xref: /freebsd/sys/dev/agp/agp.c (revision 43d55325406e96e37be661de52289c2592c82ec9)
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 
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 #include <sys/rwlock.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_extern.h>
54 #include <vm/vm_kern.h>
55 #include <vm/vm_param.h>
56 #include <vm/vm_object.h>
57 #include <vm/vm_page.h>
58 #include <vm/vm_pageout.h>
59 #include <vm/pmap.h>
60 
61 #include <machine/bus.h>
62 #include <machine/resource.h>
63 #include <sys/rman.h>
64 
65 MODULE_VERSION(agp, 1);
66 
67 MALLOC_DEFINE(M_AGP, "agp", "AGP data structures");
68 
69 				/* agp_drv.c */
70 static d_open_t agp_open;
71 static d_close_t agp_close;
72 static d_ioctl_t agp_ioctl;
73 static d_mmap_t agp_mmap;
74 
75 static struct cdevsw agp_cdevsw = {
76 	.d_version =	D_VERSION,
77 	.d_flags =	D_NEEDGIANT,
78 	.d_open =	agp_open,
79 	.d_close =	agp_close,
80 	.d_ioctl =	agp_ioctl,
81 	.d_mmap =	agp_mmap,
82 	.d_name =	"agp",
83 };
84 
85 static devclass_t agp_devclass;
86 
87 /* Helper functions for implementing chipset mini drivers. */
88 
89 u_int8_t
90 agp_find_caps(device_t dev)
91 {
92 	int capreg;
93 
94 
95 	if (pci_find_cap(dev, PCIY_AGP, &capreg) != 0)
96 		capreg = 0;
97 	return (capreg);
98 }
99 
100 /*
101  * Find an AGP display device (if any).
102  */
103 static device_t
104 agp_find_display(void)
105 {
106 	devclass_t pci = devclass_find("pci");
107 	device_t bus, dev = 0;
108 	device_t *kids;
109 	int busnum, numkids, i;
110 
111 	for (busnum = 0; busnum < devclass_get_maxunit(pci); busnum++) {
112 		bus = devclass_get_device(pci, busnum);
113 		if (!bus)
114 			continue;
115 		if (device_get_children(bus, &kids, &numkids) != 0)
116 			continue;
117 		for (i = 0; i < numkids; i++) {
118 			dev = kids[i];
119 			if (pci_get_class(dev) == PCIC_DISPLAY
120 			    && pci_get_subclass(dev) == PCIS_DISPLAY_VGA)
121 				if (agp_find_caps(dev)) {
122 					free(kids, M_TEMP);
123 					return dev;
124 				}
125 
126 		}
127 		free(kids, M_TEMP);
128 	}
129 
130 	return 0;
131 }
132 
133 struct agp_gatt *
134 agp_alloc_gatt(device_t dev)
135 {
136 	u_int32_t apsize = AGP_GET_APERTURE(dev);
137 	u_int32_t entries = apsize >> AGP_PAGE_SHIFT;
138 	struct agp_gatt *gatt;
139 
140 	if (bootverbose)
141 		device_printf(dev,
142 			      "allocating GATT for aperture of size %dM\n",
143 			      apsize / (1024*1024));
144 
145 	if (entries == 0) {
146 		device_printf(dev, "bad aperture size\n");
147 		return NULL;
148 	}
149 
150 	gatt = malloc(sizeof(struct agp_gatt), M_AGP, M_NOWAIT);
151 	if (!gatt)
152 		return 0;
153 
154 	gatt->ag_entries = entries;
155 	gatt->ag_virtual = (void *)kmem_alloc_contig(kernel_arena,
156 	    entries * sizeof(u_int32_t), M_NOWAIT | M_ZERO, 0, ~0, PAGE_SIZE,
157 	    0, VM_MEMATTR_WRITE_COMBINING);
158 	if (!gatt->ag_virtual) {
159 		if (bootverbose)
160 			device_printf(dev, "contiguous allocation failed\n");
161 		free(gatt, M_AGP);
162 		return 0;
163 	}
164 	gatt->ag_physical = vtophys((vm_offset_t) gatt->ag_virtual);
165 
166 	return gatt;
167 }
168 
169 void
170 agp_free_gatt(struct agp_gatt *gatt)
171 {
172 	kmem_free(kernel_arena, (vm_offset_t)gatt->ag_virtual,
173 	    gatt->ag_entries * sizeof(u_int32_t));
174 	free(gatt, M_AGP);
175 }
176 
177 static u_int agp_max[][2] = {
178 	{0,	0},
179 	{32,	4},
180 	{64,	28},
181 	{128,	96},
182 	{256,	204},
183 	{512,	440},
184 	{1024,	942},
185 	{2048,	1920},
186 	{4096,	3932}
187 };
188 #define agp_max_size	(sizeof(agp_max) / sizeof(agp_max[0]))
189 
190 /**
191  * Sets the PCI resource which represents the AGP aperture.
