1 /*-
2 * Copyright (c) 1997, 1998 Justin T. Gibbs.
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 * without modification, immediately at the beginning of the file.
11 * 2. The name of the author may not be used to endorse or promote products
12 * derived from this software without specific prior written permission.
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 FOR
18 * 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: releng/6.0/sys/amd64/amd64/busdma_machdep.c 143450 2005-03-12 07:05:59Z scottl $");
29
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/malloc.h>
33 #include <sys/bus.h>
34 #include <sys/interrupt.h>
35 #include <sys/kernel.h>
36 #include <sys/ktr.h>
37 #include <sys/lock.h>
38 #include <sys/proc.h>
39 #include <sys/mutex.h>
40 #include <sys/mbuf.h>
41 #include <sys/uio.h>
42 #include <sys/sysctl.h>
43
44 #include <vm/vm.h>
45 #include <vm/vm_page.h>
46 #include <vm/vm_map.h>
47
48 #include <machine/atomic.h>
49 #include <machine/bus.h>
50 #include <machine/md_var.h>
51
52 #define MAX_BPAGES 512
53
54 struct bounce_zone;
55
56 struct bus_dma_tag {
57 bus_dma_tag_t parent;
58 bus_size_t alignment;
59 bus_size_t boundary;
60 bus_addr_t lowaddr;
61 bus_addr_t highaddr;
62 bus_dma_filter_t *filter;
63 void *filterarg;
64 bus_size_t maxsize;
65 u_int nsegments;
66 bus_size_t maxsegsz;
67 int flags;
68 int ref_count;
69 int map_count;
70 bus_dma_lock_t *lockfunc;
71 void *lockfuncarg;
72 bus_dma_segment_t *segments;
73 struct bounce_zone *bounce_zone;
74 };
75
76 struct bounce_page {
77 vm_offset_t vaddr; /* kva of bounce buffer */
78 bus_addr_t busaddr; /* Physical address */
79 vm_offset_t datavaddr; /* kva of client data */
80 bus_size_t datacount; /* client data count */
81 STAILQ_ENTRY(bounce_page) links;
82 };
83
84 int busdma_swi_pending;
85
86 struct bounce_zone {
87 STAILQ_ENTRY(bounce_zone) links;
88 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
89 int total_bpages;
90 int free_bpages;
91 int reserved_bpages;
92 int active_bpages;
93 int total_bounced;
94 int total_deferred;
95 bus_size_t alignment;
96 bus_size_t boundary;
97 bus_addr_t lowaddr;
98 char zoneid[8];
99 char lowaddrid[20];
100 struct sysctl_ctx_list sysctl_tree;
101 struct sysctl_oid *sysctl_tree_top;
102 };
103
104 static struct mtx bounce_lock;
105 static int total_bpages;
106 static int busdma_zonecount;
107 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
108
109 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
110 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
111 "Total bounce pages");
112
113 struct bus_dmamap {
114 struct bp_list bpages;
115 int pagesneeded;
116 int pagesreserved;
117 bus_dma_tag_t dmat;
118 void *buf; /* unmapped buffer pointer */
119 bus_size_t buflen; /* unmapped buffer length */
120 bus_dmamap_callback_t *callback;
121 void *callback_arg;
122 STAILQ_ENTRY(bus_dmamap) links;
123 };
124
125 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
126 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
127 static struct bus_dmamap nobounce_dmamap;
128
129 static void init_bounce_pages(void *dummy);
130 static int alloc_bounce_zone(bus_dma_tag_t dmat);
131 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
132 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
133 int commit);
134 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
135 vm_offset_t vaddr, bus_size_t size);
136 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
137 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
138
139 /*
140 * Return true if a match is made.
141 *
142 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'.
143 *
144 * If paddr is within the bounds of the dma tag then call the filter callback
145 * to check for a match, if there is no filter callback then assume a match.
