xref: /freebsd/sys/dev/agp/agp.c (revision cab6a39d7b343596a5823e65c0f7b426551ec22d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2000 Doug Rabson
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include "opt_agp.h"
33 
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/malloc.h>
37 #include <sys/kernel.h>
38 #include <sys/module.h>
39 #include <sys/bus.h>
40 #include <sys/conf.h>
41 #include <sys/ioccom.h>
42 #include <sys/agpio.h>
43 #include <sys/lock.h>
44 #include <sys/mutex.h>
45 #include <sys/proc.h>
46 #include <sys/rwlock.h>
47 
48 #include <dev/agp/agppriv.h>
49 #include <dev/agp/agpvar.h>
50 #include <dev/agp/agpreg.h>
51 #include <dev/pci/pcivar.h>
52 #include <dev/pci/pcireg.h>
53 
54 #include <vm/vm.h>
55 #include <vm/vm_extern.h>
56 #include <vm/vm_kern.h>
57 #include <vm/vm_param.h>
58 #include <vm/vm_object.h>
59 #include <vm/vm_page.h>
60 #include <vm/vm_pageout.h>
61 #include <vm/pmap.h>
62 
63 #include <machine/bus.h>
64 #include <machine/resource.h>
65 #include <sys/rman.h>
66 
67 MODULE_VERSION(agp, 1);
68 
69 MALLOC_DEFINE(M_AGP, "agp", "AGP data structures");
70 
71 				/* agp_drv.c */
72 static d_open_t agp_open;
73 static d_close_t agp_close;
74 static d_ioctl_t agp_ioctl;
75 static d_mmap_t agp_mmap;
76 
77 static struct cdevsw agp_cdevsw = {
78 	.d_version =	D_VERSION,
79 	.d_flags =	D_NEEDGIANT,
80 	.d_open =	agp_open,
81 	.d_close =	agp_close,
82 	.d_ioctl =	agp_ioctl,
83 	.d_mmap =	agp_mmap,
84 	.d_name =	"agp",
85 };
86 
87 static devclass_t agp_devclass;
88 
89 /* Helper functions for implementing chipset mini drivers. */
90 
91 u_int8_t
92 agp_find_caps(device_t dev)
93 {
94 	int capreg;
95 
96 	if (pci_find_cap(dev, PCIY_AGP, &capreg) != 0)
97 		capreg = 0;
98 	return (capreg);
99 }
100 
101 /*
102  * Find an AGP display device (if any).
103  */
104 static device_t
105 agp_find_display(void)
106 {
107 	devclass_t pci = devclass_find("pci");
108 	device_t bus, dev = 0;
109 	device_t *kids;
110 	int busnum, numkids, i;
111 
112 	for (busnum = 0; busnum < devclass_get_maxunit(pci); busnum++) {
113 		bus = devclass_get_device(pci, busnum);
114 		if (!bus)
115 			continue;
116 		if (device_get_children(bus, &kids, &numkids) != 0)
117 			continue;
118 		for (i = 0; i < numkids; i++) {
119 			dev = kids[i];
120 			if (pci_get_class(dev) == PCIC_DISPLAY
121 			    && pci_get_subclass(dev) == PCIS_DISPLAY_VGA)
122 				if (agp_find_caps(dev)) {
123 					free(kids, M_TEMP);
124 					return dev;
125 				}
126 
127 		}
128 		free(kids, M_TEMP);
129 	}
130 
131 	return 0;
132 }
133 
134 struct agp_gatt *
135 agp_alloc_gatt(device_t dev)
136 {
137 	u_int32_t apsize = AGP_GET_APERTURE(dev);
138 	u_int32_t entries = apsize >> AGP_PAGE_SHIFT;
139 	struct agp_gatt *gatt;
140 
141 	if (bootverbose)
142 		device_printf(dev,
143 			      "allocating GATT for aperture of size %dM\n",
144 			      apsize / (1024*1024));
145 
146 	if (entries == 0) {
147 		device_printf(dev, "bad aperture size\n");
148 		return NULL;
149 	}
150 
151 	gatt = malloc(sizeof(struct agp_gatt), M_AGP, M_NOWAIT);
152 	if (!gatt)
153 		return 0;
154 
155 	gatt->ag_entries = entries;
156 	gatt->ag_virtual = (void *)kmem_alloc_contig(entries *
157 	    sizeof(u_int32_t), M_NOWAIT | M_ZERO, 0, ~0, PAGE_SIZE, 0,
158 	    VM_MEMATTR_WRITE_COMBINING);
159 	if (!gatt->ag_virtual) {
160 		if (bootverbose)
161 			device_printf(dev, "contiguous allocation failed\n");
162 		free(gatt, M_AGP);
163 		return 0;
164 	}
165 	gatt->ag_physical = vtophys((vm_offset_t) gatt->ag_virtual);
166 
167 	return gatt;
168 }
169 
170 void
171 agp_free_gatt(struct agp_gatt *gatt)
172 {
173 	kmem_free((vm_offset_t)gatt->ag_virtual, gatt->ag_entries *
174 	    sizeof(u_int32_t));
175 	free(gatt, M_AGP);
176 }
177 
178 static u_int agp_max[][2] = {
179 	{0,	0},
180 	{32,	4},
181 	{64,	28},
182 	{128,	96},
183 	{256,	204},
184 	{512,	440},
185 	{1024,	942},
186 	{2048,	1920},
187 	{4096,	3932}
188 };
189 #define	AGP_MAX_SIZE	nitems(agp_max)
190 
191 /**
192  * Sets the PCI resource which represents the AGP aperture.
