2 * Copyright (c) 1997, 1998 Justin T. Gibbs.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
28 * From amd64/busdma_machdep.c, r204214
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/malloc.h>
38 #include <sys/interrupt.h>
39 #include <sys/kernel.h>
43 #include <sys/memdesc.h>
44 #include <sys/mutex.h>
45 #include <sys/sysctl.h>
49 #include <vm/vm_extern.h>
50 #include <vm/vm_kern.h>
51 #include <vm/vm_page.h>
52 #include <vm/vm_map.h>
54 #include <machine/atomic.h>
55 #include <machine/bus.h>
56 #include <machine/cpufunc.h>
57 #include <machine/md_var.h>
61 #define MAX_BPAGES MIN(8192, physmem/40)
71 bus_dma_filter_t *filter;
79 bus_dma_lock_t *lockfunc;
81 struct bounce_zone *bounce_zone;
87 vm_offset_t vaddr; /* kva of bounce buffer */
88 bus_addr_t busaddr; /* Physical address */
89 vm_offset_t datavaddr; /* kva of client data */
90 bus_addr_t dataaddr; /* client physical address */
91 bus_size_t datacount; /* client data count */
92 STAILQ_ENTRY(bounce_page) links;
95 int busdma_swi_pending;
98 STAILQ_ENTRY(bounce_zone) links;
99 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
107 bus_size_t alignment;
111 struct sysctl_ctx_list sysctl_tree;
112 struct sysctl_oid *sysctl_tree_top;
115 static struct mtx bounce_lock;
116 static int total_bpages;
117 static int busdma_zonecount;
118 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
120 static SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
121 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
122 "Total bounce pages");
125 struct bp_list bpages;
130 bus_dma_segment_t *segments;
132 bus_dmamap_callback_t *callback;
134 STAILQ_ENTRY(bus_dmamap) links;
138 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
139 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
141 static void init_bounce_pages(void *dummy);
142 static int alloc_bounce_zone(bus_dma_tag_t dmat);
143 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
144 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
146 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
147 vm_offset_t vaddr, bus_addr_t addr,
149 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
150 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
153 * Return true if a match is made.
155 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'.
157 * If paddr is within the bounds of the dma tag then call the filter callback
158 * to check for a match, if there is no filter callback then assume a match.
161 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
168 if (dmat->filter == NULL && dmat->iommu == NULL &&
169 paddr > dmat->lowaddr && paddr <= dmat->highaddr)
171 if (dmat->filter == NULL &&
172 (paddr & (dmat->alignment - 1)) != 0)
174 if (dmat->filter != NULL &&
175 (*dmat->filter)(dmat->filterarg, paddr) != 0)
179 } while (retval == 0 && dmat != NULL);
184 * Convenience function for manipulating driver locks from busdma (during
185 * busdma_swi, for example). Drivers that don't provide their own locks
186 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own
187 * non-mutex locking scheme don't have to use this at all.
190 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
194 dmtx = (struct mtx *)arg;
203 panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
208 * dflt_lock should never get called. It gets put into the dma tag when
209 * lockfunc == NULL, which is only valid if the maps that are associated
210 * with the tag are meant to never be defered.
211 * XXX Should have a way to identify which driver is responsible here.
214 dflt_lock(void *arg, bus_dma_lock_op_t op)
216 panic("driver error: busdma dflt_lock called");
219 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
220 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
222 * Allocate a device specific dma_tag.