146 */
147 static __inline int
148 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
149 {
150 int retval;
151
152 retval = 0;
153
154 do {
155 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr)
156 || ((paddr & (dmat->alignment - 1)) != 0))
157 && (dmat->filter == NULL
158 || (*dmat->filter)(dmat->filterarg, paddr) != 0))
159 retval = 1;
160
161 dmat = dmat->parent;
162 } while (retval == 0 && dmat != NULL);
163 return (retval);
164 }
165
166 /*
167 * Convenience function for manipulating driver locks from busdma (during
168 * busdma_swi, for example). Drivers that don't provide their own locks
169 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own
170 * non-mutex locking scheme don't have to use this at all.
171 */
172 void
173 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
174 {
175 struct mtx *dmtx;
176
177 dmtx = (struct mtx *)arg;
178 switch (op) {
179 case BUS_DMA_LOCK:
180 mtx_lock(dmtx);
181 break;
182 case BUS_DMA_UNLOCK:
183 mtx_unlock(dmtx);
184 break;
185 default:
186 panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
187 }
188 }
189
190 /*
191 * dflt_lock should never get called. It gets put into the dma tag when
192 * lockfunc == NULL, which is only valid if the maps that are associated
193 * with the tag are meant to never be defered.
194 * XXX Should have a way to identify which driver is responsible here.
195 */
196 static void
197 dflt_lock(void *arg, bus_dma_lock_op_t op)
198 {
199 panic("driver error: busdma dflt_lock called");
200 }
201
202 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
203 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
204 /*
205 * Allocate a device specific dma_tag.
206 */
207 int
208 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
209 bus_size_t boundary, bus_addr_t lowaddr,
210 bus_addr_t highaddr, bus_dma_filter_t *filter,
211 void *filterarg, bus_size_t maxsize, int nsegments,
212 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
213 void *lockfuncarg, bus_dma_tag_t *dmat)
214 {
215 bus_dma_tag_t newtag;
216 int error = 0;
217
218 /* Basic sanity checking */
219 if (boundary != 0 && boundary < maxsegsz)
220 maxsegsz = boundary;
221
222 /* Return a NULL tag on failure */
223 *dmat = NULL;
224
225 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF,
226 M_ZERO | M_NOWAIT);
227 if (newtag == NULL) {
228 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
229 __func__, newtag, 0, error);
230 return (ENOMEM);
231 }
232
233 newtag->parent = parent;
234 newtag->alignment = alignment;
235 newtag->boundary = boundary;
236 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
237 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) +
238 (PAGE_SIZE - 1);
239 newtag->filter = filter;
240 newtag->filterarg = filterarg;
241 newtag->maxsize = maxsize;
242 newtag->nsegments = nsegments;
243 newtag->maxsegsz = maxsegsz;
244 newtag->flags = flags;
245 newtag->ref_count = 1; /* Count ourself */
246 newtag->map_count = 0;
247 if (lockfunc != NULL) {
248 newtag->lockfunc = lockfunc;
249 newtag->lockfuncarg = lockfuncarg;
250 } else {
251 newtag->lockfunc = dflt_lock;
252 newtag->lockfuncarg = NULL;
253 }
254 newtag->segments = NULL;
255
256 /* Take into account any restrictions imposed by our parent tag */
257 if (parent != NULL) {
258 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
259 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
260 if (newtag->boundary == 0)
261 newtag->boundary = parent->boundary;
262 else if (parent->boundary != 0)
263 newtag->boundary = MIN(parent->boundary,
264 newtag->boundary);
265 if (newtag->filter == NULL) {
266 /*
267 * Short circuit looking at our parent directly
268 * since we have encapsulated all of its information
269 */
270 newtag->filter = parent->filter;
271 newtag->filterarg = parent->filterarg;
272 newtag->parent = parent->parent;
273 }
274 if (newtag->parent != NULL)
275 atomic_add_int(&parent->ref_count, 1);
276 }
277
278 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem)
279 || newtag->alignment > 1)