193  *
194  * If not called, the default AGP aperture resource of AGP_APBASE will
195  * be used.  Must be called before agp_generic_attach().
196  */
197 void
198 agp_set_aperture_resource(device_t dev, int rid)
199 {
200 	struct agp_softc *sc = device_get_softc(dev);
201 
202 	sc->as_aperture_rid = rid;
203 }
204 
205 int
206 agp_generic_attach(device_t dev)
207 {
208 	struct agp_softc *sc = device_get_softc(dev);
209 	int i;
210 	u_int memsize;
211 
212 	/*
213 	 * Find and map the aperture, RF_SHAREABLE for DRM but not RF_ACTIVE
214 	 * because the kernel doesn't need to map it.
215 	 */
216 
217 	if (sc->as_aperture_rid != -1) {
218 		if (sc->as_aperture_rid == 0)
219 			sc->as_aperture_rid = AGP_APBASE;
220 
221 		sc->as_aperture = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
222 		    &sc->as_aperture_rid, RF_SHAREABLE);
223 		if (!sc->as_aperture)
224 			return ENOMEM;
225 	}
226 
227 	/*
228 	 * Work out an upper bound for agp memory allocation. This
229 	 * uses a heurisitc table from the Linux driver.
230 	 */
231 	memsize = ptoa(realmem) >> 20;
232 	for (i = 0; i < AGP_MAX_SIZE; i++) {
233 		if (memsize <= agp_max[i][0])
234 			break;
235 	}
236 	if (i == AGP_MAX_SIZE)
237 		i = AGP_MAX_SIZE - 1;
238 	sc->as_maxmem = agp_max[i][1] << 20U;
239 
240 	/*
241 	 * The lock is used to prevent re-entry to
242 	 * agp_generic_bind_memory() since that function can sleep.
243 	 */
244 	mtx_init(&sc->as_lock, "agp lock", NULL, MTX_DEF);
245 
246 	/*
247 	 * Initialise stuff for the userland device.
248 	 */
249 	agp_devclass = devclass_find("agp");
250 	TAILQ_INIT(&sc->as_memory);
251 	sc->as_nextid = 1;
252 
253 	sc->as_devnode = make_dev(&agp_cdevsw,
254 	    0, UID_ROOT, GID_WHEEL, 0600, "agpgart");
255 	sc->as_devnode->si_drv1 = dev;
256 
257 	return 0;
258 }
259 
260 void
261 agp_free_cdev(device_t dev)
262 {
263 	struct agp_softc *sc = device_get_softc(dev);
264 
265 	destroy_dev(sc->as_devnode);
266 }
267 
268 void
269 agp_free_res(device_t dev)
270 {
271 	struct agp_softc *sc = device_get_softc(dev);
272 
273 	if (sc->as_aperture != NULL)
274 		bus_release_resource(dev, SYS_RES_MEMORY, sc->as_aperture_rid,
275 		    sc->as_aperture);
276 	mtx_destroy(&sc->as_lock);
277 }
278 
279 int
280 agp_generic_detach(device_t dev)
281 {
282 
283 	agp_free_cdev(dev);
284 	agp_free_res(dev);
285 	return 0;
286 }
287 
288 /**
289  * Default AGP aperture size detection which simply returns the size of
290  * the aperture's PCI resource.
291  */
292 u_int32_t
293 agp_generic_get_aperture(device_t dev)
294 {
295 	struct agp_softc *sc = device_get_softc(dev);
296 
297 	return rman_get_size(sc->as_aperture);
298 }
299 
300 /**
301  * Default AGP aperture size setting function, which simply doesn't allow
302  * changes to resource size.
