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 * $FreeBSD$
27 */
28
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/malloc.h>
32 #include <sys/mbuf.h>
33 #include <sys/uio.h>
34
35 #include <vm/vm.h>
36 #include <vm/vm_page.h>
37
38 /* XXX needed for to access pmap to convert per-proc virtual to physical */
39 #include <sys/proc.h>
40 #include <sys/lock.h>
41 #include <vm/vm_map.h>
42
43 #include <machine/bus.h>
44 #include <machine/md_var.h>
45
46 #define MAX(a,b) (((a) > (b)) ? (a) : (b))
47 #define MIN(a,b) (((a) < (b)) ? (a) : (b))
48 #define MAX_BPAGES 128
49
50 struct bus_dma_tag {
51 bus_dma_tag_t parent;
52 bus_size_t alignment;
53 bus_size_t boundary;
54 bus_addr_t lowaddr;
55 bus_addr_t highaddr;
56 bus_dma_filter_t *filter;
57 void *filterarg;
58 bus_size_t maxsize;
59 u_int nsegments;
60 bus_size_t maxsegsz;
61 int flags;
62 int ref_count;
63 int map_count;
64 };
65
66 struct bounce_page {
67 vm_offset_t vaddr; /* kva of bounce buffer */
68 bus_addr_t busaddr; /* Physical address */
69 vm_offset_t datavaddr; /* kva of client data */
70 bus_size_t datacount; /* client data count */
71 STAILQ_ENTRY(bounce_page) links;
72 };
73
74 int busdma_swi_pending;
75
76 static STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
77 static int free_bpages;
78 static int reserved_bpages;
79 static int active_bpages;
80 static int total_bpages;
81 static bus_addr_t bounce_lowaddr = BUS_SPACE_MAXADDR;
82
83 struct bus_dmamap {
84 struct bp_list bpages;
85 int pagesneeded;
86 int pagesreserved;
87 bus_dma_tag_t dmat;
88 void *buf; /* unmapped buffer pointer */
89 bus_size_t buflen; /* unmapped buffer length */
90 bus_dmamap_callback_t *callback;
91 void *callback_arg;
92 STAILQ_ENTRY(bus_dmamap) links;
93 };
94
95 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
96 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
97 static struct bus_dmamap nobounce_dmamap;
98
99 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
100 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map);
101 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
102 vm_offset_t vaddr, bus_size_t size);
103 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
104 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
105
106 static __inline int
107 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
108 {
109 int retval;
110
111 retval = 0;
112 do {
113 if (paddr > dmat->lowaddr
114 && paddr <= dmat->highaddr
115 && (dmat->filter == NULL
116 || (*dmat->filter)(dmat->filterarg, paddr) != 0))
117 retval = 1;
118
119 dmat = dmat->parent;
120 } while (retval == 0 && dmat != NULL);
121 return (retval);
122 }
123
124 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
125 /*
126 * Allocate a device specific dma_tag.
127 */
128 int
129 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
130 bus_size_t boundary, bus_addr_t lowaddr,
131 bus_addr_t highaddr, bus_dma_filter_t *filter,
132 void *filterarg, bus_size_t maxsize, int nsegments,
133 bus_size_t maxsegsz, int flags, bus_dma_tag_t *dmat)
134 {
135 bus_dma_tag_t newtag;
136 int error = 0;
137
138 /* Return a NULL tag on failure */
139 *dmat = NULL;
140
141 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, M_NOWAIT);
142 if (newtag == NULL)
143 return (ENOMEM);
144
145 newtag->parent = parent;
146 newtag->alignment = alignment;
147 newtag->boundary = boundary;
148 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
149 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
150 newtag->filter = filter;
151 newtag->filterarg = filterarg;
152 newtag->maxsize = maxsize;
153 newtag->nsegments = nsegments;
154 newtag->maxsegsz = maxsegsz;
155 newtag->flags = flags;
156 newtag->ref_count = 1; /* Count ourself */
157 newtag->map_count = 0;
158
159 /* Take into account any restrictions imposed by our parent tag */
160 if (parent != NULL) {
161 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
162 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
163 /*
164 * XXX Not really correct??? Probably need to honor boundary
165 * all the way up the inheritence chain.
