xref: /freebsd/sys/dev/agp/agp.c (revision 52baf267be42c3e14a9d843c24c953efae7195bd)
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_agp.h"
31 #include "opt_bus.h"
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/malloc.h>
36 #include <sys/kernel.h>
37 #include <sys/module.h>
38 #include <sys/bus.h>
39 #include <sys/conf.h>
40 #include <sys/ioccom.h>
41 #include <sys/agpio.h>
42 #include <sys/lock.h>
43 #include <sys/mutex.h>
44 #include <sys/proc.h>
45 
46 #include <dev/agp/agppriv.h>
47 #include <dev/agp/agpvar.h>
48 #include <dev/agp/agpreg.h>
49 #include <dev/pci/pcivar.h>
50 #include <dev/pci/pcireg.h>
51 
52 #include <vm/vm.h>
53 #include <vm/vm_object.h>
54 #include <vm/vm_page.h>
55 #include <vm/vm_pageout.h>
56 #include <vm/pmap.h>
57 
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 
84 /* Helper functions for implementing chipset mini drivers. */
85 
86 void
87 agp_flush_cache()
88 {
89 #if defined(__i386__) || defined(__amd64__)
90 	wbinvd();
91 #endif
92 }
93 
94 u_int8_t
95 agp_find_caps(device_t dev)
96 {
97 	int capreg;
98 
99 
100 	if (pci_find_cap(dev, PCIY_AGP, &capreg) != 0)
101 		capreg = 0;
102 	return (capreg);
103 }
104 
105 /*
106  * Find an AGP display device (if any).
107  */
108 static device_t
109 agp_find_display(void)
110 {
111 	devclass_t pci = devclass_find("pci");
112 	device_t bus, dev = 0;
113 	device_t *kids;
114 	int busnum, numkids, i;
115 
116 	for (busnum = 0; busnum < devclass_get_maxunit(pci); busnum++) {
117 		bus = devclass_get_device(pci, busnum);
118 		if (!bus)
119 			continue;
120 		if (device_get_children(bus, &kids, &numkids) != 0)
121 			continue;
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 
222 	if (sc->as_aperture_rid != -1) {
223 		if (sc->as_aperture_rid == 0)
224 			sc->as_aperture_rid = AGP_APBASE;
225 
226 		sc->as_aperture = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
227 		    &sc->as_aperture_rid, RF_SHAREABLE);
228 		if (!sc->as_aperture)
229 			return ENOMEM;
230 	}
231 
232 	/*
233 	 * Work out an upper bound for agp memory allocation. This
234 	 * uses a heurisitc table from the Linux driver.
235 	 */
236 	memsize = ptoa(realmem) >> 20;
237 	for (i = 0; i < agp_max_size; i++) {
238 		if (memsize <= agp_max[i][0])
239 			break;
240 	}
241 	if (i == agp_max_size)
242 		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 	mtx_init(&sc->as_lock, "agp lock", NULL, MTX_DEF);
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 	    0, UID_ROOT, GID_WHEEL, 0600, "agpgart");
260 	sc->as_devnode->si_drv1 = dev;
261 
262 	return 0;
263 }
264 
265 void
266 agp_free_cdev(device_t dev)
267 {
268 	struct agp_softc *sc = device_get_softc(dev);
269 
270 	destroy_dev(sc->as_devnode);
271 }
272 
273 void
274 agp_free_res(device_t dev)
275 {
276 	struct agp_softc *sc = device_get_softc(dev);
277 
278 	if (sc->as_aperture != NULL)
279 		bus_release_resource(dev, SYS_RES_MEMORY, sc->as_aperture_rid,
280 		    sc->as_aperture);
281 	mtx_destroy(&sc->as_lock);
282 	agp_flush_cache();
283 }
284 
285 int
286 agp_generic_detach(device_t dev)
287 {
288 
289 	agp_free_cdev(dev);
290 	agp_free_res(dev);
291 	return 0;
292 }
293 
294 /**
295  * Default AGP aperture size detection which simply returns the size of
296  * the aperture's PCI resource.
297  */
298 u_int32_t
299 agp_generic_get_aperture(device_t dev)
300 {
301 	struct agp_softc *sc = device_get_softc(dev);
302 
303 	return rman_get_size(sc->as_aperture);
304 }
305 
306 /**
307  * Default AGP aperture size setting function, which simply doesn't allow
308  * changes to resource size.