303  */
304 int
305 agp_generic_set_aperture(device_t dev, u_int32_t aperture)
306 {
307 	u_int32_t current_aperture;
308 
309 	current_aperture = AGP_GET_APERTURE(dev);
310 	if (current_aperture != aperture)
311 		return EINVAL;
312 	else
313 		return 0;
314 }
315 
316 /*
317  * This does the enable logic for v3, with the same topology
318  * restrictions as in place for v2 -- one bus, one device on the bus.
319  */
320 static int
321 agp_v3_enable(device_t dev, device_t mdev, u_int32_t mode)
322 {
323 	u_int32_t tstatus, mstatus;
324 	u_int32_t command;
325 	int rq, sba, fw, rate, arqsz, cal;
326 
327 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
328 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
329 
330 	/* Set RQ to the min of mode, tstatus and mstatus */
331 	rq = AGP_MODE_GET_RQ(mode);
332 	if (AGP_MODE_GET_RQ(tstatus) < rq)
333 		rq = AGP_MODE_GET_RQ(tstatus);
334 	if (AGP_MODE_GET_RQ(mstatus) < rq)
335 		rq = AGP_MODE_GET_RQ(mstatus);
336 
337 	/*
338 	 * ARQSZ - Set the value to the maximum one.
339 	 * Don't allow the mode register to override values.
340 	 */
341 	arqsz = AGP_MODE_GET_ARQSZ(mode);
342 	if (AGP_MODE_GET_ARQSZ(tstatus) > rq)
343 		rq = AGP_MODE_GET_ARQSZ(tstatus);
344 	if (AGP_MODE_GET_ARQSZ(mstatus) > rq)
345 		rq = AGP_MODE_GET_ARQSZ(mstatus);
346 
347 	/* Calibration cycle - don't allow override by mode register */
348 	cal = AGP_MODE_GET_CAL(tstatus);
349 	if (AGP_MODE_GET_CAL(mstatus) < cal)
350 		cal = AGP_MODE_GET_CAL(mstatus);
351 
352 	/* SBA must be supported for AGP v3. */
353 	sba = 1;
354 
355 	/* Set FW if all three support it. */
356 	fw = (AGP_MODE_GET_FW(tstatus)
357 	       & AGP_MODE_GET_FW(mstatus)
358 	       & AGP_MODE_GET_FW(mode));
359 
360 	/* Figure out the max rate */
361 	rate = (AGP_MODE_GET_RATE(tstatus)
362 		& AGP_MODE_GET_RATE(mstatus)
363 		& AGP_MODE_GET_RATE(mode));
364 	if (rate & AGP_MODE_V3_RATE_8x)
365 		rate = AGP_MODE_V3_RATE_8x;
366 	else
367 		rate = AGP_MODE_V3_RATE_4x;
368 	if (bootverbose)
369 		device_printf(dev, "Setting AGP v3 mode %d\n", rate * 4);
370 
371 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, 0, 4);
372 
373 	/* Construct the new mode word and tell the hardware */
374 	command = 0;
375 	command = AGP_MODE_SET_RQ(0, rq);
376 	command = AGP_MODE_SET_ARQSZ(command, arqsz);
377 	command = AGP_MODE_SET_CAL(command, cal);
378 	command = AGP_MODE_SET_SBA(command, sba);
379 	command = AGP_MODE_SET_FW(command, fw);
380 	command = AGP_MODE_SET_RATE(command, rate);
381 	command = AGP_MODE_SET_MODE_3(command, 1);
382 	command = AGP_MODE_SET_AGP(command, 1);
383 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
384 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
385 
386 	return 0;
387 }
388 
389 static int
390 agp_v2_enable(device_t dev, device_t mdev, u_int32_t mode)
391 {
392 	u_int32_t tstatus, mstatus;
393 	u_int32_t command;
394 	int rq, sba, fw, rate;
395 
396 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
397 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
398 
399 	/* Set RQ to the min of mode, tstatus and mstatus */
400 	rq = AGP_MODE_GET_RQ(mode);
401 	if (AGP_MODE_GET_RQ(tstatus) < rq)
402 		rq = AGP_MODE_GET_RQ(tstatus);
403 	if (AGP_MODE_GET_RQ(mstatus) < rq)
404 		rq = AGP_MODE_GET_RQ(mstatus);
405 
406 	/* Set SBA if all three can deal with SBA */
407 	sba = (AGP_MODE_GET_SBA(tstatus)
408 	       & AGP_MODE_GET_SBA(mstatus)
409 	       & AGP_MODE_GET_SBA(mode));
410 
411 	/* Similar for FW */
412 	fw = (AGP_MODE_GET_FW(tstatus)
413 	       & AGP_MODE_GET_FW(mstatus)
414 	       & AGP_MODE_GET_FW(mode));
415 
416 	/* Figure out the max rate */
