xref: /freebsd/sys/dev/agp/agp.c (revision 3fe92528afe8313fecf48822dde74bad5e380f48)
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_bus.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 
45 #include <dev/pci/pcivar.h>
46 #include <dev/pci/pcireg.h>
47 #include <pci/agppriv.h>
48 #include <pci/agpvar.h>
49 #include <pci/agpreg.h>
50 
51 #include <vm/vm.h>
52 #include <vm/vm_object.h>
53 #include <vm/vm_page.h>
54 #include <vm/vm_pageout.h>
55 #include <vm/pmap.h>
56 
57 #include <machine/md_var.h>
58 #include <machine/bus.h>
59 #include <machine/resource.h>
60 #include <sys/rman.h>
61 
62 MODULE_VERSION(agp, 1);
63 
64 MALLOC_DEFINE(M_AGP, "agp", "AGP data structures");
65 
66 				/* agp_drv.c */
67 static d_open_t agp_open;
68 static d_close_t agp_close;
69 static d_ioctl_t agp_ioctl;
70 static d_mmap_t agp_mmap;
71 
72 static struct cdevsw agp_cdevsw = {
73 	.d_version =	D_VERSION,
74 	.d_flags =	D_NEEDGIANT,
75 	.d_open =	agp_open,
76 	.d_close =	agp_close,
77 	.d_ioctl =	agp_ioctl,
78 	.d_mmap =	agp_mmap,
79 	.d_name =	"agp",
80 };
81 
82 static devclass_t agp_devclass;
83 #define KDEV2DEV(kdev)	devclass_get_device(agp_devclass, minor(kdev))
84 
85 /* Helper functions for implementing chipset mini drivers. */
86 
87 void
88 agp_flush_cache()
89 {
90 #if defined(__i386__) || defined(__amd64__)
91 	wbinvd();
92 #endif
93 }
94 
95 u_int8_t
96 agp_find_caps(device_t dev)
97 {
98 	int capreg;
99 
100 
101 	if (pci_find_extcap(dev, PCIY_AGP, &capreg) != 0)
102 		capreg = 0;
103 	return (capreg);
104 }
105 
106 /*
107  * Find an AGP display device (if any).
108  */
109 static device_t
110 agp_find_display(void)
111 {
112 	devclass_t pci = devclass_find("pci");
113 	device_t bus, dev = 0;
114 	device_t *kids;
115 	int busnum, numkids, i;
116 
117 	for (busnum = 0; busnum < devclass_get_maxunit(pci); busnum++) {
118 		bus = devclass_get_device(pci, busnum);
119 		if (!bus)
120 			continue;
121 		device_get_children(bus, &kids, &numkids);
122 		for (i = 0; i < numkids; i++) {
123 			dev = kids[i];
124 			if (pci_get_class(dev) == PCIC_DISPLAY
125 			    && pci_get_subclass(dev) == PCIS_DISPLAY_VGA)
126 				if (agp_find_caps(dev)) {
127 					free(kids, M_TEMP);
128 					return dev;
129 				}
130 
131 		}
132 		free(kids, M_TEMP);
133 	}
134 
135 	return 0;
136 }
137 
138 struct agp_gatt *
139 agp_alloc_gatt(device_t dev)
140 {
141 	u_int32_t apsize = AGP_GET_APERTURE(dev);
142 	u_int32_t entries = apsize >> AGP_PAGE_SHIFT;
143 	struct agp_gatt *gatt;
144 
145 	if (bootverbose)
146 		device_printf(dev,
147 			      "allocating GATT for aperture of size %dM\n",
148 			      apsize / (1024*1024));
149 
150 	if (entries == 0) {
151 		device_printf(dev, "bad aperture size\n");
152 		return NULL;
153 	}
154 
155 	gatt = malloc(sizeof(struct agp_gatt), M_AGP, M_NOWAIT);
156 	if (!gatt)
157 		return 0;
158 
159 	gatt->ag_entries = entries;
160 	gatt->ag_virtual = contigmalloc(entries * sizeof(u_int32_t), M_AGP, 0,
161 					0, ~0, PAGE_SIZE, 0);
162 	if (!gatt->ag_virtual) {
163 		if (bootverbose)
