xref: /dragonfly/sys/dev/agp/agp.c (revision 9bb2a92d)
1 /*-
2  * Copyright (c) 2000 Doug Rabson
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  *	$FreeBSD: src/sys/pci/agp.c,v 1.3.2.4 2002/08/11 19:58:12 alc Exp $
27  *	$DragonFly: src/sys/dev/agp/agp.c,v 1.10 2004/03/01 06:33:13 dillon Exp $
28  */
29 
30 #include "opt_bus.h"
31 #include "opt_pci.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/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/proc.h>
43 
44 #include <bus/pci/pcivar.h>
45 #include <bus/pci/pcireg.h>
46 #include "agppriv.h"
47 #include "agpvar.h"
48 #include "agpreg.h"
49 
50 #include <vm/vm.h>
51 #include <vm/vm_object.h>
52 #include <vm/vm_page.h>
53 #include <vm/vm_pageout.h>
54 #include <vm/pmap.h>
55 
56 #include <machine/md_var.h>
57 #include <machine/bus.h>
58 #include <machine/resource.h>
59 #include <sys/rman.h>
60 
61 MODULE_VERSION(agp, 1);
62 
63 MALLOC_DEFINE(M_AGP, "agp", "AGP data structures");
64 
65 #define CDEV_MAJOR	148
66 				/* agp_drv.c */
67 static d_open_t agp_open;
68 static d_close_t agp_close;
69 static d_ioctl_t agp_ioctl;
70 static d_mmap_t agp_mmap;
71 
72 static struct cdevsw agp_cdevsw = {
73 	/* name */	"agp",
74 	/* maj */	CDEV_MAJOR,
75 	/* flags */	D_TTY,
76 	/* port */	NULL,
77 	/* autoq */	0,
78 
79 	/* open */	agp_open,
80 	/* close */	agp_close,
81 	/* read */	noread,
82 	/* write */	nowrite,
83 	/* ioctl */	agp_ioctl,
84 	/* poll */	nopoll,
85 	/* mmap */	agp_mmap,
86 	/* strategy */	nostrategy,
87 	/* dump */	nodump,
88 	/* psize */	nopsize
89 };
90 
91 static devclass_t agp_devclass;
92 #define KDEV2DEV(kdev)	devclass_get_device(agp_devclass, minor(kdev))
93 
94 /* Helper functions for implementing chipset mini drivers. */
95 
96 void
97 agp_flush_cache()
98 {
99 #ifdef __i386__
100 	wbinvd();
101 #endif
102 }
103 
104 u_int8_t
105 agp_find_caps(device_t dev)
106 {
107 	u_int32_t status;
108 	u_int8_t ptr, next;
109 
110 	/*
111 	 * Check the CAP_LIST bit of the PCI status register first.
112 	 */
113 	status = pci_read_config(dev, PCIR_STATUS, 2);
114 	if (!(status & 0x10))
115 		return 0;
116 
117 	/*
118 	 * Traverse the capabilities list.
119 	 */
120 	for (ptr = pci_read_config(dev, AGP_CAPPTR, 1);
121 	     ptr != 0;
122 	     ptr = next) {
123 		u_int32_t capid = pci_read_config(dev, ptr, 4);
124 		next = AGP_CAPID_GET_NEXT_PTR(capid);
125 
126 		/*
127 		 * If this capability entry ID is 2, then we are done.
128 		 */
129 		if (AGP_CAPID_GET_CAP_ID(capid) == 2)
130 			return ptr;
131 	}
132 
133 	return 0;
134 }
135 
136 /*
137  * Find an AGP display device (if any).
