xref: /dragonfly/sys/dev/agp/agp.c (revision b7367ef6)
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 1.56 2007/07/13 16:28:11 anholt Exp $
27  *	$DragonFly: src/sys/dev/agp/agp.c,v 1.27 2007/09/12 08:31:43 hasso 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/device.h>
36 #include <sys/conf.h>
37 #include <sys/malloc.h>
38 #include <sys/kernel.h>
39 #include <sys/bus.h>
40 #include <sys/ioccom.h>
41 #include <sys/agpio.h>
42 #include <sys/lock.h>
43 #include <sys/proc.h>
44 #include <sys/rman.h>
45 
46 #include <bus/pci/pcivar.h>
47 #include <bus/pci/pcireg.h>
48 #include "agppriv.h"
49 #include "agpvar.h"
50 #include "agpreg.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/md_var.h>
59 
60 MODULE_VERSION(agp, 1);
61 
62 MALLOC_DEFINE(M_AGP, "agp", "AGP data structures");
63 
64 #define CDEV_MAJOR	148
65 				/* agp_drv.c */
66 static d_open_t agp_open;
67 static d_close_t agp_close;
68 static d_ioctl_t agp_ioctl;
69 static d_mmap_t agp_mmap;
70 
71 static struct dev_ops agp_ops = {
72 	{ "agp", CDEV_MAJOR, D_TTY },
73 	.d_open =	agp_open,
74 	.d_close =	agp_close,
75 	.d_ioctl =	agp_ioctl,
76 	.d_mmap =	agp_mmap,
77 };
78 
79 static devclass_t agp_devclass;
80 #define KDEV2DEV(kdev)	devclass_get_device(agp_devclass, minor(kdev))
81 
82 /* Helper functions for implementing chipset mini drivers. */
83 
84 void
85 agp_flush_cache(void)
86 {
87 #if defined(__i386__) || defined(__amd64__)
88 	wbinvd();
89 #endif
90 }
91 
92 u_int8_t
93 agp_find_caps(device_t dev)
94 {
95 	u_int32_t status;
96 	u_int8_t ptr, next;
97 
98 	/*
99 	 * Check the CAP_LIST bit of the PCI status register first.
100 	 */
101 	status = pci_read_config(dev, PCIR_STATUS, 2);
102 	if (!(status & 0x10))
103 		return 0;
104 
105 	/*
106 	 * Traverse the capabilities list.
107 	 */
108 	for (ptr = pci_read_config(dev, AGP_CAPPTR, 1);
109 	     ptr != 0;
110 	     ptr = next) {
111 		u_int32_t capid = pci_read_config(dev, ptr, 4);
112 		next = AGP_CAPID_GET_NEXT_PTR(capid);
113 
114 		/*
115 		 * If this capability entry ID is 2, then we are done.
116 		 */
117 		if (AGP_CAPID_GET_CAP_ID(capid) == 2)
118 			return ptr;
119 	}
120 
121 	return 0;
122 }
123 
124 /*
125  * Find an AGP display device (if any).