192  *
193  * If not called, the default AGP aperture resource of AGP_APBASE will
194  * be used.  Must be called before agp_generic_attach().
195  */
196 void
197 agp_set_aperture_resource(device_t dev, int rid)
198 {
199 	struct agp_softc *sc = device_get_softc(dev);
200 
201 	sc->as_aperture_rid = rid;
202 }
203 
204 int
205 agp_generic_attach(device_t dev)
206 {
207 	struct agp_softc *sc = device_get_softc(dev);
208 	int i;
209 	u_int memsize;
210 
211 	/*
212 	 * Find and map the aperture, RF_SHAREABLE for DRM but not RF_ACTIVE
213 	 * because the kernel doesn't need to map it.
214 	 */
215 
216 	if (sc->as_aperture_rid != -1) {
217 		if (sc->as_aperture_rid == 0)
218 			sc->as_aperture_rid = AGP_APBASE;
219 
220 		sc->as_aperture = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
221 		    &sc->as_aperture_rid, RF_SHAREABLE);
222 		if (!sc->as_aperture)
223 			return ENOMEM;
224 	}
225 
226 	/*
227 	 * Work out an upper bound for agp memory allocation. This
228 	 * uses a heurisitc table from the Linux driver.
229 	 */
230 	memsize = ptoa(realmem) >> 20;
231 	for (i = 0; i < agp_max_size; i++) {
232 		if (memsize <= agp_max[i][0])
233 			break;
234 	}
235 	if (i == agp_max_size)
236 		i = agp_max_size - 1;
237 	sc->as_maxmem = agp_max[i][1] << 20U;
238 
239 	/*
240 	 * The lock is used to prevent re-entry to
241 	 * agp_generic_bind_memory() since that function can sleep.
242 	 */
243 	mtx_init(&sc->as_lock, "agp lock", NULL, MTX_DEF);
244 
245 	/*
246 	 * Initialise stuff for the userland device.
247 	 */
248 	agp_devclass = devclass_find("agp");
249 	TAILQ_INIT(&sc->as_memory);
250 	sc->as_nextid = 1;
251 
252 	sc->as_devnode = make_dev(&agp_cdevsw,
253 	    0, UID_ROOT, GID_WHEEL, 0600, "agpgart");
254 	sc->as_devnode->si_drv1 = dev;
255 
256 	return 0;
257 }
258 
259 void
260 agp_free_cdev(device_t dev)
261 {
262 	struct agp_softc *sc = device_get_softc(dev);
263 
264 	destroy_dev(sc->as_devnode);
265 }
266 
267 void
268 agp_free_res(device_t dev)
269 {
270 	struct agp_softc *sc = device_get_softc(dev);
271 
272 	if (sc->as_aperture != NULL)
273 		bus_release_resource(dev, SYS_RES_MEMORY, sc->as_aperture_rid,
274 		    sc->as_aperture);
275 	mtx_destroy(&sc->as_lock);
276 }
277 
278 int
279 agp_generic_detach(device_t dev)
280 {
281 
282 	agp_free_cdev(dev);
283 	agp_free_res(dev);
284 	return 0;
285 }
286 
287 /**
288  * Default AGP aperture size detection which simply returns the size of
289  * the aperture's PCI resource.
290  */
291 u_int32_t
292 agp_generic_get_aperture(device_t dev)
293 {
294 	struct agp_softc *sc = device_get_softc(dev);
295 
296 	return rman_get_size(sc->as_aperture);
297 }
298 
299 /**
300  * Default AGP aperture size setting function, which simply doesn't allow
301  * changes to resource size.
302  */
303 int
304 agp_generic_set_aperture(device_t dev, u_int32_t aperture)
305 {
306 	u_int32_t current_aperture;
307 
308 	current_aperture = AGP_GET_APERTURE(dev);
309 	if (current_aperture != aperture)
310 		return EINVAL;
311 	else
312 		return 0;
313 }
314 
315 /*
316  * This does the enable logic for v3, with the same topology
317  * restrictions as in place for v2 -- one bus, one device on the bus.