309  */
310 int
311 agp_generic_set_aperture(device_t dev, u_int32_t aperture)
312 {
313 	u_int32_t current_aperture;
314 
315 	current_aperture = AGP_GET_APERTURE(dev);
316 	if (current_aperture != aperture)
317 		return EINVAL;
318 	else
319 		return 0;
320 }
321 
322 /*
323  * This does the enable logic for v3, with the same topology
324  * restrictions as in place for v2 -- one bus, one device on the bus.
325  */
326 static int
327 agp_v3_enable(device_t dev, device_t mdev, u_int32_t mode)
328 {
329 	u_int32_t tstatus, mstatus;
330 	u_int32_t command;
331 	int rq, sba, fw, rate, arqsz, cal;
332 
333 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
334 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
335 
336 	/* Set RQ to the min of mode, tstatus and mstatus */
337 	rq = AGP_MODE_GET_RQ(mode);
338 	if (AGP_MODE_GET_RQ(tstatus) < rq)
339 		rq = AGP_MODE_GET_RQ(tstatus);
340 	if (AGP_MODE_GET_RQ(mstatus) < rq)
341 		rq = AGP_MODE_GET_RQ(mstatus);
342 
343 	/*
344 	 * ARQSZ - Set the value to the maximum one.
345 	 * Don't allow the mode register to override values.
346 	 */
347 	arqsz = AGP_MODE_GET_ARQSZ(mode);
348 	if (AGP_MODE_GET_ARQSZ(tstatus) > rq)
349 		rq = AGP_MODE_GET_ARQSZ(tstatus);
350 	if (AGP_MODE_GET_ARQSZ(mstatus) > rq)
351 		rq = AGP_MODE_GET_ARQSZ(mstatus);
352 
353 	/* Calibration cycle - don't allow override by mode register */
354 	cal = AGP_MODE_GET_CAL(tstatus);
355 	if (AGP_MODE_GET_CAL(mstatus) < cal)
356 		cal = AGP_MODE_GET_CAL(mstatus);
357 
358 	/* SBA must be supported for AGP v3. */
359 	sba = 1;
360 
361 	/* Set FW if all three support it. */
362 	fw = (AGP_MODE_GET_FW(tstatus)
363 	       & AGP_MODE_GET_FW(mstatus)
364 	       & AGP_MODE_GET_FW(mode));
365 
366 	/* Figure out the max rate */
367 	rate = (AGP_MODE_GET_RATE(tstatus)
368 		& AGP_MODE_GET_RATE(mstatus)
369 		& AGP_MODE_GET_RATE(mode));
370 	if (rate & AGP_MODE_V3_RATE_8x)
371 		rate = AGP_MODE_V3_RATE_8x;
372 	else
373 		rate = AGP_MODE_V3_RATE_4x;
374 	if (bootverbose)
375 		device_printf(dev, "Setting AGP v3 mode %d\n", rate * 4);
376 
377 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, 0, 4);
378 
379 	/* Construct the new mode word and tell the hardware */
380 	command = 0;
381 	command = AGP_MODE_SET_RQ(0, rq);
382 	command = AGP_MODE_SET_ARQSZ(command, arqsz);
383 	command = AGP_MODE_SET_CAL(command, cal);
384 	command = AGP_MODE_SET_SBA(command, sba);
385 	command = AGP_MODE_SET_FW(command, fw);
386 	command = AGP_MODE_SET_RATE(command, rate);
387 	command = AGP_MODE_SET_MODE_3(command, 1);
388 	command = AGP_MODE_SET_AGP(command, 1);
389 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
390 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
391 
392 	return 0;
393 }
394 
395 static int
396 agp_v2_enable(device_t dev, device_t mdev, u_int32_t mode)
397 {
398 	u_int32_t tstatus, mstatus;
399 	u_int32_t command;
400 	int rq, sba, fw, rate;
401 
402 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
403 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
404 
405 	/* Set RQ to the min of mode, tstatus and mstatus */
406 	rq = AGP_MODE_GET_RQ(mode);
407 	if (AGP_MODE_GET_RQ(tstatus) < rq)
408 		rq = AGP_MODE_GET_RQ(tstatus);
409 	if (AGP_MODE_GET_RQ(mstatus) < rq)
410 		rq = AGP_MODE_GET_RQ(mstatus);
411 
412 	/* Set SBA if all three can deal with SBA */
413 	sba = (AGP_MODE_GET_SBA(tstatus)
414 	       & AGP_MODE_GET_SBA(mstatus)
415 	       & AGP_MODE_GET_SBA(mode));
416 
417 	/* Similar for FW */
418 	fw = (AGP_MODE_GET_FW(tstatus)
419 	       & AGP_MODE_GET_FW(mstatus)
420 	       & AGP_MODE_GET_FW(mode));
421 
422 	/* Figure out the max rate */