164 			device_printf(dev, "contiguous allocation failed\n");
165 		free(gatt, M_AGP);
166 		return 0;
167 	}
168 	bzero(gatt->ag_virtual, entries * sizeof(u_int32_t));
169 	gatt->ag_physical = vtophys((vm_offset_t) gatt->ag_virtual);
170 	agp_flush_cache();
171 
172 	return gatt;
173 }
174 
175 void
176 agp_free_gatt(struct agp_gatt *gatt)
177 {
178 	contigfree(gatt->ag_virtual,
179 		   gatt->ag_entries * sizeof(u_int32_t), M_AGP);
180 	free(gatt, M_AGP);
181 }
182 
183 static int agp_max[][2] = {
184 	{0,	0},
185 	{32,	4},
186 	{64,	28},
187 	{128,	96},
188 	{256,	204},
189 	{512,	440},
190 	{1024,	942},
191 	{2048,	1920},
192 	{4096,	3932}
193 };
194 #define agp_max_size	(sizeof(agp_max) / sizeof(agp_max[0]))
195 
196 int
197 agp_generic_attach(device_t dev)
198 {
199 	struct agp_softc *sc = device_get_softc(dev);
200 	int rid, memsize, i;
201 
202 	/*
203 	 * Find and map the aperture.
204 	 */
205 	rid = AGP_APBASE;
206 	sc->as_aperture = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, 0);
207 	if (!sc->as_aperture)
208 		return ENOMEM;
209 
210 	/*
211 	 * Work out an upper bound for agp memory allocation. This
212 	 * uses a heurisitc table from the Linux driver.
213 	 */
214 	memsize = ptoa(Maxmem) >> 20;
215 	for (i = 0; i < agp_max_size; i++) {
216 		if (memsize <= agp_max[i][0])
217 			break;
218 	}
219 	if (i == agp_max_size) i = agp_max_size - 1;
220 	sc->as_maxmem = agp_max[i][1] << 20U;
221 
222 	/*
223 	 * The lock is used to prevent re-entry to
224 	 * agp_generic_bind_memory() since that function can sleep.
225 	 */
226 	mtx_init(&sc->as_lock, "agp lock", NULL, MTX_DEF);
227 
228 	/*
229 	 * Initialise stuff for the userland device.
230 	 */
231 	agp_devclass = devclass_find("agp");
232 	TAILQ_INIT(&sc->as_memory);
233 	sc->as_nextid = 1;
234 
235 	sc->as_devnode = make_dev(&agp_cdevsw,
236 				  device_get_unit(dev),
237 				  UID_ROOT,
238 				  GID_WHEEL,
239 				  0600,
240 				  "agpgart");
241 
242 	return 0;
243 }
244 
245 int
246 agp_generic_detach(device_t dev)
247 {
248 	struct agp_softc *sc = device_get_softc(dev);
249 
250 	destroy_dev(sc->as_devnode);
251 	bus_release_resource(dev, SYS_RES_MEMORY, AGP_APBASE, sc->as_aperture);
252 	mtx_destroy(&sc->as_lock);
253 	agp_flush_cache();
254 	return 0;
255 }
256 
257 /*
258  * This does the enable logic for v3, with the same topology
259  * restrictions as in place for v2 -- one bus, one device on the bus.
260  */
261 static int
262 agp_v3_enable(device_t dev, device_t mdev, u_int32_t mode)
263 {
264 	u_int32_t tstatus, mstatus;
265 	u_int32_t command;
266 	int rq, sba, fw, rate, arqsz, cal;
267 
268 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
269 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
270 
271 	/* Set RQ to the min of mode, tstatus and mstatus */
272 	rq = AGP_MODE_GET_RQ(mode);
273 	if (AGP_MODE_GET_RQ(tstatus) < rq)
274 		rq = AGP_MODE_GET_RQ(tstatus);
275 	if (AGP_MODE_GET_RQ(mstatus) < rq)
276 		rq = AGP_MODE_GET_RQ(mstatus);
277 
278 	/*
279 	 * ARQSZ - Set the value to the maximum one.