126  */
127 static device_t
128 agp_find_display(void)
129 {
130 	devclass_t pci = devclass_find("pci");
131 	device_t bus, dev = 0;
132 	device_t *kids;
133 	int busnum, numkids, i;
134 
135 	for (busnum = 0; busnum < devclass_get_maxunit(pci); busnum++) {
136 		bus = devclass_get_device(pci, busnum);
137 		if (!bus)
138 			continue;
139 		device_get_children(bus, &kids, &numkids);
140 		for (i = 0; i < numkids; i++) {
141 			dev = kids[i];
142 			if (pci_get_class(dev) == PCIC_DISPLAY
143 			    && pci_get_subclass(dev) == PCIS_DISPLAY_VGA)
144 				if (agp_find_caps(dev)) {
145 					kfree(kids, M_TEMP);
146 					return dev;
147 				}
148 
149 		}
150 		kfree(kids, M_TEMP);
151 	}
152 
153 	return 0;
154 }
155 
156 struct agp_gatt *
157 agp_alloc_gatt(device_t dev)
158 {
159 	u_int32_t apsize = AGP_GET_APERTURE(dev);
160 	u_int32_t entries = apsize >> AGP_PAGE_SHIFT;
161 	struct agp_gatt *gatt;
162 
163 	if (bootverbose)
164 		device_printf(dev,
165 			      "allocating GATT for aperture of size %dM\n",
166 			      apsize / (1024*1024));
167 
168 	if (entries == 0) {
169 		device_printf(dev, "bad aperture size\n");
170 		return NULL;
171 	}
172 
173 	gatt = kmalloc(sizeof(struct agp_gatt), M_AGP, M_INTWAIT);
174 	gatt->ag_entries = entries;
175 	gatt->ag_virtual = contigmalloc(entries * sizeof(u_int32_t), M_AGP,
176 					M_WAITOK, 0, ~0, PAGE_SIZE, 0);
177 	if (!gatt->ag_virtual) {
178 		if (bootverbose)
179 			device_printf(dev, "contiguous allocation failed\n");
180 		kfree(gatt, M_AGP);
181 		return 0;
182 	}
183 	bzero(gatt->ag_virtual, entries * sizeof(u_int32_t));
184 	gatt->ag_physical = vtophys((vm_offset_t) gatt->ag_virtual);
185 	agp_flush_cache();
186 
187 	return gatt;
188 }
189 
190 void
191 agp_free_gatt(struct agp_gatt *gatt)
192 {
193 	contigfree(gatt->ag_virtual,
194 		   gatt->ag_entries * sizeof(u_int32_t), M_AGP);
195 	kfree(gatt, M_AGP);
196 }
197 
198 static u_int agp_max[][2] = {
199 	{0,	0},
200 	{32,	4},
201 	{64,	28},
202 	{128,	96},
203 	{256,	204},
204 	{512,	440},
205 	{1024,	942},
206 	{2048,	1920},
207 	{4096,	3932}
208 };
209 #define agp_max_size	(sizeof(agp_max) / sizeof(agp_max[0]))
210 
211 /**
212  * Sets the PCI resource which represents the AGP aperture.
213  *
214  * If not called, the default AGP aperture resource of AGP_APBASE will
215  * be used.  Must be called before agp_generic_attach().
216  */
217 void
218 agp_set_aperture_resource(device_t dev, int rid)
219 {
220 	struct agp_softc *sc = device_get_softc(dev);
221 
222 	sc->as_aperture_rid = rid;
223 }
224 
225 int
226 agp_generic_attach(device_t dev)
227 {
228 	struct agp_softc *sc = device_get_softc(dev);
229 	int i;
230 	u_int memsize;
231 
232 	/*
233 	 * Find and map the aperture, RF_SHAREABLE for DRM but not RF_ACTIVE
234 	 * because the kernel doesn't need to map it.
235 	 */
236 	if (sc->as_aperture_rid == 0)
237 		sc->as_aperture_rid = AGP_APBASE;
238 
239 	sc->as_aperture = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
240 	    &sc->as_aperture_rid, RF_SHAREABLE);
241 	if (!sc->as_aperture)
242 		return ENOMEM;
243 
244 	/*
245 	 * Work out an upper bound for agp memory allocation. This
246 	 * uses a heurisitc table from the Linux driver.
247 	 */
248 	memsize = ptoa(Maxmem) >> 20;
249 	for (i = 0; i < agp_max_size; i++) {
250 		if (memsize <= agp_max[i][0])
251 			break;
252 	}
253 	if (i == agp_max_size) i = agp_max_size - 1;
254 	sc->as_maxmem = agp_max[i][1] << 20U;
255 
256 	/*
257 	 * The lock is used to prevent re-entry to
258 	 * agp_generic_bind_memory() since that function can sleep.
259 	 */
260 	lockinit(&sc->as_lock, "agplk", 0, 0);
261 
262 	/*
263 	 * Initialise stuff for the userland device.