138  */
139 static device_t
140 agp_find_display(void)
141 {
142 	devclass_t pci = devclass_find("pci");
143 	device_t bus, dev = 0;
144 	device_t *kids;
145 	int busnum, numkids, i;
146 
147 	for (busnum = 0; busnum < devclass_get_maxunit(pci); busnum++) {
148 		bus = devclass_get_device(pci, busnum);
149 		if (!bus)
150 			continue;
151 		device_get_children(bus, &kids, &numkids);
152 		for (i = 0; i < numkids; i++) {
153 			dev = kids[i];
154 			if (pci_get_class(dev) == PCIC_DISPLAY
155 			    && pci_get_subclass(dev) == PCIS_DISPLAY_VGA)
156 				if (agp_find_caps(dev)) {
157 					free(kids, M_TEMP);
158 					return dev;
159 				}
160 
161 		}
162 		free(kids, M_TEMP);
163 	}
164 
165 	return 0;
166 }
167 
168 struct agp_gatt *
169 agp_alloc_gatt(device_t dev)
170 {
171 	u_int32_t apsize = AGP_GET_APERTURE(dev);
172 	u_int32_t entries = apsize >> AGP_PAGE_SHIFT;
173 	struct agp_gatt *gatt;
174 
175 	if (bootverbose)
176 		device_printf(dev,
177 			      "allocating GATT for aperture of size %dM\n",
178 			      apsize / (1024*1024));
179 
180 	if (entries == 0) {
181 		device_printf(dev, "bad aperture size\n");
182 		return NULL;
183 	}
184 
185 	gatt = malloc(sizeof(struct agp_gatt), M_AGP, M_NOWAIT);
186 	if (!gatt)
187 		return 0;
188 
189 	gatt->ag_entries = entries;
190 	gatt->ag_virtual = contigmalloc(entries * sizeof(u_int32_t), M_AGP, 0,
191 					0, ~0, PAGE_SIZE, 0);
192 	if (!gatt->ag_virtual) {
193 		if (bootverbose)
194 			device_printf(dev, "contiguous allocation failed\n");
195 		free(gatt, M_AGP);
196 		return 0;
197 	}
198 	bzero(gatt->ag_virtual, entries * sizeof(u_int32_t));
199 	gatt->ag_physical = vtophys((vm_offset_t) gatt->ag_virtual);
200 	agp_flush_cache();
201 
202 	return gatt;
203 }
204 
205 void
206 agp_free_gatt(struct agp_gatt *gatt)
207 {
208 	contigfree(gatt->ag_virtual,
209 		   gatt->ag_entries * sizeof(u_int32_t), M_AGP);
210 	free(gatt, M_AGP);
211 }
212 
213 static int agp_max[][2] = {
214 	{0,	0},
215 	{32,	4},
216 	{64,	28},
217 	{128,	96},
218 	{256,	204},
219 	{512,	440},
220 	{1024,	942},
221 	{2048,	1920},
222 	{4096,	3932}
223 };
224 #define agp_max_size	(sizeof(agp_max) / sizeof(agp_max[0]))
225 
226 int
227 agp_generic_attach(device_t dev)
228 {
229 	struct agp_softc *sc = device_get_softc(dev);
230 	int rid, memsize, i;
231 
232 	/*
233 	 * Find and map the aperture.
234 	 */
235 	rid = AGP_APBASE;
236 	sc->as_aperture = bus_alloc_resource(dev, SYS_RES_MEMORY, &rid,
237 					     0, ~0, 1, RF_ACTIVE);
238 	if (!sc->as_aperture)
239 		return ENOMEM;
240 
241 	/*
242 	 * Work out an upper bound for agp memory allocation. This
243 	 * uses a heurisitc table from the Linux driver.
244 	 */
245 	memsize = ptoa(Maxmem) >> 20;
246 	for (i = 0; i < agp_max_size; i++) {
247 		if (memsize <= agp_max[i][0])
248 			break;
249 	}
250 	if (i == agp_max_size) i = agp_max_size - 1;
251 	sc->as_maxmem = agp_max[i][1] << 20U;
252 
253 	/*
254 	 * The lock is used to prevent re-entry to
255 	 * agp_generic_bind_memory() since that function can sleep.
256 	 */
257 	lockinit(&sc->as_lock, PCATCH, "agplk", 0, 0);
258 
259 	/*
260 	 * Initialise stuff for the userland device.