280 	 * Don't allow the mode register to override values.
281 	 */
282 	arqsz = AGP_MODE_GET_ARQSZ(mode);
283 	if (AGP_MODE_GET_ARQSZ(tstatus) > rq)
284 		rq = AGP_MODE_GET_ARQSZ(tstatus);
285 	if (AGP_MODE_GET_ARQSZ(mstatus) > rq)
286 		rq = AGP_MODE_GET_ARQSZ(mstatus);
287 
288 	/* Calibration cycle - don't allow override by mode register */
289 	cal = AGP_MODE_GET_CAL(tstatus);
290 	if (AGP_MODE_GET_CAL(mstatus) < cal)
291 		cal = AGP_MODE_GET_CAL(mstatus);
292 
293 	/* SBA must be supported for AGP v3. */
294 	sba = 1;
295 
296 	/* Set FW if all three support it. */
297 	fw = (AGP_MODE_GET_FW(tstatus)
298 	       & AGP_MODE_GET_FW(mstatus)
299 	       & AGP_MODE_GET_FW(mode));
300 
301 	/* Figure out the max rate */
302 	rate = (AGP_MODE_GET_RATE(tstatus)
303 		& AGP_MODE_GET_RATE(mstatus)
304 		& AGP_MODE_GET_RATE(mode));
305 	if (rate & AGP_MODE_V3_RATE_8x)
306 		rate = AGP_MODE_V3_RATE_8x;
307 	else
308 		rate = AGP_MODE_V3_RATE_4x;
309 	if (bootverbose)
310 		device_printf(dev, "Setting AGP v3 mode %d\n", rate * 4);
311 
312 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, 0, 4);
313 
314 	/* Construct the new mode word and tell the hardware */
315 	command = 0;
316 	command = AGP_MODE_SET_RQ(0, rq);
317 	command = AGP_MODE_SET_ARQSZ(command, arqsz);
318 	command = AGP_MODE_SET_CAL(command, cal);
319 	command = AGP_MODE_SET_SBA(command, sba);
320 	command = AGP_MODE_SET_FW(command, fw);
321 	command = AGP_MODE_SET_RATE(command, rate);
322 	command = AGP_MODE_SET_MODE_3(command, 1);
323 	command = AGP_MODE_SET_AGP(command, 1);
324 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
325 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
326 
327 	return 0;
328 }
329 
330 static int
331 agp_v2_enable(device_t dev, device_t mdev, u_int32_t mode)
332 {
333 	u_int32_t tstatus, mstatus;
334 	u_int32_t command;
335 	int rq, sba, fw, rate;
336 
337 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
338 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
339 
340 	/* Set RQ to the min of mode, tstatus and mstatus */
341 	rq = AGP_MODE_GET_RQ(mode);
342 	if (AGP_MODE_GET_RQ(tstatus) < rq)
343 		rq = AGP_MODE_GET_RQ(tstatus);
344 	if (AGP_MODE_GET_RQ(mstatus) < rq)
345 		rq = AGP_MODE_GET_RQ(mstatus);
346 
347 	/* Set SBA if all three can deal with SBA */
348 	sba = (AGP_MODE_GET_SBA(tstatus)
349 	       & AGP_MODE_GET_SBA(mstatus)
350 	       & AGP_MODE_GET_SBA(mode));
351 
352 	/* Similar for FW */
353 	fw = (AGP_MODE_GET_FW(tstatus)
354 	       & AGP_MODE_GET_FW(mstatus)
355 	       & AGP_MODE_GET_FW(mode));
356 
357 	/* Figure out the max rate */
358 	rate = (AGP_MODE_GET_RATE(tstatus)
359 		& AGP_MODE_GET_RATE(mstatus)
360 		& AGP_MODE_GET_RATE(mode));
361 	if (rate & AGP_MODE_V2_RATE_4x)
362 		rate = AGP_MODE_V2_RATE_4x;
363 	else if (rate & AGP_MODE_V2_RATE_2x)
364 		rate = AGP_MODE_V2_RATE_2x;
365 	else
366 		rate = AGP_MODE_V2_RATE_1x;
367 	if (bootverbose)
368 		device_printf(dev, "Setting AGP v2 mode %d\n", rate);
369 
370 	/* Construct the new mode word and tell the hardware */
371 	command = 0;
372 	command = AGP_MODE_SET_RQ(0, rq);
373 	command = AGP_MODE_SET_SBA(command, sba);
374 	command = AGP_MODE_SET_FW(command, fw);