280 newtag->flags |= BUS_DMA_COULD_BOUNCE;
281
282 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
283 (flags & BUS_DMA_ALLOCNOW) != 0) {
284 struct bounce_zone *bz;
285
286 /* Must bounce */
287
288 if ((error = alloc_bounce_zone(newtag)) != 0)
289 return (error);
290 bz = newtag->bounce_zone;
291
292 if (ptoa(bz->total_bpages) < maxsize) {
293 int pages;
294
295 pages = atop(maxsize) - bz->total_bpages;
296
297 /* Add pages to our bounce pool */
298 if (alloc_bounce_pages(newtag, pages) < pages)
299 error = ENOMEM;
300 }
301 /* Performed initial allocation */
302 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
303 }
304
305 if (error != 0) {
306 free(newtag, M_DEVBUF);
307 } else {
308 *dmat = newtag;
309 }
310 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
311 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
312 return (error);
313 }
314
315 int
316 bus_dma_tag_destroy(bus_dma_tag_t dmat)
317 {
318 bus_dma_tag_t dmat_copy;
319 int error;
320
321 error = 0;
322 dmat_copy = dmat;
323
324 if (dmat != NULL) {
325
326 if (dmat->map_count != 0) {
327 error = EBUSY;
328 goto out;
329 }
330
331 while (dmat != NULL) {
332 bus_dma_tag_t parent;
333
334 parent = dmat->parent;
335 atomic_subtract_int(&dmat->ref_count, 1);
336 if (dmat->ref_count == 0) {
337 if (dmat->segments != NULL)
338 free(dmat->segments, M_DEVBUF);
339 free(dmat, M_DEVBUF);
340 /*
341 * Last reference count, so
342 * release our reference
343 * count on our parent.
344 */
345 dmat = parent;
346 } else
347 dmat = NULL;
348 }
349 }
350 out:
351 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
352 return (error);
353 }
354
355 /*
356 * Allocate a handle for mapping from kva/uva/physical
357 * address space into bus device space.
358 */
359 int
360 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
361 {
362 int error;
363
364 error = 0;
365
366 if (dmat->segments == NULL) {
367 dmat->segments = (bus_dma_segment_t *)malloc(
368 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
369 M_NOWAIT);
370 if (dmat->segments == NULL) {
371 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
372 __func__, dmat, ENOMEM);
373 return (ENOMEM);
374 }
375 }
376
377 /*
378 * Bouncing might be required if the driver asks for an active
379 * exclusion region, a data alignment that is stricter than 1, and/or
380 * an active address boundary.
381 */
382 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
383
384 /* Must bounce */
385 struct bounce_zone *bz;
386 int maxpages;
387
388 if (dmat->bounce_zone == NULL) {
389 if ((error = alloc_bounce_zone(dmat)) != 0)
390 return (error);
391 }
392 bz = dmat->bounce_zone;
393
394 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
395 M_NOWAIT | M_ZERO);
396 if (*mapp == NULL) {
397 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
398 __func__, dmat, ENOMEM);
399 return (ENOMEM);
400 }
401
402 /* Initialize the new map */
403 STAILQ_INIT(&((*mapp)->bpages));
404
405 /*
406 * Attempt to add pages to our pool on a per-instance
407 * basis up to a sane limit.
408 */
409 if (dmat->alignment > 1)
410 maxpages = MAX_BPAGES;
411 else
412 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
413 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
414 || (dmat->map_count > 0 && bz->total_bpages < maxpages)) {
415 int pages;
416
417 pages = MAX(atop(dmat->maxsize), 1);
418 pages = MIN(maxpages - bz->total_bpages, pages);
419 pages = MAX(pages, 1);
420 if (alloc_bounce_pages(dmat, pages) < pages)
421 error = ENOMEM;
422
423 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
424 if (error == 0)
425 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
426 } else {
427 error = 0;
428 }
429 }
430 } else {
431 *mapp = NULL;
432 }
433 if (error == 0)
434 dmat->map_count++;
435 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
436 __func__, dmat, dmat->flags, error);
437 return (error);
438 }
439
440 /*
441 * Destroy a handle for mapping from kva/uva/physical
442 * address space into bus device space.