166 */
167 newtag->boundary = MAX(parent->boundary, newtag->boundary);
168 if (newtag->filter == NULL) {
169 /*
170 * Short circuit looking at our parent directly
171 * since we have encapsulated all of its information
172 */
173 newtag->filter = parent->filter;
174 newtag->filterarg = parent->filterarg;
175 newtag->parent = parent->parent;
176 }
177 if (newtag->parent != NULL) {
178 parent->ref_count++;
179 }
180 }
181
182 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) &&
183 (flags & BUS_DMA_ALLOCNOW) != 0) {
184 /* Must bounce */
185
186 if (lowaddr > bounce_lowaddr) {
187 /*
188 * Go through the pool and kill any pages
189 * that don't reside below lowaddr.
190 */
191 panic("bus_dma_tag_create: page reallocation "
192 "not implemented");
193 }
194 if (ptoa(total_bpages) < maxsize) {
195 int pages;
196
197 pages = atop(maxsize) - total_bpages;
198
199 /* Add pages to our bounce pool */
200 if (alloc_bounce_pages(newtag, pages) < pages)
201 error = ENOMEM;
202 }
203 /* Performed initial allocation */
204 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
205 }
206
207 if (error != 0) {
208 free(newtag, M_DEVBUF);
209 } else {
210 *dmat = newtag;
211 }
212 return (error);
213 }
214
215 int
216 bus_dma_tag_destroy(bus_dma_tag_t dmat)
217 {
218 if (dmat != NULL) {
219
220 if (dmat->map_count != 0)
221 return (EBUSY);
222
223 while (dmat != NULL) {
224 bus_dma_tag_t parent;
225
226 parent = dmat->parent;
227 dmat->ref_count--;
228 if (dmat->ref_count == 0) {
229 free(dmat, M_DEVBUF);
230 /*
231 * Last reference count, so
232 * release our reference
233 * count on our parent.
234 */
235 dmat = parent;
236 } else
237 dmat = NULL;
238 }
239 }
240 return (0);
241 }
242
243 /*
244 * Allocate a handle for mapping from kva/uva/physical
245 * address space into bus device space.
246 */
247 int
248 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
249 {
250 int error;
251
252 error = 0;
253
254 if (dmat->lowaddr < ptoa((vm_paddr_t)Maxmem)) {
255 /* Must bounce */
256 int maxpages;
257
258 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
259 M_NOWAIT);
260 if (*mapp == NULL) {
261 return (ENOMEM);
262 } else {
263 /* Initialize the new map */
264 bzero(*mapp, sizeof(**mapp));
265 STAILQ_INIT(&((*mapp)->bpages));
266 }
267 /*
268 * Attempt to add pages to our pool on a per-instance
269 * basis up to a sane limit.
270 */
271 maxpages = MIN(MAX_BPAGES, Maxmem - atop(dmat->lowaddr));
272 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
273 || (dmat->map_count > 0
274 && total_bpages < maxpages)) {
275 int pages;
276
277 if (dmat->lowaddr > bounce_lowaddr) {
278 /*
279 * Go through the pool and kill any pages
280 * that don't reside below lowaddr.
281 */
282 panic("bus_dmamap_create: page reallocation "
283 "not implemented");
284 }
285 pages = atop(dmat->maxsize);
286 pages = MIN(maxpages - total_bpages, pages);
287 if (alloc_bounce_pages(dmat, pages) < pages)
288 error = ENOMEM;
289
290 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
291 if (error == 0)
292 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
293 } else {
294 error = 0;
295 }
296 }
297 } else {
298 *mapp = NULL;
299 }
300 if (error == 0)
301 dmat->map_count++;
302 return (error);
303 }
304
305 /*
306 * Destroy a handle for mapping from kva/uva/physical
307 * address space into bus device space.