261 	 */
262 	agp_devclass = devclass_find("agp");
263 	TAILQ_INIT(&sc->as_memory);
264 	sc->as_nextid = 1;
265 
266 	sc->as_devnode = make_dev(&agp_cdevsw,
267 				  device_get_unit(dev),
268 				  UID_ROOT,
269 				  GID_WHEEL,
270 				  0600,
271 				  "agpgart");
272 
273 	return 0;
274 }
275 
276 int
277 agp_generic_detach(device_t dev)
278 {
279 	struct agp_softc *sc = device_get_softc(dev);
280 	bus_release_resource(dev, SYS_RES_MEMORY, AGP_APBASE, sc->as_aperture);
281 	lockmgr(&sc->as_lock, LK_DRAIN, NULL, curthread); /* XXX */
282 	destroy_dev(sc->as_devnode);
283 	agp_flush_cache();
284 	return 0;
285 }
286 
287 /*
288  * This does the enable logic for v3, with the same topology
289  * restrictions as in place for v2 -- one bus, one device on the bus.
290  */
291 static int
292 agp_v3_enable(device_t dev, device_t mdev, u_int32_t mode)
293 {
294 	u_int32_t tstatus, mstatus;
295 	u_int32_t command;
296 	int rq, sba, fw, rate, arqsz, cal;
297 
298 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
299 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
300 
301 	/* Set RQ to the min of mode, tstatus and mstatus */
302 	rq = AGP_MODE_GET_RQ(mode);
303 	if (AGP_MODE_GET_RQ(tstatus) < rq)
304 		rq = AGP_MODE_GET_RQ(tstatus);
305 	if (AGP_MODE_GET_RQ(mstatus) < rq)
306 		rq = AGP_MODE_GET_RQ(mstatus);
307 
308 	/*
309 	 * ARQSZ - Set the value to the maximum one.
310 	 * Don't allow the mode register to override values.
311 	 */
312 	arqsz = AGP_MODE_GET_ARQSZ(mode);
313 	if (AGP_MODE_GET_ARQSZ(tstatus) > rq)
314 		rq = AGP_MODE_GET_ARQSZ(tstatus);
315 	if (AGP_MODE_GET_ARQSZ(mstatus) > rq)
316 		rq = AGP_MODE_GET_ARQSZ(mstatus);
317 
318 	/* Calibration cycle - don't allow override by mode register */
319 	cal = AGP_MODE_GET_CAL(tstatus);
320 	if (AGP_MODE_GET_CAL(mstatus) < cal)
321 		cal = AGP_MODE_GET_CAL(mstatus);
322 
323 	/* SBA must be supported for AGP v3. */
324 	sba = 1;
325 
326 	/* Set FW if all three support it. */
327 	fw = (AGP_MODE_GET_FW(tstatus)
328 	       & AGP_MODE_GET_FW(mstatus)
329 	       & AGP_MODE_GET_FW(mode));
330 
331 	/* Figure out the max rate */
332 	rate = (AGP_MODE_GET_RATE(tstatus)
333 		& AGP_MODE_GET_RATE(mstatus)
334 		& AGP_MODE_GET_RATE(mode));
335 	if (rate & AGP_MODE_V3_RATE_8x)
336 		rate = AGP_MODE_V3_RATE_8x;
337 	else
338 		rate = AGP_MODE_V3_RATE_4x;
339 	if (bootverbose)
340 		device_printf(dev, "Setting AGP v3 mode %d\n", rate * 4);
341 
342 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, 0, 4);
343 
344 	/* Construct the new mode word and tell the hardware */
345 	command = AGP_MODE_SET_RQ(0, rq);
346 	command = AGP_MODE_SET_ARQSZ(command, arqsz);
347 	command = AGP_MODE_SET_CAL(command, cal);
348 	command = AGP_MODE_SET_SBA(command, sba);