443 */
444 int
445 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
446 {
447 if (map != NULL && map != &nobounce_dmamap) {
448 if (STAILQ_FIRST(&map->bpages) != NULL) {
449 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
450 __func__, dmat, EBUSY);
451 return (EBUSY);
452 }
453 free(map, M_DEVBUF);
454 }
455 dmat->map_count--;
456 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
457 return (0);
458 }
459
460
461 /*
462 * Allocate a piece of memory that can be efficiently mapped into
463 * bus device space based on the constraints lited in the dma tag.
464 * A dmamap to for use with dmamap_load is also allocated.
465 */
466 int
467 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
468 bus_dmamap_t *mapp)
469 {
470 int mflags;
471
472 if (flags & BUS_DMA_NOWAIT)
473 mflags = M_NOWAIT;
474 else
475 mflags = M_WAITOK;
476 if (flags & BUS_DMA_ZERO)
477 mflags |= M_ZERO;
478
479 /* If we succeed, no mapping/bouncing will be required */
480 *mapp = NULL;
481
482 if (dmat->segments == NULL) {
483 dmat->segments = (bus_dma_segment_t *)malloc(
484 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
485 M_NOWAIT);
486 if (dmat->segments == NULL) {
487 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
488 __func__, dmat, dmat->flags, ENOMEM);
489 return (ENOMEM);
490 }
491 }
492
493 if ((dmat->maxsize <= PAGE_SIZE) &&
494 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) {
495 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
496 } else {
497 /*
498 * XXX Use Contigmalloc until it is merged into this facility
499 * and handles multi-seg allocations. Nobody is doing
500 * multi-seg allocations yet though.
501 * XXX Certain AGP hardware does.
502 */
503 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
504 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
505 dmat->boundary);
506 }
507 if (*vaddr == NULL) {
508 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
509 __func__, dmat, dmat->flags, ENOMEM);
510 return (ENOMEM);
511 }
512 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
513 __func__, dmat, dmat->flags, ENOMEM);
514 return (0);
515 }
516
517 /*
518 * Free a piece of memory and it's allociated dmamap, that was allocated
519 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
520 */
521 void
522 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
523 {
524 /*
525 * dmamem does not need to be bounced, so the map should be
526 * NULL
527 */
528 if (map != NULL)
529 panic("bus_dmamem_free: Invalid map freed\n");
530 if ((dmat->maxsize <= PAGE_SIZE)
531 && dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem))
532 free(vaddr, M_DEVBUF);
533 else {
534 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
535 }
536 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
537 }
538
539 /*
540 * Utility function to load a linear buffer. lastaddrp holds state
541 * between invocations (for multiple-buffer loads). segp contains
542 * the starting segment on entrace, and the ending segment on exit.
543 * first indicates if this is the first invocation of this function.
544 */
545 static __inline int
546 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
547 bus_dmamap_t map,
548 void *buf, bus_size_t buflen,
549 pmap_t pmap,
550 int flags,
551 bus_addr_t *lastaddrp,
552 bus_dma_segment_t *segs,
553 int *segp,
554 int first)
555 {
556 bus_size_t sgsize;
557 bus_addr_t curaddr, lastaddr, baddr, bmask;
558 vm_offset_t vaddr;
559 bus_addr_t paddr;
560 int needbounce = 0;
561 int seg;
562
563 if (map == NULL)
564 map = &nobounce_dmamap;
565
566 if ((map != &nobounce_dmamap && map->pagesneeded == 0)
567 && ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0)) {
568 vm_offset_t vendaddr;
569
570 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
571 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