308 */
309 int
310 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
311 {
312 if (map != NULL) {
313 if (STAILQ_FIRST(&map->bpages) != NULL)
314 return (EBUSY);
315 free(map, M_DEVBUF);
316 }
317 dmat->map_count--;
318 return (0);
319 }
320
321
322 /*
323 * Allocate a piece of memory that can be efficiently mapped into
324 * bus device space based on the constraints lited in the dma tag.
325 * A dmamap to for use with dmamap_load is also allocated.
326 */
327 int
328 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
329 bus_dmamap_t *mapp)
330 {
331 int mflags;
332
333 if (flags & BUS_DMA_NOWAIT)
334 mflags = M_NOWAIT;
335 else
336 mflags = M_WAITOK;
337 if (flags & BUS_DMA_ZERO)
338 mflags |= M_ZERO;
339
340 /* If we succeed, no mapping/bouncing will be required */
341 *mapp = NULL;
342
343 if ((dmat->maxsize <= PAGE_SIZE) &&
344 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) {
345 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
346 } else {
347 /*
348 * XXX Use Contigmalloc until it is merged into this facility
349 * and handles multi-seg allocations. Nobody is doing
350 * multi-seg allocations yet though.
351 */
352 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
353 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
354 dmat->boundary);
355 }
356 if (*vaddr == NULL)
357 return (ENOMEM);
358 return (0);
359 }
360
361 /*
362 * Free a piece of memory and it's allociated dmamap, that was allocated
363 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
364 */
365 void
366 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
367 {
368 /*
369 * dmamem does not need to be bounced, so the map should be
370 * NULL
371 */
372 if (map != NULL)
373 panic("bus_dmamem_free: Invalid map freed\n");
374 if ((dmat->maxsize <= PAGE_SIZE) &&
375 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem))
376 free(vaddr, M_DEVBUF);
377 else
378 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
379 }
380
381 #define BUS_DMAMAP_NSEGS ((BUS_SPACE_MAXSIZE / PAGE_SIZE) + 1)
382
383 /*
384 * Map the buffer buf into bus space using the dmamap map.
385 */
386 int
387 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
388 bus_size_t buflen, bus_dmamap_callback_t *callback,
389 void *callback_arg, int flags)
390 {
391 vm_offset_t vaddr;
392 vm_paddr_t paddr;
393 #ifdef __GNUC__
394 bus_dma_segment_t dm_segments[dmat->nsegments];
395 #else
396 bus_dma_segment_t dm_segments[BUS_DMAMAP_NSEGS];
397 #endif
398 bus_dma_segment_t *sg;
399 int seg;
400 int error;
401 vm_paddr_t nextpaddr;
402
403 if (map == NULL)
404 map = &nobounce_dmamap;
405
406 error = 0;
407 /*
408 * If we are being called during a callback, pagesneeded will
409 * be non-zero, so we can avoid doing the work twice.
410 */
411 if (dmat->lowaddr < ptoa((vm_paddr_t)Maxmem) &&
412 map->pagesneeded == 0) {
413 vm_offset_t vendaddr;
414
415 /*
416 * Count the number of bounce pages
417 * needed in order to complete this transfer
418 */
419 vaddr = trunc_page((vm_offset_t)buf);
420 vendaddr = (vm_offset_t)buf + buflen;
421
422 while (vaddr < vendaddr) {
423 paddr = pmap_kextract(vaddr);
424 if (run_filter(dmat, paddr) != 0) {
425
426 map->pagesneeded++;
427 }
428 vaddr += PAGE_SIZE;
429 }
430 }
431
432 /* Reserve Necessary Bounce Pages */
433 if (map->pagesneeded != 0) {
434 int s;
435
436 s = splhigh();
437 if (reserve_bounce_pages(dmat, map) != 0) {
438
439 /* Queue us for resources */
440 map->dmat = dmat;
441 map->buf = buf;
442 map->buflen = buflen;