375 	command = AGP_MODE_SET_RATE(command, rate);
376 	command = AGP_MODE_SET_AGP(command, 1);
377 	pci_write_config(dev, agp_find_caps(dev) + AGP_COMMAND, command, 4);
378 	pci_write_config(mdev, agp_find_caps(mdev) + AGP_COMMAND, command, 4);
379 
380 	return 0;
381 }
382 
383 int
384 agp_generic_enable(device_t dev, u_int32_t mode)
385 {
386 	device_t mdev = agp_find_display();
387 	u_int32_t tstatus, mstatus;
388 
389 	if (!mdev) {
390 		AGP_DPF("can't find display\n");
391 		return ENXIO;
392 	}
393 
394 	tstatus = pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
395 	mstatus = pci_read_config(mdev, agp_find_caps(mdev) + AGP_STATUS, 4);
396 
397 	/*
398 	 * Check display and bridge for AGP v3 support.  AGP v3 allows
399 	 * more variety in topology than v2, e.g. multiple AGP devices
400 	 * attached to one bridge, or multiple AGP bridges in one
401 	 * system.  This doesn't attempt to address those situations,
402 	 * but should work fine for a classic single AGP slot system
403 	 * with AGP v3.
404 	 */
405 	if (AGP_MODE_GET_MODE_3(mode) &&
406 	    AGP_MODE_GET_MODE_3(tstatus) &&
407 	    AGP_MODE_GET_MODE_3(mstatus))
408 		return (agp_v3_enable(dev, mdev, mode));
409 	else
410 		return (agp_v2_enable(dev, mdev, mode));
411 }
412 
413 struct agp_memory *
414 agp_generic_alloc_memory(device_t dev, int type, vm_size_t size)
415 {
416 	struct agp_softc *sc = device_get_softc(dev);
417 	struct agp_memory *mem;
418 
419 	if ((size & (AGP_PAGE_SIZE - 1)) != 0)
420 		return 0;
421 
422 	if (sc->as_allocated + size > sc->as_maxmem)
423 		return 0;
424 
425 	if (type != 0) {
426 		printf("agp_generic_alloc_memory: unsupported type %d\n",
427 		       type);
428 		return 0;
429 	}
430 
431 	mem = malloc(sizeof *mem, M_AGP, M_WAITOK);
432 	mem->am_id = sc->as_nextid++;
433 	mem->am_size = size;
434 	mem->am_type = 0;
435 	mem->am_obj = vm_object_allocate(OBJT_DEFAULT, atop(round_page(size)));
436 	mem->am_physical = 0;
437 	mem->am_offset = 0;
438 	mem->am_is_bound = 0;
439 	TAILQ_INSERT_TAIL(&sc->as_memory, mem, am_link);
440 	sc->as_allocated += size;
441 
442 	return mem;
443 }
444 
445 int
446 agp_generic_free_memory(device_t dev, struct agp_memory *mem)
447 {
448 	struct agp_softc *sc = device_get_softc(dev);
449 
450 	if (mem->am_is_bound)
451 		return EBUSY;
452 
453 	sc->as_allocated -= mem->am_size;
454 	TAILQ_REMOVE(&sc->as_memory, mem, am_link);
455 	vm_object_deallocate(mem->am_obj);
456 	free(mem, M_AGP);
457 	return 0;
458 }
459 
460 int
461 agp_generic_bind_memory(device_t dev, struct agp_memory *mem,
462 			vm_offset_t offset)
463 {
464 	struct agp_softc *sc = device_get_softc(dev);
465 	vm_offset_t i, j, k;
466 	vm_page_t m;
467 	int error;
468 
469 	/* Do some sanity checks first. */
470 	if (offset < 0 || (offset & (AGP_PAGE_SIZE - 1)) != 0 ||
471 	    offset + mem->am_size > AGP_GET_APERTURE(dev)) {
472 		device_printf(dev, "binding memory at bad offset %#x\n",
473 		    (int)offset);
474 		return EINVAL;
475 	}
476 
477 	/*
478 	 * Allocate the pages early, before acquiring the lock,
479 	 * because vm_page_grab() used with VM_ALLOC_RETRY may
480 	 * block and we can't hold a mutex while blocking.