225 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
226 bus_addr_t boundary, bus_addr_t lowaddr,
227 bus_addr_t highaddr, bus_dma_filter_t *filter,
228 void *filterarg, bus_size_t maxsize, int nsegments,
229 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
230 void *lockfuncarg, bus_dma_tag_t *dmat)
232 bus_dma_tag_t newtag;
235 /* Basic sanity checking */
236 if (boundary != 0 && boundary < maxsegsz)
243 /* Return a NULL tag on failure */
246 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF,
248 if (newtag == NULL) {
249 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
250 __func__, newtag, 0, error);
254 newtag->parent = parent;
255 newtag->alignment = alignment;
256 newtag->boundary = boundary;
257 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
258 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
259 newtag->filter = filter;
260 newtag->filterarg = filterarg;
261 newtag->maxsize = maxsize;
262 newtag->nsegments = nsegments;
263 newtag->maxsegsz = maxsegsz;
264 newtag->flags = flags;
265 newtag->ref_count = 1; /* Count ourself */
266 newtag->map_count = 0;
267 if (lockfunc != NULL) {
268 newtag->lockfunc = lockfunc;
269 newtag->lockfuncarg = lockfuncarg;
271 newtag->lockfunc = dflt_lock;
272 newtag->lockfuncarg = NULL;
275 /* Take into account any restrictions imposed by our parent tag */
276 if (parent != NULL) {
277 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
278 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
279 if (newtag->boundary == 0)
280 newtag->boundary = parent->boundary;
281 else if (parent->boundary != 0)
282 newtag->boundary = MIN(parent->boundary,
284 if (newtag->filter == NULL) {
286 * Short circuit looking at our parent directly
287 * since we have encapsulated all of its information
289 newtag->filter = parent->filter;
290 newtag->filterarg = parent->filterarg;
291 newtag->parent = parent->parent;
293 if (newtag->parent != NULL)
294 atomic_add_int(&parent->ref_count, 1);
295 newtag->iommu = parent->iommu;
296 newtag->iommu_cookie = parent->iommu_cookie;
299 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) && newtag->iommu == NULL)
300 newtag->flags |= BUS_DMA_COULD_BOUNCE;
302 if (newtag->alignment > 1)
303 newtag->flags |= BUS_DMA_COULD_BOUNCE;
305 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
306 (flags & BUS_DMA_ALLOCNOW) != 0) {
307 struct bounce_zone *bz;
311 if ((error = alloc_bounce_zone(newtag)) != 0) {
312 free(newtag, M_DEVBUF);
315 bz = newtag->bounce_zone;
317 if (ptoa(bz->total_bpages) < maxsize) {
320 pages = atop(maxsize) - bz->total_bpages;
322 /* Add pages to our bounce pool */
323 if (alloc_bounce_pages(newtag, pages) < pages)
326 /* Performed initial allocation */
327 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
331 free(newtag, M_DEVBUF);
335 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
336 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
341 bus_dma_tag_destroy(bus_dma_tag_t dmat)
343 bus_dma_tag_t dmat_copy;
351 if (dmat->map_count != 0) {
356 while (dmat != NULL) {
357 bus_dma_tag_t parent;
359 parent = dmat->parent;
360 atomic_subtract_int(&dmat->ref_count, 1);
361 if (dmat->ref_count == 0) {
362 free(dmat, M_DEVBUF);
364 * Last reference count, so
365 * release our reference
366 * count on our parent.
374 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
379 * Allocate a handle for mapping from kva/uva/physical
380 * address space into bus device space.
383 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
389 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
392 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
393 __func__, dmat, ENOMEM);
399 * Bouncing might be required if the driver asks for an active
400 * exclusion region, a data alignment that is stricter than 1, and/or
401 * an active address boundary.
403 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
406 struct bounce_zone *bz;
409 if (dmat->bounce_zone == NULL) {
410 if ((error = alloc_bounce_zone(dmat)) != 0)
413 bz = dmat->bounce_zone;
415 /* Initialize the new map */
416 STAILQ_INIT(&((*mapp)->bpages));
419 * Attempt to add pages to our pool on a per-instance
420 * basis up to a sane limit.