264 	 */
265 	agp_devclass = devclass_find("agp");
266 	TAILQ_INIT(&sc->as_memory);
267 	sc->as_nextid = 1;
268 
269 	dev_ops_add(&agp_ops, -1, device_get_unit(dev));
270 	make_dev(&agp_ops, device_get_unit(dev), UID_ROOT, GID_WHEEL,
271 		  0600, "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 
281 	bus_release_resource(dev, SYS_RES_MEMORY, AGP_APBASE, sc->as_aperture);
282 	agp_flush_cache();
283 	dev_ops_remove(&agp_ops, -1, device_get_unit(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 int
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 (sc->as_allocated + size > sc->as_maxmem)
481 		return 0;
482 
483 	if (type != 0) {
484 		kprintf("agp_generic_alloc_memory: unsupported type %d\n",
485 			type);
486 		return 0;
487 	}
488 
489 	mem = kmalloc(sizeof *mem, M_AGP, M_INTWAIT);
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 	kfree(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 	lockmgr(&sc->as_lock, LK_EXCLUSIVE);
528 
529 	if (mem->am_is_bound) {
530 		device_printf(dev, "memory already bound\n");
531 		lockmgr(&sc->as_lock, LK_RELEASE);
532 		return EINVAL;
533 	}
534 
535 	if (offset < 0
536 	    || (offset & (AGP_PAGE_SIZE - 1)) != 0
537 	    || offset + mem->am_size > AGP_GET_APERTURE(dev)) {
538 		device_printf(dev, "binding memory at bad offset %#x,%#x,%#x\n",
539 			      (int) offset, (int)mem->am_size,
540 			      (int)AGP_GET_APERTURE(dev));
541 		kprintf("Check BIOS's aperature size vs X\n");
542 		lockmgr(&sc->as_lock, LK_RELEASE);
543 		return EINVAL;
544 	}
545 
546 	/*
547 	 * Bind the individual pages and flush the chipset's
548 	 * TLB.
549 	 */
550 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
551 		/*
552 		 * Find a page from the object and wire it
553 		 * down. This page will be mapped using one or more
554 		 * entries in the GATT (assuming that PAGE_SIZE >=
555 		 * AGP_PAGE_SIZE. If this is the first call to bind,
556 		 * the pages will be allocated and zeroed.
557 		 */
558 		m = vm_page_grab(mem->am_obj, OFF_TO_IDX(i),
559 			 VM_ALLOC_NORMAL | VM_ALLOC_ZERO | VM_ALLOC_RETRY);
560 		if ((m->flags & PG_ZERO) == 0)
561 			vm_page_zero_fill(m);
562 		AGP_DPF("found page pa=%#x\n", VM_PAGE_TO_PHYS(m));
563 		vm_page_wire(m);
564 
565 		/*
566 		 * Install entries in the GATT, making sure that if
567 		 * AGP_PAGE_SIZE < PAGE_SIZE and mem->am_size is not
568 		 * aligned to PAGE_SIZE, we don't modify too many GATT
569 		 * entries.
570 		 */
571 		for (j = 0; j < PAGE_SIZE && i + j < mem->am_size;
572 		     j += AGP_PAGE_SIZE) {
573 			vm_offset_t pa = VM_PAGE_TO_PHYS(m) + j;
574 			AGP_DPF("binding offset %#x to pa %#x\n",
575 				offset + i + j, pa);
576 			error = AGP_BIND_PAGE(dev, offset + i + j, pa);
577 			if (error) {
578 				/*
579 				 * Bail out. Reverse all the mappings
580 				 * and unwire the pages.
581 				 */
582 				vm_page_wakeup(m);
583 				for (k = 0; k < i + j; k += AGP_PAGE_SIZE)
584 					AGP_UNBIND_PAGE(dev, offset + k);
585 				for (k = 0; k <= i; k += PAGE_SIZE) {
586 					m = vm_page_lookup(mem->am_obj,
587 							   OFF_TO_IDX(k));
588 					vm_page_unwire(m, 0);
589 				}
590 				lockmgr(&sc->as_lock, LK_RELEASE);
591 				return error;
592 			}
593 		}
594 		vm_page_wakeup(m);
595 	}
596 
597 	/*
598 	 * Flush the cpu cache since we are providing a new mapping
599 	 * for these pages.