481 	 */
482 	VM_OBJECT_LOCK(mem->am_obj);
483 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
484 		/*
485 		 * Find a page from the object and wire it
486 		 * down. This page will be mapped using one or more
487 		 * entries in the GATT (assuming that PAGE_SIZE >=
488 		 * AGP_PAGE_SIZE. If this is the first call to bind,
489 		 * the pages will be allocated and zeroed.
490 		 */
491 		m = vm_page_grab(mem->am_obj, OFF_TO_IDX(i),
492 		    VM_ALLOC_WIRED | VM_ALLOC_ZERO | VM_ALLOC_RETRY);
493 		AGP_DPF("found page pa=%#x\n", VM_PAGE_TO_PHYS(m));
494 	}
495 	VM_OBJECT_UNLOCK(mem->am_obj);
496 
497 	mtx_lock(&sc->as_lock);
498 
499 	if (mem->am_is_bound) {
500 		device_printf(dev, "memory already bound\n");
501 		error = EINVAL;
502 		VM_OBJECT_LOCK(mem->am_obj);
503 		goto bad;
504 	}
505 
506 	/*
507 	 * Bind the individual pages and flush the chipset's
508 	 * TLB.
509 	 */
510 	VM_OBJECT_LOCK(mem->am_obj);
511 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
512 		m = vm_page_lookup(mem->am_obj, OFF_TO_IDX(i));
513 
514 		/*
515 		 * Install entries in the GATT, making sure that if
516 		 * AGP_PAGE_SIZE < PAGE_SIZE and mem->am_size is not
517 		 * aligned to PAGE_SIZE, we don't modify too many GATT
518 		 * entries.
519 		 */
520 		for (j = 0; j < PAGE_SIZE && i + j < mem->am_size;
521 		     j += AGP_PAGE_SIZE) {
522 			vm_offset_t pa = VM_PAGE_TO_PHYS(m) + j;
523 			AGP_DPF("binding offset %#x to pa %#x\n",
524 				offset + i + j, pa);
525 			error = AGP_BIND_PAGE(dev, offset + i + j, pa);
526 			if (error) {
527 				/*
528 				 * Bail out. Reverse all the mappings
529 				 * and unwire the pages.
530 				 */
531 				vm_page_lock_queues();
532 				vm_page_wakeup(m);
533 				vm_page_unlock_queues();
534 				for (k = 0; k < i + j; k += AGP_PAGE_SIZE)
535 					AGP_UNBIND_PAGE(dev, offset + k);
536 				goto bad;
537 			}
538 		}
539 		vm_page_lock_queues();
540 		vm_page_wakeup(m);
541 		vm_page_unlock_queues();
542 	}
543 	VM_OBJECT_UNLOCK(mem->am_obj);
544 
545 	/*
546 	 * Flush the cpu cache since we are providing a new mapping
547 	 * for these pages.
548 	 */
549 	agp_flush_cache();
550 
551 	/*
552 	 * Make sure the chipset gets the new mappings.