423 	rate = (AGP_MODE_GET_RATE(tstatus)
424 		& AGP_MODE_GET_RATE(mstatus)
425 		& AGP_MODE_GET_RATE(mode));
426 	if (rate & AGP_MODE_V2_RATE_4x)
427 		rate = AGP_MODE_V2_RATE_4x;
428 	else if (rate & AGP_MODE_V2_RATE_2x)
429 		rate = AGP_MODE_V2_RATE_2x;
430 	else
431 		rate = AGP_MODE_V2_RATE_1x;
432 	if (bootverbose)
433 		device_printf(dev, "Setting AGP v2 mode %d\n", rate);
434 
435 	/* Construct the new mode word and tell the hardware */
436 	command = 0;
437 	command = AGP_MODE_SET_RQ(0, rq);
438 	command = AGP_MODE_SET_SBA(command, sba);
439 	command = AGP_MODE_SET_FW(command, fw);
440 	command = AGP_MODE_SET_RATE(command, rate);
441 	command = AGP_MODE_SET_AGP(command, 1);
442 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
443 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
444 
445 	return 0;
446 }
447 
448 int
449 agp_generic_enable(device_t dev, u_int32_t mode)
450 {
451 	device_t mdev = agp_find_display();
452 	u_int32_t tstatus, mstatus;
453 
454 	if (!mdev) {
455 		AGP_DPF("can't find display\n");
456 		return ENXIO;
457 	}
458 
459 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
460 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
461 
462 	/*
463 	 * Check display and bridge for AGP v3 support.  AGP v3 allows
464 	 * more variety in topology than v2, e.g. multiple AGP devices
465 	 * attached to one bridge, or multiple AGP bridges in one
466 	 * system.  This doesn't attempt to address those situations,
467 	 * but should work fine for a classic single AGP slot system
468 	 * with AGP v3.
469 	 */
470 	if (AGP_MODE_GET_MODE_3(mode) &&
471 	    AGP_MODE_GET_MODE_3(tstatus) &&
472 	    AGP_MODE_GET_MODE_3(mstatus))
473 		return (agp_v3_enable(dev, mdev, mode));
474 	else
475 		return (agp_v2_enable(dev, mdev, mode));
476 }
477 
478 struct agp_memory *
479 agp_generic_alloc_memory(device_t dev, int type, vm_size_t size)
480 {
481 	struct agp_softc *sc = device_get_softc(dev);
482 	struct agp_memory *mem;
483 
484 	if ((size & (AGP_PAGE_SIZE - 1)) != 0)
485 		return 0;
486 
487 	if (sc->as_allocated + size > sc->as_maxmem)
488 		return 0;
489 
490 	if (type != 0) {
491 		printf("agp_generic_alloc_memory: unsupported type %d\n",
492 		       type);
493 		return 0;
494 	}
495 
496 	mem = malloc(sizeof *mem, M_AGP, M_WAITOK);
497 	mem->am_id = sc->as_nextid++;
498 	mem->am_size = size;
499 	mem->am_type = 0;
500 	mem->am_obj = vm_object_allocate(OBJT_DEFAULT, atop(round_page(size)));
501 	mem->am_physical = 0;
502 	mem->am_offset = 0;
503 	mem->am_is_bound = 0;
504 	TAILQ_INSERT_TAIL(&sc->as_memory, mem, am_link);
505 	sc->as_allocated += size;
506 
507 	return mem;
508 }
509 
510 int
511 agp_generic_free_memory(device_t dev, struct agp_memory *mem)
512 {
513 	struct agp_softc *sc = device_get_softc(dev);
514 
515 	if (mem->am_is_bound)
516 		return EBUSY;
517 
518 	sc->as_allocated -= mem->am_size;
519 	TAILQ_REMOVE(&sc->as_memory, mem, am_link);
520 	vm_object_deallocate(mem->am_obj);
521 	free(mem, M_AGP);
522 	return 0;
523 }
524 
525 int
526 agp_generic_bind_memory(device_t dev, struct agp_memory *mem,
527 			vm_offset_t offset)
528 {
529 	struct agp_softc *sc = device_get_softc(dev);
530 	vm_offset_t i, j, k;
531 	vm_page_t m;
532 	int error;
533 
534 	/* Do some sanity checks first. */
535 	if ((offset & (AGP_PAGE_SIZE - 1)) != 0 ||
536 	    offset + mem->am_size > AGP_GET_APERTURE(dev)) {
537 		device_printf(dev, "binding memory at bad offset %#x\n",
538 		    (int)offset);
539 		return EINVAL;
540 	}
541 
542 	/*
543 	 * Allocate the pages early, before acquiring the lock,
544 	 * because vm_page_grab() may sleep and we can't hold a mutex
545 	 * while sleeping.
