xref: /freebsd/sys/dev/agp/agp.c (revision 1669d8afc64812c8d2d1d147ae1fd42ff441e1b1)
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/agp/agppriv.h>
46 #include <dev/agp/agpvar.h>
47 #include <dev/agp/agpreg.h>
48 #include <dev/pci/pcivar.h>
49 #include <dev/pci/pcireg.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 #if defined(__i386__) || defined(__amd64__)
91 	wbinvd();
92 #endif
93 }
94 
95 u_int8_t
96 agp_find_caps(device_t dev)
97 {
98 	int capreg;
99 
100 
101 	if (pci_find_extcap(dev, PCIY_AGP, &capreg) != 0)
102 		capreg = 0;
103 	return (capreg);
104 }
105 
106 /*
107  * Find an AGP display device (if any).
108  */
109 static device_t
110 agp_find_display(void)
111 {
112 	devclass_t pci = devclass_find("pci");
113 	device_t bus, dev = 0;
114 	device_t *kids;
115 	int busnum, numkids, i;
116 
117 	for (busnum = 0; busnum < devclass_get_maxunit(pci); busnum++) {
118 		bus = devclass_get_device(pci, busnum);
119 		if (!bus)
120 			continue;
121 		device_get_children(bus, &kids, &numkids);
122 		for (i = 0; i < numkids; i++) {
123 			dev = kids[i];
124 			if (pci_get_class(dev) == PCIC_DISPLAY
125 			    && pci_get_subclass(dev) == PCIS_DISPLAY_VGA)
126 				if (agp_find_caps(dev)) {
127 					free(kids, M_TEMP);
128 					return dev;
129 				}
130 
131 		}
132 		free(kids, M_TEMP);
133 	}
134 
135 	return 0;
136 }
137 
138 struct agp_gatt *
139 agp_alloc_gatt(device_t dev)
140 {
141 	u_int32_t apsize = AGP_GET_APERTURE(dev);
142 	u_int32_t entries = apsize >> AGP_PAGE_SHIFT;
143 	struct agp_gatt *gatt;
144 
145 	if (bootverbose)
146 		device_printf(dev,
147 			      "allocating GATT for aperture of size %dM\n",
148 			      apsize / (1024*1024));
149 
150 	if (entries == 0) {
151 		device_printf(dev, "bad aperture size\n");
152 		return NULL;
153 	}
154 
155 	gatt = malloc(sizeof(struct agp_gatt), M_AGP, M_NOWAIT);
156 	if (!gatt)
157 		return 0;
158 
159 	gatt->ag_entries = entries;
160 	gatt->ag_virtual = contigmalloc(entries * sizeof(u_int32_t), M_AGP, 0,
161 					0, ~0, PAGE_SIZE, 0);
162 	if (!gatt->ag_virtual) {
163 		if (bootverbose)
164 			device_printf(dev, "contiguous allocation failed\n");
165 		free(gatt, M_AGP);
166 		return 0;
167 	}
168 	bzero(gatt->ag_virtual, entries * sizeof(u_int32_t));
169 	gatt->ag_physical = vtophys((vm_offset_t) gatt->ag_virtual);
170 	agp_flush_cache();
171 
172 	return gatt;
173 }
174 
175 void
176 agp_free_gatt(struct agp_gatt *gatt)
177 {
178 	contigfree(gatt->ag_virtual,
179 		   gatt->ag_entries * sizeof(u_int32_t), M_AGP);
180 	free(gatt, M_AGP);
181 }
182 
183 static u_int agp_max[][2] = {
184 	{0,	0},
185 	{32,	4},
186 	{64,	28},
187 	{128,	96},
188 	{256,	204},
189 	{512,	440},
190 	{1024,	942},
191 	{2048,	1920},
192 	{4096,	3932}
193 };
194 #define agp_max_size	(sizeof(agp_max) / sizeof(agp_max[0]))
195 
196 /**
197  * Sets the PCI resource which represents the AGP aperture.