553 	 */
554 	AGP_FLUSH_TLB(dev);
555 
556 	mem->am_offset = offset;
557 	mem->am_is_bound = 1;
558 
559 	mtx_unlock(&sc->as_lock);
560 
561 	return 0;
562 bad:
563 	mtx_unlock(&sc->as_lock);
564 	VM_OBJECT_LOCK_ASSERT(mem->am_obj, MA_OWNED);
565 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
566 		m = vm_page_lookup(mem->am_obj, OFF_TO_IDX(i));
567 		vm_page_lock_queues();
568 		vm_page_unwire(m, 0);
569 		vm_page_unlock_queues();
570 	}
571 	VM_OBJECT_UNLOCK(mem->am_obj);
572 
573 	return error;
574 }
575 
576 int
577 agp_generic_unbind_memory(device_t dev, struct agp_memory *mem)
578 {
579 	struct agp_softc *sc = device_get_softc(dev);
580 	vm_page_t m;
581 	int i;
582 
583 	mtx_lock(&sc->as_lock);
584 
585 	if (!mem->am_is_bound) {
586 		device_printf(dev, "memory is not bound\n");
587 		mtx_unlock(&sc->as_lock);
588 		return EINVAL;
589 	}
590 
591 
592 	/*
593 	 * Unbind the individual pages and flush the chipset's
594 	 * TLB. Unwire the pages so they can be swapped.
595 	 */
596 	for (i = 0; i < mem->am_size; i += AGP_PAGE_SIZE)
597 		AGP_UNBIND_PAGE(dev, mem->am_offset + i);
598 	VM_OBJECT_LOCK(mem->am_obj);
599 	for (i = 0; i < mem->am_size; i += PAGE_SIZE) {
600 		m = vm_page_lookup(mem->am_obj, atop(i));
601 		vm_page_lock_queues();
602 		vm_page_unwire(m, 0);
603 		vm_page_unlock_queues();
604 	}
605 	VM_OBJECT_UNLOCK(mem->am_obj);
606 
607 	agp_flush_cache();
608 	AGP_FLUSH_TLB(dev);
609 
610 	mem->am_offset = 0;
611 	mem->am_is_bound = 0;
612 
613 	mtx_unlock(&sc->as_lock);
614 
615 	return 0;
616 }
617 
618 /* Helper functions for implementing user/kernel api */
619 
620 static int
621 agp_acquire_helper(device_t dev, enum agp_acquire_state state)
622 {
623 	struct agp_softc *sc = device_get_softc(dev);
624 
625 	if (sc->as_state != AGP_ACQUIRE_FREE)
626 		return EBUSY;
627 	sc->as_state = state;
628 
629 	return 0;
630 }
631 
632 static int
633 agp_release_helper(device_t dev, enum agp_acquire_state state)
634 {
635 	struct agp_softc *sc = device_get_softc(dev);
636 
637 	if (sc->as_state == AGP_ACQUIRE_FREE)
638 		return 0;
639 
640 	if (sc->as_state != state)
641 		return EBUSY;
642 
643 	sc->as_state = AGP_ACQUIRE_FREE;
644 	return 0;
645 }
646 
647 static struct agp_memory *
648 agp_find_memory(device_t dev, int id)
649 {
650 	struct agp_softc *sc = device_get_softc(dev);
651 	struct agp_memory *mem;
652 
653 	AGP_DPF("searching for memory block %d\n", id);
654 	TAILQ_FOREACH(mem, &sc->as_memory, am_link) {
655 		AGP_DPF("considering memory block %d\n", mem->am_id);
656 		if (mem->am_id == id)
657 			return mem;
658 	}
659 	return 0;
660 }
661 
662 /* Implementation of the userland ioctl api */
663 
664 static int
665 agp_info_user(device_t dev, agp_info *info)
666 {
667 	struct agp_softc *sc = device_get_softc(dev);
668 
669 	bzero(info, sizeof *info);
670 	info->bridge_id = pci_get_devid(dev);
671 	info->agp_mode =
672 	    pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
673 	info->aper_base = rman_get_start(sc->as_aperture);