422 if (dmat->alignment > 1)
423 maxpages = MAX_BPAGES;
425 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
426 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
427 || (bz->map_count > 0 && bz->total_bpages < maxpages)) {
430 pages = MAX(atop(dmat->maxsize), 1);
431 pages = MIN(maxpages - bz->total_bpages, pages);
432 pages = MAX(pages, 1);
433 if (alloc_bounce_pages(dmat, pages) < pages)
436 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
438 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
447 (*mapp)->segments = (bus_dma_segment_t *)malloc(
448 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
450 if ((*mapp)->segments == NULL) {
451 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
452 __func__, dmat, ENOMEM);
458 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
459 __func__, dmat, dmat->flags, error);
464 * Destroy a handle for mapping from kva/uva/physical
465 * address space into bus device space.
468 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
470 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
471 if (STAILQ_FIRST(&map->bpages) != NULL) {
472 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
473 __func__, dmat, EBUSY);
476 if (dmat->bounce_zone)
477 dmat->bounce_zone->map_count--;
479 free(map->segments, M_DEVBUF);
482 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
488 * Allocate a piece of memory that can be efficiently mapped into
489 * bus device space based on the constraints lited in the dma tag.
490 * A dmamap to for use with dmamap_load is also allocated.
493 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
499 if (flags & BUS_DMA_NOWAIT)
504 bus_dmamap_create(dmat, flags, mapp);
506 if (flags & BUS_DMA_ZERO)
509 if (flags & BUS_DMA_NOCACHE)
510 attr = VM_MEMATTR_UNCACHEABLE;
513 attr = VM_MEMATTR_DEFAULT;
517 * (dmat->alignment <= dmat->maxsize) is just a quick hack; the exact
518 * alignment guarantees of malloc need to be nailed down, and the
519 * code below should be rewritten to take that into account.
521 * In the meantime, we'll warn the user if malloc gets it wrong.
523 if ((dmat->maxsize <= PAGE_SIZE) &&
524 (dmat->alignment <= dmat->maxsize) &&
525 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem) &&
526 attr == VM_MEMATTR_DEFAULT) {
527 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
530 * XXX Use Contigmalloc until it is merged into this facility
531 * and handles multi-seg allocations. Nobody is doing
532 * multi-seg allocations yet though.
533 * XXX Certain AGP hardware does.
535 *vaddr = (void *)kmem_alloc_contig(kmem_arena, dmat->maxsize,
536 mflags, 0ul, dmat->lowaddr, dmat->alignment ?
537 dmat->alignment : 1ul, dmat->boundary, attr);
538 (*mapp)->contigalloc = 1;
540 if (*vaddr == NULL) {
541 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
542 __func__, dmat, dmat->flags, ENOMEM);
544 } else if (vtophys(*vaddr) & (dmat->alignment - 1)) {
545 printf("bus_dmamem_alloc failed to align memory properly.\n");
547 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
548 __func__, dmat, dmat->flags, 0);
553 * Free a piece of memory and it's allociated dmamap, that was allocated
554 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
557 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
560 if (!map->contigalloc)
561 free(vaddr, M_DEVBUF);
563 kmem_free(kmem_arena, (vm_offset_t)vaddr, dmat->maxsize);
564 bus_dmamap_destroy(dmat, map);
565 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
569 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf,
570 bus_size_t buflen, int flags)
575 if (map->pagesneeded == 0) {
576 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
577 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
578 dmat->boundary, dmat->alignment);
579 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map, map->pagesneeded);
581 * Count the number of bounce pages
582 * needed in order to complete this transfer
585 while (buflen != 0) {
586 sgsize = MIN(buflen, dmat->maxsegsz);
587 if (run_filter(dmat, curaddr) != 0) {
588 sgsize = MIN(sgsize, PAGE_SIZE);
594 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
599 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap,
600 void *buf, bus_size_t buflen, int flags)
603 vm_offset_t vendaddr;
606 if (map->pagesneeded == 0) {
607 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
608 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
609 dmat->boundary, dmat->alignment);
610 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map, map->pagesneeded);
612 * Count the number of bounce pages
613 * needed in order to complete this transfer
615 vaddr = (vm_offset_t)buf;
616 vendaddr = (vm_offset_t)buf + buflen;
618 while (vaddr < vendaddr) {
621 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK);
622 if (pmap == kernel_pmap)
623 paddr = pmap_kextract(vaddr);
625 paddr = pmap_extract(pmap, vaddr);
626 if (run_filter(dmat, paddr) != 0) {
627 sg_len = roundup2(sg_len, dmat->alignment);
632 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
637 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags)
640 /* Reserve Necessary Bounce Pages */
641 mtx_lock(&bounce_lock);
642 if (flags & BUS_DMA_NOWAIT) {
643 if (reserve_bounce_pages(dmat, map, 0) != 0) {
644 mtx_unlock(&bounce_lock);
648 if (reserve_bounce_pages(dmat, map, 1) != 0) {
649 /* Queue us for resources */
650 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
652 mtx_unlock(&bounce_lock);
653 return (EINPROGRESS);
656 mtx_unlock(&bounce_lock);
662 * Add a single contiguous physical range to the segment list.