443 map->callback = callback;
444 map->callback_arg = callback_arg;
445
446 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, map, links);
447 splx(s);
448
449 return (EINPROGRESS);
450 }
451 splx(s);
452 }
453
454 vaddr = (vm_offset_t)buf;
455 sg = &dm_segments[0];
456 seg = 1;
457 sg->ds_len = 0;
458
459 nextpaddr = 0;
460 do {
461 bus_size_t size;
462
463 paddr = pmap_kextract(vaddr);
464 size = PAGE_SIZE - (paddr & PAGE_MASK);
465 if (size > buflen)
466 size = buflen;
467
468 if (map->pagesneeded != 0 && run_filter(dmat, paddr)) {
469 paddr = add_bounce_page(dmat, map, vaddr, size);
470 }
471
472 if (sg->ds_len == 0) {
473 sg->ds_addr = paddr;
474 sg->ds_len = size;
475 } else if (paddr == nextpaddr) {
476 sg->ds_len += size;
477 } else {
478 /* Go to the next segment */
479 sg++;
480 seg++;
481 if (seg > dmat->nsegments)
482 break;
483 sg->ds_addr = paddr;
484 sg->ds_len = size;
485 }
486 vaddr += size;
487 nextpaddr = paddr + size;
488 buflen -= size;
489
490 } while (buflen > 0);
491
492 if (buflen != 0) {
493 printf("bus_dmamap_load: Too many segs! buf_len = 0x%lx\n",
494 (u_long)buflen);
495 error = EFBIG;
496 }
497
498 (*callback)(callback_arg, dm_segments, seg, error);
499
500 return (0);
501 }
502
503 /*
504 * Utility function to load a linear buffer. lastaddrp holds state
505 * between invocations (for multiple-buffer loads). segp contains
506 * the starting segment on entrace, and the ending segment on exit.
507 * first indicates if this is the first invocation of this function.
508 */
509 static int
510 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
511 bus_dma_segment_t segs[],
512 void *buf, bus_size_t buflen,
513 struct proc *p,
514 int flags,
515 vm_offset_t *lastaddrp,
516 int *segp,
517 int first)
518 {
519 bus_size_t sgsize;
520 bus_addr_t curaddr, lastaddr, baddr, bmask;
521 vm_offset_t vaddr = (vm_offset_t)buf;
522 int seg;
523 pmap_t pmap;
524
525 if (p != NULL)
526 pmap = vmspace_pmap(p->p_vmspace);
527 else
528 pmap = NULL;
529
530 lastaddr = *lastaddrp;
531 bmask = ~(dmat->boundary - 1);
532
533 for (seg = *segp; buflen > 0 ; ) {
534 /*
535 * Get the physical address for this segment.
536 */
537 if (pmap)
538 curaddr = pmap_extract(pmap, vaddr);
539 else
540 curaddr = pmap_kextract(vaddr);
541
542 /*
543 * Compute the segment size, and adjust counts.
544 */
545 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK);
546 if (buflen < sgsize)
547 sgsize = buflen;
548
549 /*
550 * Make sure we don't cross any boundaries.
551 */
552 if (dmat->boundary > 0) {
553 baddr = (curaddr + dmat->boundary) & bmask;
554 if (sgsize > (baddr - curaddr))
555 sgsize = (baddr - curaddr);
556 }
557
558 /*
559 * Insert chunk into a segment, coalescing with
560 * previous segment if possible.
561 */
562 if (first) {
563 segs[seg].ds_addr = curaddr;
564 segs[seg].ds_len = sgsize;
565 first = 0;
566 } else {
567 if (curaddr == lastaddr &&
568 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
569 (dmat->boundary == 0 ||
570 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
571 segs[seg].ds_len += sgsize;
572 else {
573 if (++seg >= dmat->nsegments)
574 break;
575 segs[seg].ds_addr = curaddr;
576 segs[seg].ds_len = sgsize;
577 }
578 }
579
580 lastaddr = curaddr + sgsize;
581 vaddr += sgsize;
582 buflen -= sgsize;
583 }
584
585 *segp = seg;
586 *lastaddrp = lastaddr;
587
588 /*
589 * Did we fit?
590 */
591 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
592 }
593
594 /*
595 * Like _bus_dmamap_load(), but for mbufs.