198  *
199  * If not called, the default AGP aperture resource of AGP_APBASE will
200  * be used.  Must be called before agp_generic_attach().
201  */
202 void
203 agp_set_aperture_resource(device_t dev, int rid)
204 {
205 	struct agp_softc *sc = device_get_softc(dev);
206 
207 	sc->as_aperture_rid = rid;
208 }
209 
210 int
211 agp_generic_attach(device_t dev)
212 {
213 	struct agp_softc *sc = device_get_softc(dev);
214 	int i;
215 	u_int memsize;
216 
217 	/*
218 	 * Find and map the aperture, RF_SHAREABLE for DRM but not RF_ACTIVE
219 	 * because the kernel doesn't need to map it.
220 	 */
221 	if (sc->as_aperture_rid == 0)
222 		sc->as_aperture_rid = AGP_APBASE;
223 
224 	sc->as_aperture = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
225 	    &sc->as_aperture_rid, RF_SHAREABLE);
226 	if (!sc->as_aperture)
227 		return ENOMEM;
228 
229 	/*
230 	 * Work out an upper bound for agp memory allocation. This
231 	 * uses a heurisitc table from the Linux driver.
232 	 */
233 	memsize = ptoa(Maxmem) >> 20;
234 	for (i = 0; i < agp_max_size; i++) {
235 		if (memsize <= agp_max[i][0])
236 			break;
237 	}
238 	if (i == agp_max_size) i = agp_max_size - 1;
239 	sc->as_maxmem = agp_max[i][1] << 20U;
240 
241 	/*
242 	 * The lock is used to prevent re-entry to
243 	 * agp_generic_bind_memory() since that function can sleep.
244 	 */
245 	mtx_init(&sc->as_lock, "agp lock", NULL, MTX_DEF);
246 
247 	/*
248 	 * Initialise stuff for the userland device.
249 	 */
250 	agp_devclass = devclass_find("agp");
251 	TAILQ_INIT(&sc->as_memory);
252 	sc->as_nextid = 1;
253 
254 	sc->as_devnode = make_dev(&agp_cdevsw,
255 				  device_get_unit(dev),
256 				  UID_ROOT,
257 				  GID_WHEEL,
258 				  0600,
259 				  "agpgart");
260 
261 	return 0;
262 }
263 
264 void
265 agp_free_cdev(device_t dev)
266 {
267 	struct agp_softc *sc = device_get_softc(dev);
268 
269 	destroy_dev(sc->as_devnode);
270 }
271 
272 void
273 agp_free_res(device_t dev)
274 {
275 	struct agp_softc *sc = device_get_softc(dev);
276 
277 	bus_release_resource(dev, SYS_RES_MEMORY, sc->as_aperture_rid,
278 	    sc->as_aperture);
279 	mtx_destroy(&sc->as_lock);
280 	agp_flush_cache();
281 }
282 
283 int
284 agp_generic_detach(device_t dev)
285 {
286 
287 	agp_free_cdev(dev);
288 	agp_free_res(dev);
289 	return 0;
290 }
291 
292 /**
293  * Default AGP aperture size detection which simply returns the size of
294  * the aperture's PCI resource.
295  */
296 int
297 agp_generic_get_aperture(device_t dev)
298 {
299 	struct agp_softc *sc = device_get_softc(dev);
300 
301 	return rman_get_size(sc->as_aperture);
302 }
303 
304 /**
305  * Default AGP aperture size setting function, which simply doesn't allow
306  * changes to resource size.
307  */
308 int
309 agp_generic_set_aperture(device_t dev, u_int32_t aperture)
310 {
311 	u_int32_t current_aperture;
312 
313 	current_aperture = AGP_GET_APERTURE(dev);
314 	if (current_aperture != aperture)
315 		return EINVAL;
316 	else
317 		return 0;
318 }
319 
320 /*
321  * This does the enable logic for v3, with the same topology
322  * restrictions as in place for v2 -- one bus, one device on the bus.