318  */
319 static int
320 agp_v3_enable(device_t dev, device_t mdev, u_int32_t mode)
321 {
322 	u_int32_t tstatus, mstatus;
323 	u_int32_t command;
324 	int rq, sba, fw, rate, arqsz, cal;
325 
326 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
327 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
328 
329 	/* Set RQ to the min of mode, tstatus and mstatus */
330 	rq = AGP_MODE_GET_RQ(mode);
331 	if (AGP_MODE_GET_RQ(tstatus) < rq)
332 		rq = AGP_MODE_GET_RQ(tstatus);
333 	if (AGP_MODE_GET_RQ(mstatus) < rq)
334 		rq = AGP_MODE_GET_RQ(mstatus);
335 
336 	/*
337 	 * ARQSZ - Set the value to the maximum one.
338 	 * Don't allow the mode register to override values.
339 	 */
340 	arqsz = AGP_MODE_GET_ARQSZ(mode);
341 	if (AGP_MODE_GET_ARQSZ(tstatus) > rq)
342 		rq = AGP_MODE_GET_ARQSZ(tstatus);
343 	if (AGP_MODE_GET_ARQSZ(mstatus) > rq)
344 		rq = AGP_MODE_GET_ARQSZ(mstatus);
345 
346 	/* Calibration cycle - don't allow override by mode register */
347 	cal = AGP_MODE_GET_CAL(tstatus);
348 	if (AGP_MODE_GET_CAL(mstatus) < cal)
349 		cal = AGP_MODE_GET_CAL(mstatus);
350 
351 	/* SBA must be supported for AGP v3. */
352 	sba = 1;
353 
354 	/* Set FW if all three support it. */
355 	fw = (AGP_MODE_GET_FW(tstatus)
356 	       & AGP_MODE_GET_FW(mstatus)
357 	       & AGP_MODE_GET_FW(mode));
358 
359 	/* Figure out the max rate */
360 	rate = (AGP_MODE_GET_RATE(tstatus)
361 		& AGP_MODE_GET_RATE(mstatus)
362 		& AGP_MODE_GET_RATE(mode));
363 	if (rate & AGP_MODE_V3_RATE_8x)
364 		rate = AGP_MODE_V3_RATE_8x;
365 	else
366 		rate = AGP_MODE_V3_RATE_4x;
367 	if (bootverbose)
368 		device_printf(dev, "Setting AGP v3 mode %d\n", rate * 4);
369 
370 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, 0, 4);
371 
372 	/* Construct the new mode word and tell the hardware */
373 	command = 0;
374 	command = AGP_MODE_SET_RQ(0, rq);
375 	command = AGP_MODE_SET_ARQSZ(command, arqsz);
376 	command = AGP_MODE_SET_CAL(command, cal);
377 	command = AGP_MODE_SET_SBA(command, sba);
378 	command = AGP_MODE_SET_FW(command, fw);
379 	command = AGP_MODE_SET_RATE(command, rate);
380 	command = AGP_MODE_SET_MODE_3(command, 1);
381 	command = AGP_MODE_SET_AGP(command, 1);
382 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
383 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
384 
385 	return 0;
386 }
387 
388 static int
389 agp_v2_enable(device_t dev, device_t mdev, u_int32_t mode)
390 {
391 	u_int32_t tstatus, mstatus;
392 	u_int32_t command;
393 	int rq, sba, fw, rate;
394 
395 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
396 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
397 
398 	/* Set RQ to the min of mode, tstatus and mstatus */
399 	rq = AGP_MODE_GET_RQ(mode);
400 	if (AGP_MODE_GET_RQ(tstatus) < rq)
401 		rq = AGP_MODE_GET_RQ(tstatus);
402 	if (AGP_MODE_GET_RQ(mstatus) < rq)
403 		rq = AGP_MODE_GET_RQ(mstatus);
404 
405 	/* Set SBA if all three can deal with SBA */
406 	sba = (AGP_MODE_GET_SBA(tstatus)
407 	       & AGP_MODE_GET_SBA(mstatus)
408 	       & AGP_MODE_GET_SBA(mode));
409 
410 	/* Similar for FW */
411 	fw = (AGP_MODE_GET_FW(tstatus)
412 	       & AGP_MODE_GET_FW(mstatus)
413 	       & AGP_MODE_GET_FW(mode));
414 
415 	/* Figure out the max rate */
416 	rate = (AGP_MODE_GET_RATE(tstatus)
417 		& AGP_MODE_GET_RATE(mstatus)
418 		& AGP_MODE_GET_RATE(mode));
419 	if (rate & AGP_MODE_V2_RATE_4x)
420 		rate = AGP_MODE_V2_RATE_4x;
421 	else if (rate & AGP_MODE_V2_RATE_2x)
422 		rate = AGP_MODE_V2_RATE_2x;
423 	else
424 		rate = AGP_MODE_V2_RATE_1x;
425 	if (bootverbose)
426 		device_printf(dev, "Setting AGP v2 mode %d\n", rate);
427 