417 	rate = (AGP_MODE_GET_RATE(tstatus)
418 		& AGP_MODE_GET_RATE(mstatus)
419 		& AGP_MODE_GET_RATE(mode));
420 	if (rate & AGP_MODE_V2_RATE_4x)
421 		rate = AGP_MODE_V2_RATE_4x;
422 	else if (rate & AGP_MODE_V2_RATE_2x)
423 		rate = AGP_MODE_V2_RATE_2x;
424 	else
425 		rate = AGP_MODE_V2_RATE_1x;
426 	if (bootverbose)
427 		device_printf(dev, "Setting AGP v2 mode %d\n", rate);
428 
429 	/* Construct the new mode word and tell the hardware */
430 	command = 0;
431 	command = AGP_MODE_SET_RQ(0, rq);
432 	command = AGP_MODE_SET_SBA(command, sba);
433 	command = AGP_MODE_SET_FW(command, fw);
434 	command = AGP_MODE_SET_RATE(command, rate);
435 	command = AGP_MODE_SET_AGP(command, 1);
436 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
437 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
438 
439 	return 0;
440 }
441 
442 int
443 agp_generic_enable(device_t dev, u_int32_t mode)
444 {
445 	device_t mdev = agp_find_display();
446 	u_int32_t tstatus, mstatus;
447 
448 	if (!mdev) {
449 		AGP_DPF("can't find display\n");
450 		return ENXIO;
451 	}
452 
453 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
454 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
455 
456 	/*
457 	 * Check display and bridge for AGP v3 support.  AGP v3 allows
458 	 * more variety in topology than v2, e.g. multiple AGP devices
459 	 * attached to one bridge, or multiple AGP bridges in one
460 	 * system.  This doesn't attempt to address those situations,
461 	 * but should work fine for a classic single AGP slot system
462 	 * with AGP v3.
463 	 */
464 	if (AGP_MODE_GET_MODE_3(mode) &&
465 	    AGP_MODE_GET_MODE_3(tstatus) &&
466 	    AGP_MODE_GET_MODE_3(mstatus))
467 		return (agp_v3_enable(dev, mdev, mode));
468 	else
469 		return (agp_v2_enable(dev, mdev, mode));
470 }
471 
472 struct agp_memory *
473 agp_generic_alloc_memory(device_t dev, int type, vm_size_t size)
474 {
475 	struct agp_softc *sc = device_get_softc(dev);
476 	struct agp_memory *mem;
477 
478 	if ((size & (AGP_PAGE_SIZE - 1)) != 0)
479 		return 0;
480 
481 	if (size > sc->as_maxmem - sc->as_allocated)
482 		return 0;
483 
484 	if (type != 0) {
485 		printf("agp_generic_alloc_memory: unsupported type %d\n",
486 		       type);
487 		return 0;
488 	}
489 
490 	mem = malloc(sizeof *mem, M_AGP, M_WAITOK);
491 	mem->am_id = sc->as_nextid++;
492 	mem->am_size = size;
493 	mem->am_type = 0;
494 	mem->am_obj = vm_object_allocate(OBJT_DEFAULT, atop(round_page(size)));
495 	mem->am_physical = 0;
496 	mem->am_offset = 0;
497 	mem->am_is_bound = 0;
498 	TAILQ_INSERT_TAIL(&sc->as_memory, mem, am_link);
499 	sc->as_allocated += size;
500 
501 	return mem;
502 }
503 
504 int
505 agp_generic_free_memory(device_t dev, struct agp_memory *mem)
506 {
507 	struct agp_softc *sc = device_get_softc(dev);
508 
509 	if (mem->am_is_bound)
510 		return EBUSY;
511 
512 	sc->as_allocated -= mem->am_size;
513 	TAILQ_REMOVE(&sc->as_memory, mem, am_link);
514 	vm_object_deallocate(mem->am_obj);
515 	free(mem, M_AGP);
516 	return 0;
517 }
518 
519 int
520 agp_generic_bind_memory(device_t dev, struct agp_memory *mem,
521 			vm_offset_t offset)
522 {
523 	struct agp_softc *sc = device_get_softc(dev);
524 	vm_offset_t i, j, k;
525 	vm_page_t m;
526 	int error;
527 
528 	/* Do some sanity checks first. */
529 	if ((offset & (AGP_PAGE_SIZE - 1)) != 0 ||
530 	    offset + mem->am_size > AGP_GET_APERTURE(dev)) {
531 		device_printf(dev, "binding memory at bad offset %#x\n",
532 		    (int)offset);
533 		return EINVAL;
534 	}
535 
536 	/*
537 	 * Allocate the pages early, before acquiring the lock,
538 	 * because vm_page_grab() may sleep and we can't hold a mutex
539 	 * while sleeping.