323  */
324 static int
325 agp_v3_enable(device_t dev, device_t mdev, u_int32_t mode)
326 {
327 	u_int32_t tstatus, mstatus;
328 	u_int32_t command;
329 	int rq, sba, fw, rate, arqsz, cal;
330 
331 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
332 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
333 
334 	/* Set RQ to the min of mode, tstatus and mstatus */
335 	rq = AGP_MODE_GET_RQ(mode);
336 	if (AGP_MODE_GET_RQ(tstatus) < rq)
337 		rq = AGP_MODE_GET_RQ(tstatus);
338 	if (AGP_MODE_GET_RQ(mstatus) < rq)
339 		rq = AGP_MODE_GET_RQ(mstatus);
340 
341 	/*
342 	 * ARQSZ - Set the value to the maximum one.
343 	 * Don't allow the mode register to override values.
344 	 */
345 	arqsz = AGP_MODE_GET_ARQSZ(mode);
346 	if (AGP_MODE_GET_ARQSZ(tstatus) > rq)
347 		rq = AGP_MODE_GET_ARQSZ(tstatus);
348 	if (AGP_MODE_GET_ARQSZ(mstatus) > rq)
349 		rq = AGP_MODE_GET_ARQSZ(mstatus);
350 
351 	/* Calibration cycle - don't allow override by mode register */
352 	cal = AGP_MODE_GET_CAL(tstatus);
353 	if (AGP_MODE_GET_CAL(mstatus) < cal)
354 		cal = AGP_MODE_GET_CAL(mstatus);
355 
356 	/* SBA must be supported for AGP v3. */
357 	sba = 1;
358 
359 	/* Set FW if all three support it. */
360 	fw = (AGP_MODE_GET_FW(tstatus)
361 	       & AGP_MODE_GET_FW(mstatus)
362 	       & AGP_MODE_GET_FW(mode));
363 
364 	/* Figure out the max rate */
365 	rate = (AGP_MODE_GET_RATE(tstatus)
366 		& AGP_MODE_GET_RATE(mstatus)
367 		& AGP_MODE_GET_RATE(mode));
368 	if (rate & AGP_MODE_V3_RATE_8x)
369 		rate = AGP_MODE_V3_RATE_8x;
370 	else
371 		rate = AGP_MODE_V3_RATE_4x;
372 	if (bootverbose)
373 		device_printf(dev, "Setting AGP v3 mode %d\n", rate * 4);
374 
375 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, 0, 4);
376 
377 	/* Construct the new mode word and tell the hardware */
378 	command = 0;
379 	command = AGP_MODE_SET_RQ(0, rq);
380 	command = AGP_MODE_SET_ARQSZ(command, arqsz);
381 	command = AGP_MODE_SET_CAL(command, cal);
382 	command = AGP_MODE_SET_SBA(command, sba);
383 	command = AGP_MODE_SET_FW(command, fw);
384 	command = AGP_MODE_SET_RATE(command, rate);
385 	command = AGP_MODE_SET_MODE_3(command, 1);
386 	command = AGP_MODE_SET_AGP(command, 1);
387 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
388 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
389 
390 	return 0;
391 }
392 
393 static int
394 agp_v2_enable(device_t dev, device_t mdev, u_int32_t mode)
395 {
396 	u_int32_t tstatus, mstatus;
397 	u_int32_t command;
398 	int rq, sba, fw, rate;
399 
400 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
401 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
402 
403 	/* Set RQ to the min of mode, tstatus and mstatus */
404 	rq = AGP_MODE_GET_RQ(mode);
405 	if (AGP_MODE_GET_RQ(tstatus) < rq)
406 		rq = AGP_MODE_GET_RQ(tstatus);
407 	if (AGP_MODE_GET_RQ(mstatus) < rq)
408 		rq = AGP_MODE_GET_RQ(mstatus);
409 
410 	/* Set SBA if all three can deal with SBA */
411 	sba = (AGP_MODE_GET_SBA(tstatus)
412 	       & AGP_MODE_GET_SBA(mstatus)
413 	       & AGP_MODE_GET_SBA(mode));
414 
415 	/* Similar for FW */
416 	fw = (AGP_MODE_GET_FW(tstatus)
417 	       & AGP_MODE_GET_FW(mstatus)
418 	       & AGP_MODE_GET_FW(mode));
419 
420 	/* Figure out the max rate */
421 	rate = (AGP_MODE_GET_RATE(tstatus)
422 		& AGP_MODE_GET_RATE(mstatus)
423 		& AGP_MODE_GET_RATE(mode));
424 	if (rate & AGP_MODE_V2_RATE_4x)
425 		rate = AGP_MODE_V2_RATE_4x;
426 	else if (rate & AGP_MODE_V2_RATE_2x)
427 		rate = AGP_MODE_V2_RATE_2x;