572 dmat->boundary, dmat->alignment);
573 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d",
574 map, &nobounce_dmamap, map->pagesneeded);
575 /*
576 * Count the number of bounce pages
577 * needed in order to complete this transfer
578 */
579 vaddr = trunc_page((vm_offset_t)buf);
580 vendaddr = (vm_offset_t)buf + buflen;
581
582 while (vaddr < vendaddr) {
583 paddr = pmap_kextract(vaddr);
584 if (run_filter(dmat, paddr) != 0) {
585 needbounce = 1;
586 map->pagesneeded++;
587 }
588 vaddr += PAGE_SIZE;
589 }
590 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
591 }
592
593 /* Reserve Necessary Bounce Pages */
594 if (map->pagesneeded != 0) {
595 mtx_lock(&bounce_lock);
596 if (flags & BUS_DMA_NOWAIT) {
597 if (reserve_bounce_pages(dmat, map, 0) != 0) {
598 mtx_unlock(&bounce_lock);
599 return (ENOMEM);
600 }
601 } else {
602 if (reserve_bounce_pages(dmat, map, 1) != 0) {
603 /* Queue us for resources */
604 map->dmat = dmat;
605 map->buf = buf;
606 map->buflen = buflen;
607 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
608 map, links);
609 mtx_unlock(&bounce_lock);
610 return (EINPROGRESS);
611 }
612 }
613 mtx_unlock(&bounce_lock);
614 }
615
616 vaddr = (vm_offset_t)buf;
617 lastaddr = *lastaddrp;
618 bmask = ~(dmat->boundary - 1);
619
620 for (seg = *segp; buflen > 0 ; ) {
621 /*
622 * Get the physical address for this segment.
623 */
624 if (pmap)
625 curaddr = pmap_extract(pmap, vaddr);
626 else
627 curaddr = pmap_kextract(vaddr);
628
629 /*
630 * Compute the segment size, and adjust counts.
631 */
632 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK);
633 if (buflen < sgsize)
634 sgsize = buflen;
635
636 /*
637 * Make sure we don't cross any boundaries.
638 */
639 if (dmat->boundary > 0) {
640 baddr = (curaddr + dmat->boundary) & bmask;
641 if (sgsize > (baddr - curaddr))
642 sgsize = (baddr - curaddr);
643 }
644
645 if (map->pagesneeded != 0 && run_filter(dmat, curaddr))
646 curaddr = add_bounce_page(dmat, map, vaddr, sgsize);
647
648 /*
649 * Insert chunk into a segment, coalescing with
650 * previous segment if possible.
651 */
652 if (first) {
653 segs[seg].ds_addr = curaddr;
654 segs[seg].ds_len = sgsize;
655 first = 0;
656 } else {
657 if (needbounce == 0 && curaddr == lastaddr &&
658 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
659 (dmat->boundary == 0 ||
660 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
661 segs[seg].ds_len += sgsize;
662 else {
663 if (++seg >= dmat->nsegments)
664 break;
665 segs[seg].ds_addr = curaddr;
666 segs[seg].ds_len = sgsize;
667 }
668 }
669
670 lastaddr = curaddr + sgsize;
671 vaddr += sgsize;
672 buflen -= sgsize;
673 }
674
675 *segp = seg;
676 *lastaddrp = lastaddr;
677
678 /*
679 * Did we fit?
680 */
681 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
682 }
683
684 /*
685 * Map the buffer buf into bus space using the dmamap map.
686 */
687 int
688 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
689 bus_size_t buflen, bus_dmamap_callback_t *callback,
690 void *callback_arg, int flags)
691 {
692 bus_addr_t lastaddr = 0;
693 int error, nsegs = 0;
694
695 if (map != NULL) {
696 flags |= BUS_DMA_WAITOK;
697 map->callback = callback;
698 map->callback_arg = callback_arg;
699 }
700
701 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags,
702 &lastaddr, dmat->segments, &nsegs, 1);
703
704 if (error == EINPROGRESS) {
705 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
706 __func__, dmat, dmat->flags, error);
707 return (error);
708 }
709
710 if (error)
711 (*callback)(callback_arg, dmat->segments, 0, error);
712 else
713 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0);
714
715 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error 0 nsegs %d",
716 __func__, dmat, dmat->flags, nsegs + 1);
717 return (0);
718 }
719
720
721 /*
722 * Like _bus_dmamap_load(), but for mbufs.