546 	 */
547 	VM_OBJECT_LOCK(mem->am_obj);
548 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
549 		/*
550 		 * Find a page from the object and wire it
551 		 * down. This page will be mapped using one or more
552 		 * entries in the GATT (assuming that PAGE_SIZE >=
553 		 * AGP_PAGE_SIZE. If this is the first call to bind,
554 		 * the pages will be allocated and zeroed.
555 		 */
556 		m = vm_page_grab(mem->am_obj, OFF_TO_IDX(i),
557 		    VM_ALLOC_WIRED | VM_ALLOC_ZERO | VM_ALLOC_RETRY);
558 		AGP_DPF("found page pa=%#jx\n", (uintmax_t)VM_PAGE_TO_PHYS(m));
559 	}
560 	VM_OBJECT_UNLOCK(mem->am_obj);
561 
562 	mtx_lock(&sc->as_lock);
563 
564 	if (mem->am_is_bound) {
565 		device_printf(dev, "memory already bound\n");
566 		error = EINVAL;
567 		VM_OBJECT_LOCK(mem->am_obj);
568 		i = 0;
569 		goto bad;
570 	}
571 
572 	/*
573 	 * Bind the individual pages and flush the chipset's
574 	 * TLB.
575 	 */
576 	VM_OBJECT_LOCK(mem->am_obj);
577 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
578 		m = vm_page_lookup(mem->am_obj, OFF_TO_IDX(i));
579 
580 		/*
581 		 * Install entries in the GATT, making sure that if
582 		 * AGP_PAGE_SIZE < PAGE_SIZE and mem->am_size is not
583 		 * aligned to PAGE_SIZE, we don't modify too many GATT
584 		 * entries.
585 		 */
586 		for (j = 0; j < PAGE_SIZE && i + j < mem->am_size;
587 		     j += AGP_PAGE_SIZE) {
588 			vm_offset_t pa = VM_PAGE_TO_PHYS(m) + j;
589 			AGP_DPF("binding offset %#jx to pa %#jx\n",
590 				(uintmax_t)offset + i + j, (uintmax_t)pa);
591 			error = AGP_BIND_PAGE(dev, offset + i + j, pa);
592 			if (error) {
593 				/*
594 				 * Bail out. Reverse all the mappings
595 				 * and unwire the pages.
596 				 */
597 				for (k = 0; k < i + j; k += AGP_PAGE_SIZE)
598 					AGP_UNBIND_PAGE(dev, offset + k);
599 				goto bad;
600 			}
601 		}
602 		vm_page_wakeup(m);
603 	}
604 	VM_OBJECT_UNLOCK(mem->am_obj);
605 
606 	/*
607 	 * Flush the cpu cache since we are providing a new mapping
608 	 * for these pages.
609 	 */
610 	agp_flush_cache();
611 
612 	/*
613 	 * Make sure the chipset gets the new mappings.