349 	command = AGP_MODE_SET_FW(command, fw);
350 	command = AGP_MODE_SET_RATE(command, rate);
351 	command = AGP_MODE_SET_AGP(command, 1);
352 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
353 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
354 
355 	return 0;
356 }
357 
358 static int
359 agp_v2_enable(device_t dev, device_t mdev, u_int32_t mode)
360 {
361 	u_int32_t tstatus, mstatus;
362 	u_int32_t command;
363 	int rq, sba, fw, rate;
364 
365 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
366 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
367 
368 	/* Set RQ to the min of mode, tstatus and mstatus */
369 	rq = AGP_MODE_GET_RQ(mode);
370 	if (AGP_MODE_GET_RQ(tstatus) < rq)
371 		rq = AGP_MODE_GET_RQ(tstatus);
372 	if (AGP_MODE_GET_RQ(mstatus) < rq)
373 		rq = AGP_MODE_GET_RQ(mstatus);
374 
375 	/* Set SBA if all three can deal with SBA */
376 	sba = (AGP_MODE_GET_SBA(tstatus)
377 	       & AGP_MODE_GET_SBA(mstatus)
378 	       & AGP_MODE_GET_SBA(mode));
379 
380 	/* Similar for FW */
381 	fw = (AGP_MODE_GET_FW(tstatus)
382 	       & AGP_MODE_GET_FW(mstatus)
383 	       & AGP_MODE_GET_FW(mode));
384 
385 	/* Figure out the max rate */
386 	rate = (AGP_MODE_GET_RATE(tstatus)
387 		& AGP_MODE_GET_RATE(mstatus)
388 		& AGP_MODE_GET_RATE(mode));
389 	if (rate & AGP_MODE_V2_RATE_4x)
390 		rate = AGP_MODE_V2_RATE_4x;
391 	else if (rate & AGP_MODE_V2_RATE_2x)
392 		rate = AGP_MODE_V2_RATE_2x;
393 	else
394 		rate = AGP_MODE_V2_RATE_1x;
395 	if (bootverbose)
396 		device_printf(dev, "Setting AGP v2 mode %d\n", rate);
397 
398 	/* Construct the new mode word and tell the hardware */
399 	command = AGP_MODE_SET_RQ(0, rq);
400 	command = AGP_MODE_SET_SBA(command, sba);
401 	command = AGP_MODE_SET_FW(command, fw);
402 	command = AGP_MODE_SET_RATE(command, rate);
403 	command = AGP_MODE_SET_AGP(command, 1);
404 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
405 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
406 
407 	return 0;
408 }
409 
410 int
411 agp_generic_enable(device_t dev, u_int32_t mode)
412 {
413 	device_t mdev = agp_find_display();
414 	u_int32_t tstatus, mstatus;
415 
416 	if (!mdev) {
417 		AGP_DPF("can't find display\n");
418 		return ENXIO;
419 	}
420 
421 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
422 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
423 
424 	/*
425 	 * Check display and bridge for AGP v3 support.  AGP v3 allows
426 	 * more variety in topology than v2, e.g. multiple AGP devices
427 	 * attached to one bridge, or multiple AGP bridges in one
428 	 * system.  This doesn't attempt to address those situations,
429 	 * but should work fine for a classic single AGP slot system
430 	 * with AGP v3.