723 */
724 int
725 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
726 struct mbuf *m0,
727 bus_dmamap_callback2_t *callback, void *callback_arg,
728 int flags)
729 {
730 int nsegs, error;
731
732 M_ASSERTPKTHDR(m0);
733
734 flags |= BUS_DMA_NOWAIT;
735 nsegs = 0;
736 error = 0;
737 if (m0->m_pkthdr.len <= dmat->maxsize) {
738 int first = 1;
739 bus_addr_t lastaddr = 0;
740 struct mbuf *m;
741
742 for (m = m0; m != NULL && error == 0; m = m->m_next) {
743 if (m->m_len > 0) {
744 error = _bus_dmamap_load_buffer(dmat, map,
745 m->m_data, m->m_len,
746 NULL, flags, &lastaddr,
747 dmat->segments, &nsegs, first);
748 first = 0;
749 }
750 }
751 } else {
752 error = EINVAL;
753 }
754
755 if (error) {
756 /* force "no valid mappings" in callback */
757 (*callback)(callback_arg, dmat->segments, 0, 0, error);
758 } else {
759 (*callback)(callback_arg, dmat->segments,
760 nsegs+1, m0->m_pkthdr.len, error);
761 }
762 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
763 __func__, dmat, dmat->flags, error, nsegs + 1);
764 return (error);
765 }
766
767 int
768 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map,
769 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs,
770 int flags)
771 {
772 int error;
773
774 M_ASSERTPKTHDR(m0);
775
776 flags |= BUS_DMA_NOWAIT;
777 *nsegs = 0;
778 error = 0;
779 if (m0->m_pkthdr.len <= dmat->maxsize) {
780 int first = 1;
781 bus_addr_t lastaddr = 0;
782 struct mbuf *m;
783
784 for (m = m0; m != NULL && error == 0; m = m->m_next) {
785 if (m->m_len > 0) {
786 error = _bus_dmamap_load_buffer(dmat, map,
787 m->m_data, m->m_len,
788 NULL, flags, &lastaddr,
789 segs, nsegs, first);
790 first = 0;
791 }
792 }
793 } else {
794 error = EINVAL;
795 }
796
797 /* XXX FIXME: Having to increment nsegs is really annoying */
798 ++*nsegs;
799 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
800 __func__, dmat, dmat->flags, error, *nsegs);
801 return (error);
802 }
803
804 /*
805 * Like _bus_dmamap_load(), but for uios.
806 */
807 int
808 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
809 struct uio *uio,
810 bus_dmamap_callback2_t *callback, void *callback_arg,
811 int flags)
812 {
813 bus_addr_t lastaddr;
814 int nsegs, error, first, i;
815 bus_size_t resid;
816 struct iovec *iov;
817 pmap_t pmap;
818
819 flags |= BUS_DMA_NOWAIT;
820 resid = uio->uio_resid;
821 iov = uio->uio_iov;
822
823 if (uio->uio_segflg == UIO_USERSPACE) {
824 KASSERT(uio->uio_td != NULL,
825 ("bus_dmamap_load_uio: USERSPACE but no proc"));
826 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace);
827 } else
828 pmap = NULL;
829
830 nsegs = 0;
831 error = 0;
832 first = 1;
833 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
834 /*
835 * Now at the first iovec to load. Load each iovec
836 * until we have exhausted the residual count.
837 */
838 bus_size_t minlen =
839 resid < iov[i].iov_len ? resid : iov[i].iov_len;
840 caddr_t addr = (caddr_t) iov[i].iov_base;
841
842 if (minlen > 0) {
843 error = _bus_dmamap_load_buffer(dmat, map,
844 addr, minlen, pmap, flags, &lastaddr,
845 dmat->segments, &nsegs, first);
846 first = 0;
847
848 resid -= minlen;
849 }
850 }
851
852 if (error) {
853 /* force "no valid mappings" in callback */
854 (*callback)(callback_arg, dmat->segments, 0, 0, error);
855 } else {
856 (*callback)(callback_arg, dmat->segments,
857 nsegs+1, uio->uio_resid, error);
858 }
859 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
860 __func__, dmat, dmat->flags, error, nsegs + 1);
861 return (error);
862 }
863
864 /*
865 * Release the mapping held by map.