428 	/* Construct the new mode word and tell the hardware */
429 	command = 0;
430 	command = AGP_MODE_SET_RQ(0, rq);
431 	command = AGP_MODE_SET_SBA(command, sba);
432 	command = AGP_MODE_SET_FW(command, fw);
433 	command = AGP_MODE_SET_RATE(command, rate);
434 	command = AGP_MODE_SET_AGP(command, 1);
435 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
436 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
437 
438 	return 0;
439 }
440 
441 int
442 agp_generic_enable(device_t dev, u_int32_t mode)
443 {
444 	device_t mdev = agp_find_display();
445 	u_int32_t tstatus, mstatus;
446 
447 	if (!mdev) {
448 		AGP_DPF("can't find display\n");
449 		return ENXIO;
450 	}
451 
452 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
453 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
454 
455 	/*
456 	 * Check display and bridge for AGP v3 support.  AGP v3 allows
457 	 * more variety in topology than v2, e.g. multiple AGP devices
458 	 * attached to one bridge, or multiple AGP bridges in one
459 	 * system.  This doesn't attempt to address those situations,
460 	 * but should work fine for a classic single AGP slot system
461 	 * with AGP v3.
462 	 */
463 	if (AGP_MODE_GET_MODE_3(mode) &&
464 	    AGP_MODE_GET_MODE_3(tstatus) &&
465 	    AGP_MODE_GET_MODE_3(mstatus))
466 		return (agp_v3_enable(dev, mdev, mode));
467 	else
468 		return (agp_v2_enable(dev, mdev, mode));
469 }
470 
471 struct agp_memory *
472 agp_generic_alloc_memory(device_t dev, int type, vm_size_t size)
473 {
474 	struct agp_softc *sc = device_get_softc(dev);
475 	struct agp_memory *mem;
476 
477 	if ((size & (AGP_PAGE_SIZE - 1)) != 0)
478 		return 0;
479 
480 	if (size > sc->as_maxmem - sc->as_allocated)
481 		return 0;
482 
483 	if (type != 0) {
484 		printf("agp_generic_alloc_memory: unsupported type %d\n",
485 		       type);
486 		return 0;
487 	}
488 
489 	mem = malloc(sizeof *mem, M_AGP, M_WAITOK);
490 	mem->am_id = sc->as_nextid++;
491 	mem->am_size = size;
492 	mem->am_type = 0;
493 	mem->am_obj = vm_object_allocate(OBJT_DEFAULT, atop(round_page(size)));
494 	mem->am_physical = 0;
495 	mem->am_offset = 0;
496 	mem->am_is_bound = 0;
497 	TAILQ_INSERT_TAIL(&sc->as_memory, mem, am_link);
498 	sc->as_allocated += size;
499 
500 	return mem;
501 }
502 
503 int
504 agp_generic_free_memory(device_t dev, struct agp_memory *mem)
505 {
506 	struct agp_softc *sc = device_get_softc(dev);
507 
508 	if (mem->am_is_bound)
509 		return EBUSY;
510 
511 	sc->as_allocated -= mem->am_size;
512 	TAILQ_REMOVE(&sc->as_memory, mem, am_link);
513 	vm_object_deallocate(mem->am_obj);
514 	free(mem, M_AGP);
515 	return 0;
516 }
517 
518 int
519 agp_generic_bind_memory(device_t dev, struct agp_memory *mem,
520 			vm_offset_t offset)
521 {
522 	struct agp_softc *sc = device_get_softc(dev);
523 	vm_offset_t i, j, k;
524 	vm_page_t m;
525 	int error;
526 
527 	/* Do some sanity checks first. */
528 	if ((offset & (AGP_PAGE_SIZE - 1)) != 0 ||
529 	    offset + mem->am_size > AGP_GET_APERTURE(dev)) {
530 		device_printf(dev, "binding memory at bad offset %#x\n",
531 		    (int)offset);
532 		return EINVAL;
533 	}
534 
535 	/*
536 	 * Allocate the pages early, before acquiring the lock,
537 	 * because vm_page_grab() may sleep and we can't hold a mutex
538 	 * while sleeping.
539 	 */
540 	VM_OBJECT_WLOCK(mem->am_obj);
541 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
542 		/*
543 		 * Find a page from the object and wire it
544 		 * down. This page will be mapped using one or more
545 		 * entries in the GATT (assuming that PAGE_SIZE >=
546 		 * AGP_PAGE_SIZE. If this is the first call to bind,
547 		 * the pages will be allocated and zeroed.