431 	 */
432 	if (AGP_MODE_GET_MODE_3(tstatus) && AGP_MODE_GET_MODE_3(mstatus))
433 		return (agp_v3_enable(dev, mdev, mode));
434 	else
435 		return (agp_v2_enable(dev, mdev, mode));
436 }
437 
438 struct agp_memory *
439 agp_generic_alloc_memory(device_t dev, int type, vm_size_t size)
440 {
441 	struct agp_softc *sc = device_get_softc(dev);
442 	struct agp_memory *mem;
443 
444 	if ((size & (AGP_PAGE_SIZE - 1)) != 0)
445 		return 0;
446 
447 	if (sc->as_allocated + size > sc->as_maxmem)
448 		return 0;
449 
450 	if (type != 0) {
451 		printf("agp_generic_alloc_memory: unsupported type %d\n",
452 		       type);
453 		return 0;
454 	}
455 
456 	mem = malloc(sizeof *mem, M_AGP, M_WAITOK);
457 	mem->am_id = sc->as_nextid++;
458 	mem->am_size = size;
459 	mem->am_type = 0;
460 	mem->am_obj = vm_object_allocate(OBJT_DEFAULT, atop(round_page(size)));
461 	mem->am_physical = 0;
462 	mem->am_offset = 0;
463 	mem->am_is_bound = 0;
464 	TAILQ_INSERT_TAIL(&sc->as_memory, mem, am_link);
465 	sc->as_allocated += size;
466 
467 	return mem;
468 }
469 
470 int
471 agp_generic_free_memory(device_t dev, struct agp_memory *mem)
472 {
473 	struct agp_softc *sc = device_get_softc(dev);
474 
475 	if (mem->am_is_bound)
476 		return EBUSY;
477 
478 	sc->as_allocated -= mem->am_size;
479 	TAILQ_REMOVE(&sc->as_memory, mem, am_link);
480 	vm_object_deallocate(mem->am_obj);
481 	free(mem, M_AGP);
482 	return 0;
483 }
484 
485 int
486 agp_generic_bind_memory(device_t dev, struct agp_memory *mem,
487 			vm_offset_t offset)
488 {
489 	struct agp_softc *sc = device_get_softc(dev);
490 	vm_offset_t i, j, k;
491 	vm_page_t m;
492 	int error;
493 
494 	lockmgr(&sc->as_lock, LK_EXCLUSIVE, NULL, curthread); /* XXX */
495 
496 	if (mem->am_is_bound) {
497 		device_printf(dev, "memory already bound\n");
498 		return EINVAL;
499 	}
500 
501 	if (offset < 0
502 	    || (offset & (AGP_PAGE_SIZE - 1)) != 0
503 	    || offset + mem->am_size > AGP_GET_APERTURE(dev)) {
504 		device_printf(dev, "binding memory at bad offset %#x\n",
505 			      (int) offset);
506 		return EINVAL;
507 	}
508 
509 	/*
510 	 * Bind the individual pages and flush the chipset's
511 	 * TLB.
512 	 *
513 	 * XXX Presumably, this needs to be the pci address on alpha
514 	 * (i.e. use alpha_XXX_dmamap()). I don't have access to any
515 	 * alpha AGP hardware to check.
516 	 */
517 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
518 		/*
519 		 * Find a page from the object and wire it
520 		 * down. This page will be mapped using one or more
521 		 * entries in the GATT (assuming that PAGE_SIZE >=
522 		 * AGP_PAGE_SIZE. If this is the first call to bind,
523 		 * the pages will be allocated and zeroed.
524 		 */
525 		m = vm_page_grab(mem->am_obj, OFF_TO_IDX(i),
526 			 VM_ALLOC_NORMAL | VM_ALLOC_ZERO | VM_ALLOC_RETRY);
527 		if ((m->flags & PG_ZERO) == 0)
528 			vm_page_zero_fill(m);
529 		AGP_DPF("found page pa=%#x\n", VM_PAGE_TO_PHYS(m));
530 		vm_page_wire(m);
531 
532 		/*
533 		 * Install entries in the GATT, making sure that if
534 		 * AGP_PAGE_SIZE < PAGE_SIZE and mem->am_size is not
535 		 * aligned to PAGE_SIZE, we don't modify too many GATT
536 		 * entries.
537 		 */
538 		for (j = 0; j < PAGE_SIZE && i + j < mem->am_size;
539 		     j += AGP_PAGE_SIZE) {
540 			vm_offset_t pa = VM_PAGE_TO_PHYS(m) + j;
541 			AGP_DPF("binding offset %#x to pa %#x\n",
542 				offset + i + j, pa);
543 			error = AGP_BIND_PAGE(dev, offset + i + j, pa);
544 			if (error) {
545 				/*
546 				 * Bail out. Reverse all the mappings
547 				 * and unwire the pages.