614 	 */
615 	AGP_FLUSH_TLB(dev);
616 
617 	mem->am_offset = offset;
618 	mem->am_is_bound = 1;
619 
620 	mtx_unlock(&sc->as_lock);
621 
622 	return 0;
623 bad:
624 	mtx_unlock(&sc->as_lock);
625 	VM_OBJECT_LOCK_ASSERT(mem->am_obj, MA_OWNED);
626 	for (k = 0; k < mem->am_size; k += PAGE_SIZE) {
627 		m = vm_page_lookup(mem->am_obj, OFF_TO_IDX(k));
628 		if (k >= i)
629 			vm_page_wakeup(m);
630 		vm_page_lock(m);
631 		vm_page_unwire(m, 0);
632 		vm_page_unlock(m);
633 	}
634 	VM_OBJECT_UNLOCK(mem->am_obj);
635 
636 	return error;
637 }
638 
639 int
640 agp_generic_unbind_memory(device_t dev, struct agp_memory *mem)
641 {
642 	struct agp_softc *sc = device_get_softc(dev);
643 	vm_page_t m;
644 	int i;
645 
646 	mtx_lock(&sc->as_lock);
647 
648 	if (!mem->am_is_bound) {
649 		device_printf(dev, "memory is not bound\n");
650 		mtx_unlock(&sc->as_lock);
651 		return EINVAL;
652 	}
653 
654 
655 	/*
656 	 * Unbind the individual pages and flush the chipset's
657 	 * TLB. Unwire the pages so they can be swapped.
658 	 */
659 	for (i = 0; i < mem->am_size; i += AGP_PAGE_SIZE)
660 		AGP_UNBIND_PAGE(dev, mem->am_offset + i);
661 	VM_OBJECT_LOCK(mem->am_obj);
662 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
663 		m = vm_page_lookup(mem->am_obj, atop(i));
664 		vm_page_lock(m);
665 		vm_page_unwire(m, 0);
666 		vm_page_unlock(m);
667 	}
668 	VM_OBJECT_UNLOCK(mem->am_obj);
669 
670 	agp_flush_cache();
671 	AGP_FLUSH_TLB(dev);
672 
673 	mem->am_offset = 0;
674 	mem->am_is_bound = 0;
675 
676 	mtx_unlock(&sc->as_lock);
677 
678 	return 0;
679 }
680 
681 /* Helper functions for implementing user/kernel api */
682 
683 static int
684 agp_acquire_helper(device_t dev, enum agp_acquire_state state)
685 {
686 	struct agp_softc *sc = device_get_softc(dev);
687 
688 	if (sc->as_state != AGP_ACQUIRE_FREE)
689 		return EBUSY;
690 	sc->as_state = state;
691 
692 	return 0;
693 }
694 
695 static int
696 agp_release_helper(device_t dev, enum agp_acquire_state state)
697 {
698 	struct agp_softc *sc = device_get_softc(dev);
699 
700 	if (sc->as_state == AGP_ACQUIRE_FREE)
701 		return 0;
702 
703 	if (sc->as_state != state)
704 		return EBUSY;
705 
706 	sc->as_state = AGP_ACQUIRE_FREE;
707 	return 0;
708 }
709 
710 static struct agp_memory *
711 agp_find_memory(device_t dev, int id)
712 {
713 	struct agp_softc *sc = device_get_softc(dev);
714 	struct agp_memory *mem;
715 
716 	AGP_DPF("searching for memory block %d\n", id);
717 	TAILQ_FOREACH(mem, &sc->as_memory, am_link) {
718 		AGP_DPF("considering memory block %d\n", mem->am_id);
719 		if (mem->am_id == id)
720 			return mem;
721 	}
722 	return 0;
723 }
724 
725 /* Implementation of the userland ioctl api */
726 
727 static int
728 agp_info_user(device_t dev, agp_info *info)
729 {
730 	struct agp_softc *sc = device_get_softc(dev);
731 
732 	bzero(info, sizeof *info);
733 	info->bridge_id = pci_get_devid(dev);
734 	info->agp_mode =
735 	    pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
736 	if (sc->as_aperture)
737 		info->aper_base = rman_get_start(sc->as_aperture);
738 	else
739 		info->aper_base = 0;
740 	info->aper_size = AGP_GET_APERTURE(dev) >> 20;