540 	 */
541 	VM_OBJECT_WLOCK(mem->am_obj);
542 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
543 		/*
544 		 * Find a page from the object and wire it
545 		 * down. This page will be mapped using one or more
546 		 * entries in the GATT (assuming that PAGE_SIZE >=
547 		 * AGP_PAGE_SIZE. If this is the first call to bind,
548 		 * the pages will be allocated and zeroed.
549 		 */
550 		m = vm_page_grab(mem->am_obj, OFF_TO_IDX(i),
551 		    VM_ALLOC_WIRED | VM_ALLOC_ZERO);
552 		AGP_DPF("found page pa=%#jx\n", (uintmax_t)VM_PAGE_TO_PHYS(m));
553 	}
554 	VM_OBJECT_WUNLOCK(mem->am_obj);
555 
556 	mtx_lock(&sc->as_lock);
557 
558 	if (mem->am_is_bound) {
559 		device_printf(dev, "memory already bound\n");
560 		error = EINVAL;
561 		VM_OBJECT_WLOCK(mem->am_obj);
562 		i = 0;
563 		goto bad;
564 	}
565 
566 	/*
567 	 * Bind the individual pages and flush the chipset's
568 	 * TLB.
569 	 */
570 	VM_OBJECT_WLOCK(mem->am_obj);
571 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
572 		m = vm_page_lookup(mem->am_obj, OFF_TO_IDX(i));
573 
574 		/*
575 		 * Install entries in the GATT, making sure that if
576 		 * AGP_PAGE_SIZE < PAGE_SIZE and mem->am_size is not
577 		 * aligned to PAGE_SIZE, we don't modify too many GATT
578 		 * entries.
579 		 */
580 		for (j = 0; j < PAGE_SIZE && i + j < mem->am_size;
581 		     j += AGP_PAGE_SIZE) {
582 			vm_offset_t pa = VM_PAGE_TO_PHYS(m) + j;
583 			AGP_DPF("binding offset %#jx to pa %#jx\n",
584 				(uintmax_t)offset + i + j, (uintmax_t)pa);
585 			error = AGP_BIND_PAGE(dev, offset + i + j, pa);
586 			if (error) {
587 				/*
588 				 * Bail out. Reverse all the mappings
589 				 * and unwire the pages.
590 				 */
591 				for (k = 0; k < i + j; k += AGP_PAGE_SIZE)
592 					AGP_UNBIND_PAGE(dev, offset + k);
593 				goto bad;
594 			}
595 		}
596 		vm_page_xunbusy(m);
597 	}
598 	VM_OBJECT_WUNLOCK(mem->am_obj);
599 
600 	/*
601 	 * Make sure the chipset gets the new mappings.
602 	 */
603 	AGP_FLUSH_TLB(dev);
604 
605 	mem->am_offset = offset;
606 	mem->am_is_bound = 1;
607 
608 	mtx_unlock(&sc->as_lock);
609 
610 	return 0;
611 bad:
612 	mtx_unlock(&sc->as_lock);
613 	VM_OBJECT_ASSERT_WLOCKED(mem->am_obj);
614 	for (k = 0; k < mem->am_size; k += PAGE_SIZE) {
615 		m = vm_page_lookup(mem->am_obj, OFF_TO_IDX(k));
616 		if (k >= i)
617 			vm_page_xunbusy(m);
618 		vm_page_unwire(m, PQ_INACTIVE);
619 	}
620 	VM_OBJECT_WUNLOCK(mem->am_obj);
621 
622 	return error;
623 }
624 
625 int
626 agp_generic_unbind_memory(device_t dev, struct agp_memory *mem)
627 {
628 	struct agp_softc *sc = device_get_softc(dev);
629 	vm_page_t m;
630 	int i;
631 
632 	mtx_lock(&sc->as_lock);
633 
634 	if (!mem->am_is_bound) {
635 		device_printf(dev, "memory is not bound\n");
636 		mtx_unlock(&sc->as_lock);
637 		return EINVAL;
638 	}
639 
640 	/*
641 	 * Unbind the individual pages and flush the chipset's
642 	 * TLB. Unwire the pages so they can be swapped.