596 */
597 int
598 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
599 struct mbuf *m0,
600 bus_dmamap_callback2_t *callback, void *callback_arg,
601 int flags)
602 {
603 #ifdef __GNUC__
604 bus_dma_segment_t dm_segments[dmat->nsegments];
605 #else
606 bus_dma_segment_t dm_segments[BUS_DMAMAP_NSEGS];
607 #endif
608 int nsegs, error;
609
610 KASSERT(dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem) || map != NULL,
611 ("bus_dmamap_load_mbuf: No support for bounce pages!"));
612 KASSERT(m0->m_flags & M_PKTHDR,
613 ("bus_dmamap_load_mbuf: no packet header"));
614
615 nsegs = 0;
616 error = 0;
617 if (m0->m_pkthdr.len <= dmat->maxsize) {
618 int first = 1;
619 vm_offset_t lastaddr = 0;
620 struct mbuf *m;
621
622 for (m = m0; m != NULL && error == 0; m = m->m_next) {
623 error = _bus_dmamap_load_buffer(dmat,
624 dm_segments,
625 m->m_data, m->m_len,
626 NULL, flags, &lastaddr, &nsegs, first);
627 first = 0;
628 }
629 } else {
630 error = EINVAL;
631 }
632
633 if (error) {
634 /* force "no valid mappings" in callback */
635 (*callback)(callback_arg, dm_segments, 0, 0, error);
636 } else {
637 (*callback)(callback_arg, dm_segments,
638 nsegs+1, m0->m_pkthdr.len, error);
639 }
640 return (error);
641 }
642
643 /*
644 * Like _bus_dmamap_load(), but for uios.
645 */
646 int
647 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
648 struct uio *uio,
649 bus_dmamap_callback2_t *callback, void *callback_arg,
650 int flags)
651 {
652 vm_offset_t lastaddr;
653 #ifdef __GNUC__
654 bus_dma_segment_t dm_segments[dmat->nsegments];
655 #else
656 bus_dma_segment_t dm_segments[BUS_DMAMAP_NSEGS];
657 #endif
658 int nsegs, error, first, i;
659 bus_size_t resid;
660 struct iovec *iov;
661 struct proc *p = NULL;
662
663 KASSERT(dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem) || map != NULL,
664 ("bus_dmamap_load_uio: No support for bounce pages!"));
665
666 resid = uio->uio_resid;
667 iov = uio->uio_iov;
668
669 if (uio->uio_segflg == UIO_USERSPACE) {
670 p = uio->uio_procp;
671 KASSERT(p != NULL,
672 ("bus_dmamap_load_uio: USERSPACE but no proc"));
673 }
674
675 nsegs = 0;
676 error = 0;
677 first = 1;
678 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
679 /*
680 * Now at the first iovec to load. Load each iovec
681 * until we have exhausted the residual count.
682 */
683 bus_size_t minlen =
684 resid < iov[i].iov_len ? resid : iov[i].iov_len;
685 caddr_t addr = (caddr_t) iov[i].iov_base;
686
687 error = _bus_dmamap_load_buffer(dmat,
688 dm_segments,
689 addr, minlen,
690 p, flags, &lastaddr, &nsegs, first);
691 first = 0;
692
693 resid -= minlen;
694 }
695
696 if (error) {
697 /* force "no valid mappings" in callback */
698 (*callback)(callback_arg, dm_segments, 0, 0, error);
699 } else {
700 (*callback)(callback_arg, dm_segments,
701 nsegs+1, uio->uio_resid, error);
702 }
703 return (error);
704 }
705
706 /*
707 * Release the mapping held by map.