548 		 */
549 		m = vm_page_grab(mem->am_obj, OFF_TO_IDX(i),
550 		    VM_ALLOC_WIRED | VM_ALLOC_ZERO);
551 		AGP_DPF("found page pa=%#jx\n", (uintmax_t)VM_PAGE_TO_PHYS(m));
552 	}
553 	VM_OBJECT_WUNLOCK(mem->am_obj);
554 
555 	mtx_lock(&sc->as_lock);
556 
557 	if (mem->am_is_bound) {
558 		device_printf(dev, "memory already bound\n");
559 		error = EINVAL;
560 		VM_OBJECT_WLOCK(mem->am_obj);
561 		i = 0;
562 		goto bad;
563 	}
564 
565 	/*
566 	 * Bind the individual pages and flush the chipset's
567 	 * TLB.
568 	 */
569 	VM_OBJECT_WLOCK(mem->am_obj);
570 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
571 		m = vm_page_lookup(mem->am_obj, OFF_TO_IDX(i));
572 
573 		/*
574 		 * Install entries in the GATT, making sure that if
575 		 * AGP_PAGE_SIZE < PAGE_SIZE and mem->am_size is not
576 		 * aligned to PAGE_SIZE, we don't modify too many GATT
577 		 * entries.
578 		 */
579 		for (j = 0; j < PAGE_SIZE && i + j < mem->am_size;
580 		     j += AGP_PAGE_SIZE) {
581 			vm_offset_t pa = VM_PAGE_TO_PHYS(m) + j;
582 			AGP_DPF("binding offset %#jx to pa %#jx\n",
583 				(uintmax_t)offset + i + j, (uintmax_t)pa);
584 			error = AGP_BIND_PAGE(dev, offset + i + j, pa);
585 			if (error) {
586 				/*
587 				 * Bail out. Reverse all the mappings
588 				 * and unwire the pages.
589 				 */
590 				for (k = 0; k < i + j; k += AGP_PAGE_SIZE)
591 					AGP_UNBIND_PAGE(dev, offset + k);
592 				goto bad;
593 			}
594 		}
595 		vm_page_xunbusy(m);
596 	}
597 	VM_OBJECT_WUNLOCK(mem->am_obj);
598 
599 	/*
600 	 * Make sure the chipset gets the new mappings.
601 	 */
602 	AGP_FLUSH_TLB(dev);
603 
604 	mem->am_offset = offset;
605 	mem->am_is_bound = 1;
606 
607 	mtx_unlock(&sc->as_lock);
608 
609 	return 0;
610 bad:
611 	mtx_unlock(&sc->as_lock);
612 	VM_OBJECT_ASSERT_WLOCKED(mem->am_obj);
613 	for (k = 0; k < mem->am_size; k += PAGE_SIZE) {
614 		m = vm_page_lookup(mem->am_obj, OFF_TO_IDX(k));
615 		if (k >= i)
616 			vm_page_xunbusy(m);
617 		vm_page_lock(m);
618 		vm_page_unwire(m, PQ_INACTIVE);
619 		vm_page_unlock(m);
620 	}
621 	VM_OBJECT_WUNLOCK(mem->am_obj);
622 
623 	return error;
624 }
625 
626 int
627 agp_generic_unbind_memory(device_t dev, struct agp_memory *mem)
628 {
629 	struct agp_softc *sc = device_get_softc(dev);
630 	vm_page_t m;
631 	int i;
632 
633 	mtx_lock(&sc->as_lock);
634 
635 	if (!mem->am_is_bound) {
636 		device_printf(dev, "memory is not bound\n");
637 		mtx_unlock(&sc->as_lock);
638 		return EINVAL;
639 	}
640 
641 
642 	/*
643 	 * Unbind the individual pages and flush the chipset's
644 	 * TLB. Unwire the pages so they can be swapped.