643 	 */
644 	for (i = 0; i < mem->am_size; i += AGP_PAGE_SIZE)
645 		AGP_UNBIND_PAGE(dev, mem->am_offset + i);
646 
647 	AGP_FLUSH_TLB(dev);
648 
649 	VM_OBJECT_WLOCK(mem->am_obj);
650 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
651 		m = vm_page_lookup(mem->am_obj, atop(i));
652 		vm_page_unwire(m, PQ_INACTIVE);
653 	}
654 	VM_OBJECT_WUNLOCK(mem->am_obj);
655 
656 	mem->am_offset = 0;
657 	mem->am_is_bound = 0;
658 
659 	mtx_unlock(&sc->as_lock);
660 
661 	return 0;
662 }
663 
664 /* Helper functions for implementing user/kernel api */
665 
666 static int
667 agp_acquire_helper(device_t dev, enum agp_acquire_state state)
668 {
669 	struct agp_softc *sc = device_get_softc(dev);
670 
671 	if (sc->as_state != AGP_ACQUIRE_FREE)
672 		return EBUSY;
673 	sc->as_state = state;
674 
675 	return 0;
676 }
677 
678 static int
679 agp_release_helper(device_t dev, enum agp_acquire_state state)
680 {
681 	struct agp_softc *sc = device_get_softc(dev);
682 
683 	if (sc->as_state == AGP_ACQUIRE_FREE)
684 		return 0;
685 
686 	if (sc->as_state != state)
687 		return EBUSY;
688 
689 	sc->as_state = AGP_ACQUIRE_FREE;
690 	return 0;
691 }
692 
693 static struct agp_memory *
694 agp_find_memory(device_t dev, int id)
695 {
696 	struct agp_softc *sc = device_get_softc(dev);
697 	struct agp_memory *mem;
698 
699 	AGP_DPF("searching for memory block %d\n", id);
700 	TAILQ_FOREACH(mem, &sc->as_memory, am_link) {
701 		AGP_DPF("considering memory block %d\n", mem->am_id);
702 		if (mem->am_id == id)
703 			return mem;
704 	}
705 	return 0;
706 }
707 
708 /* Implementation of the userland ioctl api */
709 
710 static int
711 agp_info_user(device_t dev, agp_info *info)
712 {
713 	struct agp_softc *sc = device_get_softc(dev);
714 
715 	bzero(info, sizeof *info);
716 	info->bridge_id = pci_get_devid(dev);
717 	info->agp_mode =
718 	    pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
719 	if (sc->as_aperture)
720 		info->aper_base = rman_get_start(sc->as_aperture);
721 	else
722 		info->aper_base = 0;
723 	info->aper_size = AGP_GET_APERTURE(dev) >> 20;
724 	info->pg_total = info->pg_system = sc->as_maxmem >> AGP_PAGE_SHIFT;
725 	info->pg_used = sc->as_allocated >> AGP_PAGE_SHIFT;
726 
727 	return 0;
728 }
729 
730 static int
731 agp_setup_user(device_t dev, agp_setup *setup)
732 {
733 	return AGP_ENABLE(dev, setup->agp_mode);
734 }
735 
736 static int
737 agp_allocate_user(device_t dev, agp_allocate *alloc)
738 {
739 	struct agp_memory *mem;
740 
741 	mem = AGP_ALLOC_MEMORY(dev,
742 			       alloc->type,
743 			       alloc->pg_count << AGP_PAGE_SHIFT);
744 	if (mem) {
745 		alloc->key = mem->am_id;
746 		alloc->physical = mem->am_physical;
747 		return 0;
748 	} else {
749 		return ENOMEM;
750 	}
751 }
752 
753 static int
754 agp_deallocate_user(device_t dev, int id)
755 {
756 	struct agp_memory *mem = agp_find_memory(dev, id);
757 
758 	if (mem) {
759 		AGP_FREE_MEMORY(dev, mem);
760 		return 0;
761 	} else {
762 		return ENOENT;
763 	}
764 }
765 
766 static int
767 agp_bind_user(device_t dev, agp_bind *bind)
768 {
769 	struct agp_memory *mem = agp_find_memory(dev, bind->key);
770 
771 	if (!mem)
772 		return ENOENT;
773 
774 	return AGP_BIND_MEMORY(dev, mem, bind->pg_start << AGP_PAGE_SHIFT);
775 }
776 
777 static int
778 agp_unbind_user(device_t dev, agp_unbind *unbind)
779 {
780 	struct agp_memory *mem = agp_find_memory(dev, unbind->key);
781 
782 	if (!mem)
783 		return ENOENT;
784 