428 	else
429 		rate = AGP_MODE_V2_RATE_1x;
430 	if (bootverbose)
431 		device_printf(dev, "Setting AGP v2 mode %d\n", rate);
432 
433 	/* Construct the new mode word and tell the hardware */
434 	command = 0;
435 	command = AGP_MODE_SET_RQ(0, rq);
436 	command = AGP_MODE_SET_SBA(command, sba);
437 	command = AGP_MODE_SET_FW(command, fw);
438 	command = AGP_MODE_SET_RATE(command, rate);
439 	command = AGP_MODE_SET_AGP(command, 1);
440 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
441 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
442 
443 	return 0;
444 }
445 
446 int
447 agp_generic_enable(device_t dev, u_int32_t mode)
448 {
449 	device_t mdev = agp_find_display();
450 	u_int32_t tstatus, mstatus;
451 
452 	if (!mdev) {
453 		AGP_DPF("can't find display\n");
454 		return ENXIO;
455 	}
456 
457 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
458 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
459 
460 	/*
461 	 * Check display and bridge for AGP v3 support.  AGP v3 allows
462 	 * more variety in topology than v2, e.g. multiple AGP devices
463 	 * attached to one bridge, or multiple AGP bridges in one
464 	 * system.  This doesn't attempt to address those situations,
465 	 * but should work fine for a classic single AGP slot system
466 	 * with AGP v3.
467 	 */
468 	if (AGP_MODE_GET_MODE_3(mode) &&
469 	    AGP_MODE_GET_MODE_3(tstatus) &&
470 	    AGP_MODE_GET_MODE_3(mstatus))
471 		return (agp_v3_enable(dev, mdev, mode));
472 	else
473 		return (agp_v2_enable(dev, mdev, mode));
474 }
475 
476 struct agp_memory *
477 agp_generic_alloc_memory(device_t dev, int type, vm_size_t size)
478 {
479 	struct agp_softc *sc = device_get_softc(dev);
480 	struct agp_memory *mem;
481 
482 	if ((size & (AGP_PAGE_SIZE - 1)) != 0)
483 		return 0;
484 
485 	if (sc->as_allocated + size > sc->as_maxmem)
486 		return 0;
487 
488 	if (type != 0) {
489 		printf("agp_generic_alloc_memory: unsupported type %d\n",
490 		       type);
491 		return 0;
492 	}
493 
494 	mem = malloc(sizeof *mem, M_AGP, M_WAITOK);
495 	mem->am_id = sc->as_nextid++;
496 	mem->am_size = size;
497 	mem->am_type = 0;
498 	mem->am_obj = vm_object_allocate(OBJT_DEFAULT, atop(round_page(size)));
499 	mem->am_physical = 0;
500 	mem->am_offset = 0;
501 	mem->am_is_bound = 0;
502 	TAILQ_INSERT_TAIL(&sc->as_memory, mem, am_link);
503 	sc->as_allocated += size;
504 
505 	return mem;
506 }
507 
508 int
509 agp_generic_free_memory(device_t dev, struct agp_memory *mem)
510 {
511 	struct agp_softc *sc = device_get_softc(dev);
512 
513 	if (mem->am_is_bound)
514 		return EBUSY;
515 
516 	sc->as_allocated -= mem->am_size;
517 	TAILQ_REMOVE(&sc->as_memory, mem, am_link);
518 	vm_object_deallocate(mem->am_obj);
519 	free(mem, M_AGP);
520 	return 0;
521 }
522 
523 int
524 agp_generic_bind_memory(device_t dev, struct agp_memory *mem,
525 			vm_offset_t offset)
526 {
527 	struct agp_softc *sc = device_get_softc(dev);
528 	vm_offset_t i, j, k;
529 	vm_page_t m;
530 	int error;
531 
532 	/* Do some sanity checks first. */
533 	if (offset < 0 || (offset & (AGP_PAGE_SIZE - 1)) != 0 ||
534 	    offset + mem->am_size > AGP_GET_APERTURE(dev)) {
535 		device_printf(dev, "binding memory at bad offset %#x\n",
536 		    (int)offset);
537 		return EINVAL;
538 	}
539 
540 	/*
541 	 * Allocate the pages early, before acquiring the lock,
542 	 * because vm_page_grab() used with VM_ALLOC_RETRY may
543 	 * block and we can't hold a mutex while blocking.