645 	 */
646 	for (i = 0; i < mem->am_size; i += AGP_PAGE_SIZE)
647 		AGP_UNBIND_PAGE(dev, mem->am_offset + i);
648 
649 	AGP_FLUSH_TLB(dev);
650 
651 	VM_OBJECT_WLOCK(mem->am_obj);
652 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
653 		m = vm_page_lookup(mem->am_obj, atop(i));
654 		vm_page_lock(m);
655 		vm_page_unwire(m, PQ_INACTIVE);
656 		vm_page_unlock(m);
657 	}
658 	VM_OBJECT_WUNLOCK(mem->am_obj);
659 
660 	mem->am_offset = 0;
661 	mem->am_is_bound = 0;
662 
663 	mtx_unlock(&sc->as_lock);
664 
665 	return 0;
666 }
667 
668 /* Helper functions for implementing user/kernel api */
669 
670 static int
671 agp_acquire_helper(device_t dev, enum agp_acquire_state state)
672 {
673 	struct agp_softc *sc = device_get_softc(dev);
674 
675 	if (sc->as_state != AGP_ACQUIRE_FREE)
676 		return EBUSY;
677 	sc->as_state = state;
678 
679 	return 0;
680 }
681 
682 static int
683 agp_release_helper(device_t dev, enum agp_acquire_state state)
684 {
685 	struct agp_softc *sc = device_get_softc(dev);
686 
687 	if (sc->as_state == AGP_ACQUIRE_FREE)
688 		return 0;
689 
690 	if (sc->as_state != state)
691 		return EBUSY;
692 
693 	sc->as_state = AGP_ACQUIRE_FREE;
694 	return 0;
695 }
696 
697 static struct agp_memory *
698 agp_find_memory(device_t dev, int id)
699 {
700 	struct agp_softc *sc = device_get_softc(dev);
701 	struct agp_memory *mem;
702 
703 	AGP_DPF("searching for memory block %d\n", id);
704 	TAILQ_FOREACH(mem, &sc->as_memory, am_link) {
705 		AGP_DPF("considering memory block %d\n", mem->am_id);
706 		if (mem->am_id == id)
707 			return mem;
708 	}
709 	return 0;
710 }
711 
712 /* Implementation of the userland ioctl api */
713 
714 static int
715 agp_info_user(device_t dev, agp_info *info)
716 {
717 	struct agp_softc *sc = device_get_softc(dev);
718 
719 	bzero(info, sizeof *info);
720 	info->bridge_id = pci_get_devid(dev);
721 	info->agp_mode =
722 	    pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
723 	if (sc->as_aperture)
724 		info->aper_base = rman_get_start(sc->as_aperture);
725 	else
726 		info->aper_base = 0;
727 	info->aper_size = AGP_GET_APERTURE(dev) >> 20;
728 	info->pg_total = info->pg_system = sc->as_maxmem >> AGP_PAGE_SHIFT;
729 	info->pg_used = sc->as_allocated >> AGP_PAGE_SHIFT;
730 
731 	return 0;
732 }
733 
734 static int
735 agp_setup_user(device_t dev, agp_setup *setup)
736 {
737 	return AGP_ENABLE(dev, setup->agp_mode);
738 }
739 
740 static int
741 agp_allocate_user(device_t dev, agp_allocate *alloc)
742 {
743 	struct agp_memory *mem;
744 
745 	mem = AGP_ALLOC_MEMORY(dev,
746 			       alloc->type,
747 			       alloc->pg_count << AGP_PAGE_SHIFT);
748 	if (mem) {
749 		alloc->key = mem->am_id;
750 		alloc->physical = mem->am_physical;
751 		return 0;
752 	} else {
753 		return ENOMEM;
754 	}
755 }
756 
757 static int
758 agp_deallocate_user(device_t dev, int id)
759 {
760 	struct agp_memory *mem = agp_find_memory(dev, id);
761 
762 	if (mem) {
763 		AGP_FREE_MEMORY(dev, mem);
764 		return 0;
765 	} else {
766 		return ENOENT;
767 	}
768 }
769 
770 static int
771 agp_bind_user(device_t dev, agp_bind *bind)
772 {
773 	struct agp_memory *mem = agp_find_memory(dev, bind->key);
774 
775 	if (!mem)
776 		return ENOENT;
777 
778 	return AGP_BIND_MEMORY(dev, mem, bind->pg_start << AGP_PAGE_SHIFT);
779 }
780 
781 static int
782 agp_unbind_user(device_t dev, agp_unbind *unbind)
783 {
784 	struct agp_memory *mem = agp_find_memory(dev, unbind->key);
785 
786 	if (!mem)
