
429 	 */
430 	if (AGP_MODE_GET_MODE_3(tstatus) && AGP_MODE_GET_MODE_3(mstatus))
431 		return (agp_v3_enable(dev, mdev, mode));
432 	else
433 		return (agp_v2_enable(dev, mdev, mode));
434 }
435 
436 struct agp_memory *
437 agp_generic_alloc_memory(device_t dev, int type, vm_size_t size)
438 {
439 	struct agp_softc *sc = device_get_softc(dev);
440 	struct agp_memory *mem;
441 
442 	if ((size & (AGP_PAGE_SIZE - 1)) != 0)
443 		return 0;
444 
445 	if (sc->as_allocated + size > sc->as_maxmem)
446 		return 0;
447 
448 	if (type != 0) {
449 		printf("agp_generic_alloc_memory: unsupported type %d\n",
450 		       type);
451 		return 0;
452 	}
453 
454 	mem = malloc(sizeof *mem, M_AGP, M_WAITOK);
455 	mem->am_id = sc->as_nextid++;
456 	mem->am_size = size;
457 	mem->am_type = 0;
458 	mem->am_obj = vm_object_allocate(OBJT_DEFAULT, atop(round_page(size)));
459 	mem->am_physical = 0;
460 	mem->am_offset = 0;
461 	mem->am_is_bound = 0;
462 	TAILQ_INSERT_TAIL(&sc->as_memory, mem, am_link);
463 	sc->as_allocated += size;
464 
465 	return mem;
466 }
467 
468 int
469 agp_generic_free_memory(device_t dev, struct agp_memory *mem)
470 {
471 	struct agp_softc *sc = device_get_softc(dev);
472 
473 	if (mem->am_is_bound)
474 		return EBUSY;
475 
476 	sc->as_allocated -= mem->am_size;
477 	TAILQ_REMOVE(&sc->as_memory, mem, am_link);
478 	vm_object_deallocate(mem->am_obj);
479 	free(mem, M_AGP);
480 	return 0;
481 }
482 
483 int
484 agp_generic_bind_memory(device_t dev, struct agp_memory *mem,
485 			vm_offset_t offset)
486 {
487 	struct agp_softc *sc = device_get_softc(dev);
488 	vm_offset_t i, j, k;
489 	vm_page_t m;
490 	int error;
491 
492 	lockmgr(&sc->as_lock, LK_EXCLUSIVE, 0, curthread);
493 
494 	if (mem->am_is_bound) {
495 		device_printf(dev, "memory already bound\n");
496 		return EINVAL;
497 	}
498 
499 	if (offset < 0
500 	    || (offset & (AGP_PAGE_SIZE - 1)) != 0
501 	    || offset + mem->am_size > AGP_GET_APERTURE(dev)) {
502 		device_printf(dev, "binding memory at bad offset %#x\n",
503 			      (int) offset);
504 		return EINVAL;
505 	}
506 
507 	/*
508 	 * Bind the individual pages and flush the chipset's
509 	 * TLB.
510 	 *
511 	 * XXX Presumably, this needs to be the pci address on alpha
512 	 * (i.e. use alpha_XXX_dmamap()). I don't have access to any
513 	 * alpha AGP hardware to check.
514 	 */
515 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
516 		/*
517 		 * Find a page from the object and wire it
518 		 * down. This page will be mapped using one or more
519 		 * entries in the GATT (assuming that PAGE_SIZE >=
520 		 * AGP_PAGE_SIZE. If this is the first call to bind,
521 		 * the pages will be allocated and zeroed.
522 		 */
523 		VM_OBJECT_LOCK(mem->am_obj);
524 		m = vm_page_grab(mem->am_obj, OFF_TO_IDX(i),
525 		    VM_ALLOC_WIRED | VM_ALLOC_ZERO | VM_ALLOC_RETRY);
526 		VM_OBJECT_UNLOCK(mem->am_obj);
527 		if ((m->flags & PG_ZERO) == 0)
528 			pmap_zero_page(m);
529 		AGP_DPF("found page pa=%#x\n", VM_PAGE_TO_PHYS(m));
530 
531 		/*
532 		 * Install entries in the GATT, making sure that if
533 		 * AGP_PAGE_SIZE < PAGE_SIZE and mem->am_size is not
534 		 * aligned to PAGE_SIZE, we don't modify too many GATT
535 		 * entries.