548 				 */
549 				vm_page_wakeup(m);
550 				for (k = 0; k < i + j; k += AGP_PAGE_SIZE)
551 					AGP_UNBIND_PAGE(dev, offset + k);
552 				for (k = 0; k <= i; k += PAGE_SIZE) {
553 					m = vm_page_lookup(mem->am_obj,
554 							   OFF_TO_IDX(k));
555 					vm_page_unwire(m, 0);
556 				}
557 				lockmgr(&sc->as_lock, LK_RELEASE, NULL, curthread); /* XXX */
558 				return error;
559 			}
560 		}
561 		vm_page_wakeup(m);
562 	}
563 
564 	/*
565 	 * Flush the cpu cache since we are providing a new mapping
566 	 * for these pages.
567 	 */
568 	agp_flush_cache();
569 
570 	/*
571 	 * Make sure the chipset gets the new mappings.
572 	 */
573 	AGP_FLUSH_TLB(dev);
574 
575 	mem->am_offset = offset;
576 	mem->am_is_bound = 1;
577 
578 	lockmgr(&sc->as_lock, LK_RELEASE, NULL, curthread); /* XXX */
579 
580 	return 0;
581 }
582 
583 int
584 agp_generic_unbind_memory(device_t dev, struct agp_memory *mem)
585 {
586 	struct agp_softc *sc = device_get_softc(dev);
587 	vm_page_t m;
588 	int i;
589 
590 	lockmgr(&sc->as_lock, LK_EXCLUSIVE, NULL, curthread); /* XXX */
591 
592 	if (!mem->am_is_bound) {
593 		device_printf(dev, "memory is not bound\n");
594 		return EINVAL;
595 	}
596 
597 
598 	/*
599 	 * Unbind the individual pages and flush the chipset's
600 	 * TLB. Unwire the pages so they can be swapped.
601 	 */
602 	for (i = 0; i < mem->am_size; i += AGP_PAGE_SIZE)
603 		AGP_UNBIND_PAGE(dev, mem->am_offset + i);
604 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
605 		m = vm_page_lookup(mem->am_obj, atop(i));
606 		vm_page_unwire(m, 0);
607 	}
608 
609 	agp_flush_cache();
610 	AGP_FLUSH_TLB(dev);
611 
612 	mem->am_offset = 0;
613 	mem->am_is_bound = 0;
614 
615 	lockmgr(&sc->as_lock, LK_RELEASE, NULL, curthread); /* XXX */
616 
617 	return 0;
618 }
619 
620 /* Helper functions for implementing user/kernel api */
621 
622 static int
623 agp_acquire_helper(device_t dev, enum agp_acquire_state state)
624 {
625 	struct agp_softc *sc = device_get_softc(dev);
626 
627 	if (sc->as_state != AGP_ACQUIRE_FREE)
628 		return EBUSY;
629 	sc->as_state = state;
630 
631 	return 0;
632 }
633 
634 static int
635 agp_release_helper(device_t dev, enum agp_acquire_state state)
636 {
637 	struct agp_softc *sc = device_get_softc(dev);
638 
639 	if (sc->as_state == AGP_ACQUIRE_FREE)
640 		return 0;
641 
642 	if (sc->as_state != state)
643 		return EBUSY;
644 
645 	sc->as_state = AGP_ACQUIRE_FREE;
646 	return 0;
647 }
648 
649 static struct agp_memory *
650 agp_find_memory(device_t dev, int id)
651 {
652 	struct agp_softc *sc = device_get_softc(dev);
653 	struct agp_memory *mem;
654 
655 	AGP_DPF("searching for memory block %d\n", id);
656 	TAILQ_FOREACH(mem, &sc->as_memory, am_link) {
657 		AGP_DPF("considering memory block %d\n", mem->am_id);
658 		if (mem->am_id == id)
659 			return mem;
660 	}
661 	return 0;
662 }
663 
664 /* Implementation of the userland ioctl api */
665 
666 static int
667 agp_info_user(device_t dev, agp_info *info)
668 {
669 	struct agp_softc *sc = device_get_softc(dev);