665 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, bus_addr_t curaddr,
666 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp)
668 bus_addr_t baddr, bmask;
672 * Make sure we don't cross any boundaries.
674 bmask = ~(dmat->boundary - 1);
675 if (dmat->boundary > 0) {
676 baddr = (curaddr + dmat->boundary) & bmask;
677 if (sgsize > (baddr - curaddr))
678 sgsize = (baddr - curaddr);
682 * Insert chunk into a segment, coalescing with
683 * previous segment if possible.
688 segs[seg].ds_addr = curaddr;
689 segs[seg].ds_len = sgsize;
691 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len &&
692 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
693 (dmat->boundary == 0 ||
694 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
695 segs[seg].ds_len += sgsize;
697 if (++seg >= dmat->nsegments)
699 segs[seg].ds_addr = curaddr;
700 segs[seg].ds_len = sgsize;
708 * Utility function to load a physical buffer. segp contains
709 * the starting segment on entrace, and the ending segment on exit.
712 _bus_dmamap_load_phys(bus_dma_tag_t dmat,
714 vm_paddr_t buf, bus_size_t buflen,
716 bus_dma_segment_t *segs,
724 segs = map->segments;
726 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
727 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags);
728 if (map->pagesneeded != 0) {
729 error = _bus_dmamap_reserve_pages(dmat, map, flags);
737 sgsize = MIN(buflen, dmat->maxsegsz);
738 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
739 sgsize = MIN(sgsize, PAGE_SIZE);
740 curaddr = add_bounce_page(dmat, map, 0, curaddr,
743 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
754 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
758 _bus_dmamap_load_ma(bus_dma_tag_t dmat, bus_dmamap_t map,
759 struct vm_page **ma, bus_size_t tlen, int ma_offs, int flags,
760 bus_dma_segment_t *segs, int *segp)
763 return (bus_dmamap_load_ma_triv(dmat, map, ma, tlen, ma_offs, flags,
768 * Utility function to load a linear buffer. segp contains
769 * the starting segment on entrance, and the ending segment on exit.
772 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
774 void *buf, bus_size_t buflen,
777 bus_dma_segment_t *segs,
786 segs = map->segments;
788 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
789 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags);
790 if (map->pagesneeded != 0) {
791 error = _bus_dmamap_reserve_pages(dmat, map, flags);
797 vaddr = (vm_offset_t)buf;
800 bus_size_t max_sgsize;
803 * Get the physical address for this segment.
805 if (pmap == kernel_pmap)
806 curaddr = pmap_kextract(vaddr);
808 curaddr = pmap_extract(pmap, vaddr);
811 * Compute the segment size, and adjust counts.