600 	 */
601 	agp_flush_cache();
602 
603 	/*
604 	 * Make sure the chipset gets the new mappings.
605 	 */
606 	AGP_FLUSH_TLB(dev);
607 
608 	mem->am_offset = offset;
609 	mem->am_is_bound = 1;
610 
611 	lockmgr(&sc->as_lock, LK_RELEASE);
612 
613 	return 0;
614 }
615 
616 int
617 agp_generic_unbind_memory(device_t dev, struct agp_memory *mem)
618 {
619 	struct agp_softc *sc = device_get_softc(dev);
620 	vm_page_t m;
621 	int i;
622 
623 	lockmgr(&sc->as_lock, LK_EXCLUSIVE);
624 
625 	if (!mem->am_is_bound) {
626 		device_printf(dev, "memory is not bound\n");
627 		lockmgr(&sc->as_lock, LK_RELEASE);
628 		return EINVAL;
629 	}
630 
631 
632 	/*
633 	 * Unbind the individual pages and flush the chipset's
634 	 * TLB. Unwire the pages so they can be swapped.
635 	 */
636 	for (i = 0; i < mem->am_size; i += AGP_PAGE_SIZE)
637 		AGP_UNBIND_PAGE(dev, mem->am_offset + i);
638 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
639 		m = vm_page_lookup(mem->am_obj, atop(i));
640 		vm_page_unwire(m, 0);
641 	}
642 
643 	agp_flush_cache();
644 	AGP_FLUSH_TLB(dev);
645 
646 	mem->am_offset = 0;
647 	mem->am_is_bound = 0;
648 
649 	lockmgr(&sc->as_lock, LK_RELEASE);
650 
651 	return 0;
652 }
653 
654 /* Helper functions for implementing user/kernel api */
655 
656 static int
657 agp_acquire_helper(device_t dev, enum agp_acquire_state state)
658 {
659 	struct agp_softc *sc = device_get_softc(dev);
660 
661 	if (sc->as_state != AGP_ACQUIRE_FREE)
662 		return EBUSY;
663 	sc->as_state = state;
664 
665 	return 0;
666 }
667 
668 static int
669 agp_release_helper(device_t dev, enum agp_acquire_state state)
670 {
671 	struct agp_softc *sc = device_get_softc(dev);
672 
673 	if (sc->as_state == AGP_ACQUIRE_FREE)
674 		return 0;
675 
676 	if (sc->as_state != state)
677 		return EBUSY;
678 
679 	sc->as_state = AGP_ACQUIRE_FREE;
680 	return 0;
681 }
682 
683 static struct agp_memory *
684 agp_find_memory(device_t dev, int id)
685 {
686 	struct agp_softc *sc = device_get_softc(dev);
687 	struct agp_memory *mem;
688 
689 	AGP_DPF("searching for memory block %d\n", id);
690 	TAILQ_FOREACH(mem, &sc->as_memory, am_link) {
691 		AGP_DPF("considering memory block %d\n", mem->am_id);
692 		if (mem->am_id == id)
693 			return mem;
694 	}
695 	return 0;
696 }
697 
698 /* Implementation of the userland ioctl api */
699 
700 static int
701 agp_info_user(device_t dev, agp_info *info)
702 {
703 	struct agp_softc *sc = device_get_softc(dev);
704 
705 	bzero(info, sizeof *info);
706 	info->bridge_id = pci_get_devid(dev);
707 	info->agp_mode =
708 	    pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
709 	info->aper_base = rman_get_start(sc->as_aperture);
710 	info->aper_size = AGP_GET_APERTURE(dev) >> 20;
711 	info->pg_total = info->pg_system = sc->as_maxmem >> AGP_PAGE_SHIFT;
712 	info->pg_used = sc->as_allocated >> AGP_PAGE_SHIFT;
713 
714 	return 0;
715 }
716 
717 static int