741 	info->pg_total = info->pg_system = sc->as_maxmem >> AGP_PAGE_SHIFT;
742 	info->pg_used = sc->as_allocated >> AGP_PAGE_SHIFT;
743 
744 	return 0;
745 }
746 
747 static int
748 agp_setup_user(device_t dev, agp_setup *setup)
749 {
750 	return AGP_ENABLE(dev, setup->agp_mode);
751 }
752 
753 static int
754 agp_allocate_user(device_t dev, agp_allocate *alloc)
755 {
756 	struct agp_memory *mem;
757 
758 	mem = AGP_ALLOC_MEMORY(dev,
759 			       alloc->type,
760 			       alloc->pg_count << AGP_PAGE_SHIFT);
761 	if (mem) {
762 		alloc->key = mem->am_id;
763 		alloc->physical = mem->am_physical;
764 		return 0;
765 	} else {
766 		return ENOMEM;
767 	}
768 }
769 
770 static int
771 agp_deallocate_user(device_t dev, int id)
772 {
773 	struct agp_memory *mem = agp_find_memory(dev, id);
774 
775 	if (mem) {
776 		AGP_FREE_MEMORY(dev, mem);
777 		return 0;
778 	} else {
779 		return ENOENT;
780 	}
781 }
782 
783 static int
784 agp_bind_user(device_t dev, agp_bind *bind)
785 {
786 	struct agp_memory *mem = agp_find_memory(dev, bind->key);
787 
788 	if (!mem)
789 		return ENOENT;
790 
791 	return AGP_BIND_MEMORY(dev, mem, bind->pg_start << AGP_PAGE_SHIFT);
792 }
793 
794 static int
795 agp_unbind_user(device_t dev, agp_unbind *unbind)
796 {
797 	struct agp_memory *mem = agp_find_memory(dev, unbind->key);
798 
799 	if (!mem)
800 		return ENOENT;
801 
802 	return AGP_UNBIND_MEMORY(dev, mem);
803 }
804 
805 static int
806 agp_chipset_flush(device_t dev)
807 {
808 
809 	return (AGP_CHIPSET_FLUSH(dev));
810 }
811 
812 static int
813 agp_open(struct cdev *kdev, int oflags, int devtype, struct thread *td)
814 {
815 	device_t dev = kdev->si_drv1;
816 	struct agp_softc *sc = device_get_softc(dev);
817 
818 	if (!sc->as_isopen) {
819 		sc->as_isopen = 1;
820 		device_busy(dev);
821 	}
822 
823 	return 0;
824 }
825 
826 static int
827 agp_close(struct cdev *kdev, int fflag, int devtype, struct thread *td)
828 {
829 	device_t dev = kdev->si_drv1;
830 	struct agp_softc *sc = device_get_softc(dev);
831 	struct agp_memory *mem;
832 
833 	/*
834 	 * Clear the GATT and force release on last close
835 	 */
836 	while ((mem = TAILQ_FIRST(&sc->as_memory)) != 0) {
837 		if (mem->am_is_bound)
838 			AGP_UNBIND_MEMORY(dev, mem);
839 		AGP_FREE_MEMORY(dev, mem);
840 	}
841 	if (sc->as_state == AGP_ACQUIRE_USER)
842 		agp_release_helper(dev, AGP_ACQUIRE_USER);
843 	sc->as_isopen = 0;
844 	device_unbusy(dev);
845 
846 	return 0;
847 }
848 
849 static int
850 agp_ioctl(struct cdev *kdev, u_long cmd, caddr_t data, int fflag, struct thread *td)
851 {
852 	device_t dev = kdev->si_drv1;
853 
854 	switch (cmd) {
855 	case AGPIOC_INFO:
856 		return agp_info_user(dev, (agp_info *) data);
857 
858 	case AGPIOC_ACQUIRE:
859 		return agp_acquire_helper(dev, AGP_ACQUIRE_USER);
860 
861 	case AGPIOC_RELEASE:
862 		return agp_release_helper(dev, AGP_ACQUIRE_USER);
863 
864 	case AGPIOC_SETUP:
865 		return agp_setup_user(dev, (agp_setup *)data);
866 
867 	case AGPIOC_ALLOCATE:
868 		return agp_allocate_user(dev, (agp_allocate *)data);
869 
870 	case AGPIOC_DEALLOCATE:
871 		return agp_deallocate_user(dev, *(int *) data);
872 
873 	case AGPIOC_BIND:
874 		return agp_bind_user(dev, (agp_bind *)data);
875 
876 	case AGPIOC_UNBIND:
877 		return agp_unbind_user(dev, (agp_unbind *)data);
878 
879 	case AGPIOC_CHIPSET_FLUSH:
880 		return agp_chipset_flush(dev);
881 	}
882 
883 	return EINVAL;
884 }
885 
886 static int
887 agp_mmap(struct cdev *kdev, vm_ooffset_t offset, vm_paddr_t *paddr,
888     int prot, vm_memattr_t *memattr)
889 {
890 	device_t dev = kdev->si_drv1;
891 	struct agp_softc *sc = device_get_softc(dev);
892 
893 	if (offset > AGP_GET_APERTURE(dev))
894 		return -1;
895 	if (sc->as_aperture == NULL)
896 		return -1;
897 	*paddr = rman_get_start(sc->as_aperture) + offset;
898 	return 0;
899 }
900 
901 /* Implementation of the kernel api */
902 
903 device_t
904 agp_find_device()
905 {
906 	device_t *children, child;
907 	int i, count;
908 
909 	if (!agp_devclass)
910 		return NULL;
911 	if (devclass_get_devices(agp_devclass, &children, &count) != 0)
912 		return NULL;
913 	child = NULL;
914 	for (i = 0; i < count; i++) {
915 		if (device_is_attached(children[i])) {
916 			child = children[i];
917 			break;
918 		}
919 	}
920 	free(children, M_TEMP);
921 	return child;
922 }
923 
924 enum agp_acquire_state
925 agp_state(device_t dev)
926 {
927 	struct agp_softc *sc = device_get_softc(dev);
928 	return sc->as_state;
929 }
930 
931 void
932 agp_get_info(device_t dev, struct agp_info *info)
933 {
934 	struct agp_softc *sc = device_get_softc(dev);
935 
936 	info->ai_mode =
937 		pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
938 	if (sc->as_aperture != NULL)
939 		info->ai_aperture_base = rman_get_start(sc->as_aperture);
940 	else
941 		info->ai_aperture_base = 0;
942 	info->ai_aperture_size = AGP_GET_APERTURE(dev);
943 	info->ai_memory_allowed = sc->as_maxmem;
944 	info->ai_memory_used = sc->as_allocated;
945 }
946 
947 int
948 agp_acquire(device_t dev)
949 {
950 	return agp_acquire_helper(dev, AGP_ACQUIRE_KERNEL);
951 }
952 
953 int
954 agp_release(device_t dev)
955 {
956 	return agp_release_helper(dev, AGP_ACQUIRE_KERNEL);
957 }
958 
959 int
960 agp_enable(device_t dev, u_int32_t mode)
961 {
962 	return AGP_ENABLE(dev, mode);
963 }
964 
965 void *agp_alloc_memory(device_t dev, int type, vm_size_t bytes)
966 {
967 	return  (void *) AGP_ALLOC_MEMORY(dev, type, bytes);
968 }
969 
970 void agp_free_memory(device_t dev, void *handle)
971 {
972 	struct agp_memory *mem = (struct agp_memory *) handle;
973 	AGP_FREE_MEMORY(dev, mem);
974 }
975 
976 int agp_bind_memory(device_t dev, void *handle, vm_offset_t offset)
977 {
978 	struct agp_memory *mem = (struct agp_memory *) handle;
979 	return AGP_BIND_MEMORY(dev, mem, offset);
980 }
981 
982 int agp_unbind_memory(device_t dev, void *handle)
983 {
984 	struct agp_memory *mem = (struct agp_memory *) handle;
985 	return AGP_UNBIND_MEMORY(dev, mem);
986 }
987 
988 void agp_memory_info(device_t dev, void *handle, struct
989 		     agp_memory_info *mi)
990 {
991 	struct agp_memory *mem = (struct agp_memory *) handle;
992 
993 	mi->ami_size = mem->am_size;
994 	mi->ami_physical = mem->am_physical;
995 	mi->ami_offset = mem->am_offset;
996 	mi->ami_is_bound = mem->am_is_bound;
997 }
998