544 	 */
545 	VM_OBJECT_LOCK(mem->am_obj);
546 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
547 		/*
548 		 * Find a page from the object and wire it
549 		 * down. This page will be mapped using one or more
550 		 * entries in the GATT (assuming that PAGE_SIZE >=
551 		 * AGP_PAGE_SIZE. If this is the first call to bind,
552 		 * the pages will be allocated and zeroed.
553 		 */
554 		m = vm_page_grab(mem->am_obj, OFF_TO_IDX(i),
555 		    VM_ALLOC_WIRED | VM_ALLOC_ZERO | VM_ALLOC_RETRY);
556 		AGP_DPF("found page pa=%#x\n", VM_PAGE_TO_PHYS(m));
557 	}
558 	VM_OBJECT_UNLOCK(mem->am_obj);
559 
560 	mtx_lock(&sc->as_lock);
561 
562 	if (mem->am_is_bound) {
563 		device_printf(dev, "memory already bound\n");
564 		error = EINVAL;
565 		VM_OBJECT_LOCK(mem->am_obj);
566 		goto bad;
567 	}
568 
569 	/*
570 	 * Bind the individual pages and flush the chipset's
571 	 * TLB.
572 	 */
573 	VM_OBJECT_LOCK(mem->am_obj);
574 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
575 		m = vm_page_lookup(mem->am_obj, OFF_TO_IDX(i));
576 
577 		/*
578 		 * Install entries in the GATT, making sure that if
579 		 * AGP_PAGE_SIZE < PAGE_SIZE and mem->am_size is not
580 		 * aligned to PAGE_SIZE, we don't modify too many GATT
581 		 * entries.
582 		 */
583 		for (j = 0; j < PAGE_SIZE && i + j < mem->am_size;
584 		     j += AGP_PAGE_SIZE) {
585 			vm_offset_t pa = VM_PAGE_TO_PHYS(m) + j;
586 			AGP_DPF("binding offset %#x to pa %#x\n",
587 				offset + i + j, pa);
588 			error = AGP_BIND_PAGE(dev, offset + i + j, pa);
589 			if (error) {
590 				/*
591 				 * Bail out. Reverse all the mappings
592 				 * and unwire the pages.
593 				 */
594 				vm_page_wakeup(m);
595 				for (k = 0; k < i + j; k += AGP_PAGE_SIZE)
596 					AGP_UNBIND_PAGE(dev, offset + k);
597 				goto bad;
598 			}
599 		}
600 		vm_page_wakeup(m);
601 	}
602 	VM_OBJECT_UNLOCK(mem->am_obj);
603 
604 	/*
605 	 * Flush the cpu cache since we are providing a new mapping
606 	 * for these pages.
607 	 */
608 	agp_flush_cache();
609 
610 	/*
611 	 * Make sure the chipset gets the new mappings.