813 max_sgsize = MIN(buflen, dmat->maxsegsz);
814 sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK);
815 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
816 sgsize = roundup2(sgsize, dmat->alignment);
817 sgsize = MIN(sgsize, max_sgsize);
818 curaddr = add_bounce_page(dmat, map, vaddr, curaddr,
821 sgsize = MIN(sgsize, max_sgsize);
824 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
835 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
839 __bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map,
840 struct memdesc *mem, bus_dmamap_callback_t *callback,
844 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
847 map->callback = callback;
848 map->callback_arg = callback_arg;
853 _bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map,
854 bus_dma_segment_t *segs, int nsegs, int error)
859 memcpy(map->segments, segs, map->nsegs*sizeof(segs[0]));
860 if (dmat->iommu != NULL)
861 IOMMU_MAP(dmat->iommu, map->segments, &map->nsegs,
862 dmat->lowaddr, dmat->highaddr, dmat->alignment,
863 dmat->boundary, dmat->iommu_cookie);
866 memcpy(segs, map->segments, map->nsegs*sizeof(segs[0]));
868 segs = map->segments;
874 * Release the mapping held by map.
877 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
879 struct bounce_page *bpage;
882 IOMMU_UNMAP(dmat->iommu, map->segments, map->nsegs, dmat->iommu_cookie);
886 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
887 STAILQ_REMOVE_HEAD(&map->bpages, links);
888 free_bounce_page(dmat, bpage);
893 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
895 struct bounce_page *bpage;
897 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
899 * Handle data bouncing. We might also
900 * want to add support for invalidating
901 * the caches on broken hardware
903 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
904 "performing bounce", __func__, dmat, dmat->flags, op);
906 if (op & BUS_DMASYNC_PREWRITE) {
907 while (bpage != NULL) {
908 if (bpage->datavaddr != 0)
909 bcopy((void *)bpage->datavaddr,
910 (void *)bpage->vaddr,
913 physcopyout(bpage->dataaddr,
914 (void *)bpage->vaddr,
916 bpage = STAILQ_NEXT(bpage, links);
918 dmat->bounce_zone->total_bounced++;
921 if (op & BUS_DMASYNC_POSTREAD) {
922 while (bpage != NULL) {
923 if (bpage->datavaddr != 0)
924 bcopy((void *)bpage->vaddr,
925 (void *)bpage->datavaddr,
928 physcopyin((void *)bpage->vaddr,
929 bpage->dataaddr, bpage->datacount);
930 bpage = STAILQ_NEXT(bpage, links);
932 dmat->bounce_zone->total_bounced++;
940 init_bounce_pages(void *dummy __unused)
944 STAILQ_INIT(&bounce_zone_list);
945 STAILQ_INIT(&bounce_map_waitinglist);
946 STAILQ_INIT(&bounce_map_callbacklist);
947 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
949 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
951 static struct sysctl_ctx_list *
952 busdma_sysctl_tree(struct bounce_zone *bz)
954 return (&bz->sysctl_tree);
957 static struct sysctl_oid *
958 busdma_sysctl_tree_top(struct bounce_zone *bz)
960 return (bz->sysctl_tree_top);
964 alloc_bounce_zone(bus_dma_tag_t dmat)
966 struct bounce_zone *bz;
968 /* Check to see if we already have a suitable zone */
969 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
970 if ((dmat->alignment <= bz->alignment)
971 && (dmat->lowaddr >= bz->lowaddr)) {
972 dmat->bounce_zone = bz;
977 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
978 M_NOWAIT | M_ZERO)) == NULL)
981 STAILQ_INIT(&bz->bounce_page_list);
983 bz->reserved_bpages = 0;
984 bz->active_bpages = 0;
985 bz->lowaddr = dmat->lowaddr;
986 bz->alignment = MAX(dmat->alignment, PAGE_SIZE);
988 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
990 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
991 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
992 dmat->bounce_zone = bz;
994 sysctl_ctx_init(&bz->sysctl_tree);
995 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
996 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
998 if (bz->sysctl_tree_top == NULL) {
999 sysctl_ctx_free(&bz->sysctl_tree);
1000 return (0); /* XXX error code? */
1003 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1004 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1005 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1006 "Total bounce pages");
1007 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1008 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1009 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1010 "Free bounce pages");
1011 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1012 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1013 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1014 "Reserved bounce pages");