787 		return ENOENT;
788 
789 	return AGP_UNBIND_MEMORY(dev, mem);
790 }
791 
792 static int
793 agp_chipset_flush(device_t dev)
794 {
795 
796 	return (AGP_CHIPSET_FLUSH(dev));
797 }
798 
799 static int
800 agp_open(struct cdev *kdev, int oflags, int devtype, struct thread *td)
801 {
802 	device_t dev = kdev->si_drv1;
803 	struct agp_softc *sc = device_get_softc(dev);
804 
805 	if (!sc->as_isopen) {
806 		sc->as_isopen = 1;
807 		device_busy(dev);
808 	}
809 
810 	return 0;
811 }
812 
813 static int
814 agp_close(struct cdev *kdev, int fflag, int devtype, struct thread *td)
815 {
816 	device_t dev = kdev->si_drv1;
817 	struct agp_softc *sc = device_get_softc(dev);
818 	struct agp_memory *mem;
819 
820 	/*
821 	 * Clear the GATT and force release on last close
822 	 */
823 	while ((mem = TAILQ_FIRST(&sc->as_memory)) != 0) {
824 		if (mem->am_is_bound)
825 			AGP_UNBIND_MEMORY(dev, mem);
826 		AGP_FREE_MEMORY(dev, mem);
827 	}
828 	if (sc->as_state == AGP_ACQUIRE_USER)
829 		agp_release_helper(dev, AGP_ACQUIRE_USER);
830 	sc->as_isopen = 0;
831 	device_unbusy(dev);
832 
833 	return 0;
834 }
835 
836 static int
837 agp_ioctl(struct cdev *kdev, u_long cmd, caddr_t data, int fflag, struct thread *td)
838 {
839 	device_t dev = kdev->si_drv1;
840 
841 	switch (cmd) {
842 	case AGPIOC_INFO:
843 		return agp_info_user(dev, (agp_info *) data);
844 
845 	case AGPIOC_ACQUIRE:
846 		return agp_acquire_helper(dev, AGP_ACQUIRE_USER);
847 
848 	case AGPIOC_RELEASE:
849 		return agp_release_helper(dev, AGP_ACQUIRE_USER);
850 
851 	case AGPIOC_SETUP:
852 		return agp_setup_user(dev, (agp_setup *)data);
853 
854 	case AGPIOC_ALLOCATE:
855 		return agp_allocate_user(dev, (agp_allocate *)data);
856 
857 	case AGPIOC_DEALLOCATE:
858 		return agp_deallocate_user(dev, *(int *) data);
859 
860 	case AGPIOC_BIND:
861 		return agp_bind_user(dev, (agp_bind *)data);
862 
863 	case AGPIOC_UNBIND:
864 		return agp_unbind_user(dev, (agp_unbind *)data);
865 
866 	case AGPIOC_CHIPSET_FLUSH:
867 		return agp_chipset_flush(dev);
868 	}
869 
870 	return EINVAL;
871 }
872 
873 static int
874 agp_mmap(struct cdev *kdev, vm_ooffset_t offset, vm_paddr_t *paddr,
875     int prot, vm_memattr_t *memattr)
876 {
877 	device_t dev = kdev->si_drv1;
878 	struct agp_softc *sc = device_get_softc(dev);
879 
880 	if (offset > AGP_GET_APERTURE(dev))
881 		return -1;
882 	if (sc->as_aperture == NULL)
883 		return -1;
884 	*paddr = rman_get_start(sc->as_aperture) + offset;
885 	return 0;
886 }
887 
888 /* Implementation of the kernel api */
889 
890 device_t
891 agp_find_device()
892 {
893 	device_t *children, child;
894 	int i, count;
895 
896 	if (!agp_devclass)
897 		return NULL;
898 	if (devclass_get_devices(agp_devclass, &children, &count) != 0)
899 		return NULL;
900 	child = NULL;
901 	for (i = 0; i < count; i++) {
902 		if (device_is_attached(children[i])) {
903 			child = children[i];
904 			break;
905 		}
906 	}
907 	free(children, M_TEMP);
908 	return child;
909 }
910 
911 enum agp_acquire_state
912 agp_state(device_t dev)
913 {
914 	struct agp_softc *sc = device_get_softc(dev);
915 	return sc->as_state;
916 }
917 
918 void
919 agp_get_info(device_t dev, struct agp_info *info)
920 {
921 	struct agp_softc *sc = device_get_softc(dev);
922 
923 	info->ai_mode =
924 		pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
925 	if (sc->as_aperture != NULL)
926 		info->ai_aperture_base = rman_get_start(sc->as_aperture);
927 	else
928 		info->ai_aperture_base = 0;