612 	 */
613 	AGP_FLUSH_TLB(dev);
614 
615 	mem->am_offset = offset;
616 	mem->am_is_bound = 1;
617 
618 	mtx_unlock(&sc->as_lock);
619 
620 	return 0;
621 bad:
622 	mtx_unlock(&sc->as_lock);
623 	VM_OBJECT_LOCK_ASSERT(mem->am_obj, MA_OWNED);
624 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
625 		m = vm_page_lookup(mem->am_obj, OFF_TO_IDX(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 	return error;
633 }
634 
635 int
636 agp_generic_unbind_memory(device_t dev, struct agp_memory *mem)
637 {
638 	struct agp_softc *sc = device_get_softc(dev);
639 	vm_page_t m;
640 	int i;
641 
642 	mtx_lock(&sc->as_lock);
643 
644 	if (!mem->am_is_bound) {
645 		device_printf(dev, "memory is not bound\n");
646 		mtx_unlock(&sc->as_lock);
647 		return EINVAL;
648 	}
649 
650 
651 	/*
652 	 * Unbind the individual pages and flush the chipset's
653 	 * TLB. Unwire the pages so they can be swapped.
654 	 */
655 	for (i = 0; i < mem->am_size; i += AGP_PAGE_SIZE)
656 		AGP_UNBIND_PAGE(dev, mem->am_offset + i);
657 	VM_OBJECT_LOCK(mem->am_obj);
658 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
659 		m = vm_page_lookup(mem->am_obj, atop(i));
660 		vm_page_lock_queues();
661 		vm_page_unwire(m, 0);
662 		vm_page_unlock_queues();
663 	}
664 	VM_OBJECT_UNLOCK(mem->am_obj);
665 
666 	agp_flush_cache();
667 	AGP_FLUSH_TLB(dev);
668 
669 	mem->am_offset = 0;
670 	mem->am_is_bound = 0;
671 
672 	mtx_unlock(&sc->as_lock);
673 
674 	return 0;
675 }
676 
677 /* Helper functions for implementing user/kernel api */
678 
679 static int
680 agp_acquire_helper(device_t dev, enum agp_acquire_state state)
681 {
682 	struct agp_softc *sc = device_get_softc(dev);
683 
684 	if (sc->as_state != AGP_ACQUIRE_FREE)
685 		return EBUSY;
686 	sc->as_state = state;
687 
688 	return 0;
689 }
690 
691 static int
692 agp_release_helper(device_t dev, enum agp_acquire_state state)
693 {
694 	struct agp_softc *sc = device_get_softc(dev);
695 
696 	if (sc->as_state == AGP_ACQUIRE_FREE)
697 		return 0;
698 
699 	if (sc->as_state != state)
700 		return EBUSY;
701 
702 	sc->as_state = AGP_ACQUIRE_FREE;
703 	return 0;
704 }
705 
706 static struct agp_memory *
707 agp_find_memory(device_t dev, int id)
708 {
709 	struct agp_softc *sc = device_get_softc(dev);
710 	struct agp_memory *mem;
711 
712 	AGP_DPF("searching for memory block %d\n", id);
713 	TAILQ_FOREACH(mem, &sc->as_memory, am_link) {
714 		AGP_DPF("considering memory block %d\n", mem->am_id);
715 		if (mem->am_id == id)
716 			return mem;
717 	}
718 	return 0;
719 }
720 
721 /* Implementation of the userland ioctl api */
722 
723 static int
724 agp_info_user(device_t dev, agp_info *info)
725 {
726 	struct agp_softc *sc = device_get_softc(dev);
727 
728 	bzero(info, sizeof *info);
729 	info->bridge_id = pci_get_devid(dev);
730 	info->agp_mode =
731 	    pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
732 	info->aper_base = rman_get_start(sc->as_aperture);
733 	info->aper_size = AGP_GET_APERTURE(dev) >> 20;