674 	info->aper_size = AGP_GET_APERTURE(dev) >> 20;
675 	info->pg_total = info->pg_system = sc->as_maxmem >> AGP_PAGE_SHIFT;
676 	info->pg_used = sc->as_allocated >> AGP_PAGE_SHIFT;
677 
678 	return 0;
679 }
680 
681 static int
682 agp_setup_user(device_t dev, agp_setup *setup)
683 {
684 	return AGP_ENABLE(dev, setup->agp_mode);
685 }
686 
687 static int
688 agp_allocate_user(device_t dev, agp_allocate *alloc)
689 {
690 	struct agp_memory *mem;
691 
692 	mem = AGP_ALLOC_MEMORY(dev,
693 			       alloc->type,
694 			       alloc->pg_count << AGP_PAGE_SHIFT);
695 	if (mem) {
696 		alloc->key = mem->am_id;
697 		alloc->physical = mem->am_physical;
698 		return 0;
699 	} else {
700 		return ENOMEM;
701 	}
702 }
703 
704 static int
705 agp_deallocate_user(device_t dev, int id)
706 {
707 	struct agp_memory *mem = agp_find_memory(dev, id);;
708 
709 	if (mem) {
710 		AGP_FREE_MEMORY(dev, mem);
711 		return 0;
712 	} else {
713 		return ENOENT;
714 	}
715 }
716 
717 static int
718 agp_bind_user(device_t dev, agp_bind *bind)
719 {
720 	struct agp_memory *mem = agp_find_memory(dev, bind->key);
721 
722 	if (!mem)
723 		return ENOENT;
724 
725 	return AGP_BIND_MEMORY(dev, mem, bind->pg_start << AGP_PAGE_SHIFT);
726 }
727 
728 static int
729 agp_unbind_user(device_t dev, agp_unbind *unbind)
730 {
731 	struct agp_memory *mem = agp_find_memory(dev, unbind->key);
732 
733 	if (!mem)
734 		return ENOENT;
735 
736 	return AGP_UNBIND_MEMORY(dev, mem);
737 }
738 
739 static int
740 agp_open(struct cdev *kdev, int oflags, int devtype, struct thread *td)
741 {
742 	device_t dev = KDEV2DEV(kdev);
743 	struct agp_softc *sc = device_get_softc(dev);
744 
745 	if (!sc->as_isopen) {
746 		sc->as_isopen = 1;
747 		device_busy(dev);
748 	}
749 
750 	return 0;
751 }
752 
753 static int
754 agp_close(struct cdev *kdev, int fflag, int devtype, struct thread *td)
755 {
756 	device_t dev = KDEV2DEV(kdev);
757 	struct agp_softc *sc = device_get_softc(dev);
758 	struct agp_memory *mem;
759 
760 	/*
761 	 * Clear the GATT and force release on last close
762 	 */
763 	while ((mem = TAILQ_FIRST(&sc->as_memory)) != 0) {
764 		if (mem->am_is_bound)
765 			AGP_UNBIND_MEMORY(dev, mem);
766 		AGP_FREE_MEMORY(dev, mem);
767 	}
768 	if (sc->as_state == AGP_ACQUIRE_USER)
769 		agp_release_helper(dev, AGP_ACQUIRE_USER);
770 	sc->as_isopen = 0;
771 	device_unbusy(dev);
772 
773 	return 0;
774 }
775 
776 static int
777 agp_ioctl(struct cdev *kdev, u_long cmd, caddr_t data, int fflag, struct thread *td)
778 {
779 	device_t dev = KDEV2DEV(kdev);
780 
781 	switch (cmd) {
782 	case AGPIOC_INFO:
783 		return agp_info_user(dev, (agp_info *) data);
784 
785 	case AGPIOC_ACQUIRE:
786 		return agp_acquire_helper(dev, AGP_ACQUIRE_USER);
787 
788 	case AGPIOC_RELEASE:
789 		return agp_release_helper(dev, AGP_ACQUIRE_USER);
790 
791 	case AGPIOC_SETUP:
792 		return agp_setup_user(dev, (agp_setup *)data);
793 
794 	case AGPIOC_ALLOCATE:
795 		return agp_allocate_user(dev, (agp_allocate *)data);
796 
797 	case AGPIOC_DEALLOCATE:
798 		return agp_deallocate_user(dev, *(int *) data);
799 
800 	case AGPIOC_BIND:
801 		return agp_bind_user(dev, (agp_bind *)data);
802 
803 	case AGPIOC_UNBIND:
804 		return agp_unbind_user(dev, (agp_unbind *)data);
805 
806 	}
807 
808 	return EINVAL;
809 }
810 
811 static int
812 agp_mmap(struct cdev *kdev, vm_offset_t offset, vm_paddr_t *paddr, int prot)
813 {
814 	device_t dev = KDEV2DEV(kdev);
815 	struct agp_softc *sc = device_get_softc(dev);
816 
817 	if (offset > AGP_GET_APERTURE(dev))
818 		return -1;
819 	*paddr = rman_get_start(sc->as_aperture) + offset;
820 	return 0;
821 }
822 
823 /* Implementation of the kernel api */
824 
825 device_t
826 agp_find_device()
827 {
828 	device_t *children, child;
829 	int i, count;
830 
831 	if (!agp_devclass)
832 		return NULL;
833 	if (devclass_get_devices(agp_devclass, &children, &count) != 0)
834 		return NULL;
835 	child = NULL;
836 	for (i = 0; i < count; i++) {
837 		if (device_is_attached(children[i])) {
838 			child = children[i];
839 			break;
840 		}
841 	}
842 	free(children, M_TEMP);
843 	return child;
844 }
845 
846 enum agp_acquire_state
847 agp_state(device_t dev)
848 {
849 	struct agp_softc *sc = device_get_softc(dev);
850 	return sc->as_state;
851 }
852 
853 void
854 agp_get_info(device_t dev, struct agp_info *info)
855 {
856 	struct agp_softc *sc = device_get_softc(dev);
857 
858 	info->ai_mode =
859 		pci_read_config(dev, agp_find_caps(dev) + AGP_STATUS, 4);
860 	info->ai_aperture_base = rman_get_start(sc->as_aperture);
861 	info->ai_aperture_size = rman_get_size(sc->as_aperture);
862 	info->ai_memory_allowed = sc->as_maxmem;
863 	info->ai_memory_used = sc->as_allocated;
864 }
865 
866 int
867 agp_acquire(device_t dev)
868 {
869 	return agp_acquire_helper(dev, AGP_ACQUIRE_KERNEL);
870 }
871 
872 int
873 agp_release(device_t dev)
874 {
875 	return agp_release_helper(dev, AGP_ACQUIRE_KERNEL);
876 }
877 
878 int
879 agp_enable(device_t dev, u_int32_t mode)
880 {
881 	return AGP_ENABLE(dev, mode);
882 }
883 
884 void *agp_alloc_memory(device_t dev, int type, vm_size_t bytes)
885 {
886 	return  (void *) AGP_ALLOC_MEMORY(dev, type, bytes);
887 }
888 
889 void agp_free_memory(device_t dev, void *handle)
890 {
891 	struct agp_memory *mem = (struct agp_memory *) handle;
892 	AGP_FREE_MEMORY(dev, mem);
893 }
894 
895 int agp_bind_memory(device_t dev, void *handle, vm_offset_t offset)
896 {
897 	struct agp_memory *mem = (struct agp_memory *) handle;
898 	return AGP_BIND_MEMORY(dev, mem, offset);
899 }
900 
901 int agp_unbind_memory(device_t dev, void *handle)
902 {
903 	struct agp_memory *mem = (struct agp_memory *) handle;
904 	return AGP_UNBIND_MEMORY(dev, mem);
905 }
906 
907 void agp_memory_info(device_t dev, void *handle, struct
908 		     agp_memory_info *mi)
909 {
910 	struct agp_memory *mem = (struct agp_memory *) handle;
911 
912 	mi->ami_size = mem->am_size;
913 	mi->ami_physical = mem->am_physical;
914 	mi->ami_offset = mem->am_offset;
915 	mi->ami_is_bound = mem->am_is_bound;
916 }
917