1015 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1016 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1017 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1018 "Active bounce pages");
1019 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1020 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1021 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1022 "Total bounce requests");
1023 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1024 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1025 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1026 "Total bounce requests that were deferred");
1027 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1028 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1029 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1030 SYSCTL_ADD_UAUTO(busdma_sysctl_tree(bz),
1031 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1032 "alignment", CTLFLAG_RD, &bz->alignment, "");
1038 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1040 struct bounce_zone *bz;
1043 bz = dmat->bounce_zone;
1045 while (numpages > 0) {
1046 struct bounce_page *bpage;
1048 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1053 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1058 if (bpage->vaddr == 0) {
1059 free(bpage, M_DEVBUF);
1062 bpage->busaddr = pmap_kextract(bpage->vaddr);
1063 mtx_lock(&bounce_lock);
1064 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1068 mtx_unlock(&bounce_lock);
1076 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1078 struct bounce_zone *bz;
1081 mtx_assert(&bounce_lock, MA_OWNED);
1082 bz = dmat->bounce_zone;
1083 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1084 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1085 return (map->pagesneeded - (map->pagesreserved + pages));
1086 bz->free_bpages -= pages;
1087 bz->reserved_bpages += pages;
1088 map->pagesreserved += pages;
1089 pages = map->pagesneeded - map->pagesreserved;
1095 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1096 bus_addr_t addr, bus_size_t size)
1098 struct bounce_zone *bz;
1099 struct bounce_page *bpage;
1101 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1103 bz = dmat->bounce_zone;
1104 if (map->pagesneeded == 0)
1105 panic("add_bounce_page: map doesn't need any pages");
1108 if (map->pagesreserved == 0)
1109 panic("add_bounce_page: map doesn't need any pages");
1110 map->pagesreserved--;
1112 mtx_lock(&bounce_lock);
1113 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1115 panic("add_bounce_page: free page list is empty");
1117 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1118 bz->reserved_bpages--;
1119 bz->active_bpages++;
1120 mtx_unlock(&bounce_lock);
1122 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1123 /* Page offset needs to be preserved. */
1124 bpage->vaddr |= addr & PAGE_MASK;
1125 bpage->busaddr |= addr & PAGE_MASK;
1127 bpage->datavaddr = vaddr;
1128 bpage->dataaddr = addr;
1129 bpage->datacount = size;
1130 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1131 return (bpage->busaddr);
1135 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1137 struct bus_dmamap *map;
1138 struct bounce_zone *bz;
1140 bz = dmat->bounce_zone;
1141 bpage->datavaddr = 0;
1142 bpage->datacount = 0;
1143 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1145 * Reset the bounce page to start at offset 0. Other uses
1146 * of this bounce page may need to store a full page of
1147 * data and/or assume it starts on a page boundary.
1149 bpage->vaddr &= ~PAGE_MASK;
1150 bpage->busaddr &= ~PAGE_MASK;
1153 mtx_lock(&bounce_lock);
1154 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1156 bz->active_bpages--;
1157 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1158 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1159 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1160 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1162 busdma_swi_pending = 1;
1163 bz->total_deferred++;
1164 swi_sched(vm_ih, 0);
1167 mtx_unlock(&bounce_lock);
1174 struct bus_dmamap *map;
1176 mtx_lock(&bounce_lock);
1177 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1178 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1179 mtx_unlock(&bounce_lock);
1181 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1182 bus_dmamap_load_mem(map->dmat, map, &map->mem,
1183 map->callback, map->callback_arg,
1185 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1186 mtx_lock(&bounce_lock);
1188 mtx_unlock(&bounce_lock);
1192 bus_dma_tag_set_iommu(bus_dma_tag_t tag, struct device *iommu, void *cookie)
1195 tag->iommu_cookie = cookie;