670 
671 	bzero(info, sizeof *info);
672 	info->bridge_id = pci_get_devid(dev);
673 	info->agp_mode =
674 	    pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
675 	info->aper_base = rman_get_start(sc->as_aperture);
676 	info->aper_size = AGP_GET_APERTURE(dev) >> 20;
677 	info->pg_total = info->pg_system = sc->as_maxmem >> AGP_PAGE_SHIFT;
678 	info->pg_used = sc->as_allocated >> AGP_PAGE_SHIFT;
679 
680 	return 0;
681 }
682 
683 static int
684 agp_setup_user(device_t dev, agp_setup *setup)
685 {
686 	return AGP_ENABLE(dev, setup->agp_mode);
687 }
688 
689 static int
690 agp_allocate_user(device_t dev, agp_allocate *alloc)
691 {
692 	struct agp_memory *mem;
693 
694 	mem = AGP_ALLOC_MEMORY(dev,
695 			       alloc->type,
696 			       alloc->pg_count << AGP_PAGE_SHIFT);
697 	if (mem) {
698 		alloc->key = mem->am_id;
699 		alloc->physical = mem->am_physical;
700 		return 0;
701 	} else {
702 		return ENOMEM;
703 	}
704 }
705 
706 static int
707 agp_deallocate_user(device_t dev, int id)
708 {
709 	struct agp_memory *mem = agp_find_memory(dev, id);;
710 
711 	if (mem) {
712 		AGP_FREE_MEMORY(dev, mem);
713 		return 0;
714 	} else {
715 		return ENOENT;
716 	}
717 }
718 
719 static int
720 agp_bind_user(device_t dev, agp_bind *bind)
721 {
722 	struct agp_memory *mem = agp_find_memory(dev, bind->key);
723 
724 	if (!mem)
725 		return ENOENT;
726 
727 	return AGP_BIND_MEMORY(dev, mem, bind->pg_start << AGP_PAGE_SHIFT);
728 }
729 
730 static int
731 agp_unbind_user(device_t dev, agp_unbind *unbind)
732 {
733 	struct agp_memory *mem = agp_find_memory(dev, unbind->key);
734 
735 	if (!mem)
736 		return ENOENT;
737 
738 	return AGP_UNBIND_MEMORY(dev, mem);
739 }
740 
741 static int
742 agp_open(dev_t kdev, int oflags, int devtype, struct thread *td)
743 {
744 	device_t dev = KDEV2DEV(kdev);
745 	struct agp_softc *sc = device_get_softc(dev);
746 
747 	if (!sc->as_isopen) {
748 		sc->as_isopen = 1;
749 		device_busy(dev);
750 	}
751 
752 	return 0;
753 }
754 
755 static int
756 agp_close(dev_t kdev, int fflag, int devtype, struct thread *td)
757 {
758 	device_t dev = KDEV2DEV(kdev);
759 	struct agp_softc *sc = device_get_softc(dev);
760 	struct agp_memory *mem;
761 
762 	/*
763 	 * Clear the GATT and force release on last close
764 	 */
765 	while ((mem = TAILQ_FIRST(&sc->as_memory)) != 0) {
766 		if (mem->am_is_bound)
767 			AGP_UNBIND_MEMORY(dev, mem);
768 		AGP_FREE_MEMORY(dev, mem);
769 	}
770 	if (sc->as_state == AGP_ACQUIRE_USER)
771 		agp_release_helper(dev, AGP_ACQUIRE_USER);
772 	sc->as_isopen = 0;
773 	device_unbusy(dev);
774 
775 	return 0;
776 }
777 
778 static int
779 agp_ioctl(dev_t kdev, u_long cmd, caddr_t data, int fflag, struct thread *td)
780 {
781 	device_t dev = KDEV2DEV(kdev);
782 
783 	switch (cmd) {
784 	case AGPIOC_INFO:
785 		return agp_info_user(dev, (agp_info *) data);
786 
787 	case AGPIOC_ACQUIRE:
788 		return agp_acquire_helper(dev, AGP_ACQUIRE_USER);
789 
790 	case AGPIOC_RELEASE:
791 		return agp_release_helper(dev, AGP_ACQUIRE_USER);