718 agp_setup_user(device_t dev, agp_setup *setup)
719 {
720 	return AGP_ENABLE(dev, setup->agp_mode);
721 }
722 
723 static int
724 agp_allocate_user(device_t dev, agp_allocate *alloc)
725 {
726 	struct agp_memory *mem;
727 
728 	mem = AGP_ALLOC_MEMORY(dev,
729 			       alloc->type,
730 			       alloc->pg_count << AGP_PAGE_SHIFT);
731 	if (mem) {
732 		alloc->key = mem->am_id;
733 		alloc->physical = mem->am_physical;
734 		return 0;
735 	} else {
736 		return ENOMEM;
737 	}
738 }
739 
740 static int
741 agp_deallocate_user(device_t dev, int id)
742 {
743 	struct agp_memory *mem = agp_find_memory(dev, id);
744 
745 	if (mem) {
746 		AGP_FREE_MEMORY(dev, mem);
747 		return 0;
748 	} else {
749 		return ENOENT;
750 	}
751 }
752 
753 static int
754 agp_bind_user(device_t dev, agp_bind *bind)
755 {
756 	struct agp_memory *mem = agp_find_memory(dev, bind->key);
757 
758 	if (!mem)
759 		return ENOENT;
760 
761 	return AGP_BIND_MEMORY(dev, mem, bind->pg_start << AGP_PAGE_SHIFT);
762 }
763 
764 static int
765 agp_unbind_user(device_t dev, agp_unbind *unbind)
766 {
767 	struct agp_memory *mem = agp_find_memory(dev, unbind->key);
768 
769 	if (!mem)
770 		return ENOENT;
771 
772 	return AGP_UNBIND_MEMORY(dev, mem);
773 }
774 
775 static int
776 agp_open(struct dev_open_args *ap)
777 {
778 	cdev_t kdev = ap->a_head.a_dev;
779 	device_t dev = KDEV2DEV(kdev);
780 	struct agp_softc *sc = device_get_softc(dev);
781 
782 	if (!sc->as_isopen) {
783 		sc->as_isopen = 1;
784 		device_busy(dev);
785 	}
786 
787 	return 0;
788 }
789 
790 static int
791 agp_close(struct dev_close_args *ap)
792 {
793 	cdev_t kdev = ap->a_head.a_dev;
794 	device_t dev = KDEV2DEV(kdev);
795 	struct agp_softc *sc = device_get_softc(dev);
796 	struct agp_memory *mem;
797 
798 	/*
799 	 * Clear the GATT and force release on last close
800 	 */
801 	while ((mem = TAILQ_FIRST(&sc->as_memory)) != 0) {
802 		if (mem->am_is_bound)
803 			AGP_UNBIND_MEMORY(dev, mem);
804 		AGP_FREE_MEMORY(dev, mem);
805 	}
806 	if (sc->as_state == AGP_ACQUIRE_USER)
807 		agp_release_helper(dev, AGP_ACQUIRE_USER);
808 	sc->as_isopen = 0;
809 	device_unbusy(dev);
810 
811 	return 0;
812 }
813 
814 static int
815 agp_ioctl(struct dev_ioctl_args *ap)
816 {
817 	cdev_t kdev = ap->a_head.a_dev;
818 	device_t dev = KDEV2DEV(kdev);
819 
820 	switch (ap->a_cmd) {
821 	case AGPIOC_INFO:
822 		return agp_info_user(dev, (agp_info *)ap->a_data);
823 
824 	case AGPIOC_ACQUIRE:
825 		return agp_acquire_helper(dev, AGP_ACQUIRE_USER);
826 
827 	case AGPIOC_RELEASE:
828 		return agp_release_helper(dev, AGP_ACQUIRE_USER);
829 
830 	case AGPIOC_SETUP:
831 		return agp_setup_user(dev, (agp_setup *)ap->a_data);
832 
833 	case AGPIOC_ALLOCATE:
834 		return agp_allocate_user(dev, (agp_allocate *)ap->a_data);
835 
836 	case AGPIOC_DEALLOCATE:
837 		return agp_deallocate_user(dev, *(int *)ap->a_data);
838 
839 	case AGPIOC_BIND:
840 		return agp_bind_user(dev, (agp_bind *)ap->a_data);