785 	return AGP_UNBIND_MEMORY(dev, mem);
786 }
787 
788 static int
789 agp_chipset_flush(device_t dev)
790 {
791 
792 	return (AGP_CHIPSET_FLUSH(dev));
793 }
794 
795 static int
796 agp_open(struct cdev *kdev, int oflags, int devtype, struct thread *td)
797 {
798 	device_t dev = kdev->si_drv1;
799 	struct agp_softc *sc = device_get_softc(dev);
800 
801 	if (!sc->as_isopen) {
802 		sc->as_isopen = 1;
803 		device_busy(dev);
804 	}
805 
806 	return 0;
807 }
808 
809 static int
810 agp_close(struct cdev *kdev, int fflag, int devtype, struct thread *td)
811 {
812 	device_t dev = kdev->si_drv1;
813 	struct agp_softc *sc = device_get_softc(dev);
814 	struct agp_memory *mem;
815 
816 	/*
817 	 * Clear the GATT and force release on last close
818 	 */
819 	while ((mem = TAILQ_FIRST(&sc->as_memory)) != NULL) {
820 		if (mem->am_is_bound)
821 			AGP_UNBIND_MEMORY(dev, mem);
822 		AGP_FREE_MEMORY(dev, mem);
823 	}
824 	if (sc->as_state == AGP_ACQUIRE_USER)
825 		agp_release_helper(dev, AGP_ACQUIRE_USER);
826 	sc->as_isopen = 0;
827 	device_unbusy(dev);
828 
829 	return 0;
830 }
831 
832 static int
833 agp_ioctl(struct cdev *kdev, u_long cmd, caddr_t data, int fflag, struct thread *td)
834 {
835 	device_t dev = kdev->si_drv1;
836 
837 	switch (cmd) {
838 	case AGPIOC_INFO:
839 		return agp_info_user(dev, (agp_info *) data);
840 
841 	case AGPIOC_ACQUIRE:
842 		return agp_acquire_helper(dev, AGP_ACQUIRE_USER);
843 
844 	case AGPIOC_RELEASE:
845 		return agp_release_helper(dev, AGP_ACQUIRE_USER);
846 
847 	case AGPIOC_SETUP:
848 		return agp_setup_user(dev, (agp_setup *)data);
849 
850 	case AGPIOC_ALLOCATE:
851 		return agp_allocate_user(dev, (agp_allocate *)data);
852 
853 	case AGPIOC_DEALLOCATE:
854 		return agp_deallocate_user(dev, *(int *) data);
855 
856 	case AGPIOC_BIND:
857 		return agp_bind_user(dev, (agp_bind *)data);
858 
859 	case AGPIOC_UNBIND:
860 		return agp_unbind_user(dev, (agp_unbind *)data);
861 
862 	case AGPIOC_CHIPSET_FLUSH:
863 		return agp_chipset_flush(dev);
864 	}
865 
866 	return EINVAL;
867 }
868 
869 static int
870 agp_mmap(struct cdev *kdev, vm_ooffset_t offset, vm_paddr_t *paddr,
871     int prot, vm_memattr_t *memattr)
872 {
873 	device_t dev = kdev->si_drv1;
874 	struct agp_softc *sc = device_get_softc(dev);
875 
876 	if (offset > AGP_GET_APERTURE(dev))
877 		return -1;
878 	if (sc->as_aperture == NULL)
879 		return -1;
880 	*paddr = rman_get_start(sc->as_aperture) + offset;
881 	return 0;
882 }
883 
884 /* Implementation of the kernel api */
885 
886 device_t
887 agp_find_device()
888 {
889 	device_t *children, child;
890 	int i, count;
891 
892 	if (!agp_devclass)
893 		return NULL;
894 	if (devclass_get_devices(agp_devclass, &children, &count) != 0)
895 		return NULL;
896 	child = NULL;
897 	for (i = 0; i < count; i++) {
898 		if (device_is_attached(children[i])) {
899 			child = children[i];
900 			break;
901 		}
902 	}
903 	free(children, M_TEMP);
904 	return child;
905 }
906 
907 enum agp_acquire_state
908 agp_state(device_t dev)
909 {
910 	struct agp_softc *sc = device_get_softc(dev);
911 	return sc->as_state;
912 }
913 
914 void
915 agp_get_info(device_t dev, struct agp_info *info)
916 {
917 	struct agp_softc *sc = device_get_softc(dev);
918 
919 	info->ai_mode =
920 		pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
921 	if (sc->as_aperture != NULL)
922 		info->ai_aperture_base = rman_get_start(sc->as_aperture);
923 	else
924 		info->ai_aperture_base = 0;