792 
793 	case AGPIOC_SETUP:
794 		return agp_setup_user(dev, (agp_setup *)data);
795 
796 	case AGPIOC_ALLOCATE:
797 		return agp_allocate_user(dev, (agp_allocate *)data);
798 
799 	case AGPIOC_DEALLOCATE:
800 		return agp_deallocate_user(dev, *(int *) data);
801 
802 	case AGPIOC_BIND:
803 		return agp_bind_user(dev, (agp_bind *)data);
804 
805 	case AGPIOC_UNBIND:
806 		return agp_unbind_user(dev, (agp_unbind *)data);
807 
808 	}
809 
810 	return EINVAL;
811 }
812 
813 static int
814 agp_mmap(dev_t kdev, vm_offset_t offset, int prot)
815 {
816 	device_t dev = KDEV2DEV(kdev);
817 	struct agp_softc *sc = device_get_softc(dev);
818 
819 	if (offset > AGP_GET_APERTURE(dev))
820 		return -1;
821 	return atop(rman_get_start(sc->as_aperture) + offset);
822 }
823 
824 /* Implementation of the kernel api */
825 
826 device_t
827 agp_find_device()
828 {
829 	if (!agp_devclass)
830 		return 0;
831 	return devclass_get_device(agp_devclass, 0);
832 }
833 
834 enum agp_acquire_state
835 agp_state(device_t dev)
836 {
837 	struct agp_softc *sc = device_get_softc(dev);
838 	return sc->as_state;
839 }
840 
841 void
842 agp_get_info(device_t dev, struct agp_info *info)
843 {
844 	struct agp_softc *sc = device_get_softc(dev);
845 
846 	info->ai_mode =
847 		pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
848 	info->ai_aperture_base = rman_get_start(sc->as_aperture);
849 	info->ai_aperture_size = (rman_get_end(sc->as_aperture)
850 				  - rman_get_start(sc->as_aperture)) + 1;
851 	info->ai_aperture_va = (vm_offset_t) rman_get_virtual(sc->as_aperture);
852 	info->ai_memory_allowed = sc->as_maxmem;
853 	info->ai_memory_used = sc->as_allocated;
854 }
855 
856 int
857 agp_acquire(device_t dev)
858 {
859 	return agp_acquire_helper(dev, AGP_ACQUIRE_KERNEL);
860 }
861 
862 int
863 agp_release(device_t dev)
864 {
865 	return agp_release_helper(dev, AGP_ACQUIRE_KERNEL);
866 }
867 
868 int
869 agp_enable(device_t dev, u_int32_t mode)
870 {
871 	return AGP_ENABLE(dev, mode);
872 }
873 
874 void *agp_alloc_memory(device_t dev, int type, vm_size_t bytes)
875 {
876 	return  (void *) AGP_ALLOC_MEMORY(dev, type, bytes);
877 }
878 
879 void agp_free_memory(device_t dev, void *handle)
880 {
881 	struct agp_memory *mem = (struct agp_memory *) handle;
882 	AGP_FREE_MEMORY(dev, mem);
883 }
884 
885 int agp_bind_memory(device_t dev, void *handle, vm_offset_t offset)
886 {
887 	struct agp_memory *mem = (struct agp_memory *) handle;
888 	return AGP_BIND_MEMORY(dev, mem, offset);
889 }
890 
891 int agp_unbind_memory(device_t dev, void *handle)
892 {
893 	struct agp_memory *mem = (struct agp_memory *) handle;
894 	return AGP_UNBIND_MEMORY(dev, mem);
895 }
896 
897 void agp_memory_info(device_t dev, void *handle, struct
898 		     agp_memory_info *mi)
899 {
900 	struct agp_memory *mem = (struct agp_memory *) handle;
901 
902 	mi->ami_size = mem->am_size;
903 	mi->ami_physical = mem->am_physical;
904 	mi->ami_offset = mem->am_offset;
905 	mi->ami_is_bound = mem->am_is_bound;
906 }
907