841 
842 	case AGPIOC_UNBIND:
843 		return agp_unbind_user(dev, (agp_unbind *)ap->a_data);
844 
845 	}
846 
847 	return EINVAL;
848 }
849 
850 static int
851 agp_mmap(struct dev_mmap_args *ap)
852 {
853 	cdev_t kdev = ap->a_head.a_dev;
854 	device_t dev = KDEV2DEV(kdev);
855 	struct agp_softc *sc = device_get_softc(dev);
856 
857 	if (ap->a_offset > AGP_GET_APERTURE(dev))
858 		return EINVAL;
859 	ap->a_result = atop(rman_get_start(sc->as_aperture) + ap->a_offset);
860 	return 0;
861 }
862 
863 /* Implementation of the kernel api */
864 
865 device_t
866 agp_find_device(void)
867 {
868 	device_t *children, child;
869 	int i, count;
870 
871 	if (!agp_devclass)
872 		return NULL;
873 	if (devclass_get_devices(agp_devclass, &children, &count) != 0)
874 		return NULL;
875 	child = NULL;
876 	for (i = 0; i < count; i++) {
877 		if (device_is_attached(children[i])) {
878 			child = children[i];
879 			break;
880 		}
881 	}
882 	kfree(children, M_TEMP);
883 	return child;
884 }
885 
886 enum agp_acquire_state
887 agp_state(device_t dev)
888 {
889 	struct agp_softc *sc = device_get_softc(dev);
890 	return sc->as_state;
891 }
892 
893 void
894 agp_get_info(device_t dev, struct agp_info *info)
895 {
896 	struct agp_softc *sc = device_get_softc(dev);
897 
898 	info->ai_mode =
899 		pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
900 	info->ai_aperture_base = rman_get_start(sc->as_aperture);
901 	info->ai_aperture_size = rman_get_size(sc->as_aperture);
902 	info->ai_memory_allowed = sc->as_maxmem;
903 	info->ai_memory_used = sc->as_allocated;
904 }
905 
906 int
907 agp_acquire(device_t dev)
908 {
909 	return agp_acquire_helper(dev, AGP_ACQUIRE_KERNEL);
910 }
911 
912 int
913 agp_release(device_t dev)
914 {
915 	return agp_release_helper(dev, AGP_ACQUIRE_KERNEL);
916 }
917 
918 int
919 agp_enable(device_t dev, u_int32_t mode)
920 {
921 	return AGP_ENABLE(dev, mode);
922 }
923 
924 void *agp_alloc_memory(device_t dev, int type, vm_size_t bytes)
925 {
926 	return  (void *) AGP_ALLOC_MEMORY(dev, type, bytes);
927 }
928 
929 void agp_free_memory(device_t dev, void *handle)
930 {
931 	struct agp_memory *mem = (struct agp_memory *) handle;
932 	AGP_FREE_MEMORY(dev, mem);
933 }
934 
935 int agp_bind_memory(device_t dev, void *handle, vm_offset_t offset)
936 {
937 	struct agp_memory *mem = (struct agp_memory *) handle;
938 	return AGP_BIND_MEMORY(dev, mem, offset);
939 }
940 
941 int agp_unbind_memory(device_t dev, void *handle)
942 {
943 	struct agp_memory *mem = (struct agp_memory *) handle;
944 	return AGP_UNBIND_MEMORY(dev, mem);
945 }
946 
947 void agp_memory_info(device_t dev, void *handle, struct
948 		     agp_memory_info *mi)
949 {
950 	struct agp_memory *mem = (struct agp_memory *) handle;
951 
952 	mi->ami_size = mem->am_size;
953 	mi->ami_physical = mem->am_physical;
954 	mi->ami_offset = mem->am_offset;
955 	mi->ami_is_bound = mem->am_is_bound;
956 }
957