866 */
867 void
868 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
869 {
870 struct bounce_page *bpage;
871
872 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
873 STAILQ_REMOVE_HEAD(&map->bpages, links);
874 free_bounce_page(dmat, bpage);
875 }
876 }
877
878 void
879 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
880 {
881 struct bounce_page *bpage;
882
883 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
884 /*
885 * Handle data bouncing. We might also
886 * want to add support for invalidating
887 * the caches on broken hardware
888 */
889 dmat->bounce_zone->total_bounced++;
890 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
891 "performing bounce", __func__, op, dmat, dmat->flags);
892
893 if (op & BUS_DMASYNC_PREWRITE) {
894 while (bpage != NULL) {
895 bcopy((void *)bpage->datavaddr,
896 (void *)bpage->vaddr,
897 bpage->datacount);
898 bpage = STAILQ_NEXT(bpage, links);
899 }
900 }
901
902 if (op & BUS_DMASYNC_POSTREAD) {
903 while (bpage != NULL) {
904 bcopy((void *)bpage->vaddr,
905 (void *)bpage->datavaddr,
906 bpage->datacount);
907 bpage = STAILQ_NEXT(bpage, links);
908 }
909 }
910 }
911 }
912
913 static void
914 init_bounce_pages(void *dummy __unused)
915 {
916
917 total_bpages = 0;
918 STAILQ_INIT(&bounce_zone_list);
919 STAILQ_INIT(&bounce_map_waitinglist);
920 STAILQ_INIT(&bounce_map_callbacklist);
921 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
922 }
923 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
924
925 static struct sysctl_ctx_list *
926 busdma_sysctl_tree(struct bounce_zone *bz)
927 {
928 return (&bz->sysctl_tree);
929 }
930
931 static struct sysctl_oid *
932 busdma_sysctl_tree_top(struct bounce_zone *bz)
933 {
934 return (bz->sysctl_tree_top);
935 }
936
937 static int
938 alloc_bounce_zone(bus_dma_tag_t dmat)
939 {
940 struct bounce_zone *bz;
941
942 /* Check to see if we already have a suitable zone */
943 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
944 if ((dmat->alignment <= bz->alignment)
945 && (dmat->boundary <= bz->boundary)
946 && (dmat->lowaddr >= bz->lowaddr)) {
947 dmat->bounce_zone = bz;
948 return (0);
949 }
950 }
951
952 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
953 M_NOWAIT | M_ZERO)) == NULL)
954 return (ENOMEM);
955
956 STAILQ_INIT(&bz->bounce_page_list);
957 bz->free_bpages = 0;
958 bz->reserved_bpages = 0;
959 bz->active_bpages = 0;
960 bz->lowaddr = dmat->lowaddr;
961 bz->alignment = dmat->alignment;
962 bz->boundary = dmat->boundary;
963 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
964 busdma_zonecount++;
965 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
966 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
967 dmat->bounce_zone = bz;
968
969 sysctl_ctx_init(&bz->sysctl_tree);
970 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
971 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
972 CTLFLAG_RD, 0, "");
973 if (bz->sysctl_tree_top == NULL) {
974 sysctl_ctx_free(&bz->sysctl_tree);
975 return (0); /* XXX error code? */
976 }
977
978 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
979 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
980 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
981 "Totoal bounce pages");
982 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
983 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
984 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
985 "Free bounce pages");
986 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
987 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
988 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
989 "Reserved bounce pages");
990 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
991 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
992 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
993 "Active bounce pages");
994 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
995 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
996 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
997 "Total bounce requests");
998 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
999 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1000 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1001 "Total bounce requests that were deferred");