536 		 */
537 		for (j = 0; j < PAGE_SIZE && i + j < mem->am_size;
538 		     j += AGP_PAGE_SIZE) {
539 			vm_offset_t pa = VM_PAGE_TO_PHYS(m) + j;
540 			AGP_DPF("binding offset %#x to pa %#x\n",
541 				offset + i + j, pa);
542 			error = AGP_BIND_PAGE(dev, offset + i + j, pa);
543 			if (error) {
544 				/*
545 				 * Bail out. Reverse all the mappings
546 				 * and unwire the pages.
547 				 */
548 				vm_page_lock_queues();
549 				vm_page_wakeup(m);
550 				vm_page_unlock_queues();
551 				for (k = 0; k < i + j; k += AGP_PAGE_SIZE)
552 					AGP_UNBIND_PAGE(dev, offset + k);
553 				VM_OBJECT_LOCK(mem->am_obj);
554 				for (k = 0; k <= i; k += PAGE_SIZE) {
555 					m = vm_page_lookup(mem->am_obj,
556 							   OFF_TO_IDX(k));
557 					vm_page_lock_queues();
558 					vm_page_unwire(m, 0);
559 					vm_page_unlock_queues();
560 				}
561 				VM_OBJECT_UNLOCK(mem->am_obj);
562 				lockmgr(&sc->as_lock, LK_RELEASE, 0, curthread);
563 				return error;
564 			}
565 		}
566 		vm_page_lock_queues();
567 		vm_page_wakeup(m);
568 		vm_page_unlock_queues();
569 	}
570 
571 	/*
572 	 * Flush the cpu cache since we are providing a new mapping
573 	 * for these pages.
574 	 */
575 	agp_flush_cache();
576 
577 	/*
578 	 * Make sure the chipset gets the new mappings.
579 	 */
580 	AGP_FLUSH_TLB(dev);
581 
582 	mem->am_offset = offset;
583 	mem->am_is_bound = 1;
584 
585 	lockmgr(&sc->as_lock, LK_RELEASE, 0, curthread);
586 
587 	return 0;
588 }
589 
590 int
591 agp_generic_unbind_memory(device_t dev, struct agp_memory *mem)
592 {
593 	struct agp_softc *sc = device_get_softc(dev);
594 	vm_page_t m;
595 	int i;
596 
597 	lockmgr(&sc->as_lock, LK_EXCLUSIVE, 0, curthread);
598 
599 	if (!mem->am_is_bound) {
600 		device_printf(dev, "memory is not bound\n");
601 		return EINVAL;
602 	}
603 
604 
605 	/*
606 	 * Unbind the individual pages and flush the chipset's
607 	 * TLB. Unwire the pages so they can be swapped.
608 	 */
609 	for (i = 0; i < mem->am_size; i += AGP_PAGE_SIZE)
610 		AGP_UNBIND_PAGE(dev, mem->am_offset + i);
611 	VM_OBJECT_LOCK(mem->am_obj);
612 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
613 		m = vm_page_lookup(mem->am_obj, atop(i));
614 		vm_page_lock_queues();
615 		vm_page_unwire(m, 0);
616 		vm_page_unlock_queues();
617 	}
618 	VM_OBJECT_UNLOCK(mem->am_obj);
619 
620 	agp_flush_cache();
621 	AGP_FLUSH_TLB(dev);
622 
623 	mem->am_offset = 0;
624 	mem->am_is_bound = 0;
625 
626 	lockmgr(&sc->as_lock, LK_RELEASE, 0, curthread);
627 
628 	return 0;
629 }
630 
631 /* Helper functions for implementing user/kernel api */
632 
633 static int
634 agp_acquire_helper(device_t dev, enum agp_acquire_state state)
635 {
636 	struct agp_softc *sc = device_get_softc(dev);
637 
638 	if (sc->as_state != AGP_ACQUIRE_FREE)
639 		return EBUSY;
640 	sc->as_state = state;
641 
642 	return 0;
643 }
644 
645 static int
646 agp_release_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 0;
652 
653 	if (sc->as_state != state)
654 		return EBUSY;
655 
656 	sc->as_state = AGP_ACQUIRE_FREE;
657 	return 0;
658 }
659 
660 static struct agp_memory *
661 agp_find_memory(device_t dev, int id)
662 {
663 	struct agp_softc *sc = device_get_softc(dev);
664 	struct agp_memory *mem;