925 	info->ai_aperture_size = AGP_GET_APERTURE(dev);
926 	info->ai_memory_allowed = sc->as_maxmem;
927 	info->ai_memory_used = sc->as_allocated;
928 }
929 
930 int
931 agp_acquire(device_t dev)
932 {
933 	return agp_acquire_helper(dev, AGP_ACQUIRE_KERNEL);
934 }
935 
936 int
937 agp_release(device_t dev)
938 {
939 	return agp_release_helper(dev, AGP_ACQUIRE_KERNEL);
940 }
941 
942 int
943 agp_enable(device_t dev, u_int32_t mode)
944 {
945 	return AGP_ENABLE(dev, mode);
946 }
947 
948 void *agp_alloc_memory(device_t dev, int type, vm_size_t bytes)
949 {
950 	return  (void *) AGP_ALLOC_MEMORY(dev, type, bytes);
951 }
952 
953 void agp_free_memory(device_t dev, void *handle)
954 {
955 	struct agp_memory *mem = (struct agp_memory *) handle;
956 	AGP_FREE_MEMORY(dev, mem);
957 }
958 
959 int agp_bind_memory(device_t dev, void *handle, vm_offset_t offset)
960 {
961 	struct agp_memory *mem = (struct agp_memory *) handle;
962 	return AGP_BIND_MEMORY(dev, mem, offset);
963 }
964 
965 int agp_unbind_memory(device_t dev, void *handle)
966 {
967 	struct agp_memory *mem = (struct agp_memory *) handle;
968 	return AGP_UNBIND_MEMORY(dev, mem);
969 }
970 
971 void agp_memory_info(device_t dev, void *handle, struct
972 		     agp_memory_info *mi)
973 {
974 	struct agp_memory *mem = (struct agp_memory *) handle;
975 
976 	mi->ami_size = mem->am_size;
977 	mi->ami_physical = mem->am_physical;
978 	mi->ami_offset = mem->am_offset;
979 	mi->ami_is_bound = mem->am_is_bound;
980 }
981 
982 int
983 agp_bind_pages(device_t dev, vm_page_t *pages, vm_size_t size,
984     vm_offset_t offset)
985 {
986 	struct agp_softc *sc;
987 	vm_offset_t i, j, k, pa;
988 	vm_page_t m;
989 	int error;
990 
991 	if ((size & (AGP_PAGE_SIZE - 1)) != 0 ||
992 	    (offset & (AGP_PAGE_SIZE - 1)) != 0)
993 		return (EINVAL);
994 
995 	sc = device_get_softc(dev);
996 
997 	mtx_lock(&sc->as_lock);
998 	for (i = 0; i < size; i += PAGE_SIZE) {
999 		m = pages[OFF_TO_IDX(i)];
1000 		KASSERT(vm_page_wired(m),
1001 		    ("agp_bind_pages: page %p hasn't been wired", m));
1002 
1003 		/*
1004 		 * Install entries in the GATT, making sure that if
1005 		 * AGP_PAGE_SIZE < PAGE_SIZE and size is not
1006 		 * aligned to PAGE_SIZE, we don't modify too many GATT
1007 		 * entries.
1008 		 */
1009 		for (j = 0; j < PAGE_SIZE && i + j < size; j += AGP_PAGE_SIZE) {
1010 			pa = VM_PAGE_TO_PHYS(m) + j;
1011 			AGP_DPF("binding offset %#jx to pa %#jx\n",
1012 				(uintmax_t)offset + i + j, (uintmax_t)pa);
1013 			error = AGP_BIND_PAGE(dev, offset + i + j, pa);
1014 			if (error) {
1015 				/*
1016 				 * Bail out. Reverse all the mappings.
1017 				 */
1018 				for (k = 0; k < i + j; k += AGP_PAGE_SIZE)
1019 					AGP_UNBIND_PAGE(dev, offset + k);
1020 
1021 				mtx_unlock(&sc->as_lock);
1022 				return (error);
1023 			}
1024 		}
1025 	}
1026 
1027 	AGP_FLUSH_TLB(dev);
1028 
1029 	mtx_unlock(&sc->as_lock);
1030 	return (0);
1031 }
1032 
1033 int
1034 agp_unbind_pages(device_t dev, vm_size_t size, vm_offset_t offset)
1035 {
1036 	struct agp_softc *sc;
1037 	vm_offset_t i;
1038 
1039 	if ((size & (AGP_PAGE_SIZE - 1)) != 0 ||
1040 	    (offset & (AGP_PAGE_SIZE - 1)) != 0)
1041 		return (EINVAL);
1042 
1043 	sc = device_get_softc(dev);
1044 
1045 	mtx_lock(&sc->as_lock);
1046 	for (i = 0; i < size; i += AGP_PAGE_SIZE)
1047 		AGP_UNBIND_PAGE(dev, offset + i);
1048 
1049 	AGP_FLUSH_TLB(dev);
1050 
1051 	mtx_unlock(&sc->as_lock);
1052 	return (0);
1053 }
1054