1002 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1003 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1004 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1005 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1006 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1007 "alignment", CTLFLAG_RD, &bz->alignment, 0, "");
1008 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1009 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1010 "boundary", CTLFLAG_RD, &bz->boundary, 0, "");
1011
1012 return (0);
1013 }
1014
1015 static int
1016 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1017 {
1018 struct bounce_zone *bz;
1019 int count;
1020
1021 bz = dmat->bounce_zone;
1022 count = 0;
1023 while (numpages > 0) {
1024 struct bounce_page *bpage;
1025
1026 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1027 M_NOWAIT | M_ZERO);
1028
1029 if (bpage == NULL)
1030 break;
1031 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1032 M_NOWAIT, 0ul,
1033 bz->lowaddr,
1034 PAGE_SIZE,
1035 bz->boundary);
1036 if (bpage->vaddr == 0) {
1037 free(bpage, M_DEVBUF);
1038 break;
1039 }
1040 bpage->busaddr = pmap_kextract(bpage->vaddr);
1041 mtx_lock(&bounce_lock);
1042 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1043 total_bpages++;
1044 bz->total_bpages++;
1045 bz->free_bpages++;
1046 mtx_unlock(&bounce_lock);
1047 count++;
1048 numpages--;
1049 }
1050 return (count);
1051 }
1052
1053 static int
1054 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1055 {
1056 struct bounce_zone *bz;
1057 int pages;
1058
1059 mtx_assert(&bounce_lock, MA_OWNED);
1060 bz = dmat->bounce_zone;
1061 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1062 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1063 return (map->pagesneeded - (map->pagesreserved + pages));
1064 bz->free_bpages -= pages;
1065 bz->reserved_bpages += pages;
1066 map->pagesreserved += pages;
1067 pages = map->pagesneeded - map->pagesreserved;
1068
1069 return (pages);
1070 }
1071
1072 static bus_addr_t
1073 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1074 bus_size_t size)
1075 {
1076 struct bounce_zone *bz;
1077 struct bounce_page *bpage;
1078
1079 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1080 KASSERT(map != NULL && map != &nobounce_dmamap,
1081 ("add_bounce_page: bad map %p", map));
1082
1083 bz = dmat->bounce_zone;
1084 if (map->pagesneeded == 0)
1085 panic("add_bounce_page: map doesn't need any pages");
1086 map->pagesneeded--;
1087
1088 if (map->pagesreserved == 0)
1089 panic("add_bounce_page: map doesn't need any pages");
1090 map->pagesreserved--;
1091
1092 mtx_lock(&bounce_lock);
1093 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1094 if (bpage == NULL)
1095 panic("add_bounce_page: free page list is empty");
1096
1097 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1098 bz->reserved_bpages--;
1099 bz->active_bpages++;
1100 mtx_unlock(&bounce_lock);
1101
1102 bpage->datavaddr = vaddr;
1103 bpage->datacount = size;
1104 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1105 return (bpage->busaddr);
1106 }
1107
1108 static void
1109 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1110 {
1111 struct bus_dmamap *map;
1112 struct bounce_zone *bz;
1113
1114 bz = dmat->bounce_zone;
1115 bpage->datavaddr = 0;
1116 bpage->datacount = 0;
1117
1118 mtx_lock(&bounce_lock);
1119 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1120 bz->free_bpages++;
1121 bz->active_bpages--;
1122 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1123 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1124 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1125 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1126 map, links);
1127 busdma_swi_pending = 1;
1128 bz->total_deferred++;
1129 swi_sched(vm_ih, 0);
1130 }
1131 }
1132 mtx_unlock(&bounce_lock);
1133 }
1134
1135 void
1136 busdma_swi(void)
1137 {
1138 bus_dma_tag_t dmat;
1139 struct bus_dmamap *map;
1140
1141 mtx_lock(&bounce_lock);
1142 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1143 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1144 mtx_unlock(&bounce_lock);
1145 dmat = map->dmat;
1146 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1147 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
1148 map->callback, map->callback_arg, /*flags*/0);
1149 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1150 mtx_lock(&bounce_lock);
1151 }
1152 mtx_unlock(&bounce_lock);
1153 }
Cache object: 70cf33b6d75e2529242e5d97f38ade92
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