734 	info->pg_total = info->pg_system = sc->as_maxmem >> AGP_PAGE_SHIFT;
735 	info->pg_used = sc->as_allocated >> AGP_PAGE_SHIFT;
736 
737 	return 0;
738 }
739 
740 static int
741 agp_setup_user(device_t dev, agp_setup *setup)
742 {
743 	return AGP_ENABLE(dev, setup->agp_mode);
744 }
745 
746 static int
747 agp_allocate_user(device_t dev, agp_allocate *alloc)
748 {
749 	struct agp_memory *mem;
750 
751 	mem = AGP_ALLOC_MEMORY(dev,
752 			       alloc->type,
753 			       alloc->pg_count << AGP_PAGE_SHIFT);
754 	if (mem) {
755 		alloc->key = mem->am_id;
756 		alloc->physical = mem->am_physical;
757 		return 0;
758 	} else {
759 		return ENOMEM;
760 	}
761 }
762 
763 static int
764 agp_deallocate_user(device_t dev, int id)
765 {
766 	struct agp_memory *mem = agp_find_memory(dev, id);;
767 
768 	if (mem) {
769 		AGP_FREE_MEMORY(dev, mem);
770 		return 0;
771 	} else {
772 		return ENOENT;
773 	}
774 }
775 
776 static int
777 agp_bind_user(device_t dev, agp_bind *bind)
778 {
779 	struct agp_memory *mem = agp_find_memory(dev, bind->key);
780 
781 	if (!mem)
782 		return ENOENT;
783 
784 	return AGP_BIND_MEMORY(dev, mem, bind->pg_start << AGP_PAGE_SHIFT);
785 }
786 
787 static int
788 agp_unbind_user(device_t dev, agp_unbind *unbind)
789 {
790 	struct agp_memory *mem = agp_find_memory(dev, unbind->key);
791 
792 	if (!mem)
793 		return ENOENT;
794 
795 	return AGP_UNBIND_MEMORY(dev, mem);
796 }
797 
798 static int
799 agp_open(struct cdev *kdev, int oflags, int devtype, struct thread *td)
800 {
801 	device_t dev = KDEV2DEV(kdev);
802 	struct agp_softc *sc = device_get_softc(dev);
803 
804 	if (!sc->as_isopen) {
805 		sc->as_isopen = 1;
806 		device_busy(dev);
807 	}
808 
809 	return 0;
810 }
811 
812 static int
813 agp_close(struct cdev *kdev, int fflag, int devtype, struct thread *td)
814 {
815 	device_t dev = KDEV2DEV(kdev);
816 	struct agp_softc *sc = device_get_softc(dev);
817 	struct agp_memory *mem;
818 
819 	/*
820 	 * Clear the GATT and force release on last close
821 	 */
822 	while ((mem = TAILQ_FIRST(&sc->as_memory)) != 0) {
823 		if (mem->am_is_bound)
824 			AGP_UNBIND_MEMORY(dev, mem);
825 		AGP_FREE_MEMORY(dev, mem);
826 	}
827 	if (sc->as_state == AGP_ACQUIRE_USER)
828 		agp_release_helper(dev, AGP_ACQUIRE_USER);
829 	sc->as_isopen = 0;
830 	device_unbusy(dev);
831 
832 	return 0;
833 }
834 
835 static int
836 agp_ioctl(struct cdev *kdev, u_long cmd, caddr_t data, int fflag, struct thread *td)
837 {
838 	device_t dev = KDEV2DEV(kdev);
839 
840 	switch (cmd) {
841 	case AGPIOC_INFO:
842 		return agp_info_user(dev, (agp_info *) data);
843 
844 	case AGPIOC_ACQUIRE:
845 		return agp_acquire_helper(dev, AGP_ACQUIRE_USER);
846 
847 	case AGPIOC_RELEASE:
848 		return agp_release_helper(dev, AGP_ACQUIRE_USER);
849 
850 	case AGPIOC_SETUP:
851 		return agp_setup_user(dev, (agp_setup *)data);
852 
853 	case AGPIOC_ALLOCATE:
854 		return agp_allocate_user(dev, (agp_allocate *)data);
855 
856 	case AGPIOC_DEALLOCATE:
857 		return agp_deallocate_user(dev, *(int *) data);
858 
859 	case AGPIOC_BIND:
860 		return agp_bind_user(dev, (agp_bind *)data);
861 
862 	case AGPIOC_UNBIND:
863 		return agp_unbind_user(dev, (agp_unbind *)data);
864 
865 	}
866 
867 	return EINVAL;
868 }
869 
870 static int
871 agp_mmap(struct cdev *kdev, vm_offset_t offset, vm_paddr_t *paddr, int prot)
872 {
873 	device_t dev = KDEV2DEV(kdev);
874 	struct agp_softc *sc = device_get_softc(dev);
875 
876 	if (offset > AGP_GET_APERTURE(dev))
877 		return -1;
878 	*paddr = rman_get_start(sc->as_aperture) + offset;
879 	return 0;
880 }
881 
882 /* Implementation of the kernel api */
883 
884 device_t
885 agp_find_device()
886 {
887 	device_t *children, child;
888 	int i, count;
889 
890 	if (!agp_devclass)
891 		return NULL;
892 	if (devclass_get_devices(agp_devclass, &children, &count) != 0)
893 		return NULL;
894 	child = NULL;
895 	for (i = 0; i < count; i++) {
896 		if (device_is_attached(children[i])) {
897 			child = children[i];
898 			break;
899 		}
900 	}
901 	free(children, M_TEMP);
902 	return child;
903 }
904 
905 enum agp_acquire_state
906 agp_state(device_t dev)
907 {
908 	struct agp_softc *sc = device_get_softc(dev);
909 	return sc->as_state;
910 }
911 
912 void
913 agp_get_info(device_t dev, struct agp_info *info)
914 {
915 	struct agp_softc *sc = device_get_softc(dev);
916 
917 	info->ai_mode =
918 		pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
919 	info->ai_aperture_base = rman_get_start(sc->as_aperture);
920 	info->ai_aperture_size = rman_get_size(sc->as_aperture);
921 	info->ai_memory_allowed = sc->as_maxmem;
922 	info->ai_memory_used = sc->as_allocated;
923 }
924 
925 int
926 agp_acquire(device_t dev)
927 {
928 	return agp_acquire_helper(dev, AGP_ACQUIRE_KERNEL);
929 }
930 
931 int
932 agp_release(device_t dev)
933 {
934 	return agp_release_helper(dev, AGP_ACQUIRE_KERNEL);
935 }
936 
937 int
938 agp_enable(device_t dev, u_int32_t mode)
939 {
940 	return AGP_ENABLE(dev, mode);
941 }
942 
943 void *agp_alloc_memory(device_t dev, int type, vm_size_t bytes)
944 {
945 	return  (void *) AGP_ALLOC_MEMORY(dev, type, bytes);
946 }
947 
948 void agp_free_memory(device_t dev, void *handle)
949 {
950 	struct agp_memory *mem = (struct agp_memory *) handle;
951 	AGP_FREE_MEMORY(dev, mem);
952 }
953 
954 int agp_bind_memory(device_t dev, void *handle, vm_offset_t offset)
955 {
956 	struct agp_memory *mem = (struct agp_memory *) handle;
957 	return AGP_BIND_MEMORY(dev, mem, offset);
958 }
959 
960 int agp_unbind_memory(device_t dev, void *handle)
961 {
962 	struct agp_memory *mem = (struct agp_memory *) handle;
963 	return AGP_UNBIND_MEMORY(dev, mem);
964 }
965 
966 void agp_memory_info(device_t dev, void *handle, struct
967 		     agp_memory_info *mi)
968 {
969 	struct agp_memory *mem = (struct agp_memory *) handle;
970 
971 	mi->ami_size = mem->am_size;
972 	mi->ami_physical = mem->am_physical;
973 	mi->ami_offset = mem->am_offset;
974 	mi->ami_is_bound = mem->am_is_bound;
975 }
976