929 	info->ai_aperture_size = AGP_GET_APERTURE(dev);
930 	info->ai_memory_allowed = sc->as_maxmem;
931 	info->ai_memory_used = sc->as_allocated;
932 }
933 
934 int
935 agp_acquire(device_t dev)
936 {
937 	return agp_acquire_helper(dev, AGP_ACQUIRE_KERNEL);
938 }
939 
940 int
941 agp_release(device_t dev)
942 {
943 	return agp_release_helper(dev, AGP_ACQUIRE_KERNEL);
944 }
945 
946 int
947 agp_enable(device_t dev, u_int32_t mode)
948 {
949 	return AGP_ENABLE(dev, mode);
950 }
951 
952 void *agp_alloc_memory(device_t dev, int type, vm_size_t bytes)
953 {
954 	return  (void *) AGP_ALLOC_MEMORY(dev, type, bytes);
955 }
956 
957 void agp_free_memory(device_t dev, void *handle)
958 {
959 	struct agp_memory *mem = (struct agp_memory *) handle;
960 	AGP_FREE_MEMORY(dev, mem);
961 }
962 
963 int agp_bind_memory(device_t dev, void *handle, vm_offset_t offset)
964 {
965 	struct agp_memory *mem = (struct agp_memory *) handle;
966 	return AGP_BIND_MEMORY(dev, mem, offset);
967 }
968 
969 int agp_unbind_memory(device_t dev, void *handle)
970 {
971 	struct agp_memory *mem = (struct agp_memory *) handle;
972 	return AGP_UNBIND_MEMORY(dev, mem);
973 }
974 
975 void agp_memory_info(device_t dev, void *handle, struct
976 		     agp_memory_info *mi)
977 {
978 	struct agp_memory *mem = (struct agp_memory *) handle;
979 
980 	mi->ami_size = mem->am_size;
981 	mi->ami_physical = mem->am_physical;
982 	mi->ami_offset = mem->am_offset;
983 	mi->ami_is_bound = mem->am_is_bound;
984 }
985 
986 int
987 agp_bind_pages(device_t dev, vm_page_t *pages, vm_size_t size,
988     vm_offset_t offset)
989 {
990 	struct agp_softc *sc;
991 	vm_offset_t i, j, k, pa;
992 	vm_page_t m;
993 	int error;
994 
995 	if ((size & (AGP_PAGE_SIZE - 1)) != 0 ||
996 	    (offset & (AGP_PAGE_SIZE - 1)) != 0)
997 		return (EINVAL);
998 
999 	sc = device_get_softc(dev);
1000 
1001 	mtx_lock(&sc->as_lock);
1002 	for (i = 0; i < size; i += PAGE_SIZE) {
1003 		m = pages[OFF_TO_IDX(i)];
1004 		KASSERT(m->wire_count > 0,
1005 		    ("agp_bind_pages: page %p hasn't been wired", m));
1006 
1007 		/*
1008 		 * Install entries in the GATT, making sure that if
1009 		 * AGP_PAGE_SIZE < PAGE_SIZE and size is not
1010 		 * aligned to PAGE_SIZE, we don't modify too many GATT
1011 		 * entries.
1012 		 */
1013 		for (j = 0; j < PAGE_SIZE && i + j < size; j += AGP_PAGE_SIZE) {
1014 			pa = VM_PAGE_TO_PHYS(m) + j;
1015 			AGP_DPF("binding offset %#jx to pa %#jx\n",
1016 				(uintmax_t)offset + i + j, (uintmax_t)pa);
1017 			error = AGP_BIND_PAGE(dev, offset + i + j, pa);
1018 			if (error) {
1019 				/*
1020 				 * Bail out. Reverse all the mappings.
1021 				 */
1022 				for (k = 0; k < i + j; k += AGP_PAGE_SIZE)
1023 					AGP_UNBIND_PAGE(dev, offset + k);
1024 
1025 				mtx_unlock(&sc->as_lock);
1026 				return (error);
1027 			}
1028 		}
1029 	}
1030 
1031 	AGP_FLUSH_TLB(dev);
1032 
1033 	mtx_unlock(&sc->as_lock);
1034 	return (0);
1035 }
1036 
1037 int
1038 agp_unbind_pages(device_t dev, vm_size_t size, vm_offset_t offset)
1039 {
1040 	struct agp_softc *sc;
1041 	vm_offset_t i;
1042 
1043 	if ((size & (AGP_PAGE_SIZE - 1)) != 0 ||
1044 	    (offset & (AGP_PAGE_SIZE - 1)) != 0)
1045 		return (EINVAL);
1046 
1047 	sc = device_get_softc(dev);
1048 
1049 	mtx_lock(&sc->as_lock);
1050 	for (i = 0; i < size; i += AGP_PAGE_SIZE)
1051 		AGP_UNBIND_PAGE(dev, offset + i);
1052 
1053 	AGP_FLUSH_TLB(dev);
1054 
1055 	mtx_unlock(&sc->as_lock);
1056 	return (0);
1057 }
1058