708 */
709 void
710 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
711 {
712 struct bounce_page *bpage;
713
714 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
715 STAILQ_REMOVE_HEAD(&map->bpages, links);
716 free_bounce_page(dmat, bpage);
717 }
718 }
719
720 void
721 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
722 {
723 struct bounce_page *bpage;
724
725 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
726
727 /*
728 * Handle data bouncing. We might also
729 * want to add support for invalidating
730 * the caches on broken hardware
731 */
732 switch (op) {
733 case BUS_DMASYNC_PREWRITE:
734 while (bpage != NULL) {
735 bcopy((void *)bpage->datavaddr,
736 (void *)bpage->vaddr,
737 bpage->datacount);
738 bpage = STAILQ_NEXT(bpage, links);
739 }
740 break;
741
742 case BUS_DMASYNC_POSTREAD:
743 while (bpage != NULL) {
744 bcopy((void *)bpage->vaddr,
745 (void *)bpage->datavaddr,
746 bpage->datacount);
747 bpage = STAILQ_NEXT(bpage, links);
748 }
749 break;
750 case BUS_DMASYNC_PREREAD:
751 case BUS_DMASYNC_POSTWRITE:
752 /* No-ops */
753 break;
754 }
755 }
756 }
757
758 static int
759 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
760 {
761 int count;
762
763 count = 0;
764 if (total_bpages == 0) {
765 STAILQ_INIT(&bounce_page_list);
766 STAILQ_INIT(&bounce_map_waitinglist);
767 STAILQ_INIT(&bounce_map_callbacklist);
768 }
769
770 while (numpages > 0) {
771 struct bounce_page *bpage;
772 int s;
773
774 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
775 M_NOWAIT);
776
777 if (bpage == NULL)
778 break;
779 bzero(bpage, sizeof(*bpage));
780 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
781 M_NOWAIT, 0ul,
782 dmat->lowaddr,
783 PAGE_SIZE,
784 0);
785 if (bpage->vaddr == NULL) {
786 free(bpage, M_DEVBUF);
787 break;
788 }
789 bpage->busaddr = pmap_kextract(bpage->vaddr);
790 s = splhigh();
791 STAILQ_INSERT_TAIL(&bounce_page_list, bpage, links);
792 total_bpages++;
793 free_bpages++;
794 splx(s);
795 count++;
796 numpages--;
797 }
798 return (count);
799 }
800
801 static int
802 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map)
803 {
804 int pages;
805
806 pages = MIN(free_bpages, map->pagesneeded - map->pagesreserved);
807 free_bpages -= pages;
808 reserved_bpages += pages;
809 map->pagesreserved += pages;
810 pages = map->pagesneeded - map->pagesreserved;
811
812 return (pages);
813 }
814
815 static bus_addr_t
816 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
817 bus_size_t size)
818 {
819 int s;
820 struct bounce_page *bpage;
821
822 if (map->pagesneeded == 0)
823 panic("add_bounce_page: map doesn't need any pages");
824 map->pagesneeded--;
825
826 if (map->pagesreserved == 0)
827 panic("add_bounce_page: map doesn't need any pages");
828 map->pagesreserved--;
829
830 s = splhigh();
831 bpage = STAILQ_FIRST(&bounce_page_list);
832 if (bpage == NULL)
833 panic("add_bounce_page: free page list is empty");
834
835 STAILQ_REMOVE_HEAD(&bounce_page_list, links);
836 reserved_bpages--;
837 active_bpages++;
838 splx(s);
839
840 bpage->datavaddr = vaddr;
841 bpage->datacount = size;
842 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
843 return (bpage->busaddr);
844 }
845
846 static void
847 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
848 {
849 int s;
850 struct bus_dmamap *map;
851
852 bpage->datavaddr = 0;
853 bpage->datacount = 0;
854
855 s = splhigh();
856 STAILQ_INSERT_HEAD(&bounce_page_list, bpage, links);
857 free_bpages++;
858 active_bpages--;
859 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
860 if (reserve_bounce_pages(map->dmat, map) == 0) {
861 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
862 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
863 map, links);
864 busdma_swi_pending = 1;
865 setsoftvm();
866 }
867 }
868 splx(s);
869 }
870
871 void
872 busdma_swi()
873 {
874 int s;
875 struct bus_dmamap *map;
876
877 s = splhigh();
878 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
879 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
880 splx(s);
881 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
882 map->callback, map->callback_arg, /*flags*/0);
883 s = splhigh();
884 }
885 splx(s);
886 }
Cache object: d8889088883e362c1ecb2e6afe7c6a5d
|