665 
666 	AGP_DPF("searching for memory block %d\n", id);
667 	TAILQ_FOREACH(mem, &sc->as_memory, am_link) {
668 		AGP_DPF("considering memory block %d\n", mem->am_id);
669 		if (mem->am_id == id)
670 			return mem;
671 	}
672 	return 0;
673 }
674 
675 /* Implementation of the userland ioctl api */
676 
677 static int
678 agp_info_user(device_t dev, agp_info *info)
679 {
680 	struct agp_softc *sc = device_get_softc(dev);
681 
682 	bzero(info, sizeof *info);
683 	info->bridge_id = pci_get_devid(dev);
684 	info->agp_mode =
685 	    pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
686 	info->aper_base = rman_get_start(sc->as_aperture);
687 	info->aper_size = AGP_GET_APERTURE(dev) >> 20;
688 	info->pg_total = info->pg_system = sc->as_maxmem >> AGP_PAGE_SHIFT;
689 	info->pg_used = sc->as_allocated >> AGP_PAGE_SHIFT;
690 
691 	return 0;
692 }
693 
694 static int
695 agp_setup_user(device_t dev, agp_setup *setup)
696 {
697 	return AGP_ENABLE(dev, setup->agp_mode);
698 }
699 
700 static int
701 agp_allocate_user(device_t dev, agp_allocate *alloc)
702 {
703 	struct agp_memory *mem;
704 
705 	mem = AGP_ALLOC_MEMORY(dev,
706 			       alloc->type,
707 			       alloc->pg_count << AGP_PAGE_SHIFT);
708 	if (mem) {
709 		alloc->key = mem->am_id;
710 		alloc->physical = mem->am_physical;
711 		return 0;
712 	} else {
713 		return ENOMEM;
714 	}
715 }
716 
717 static int
718 agp_deallocate_user(device_t dev, int id)
719 {
720 	struct agp_memory *mem = agp_find_memory(dev, id);;
721 
722 	if (mem) {
723 		AGP_FREE_MEMORY(dev, mem);
724 		return 0;
725 	} else {
726 		return ENOENT;
727 	}
728 }
729 
730 static int
731 agp_bind_user(device_t dev, agp_bind *bind)
732 {
733 	struct agp_memory *mem = agp_find_memory(dev, bind->key);
734 
735 	if (!mem)
736 		return ENOENT;
737 
738 	return AGP_BIND_MEMORY(dev, mem, bind->pg_start << AGP_PAGE_SHIFT);
739 }
740 
741 static int
742 agp_unbind_user(device_t dev, agp_unbind *unbind)
743 {
744 	struct agp_memory *mem = agp_find_memory(dev, unbind->key);
745 
746 	if (!mem)
747 		return ENOENT;
748 
749 	return AGP_UNBIND_MEMORY(dev, mem);
750 }
751 
752 static int
753 agp_open(dev_t kdev, int oflags, int devtype, struct thread *td)
754 {
755 	device_t dev = KDEV2DEV(kdev);
756 	struct agp_softc *sc = device_get_softc(dev);
757 
758 	if (!sc->as_isopen) {
759 		sc->as_isopen = 1;
760 		device_busy(dev);
761 	}
762 
763 	return 0;
764 }
765 
766 static int
767 agp_close(dev_t kdev, int fflag, int devtype, struct thread *td)
768 {
769 	device_t dev = KDEV2DEV(kdev);
770 	struct agp_softc *sc = device_get_softc(dev);
771 	struct agp_memory *mem;
772 
773 	/*
774 	 * Clear the GATT and force release on last close
775 	 */
776 	while ((mem = TAILQ_FIRST(&sc->as_memory)) != 0) {
777 		if (mem->am_is_bound)
778 			AGP_UNBIND_MEMORY(dev, mem);
779 		AGP_FREE_MEMORY(dev, mem);
780 	}
781 	if (sc->as_state == AGP_ACQUIRE_USER)
782 		agp_release_helper(dev, AGP_ACQUIRE_USER);
783 	sc->as_isopen = 0;
784 	device_unbusy(dev);
785 
786 	return 0;
787 }
788 
789 static int
790 agp_ioctl(dev_t kdev, u_long cmd, caddr_t data, int fflag, struct thread *td)
791 {
792 	device_t dev = KDEV2DEV(kdev);
793 
794 	switch (cmd) {
795 	case AGPIOC_INFO:
796 		return agp_info_user(dev, (agp_info *) data);
797 
798 	case AGPIOC_ACQUIRE:
799 		return agp_acquire_helper(dev, AGP_ACQUIRE_USER);
800 
801 	case AGPIOC_RELEASE:
802 		return agp_release_helper(dev, AGP_ACQUIRE_USER);
803 
804 	case AGPIOC_SETUP:
805 		return agp_setup_user(dev, (agp_setup *)data);
806 
807 	case AGPIOC_ALLOCATE:
808 		return agp_allocate_user(dev, (agp_allocate *)data);
809 
810 	case AGPIOC_DEALLOCATE:
811 		return agp_deallocate_user(dev, *(int *) data);
812 
813 	case AGPIOC_BIND:
814 		return agp_bind_user(dev, (agp_bind *)data);
815 
816 	case AGPIOC_UNBIND:
817 		return agp_unbind_user(dev, (agp_unbind *)data);
818 
819 	}
820 
821 	return EINVAL;
822 }
823 
824 static int
825 agp_mmap(dev_t kdev, vm_offset_t offset, vm_paddr_t *paddr, int prot)
826 {
827 	device_t dev = KDEV2DEV(kdev);
828 	struct agp_softc *sc = device_get_softc(dev);
829 
830 	if (offset > AGP_GET_APERTURE(dev))
831 		return -1;
832 	*paddr = rman_get_start(sc->as_aperture) + offset;
833 	return 0;
834 }
835 
836 /* Implementation of the kernel api */
837 
838 device_t
839 agp_find_device()
840 {
841 	if (!agp_devclass)
842 		return 0;
843 	return devclass_get_device(agp_devclass, 0);
844 }
845 
846 enum agp_acquire_state
847 agp_state(device_t dev)
848 {
849 	struct agp_softc *sc = device_get_softc(dev);
850 	return sc->as_state;
851 }
852 
853 void
854 agp_get_info(device_t dev, struct agp_info *info)
855 {
856 	struct agp_softc *sc = device_get_softc(dev);
857 
858 	info->ai_mode =
859 		pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
860 	info->ai_aperture_base = rman_get_start(sc->as_aperture);
861 	info->ai_aperture_size = rman_get_size(sc->as_aperture);
862 	info->ai_aperture_va = (vm_offset_t) rman_get_virtual(sc->as_aperture);
863 	info->ai_memory_allowed = sc->as_maxmem;
864 	info->ai_memory_used = sc->as_allocated;
865 }
866 
867 int
868 agp_acquire(device_t dev)
869 {
870 	return agp_acquire_helper(dev, AGP_ACQUIRE_KERNEL);
871 }
872 
873 int
874 agp_release(device_t dev)
875 {
876 	return agp_release_helper(dev, AGP_ACQUIRE_KERNEL);
877 }
878 
879 int
880 agp_enable(device_t dev, u_int32_t mode)
881 {
882 	return AGP_ENABLE(dev, mode);
883 }
884 
885 void *agp_alloc_memory(device_t dev, int type, vm_size_t bytes)
886 {
887 	return  (void *) AGP_ALLOC_MEMORY(dev, type, bytes);
888 }
889 
890 void agp_free_memory(device_t dev, void *handle)
891 {
892 	struct agp_memory *mem = (struct agp_memory *) handle;
893 	AGP_FREE_MEMORY(dev, mem);
894 }
895 
896 int agp_bind_memory(device_t dev, void *handle, vm_offset_t offset)
897 {
898 	struct agp_memory *mem = (struct agp_memory *) handle;
899 	return AGP_BIND_MEMORY(dev, mem, offset);
900 }
901 
902 int agp_unbind_memory(device_t dev, void *handle)
903 {
904 	struct agp_memory *mem = (struct agp_memory *) handle;
905 	return AGP_UNBIND_MEMORY(dev, mem);
906 }
907 
908 void agp_memory_info(device_t dev, void *handle, struct
909 		     agp_memory_info *mi)
910 {
911 	struct agp_memory *mem = (struct agp_memory *) handle;
912 
913 	mi->ami_size = mem->am_size;
914 	mi->ami_physical = mem->am_physical;
915 	mi->ami_offset = mem->am_offset;
916 	mi->ami_is_bound = mem->am_is_bound;
917 }
918