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 vm_page_t datapage; /* physical page of client data */
91 vm_offset_t dataoffs; /* page offset of client data */
92 bus_size_t datacount; /* client data count */
93 STAILQ_ENTRY(bounce_page) links;
96 int busdma_swi_pending;
99 STAILQ_ENTRY(bounce_zone) links;
100 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
108 bus_size_t alignment;
112 struct sysctl_ctx_list sysctl_tree;
113 struct sysctl_oid *sysctl_tree_top;
116 static struct mtx bounce_lock;
117 static int total_bpages;
118 static int busdma_zonecount;
119 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
121 static SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
122 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
123 "Total bounce pages");
126 struct bp_list bpages;
131 bus_dma_segment_t *segments;
133 bus_dmamap_callback_t *callback;
135 STAILQ_ENTRY(bus_dmamap) links;
139 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
140 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
142 static void init_bounce_pages(void *dummy);
143 static int alloc_bounce_zone(bus_dma_tag_t dmat);
144 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
145 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
147 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
148 vm_offset_t vaddr, bus_addr_t addr,
150 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
151 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
154 * Return true if a match is made.
156 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'.
158 * If paddr is within the bounds of the dma tag then call the filter callback
159 * to check for a match, if there is no filter callback then assume a match.
162 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
169 if (dmat->filter == NULL && dmat->iommu == NULL &&
170 paddr > dmat->lowaddr && paddr <= dmat->highaddr)
172 if (dmat->filter == NULL &&
173 (paddr & (dmat->alignment - 1)) != 0)
175 if (dmat->filter != NULL &&
176 (*dmat->filter)(dmat->filterarg, paddr) != 0)
180 } while (retval == 0 && dmat != NULL);
185 * Convenience function for manipulating driver locks from busdma (during
186 * busdma_swi, for example). Drivers that don't provide their own locks
187 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own
188 * non-mutex locking scheme don't have to use this at all.
191 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
195 dmtx = (struct mtx *)arg;
204 panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
209 * dflt_lock should never get called. It gets put into the dma tag when
210 * lockfunc == NULL, which is only valid if the maps that are associated
211 * with the tag are meant to never be defered.
212 * XXX Should have a way to identify which driver is responsible here.
215 dflt_lock(void *arg, bus_dma_lock_op_t op)
217 panic("driver error: busdma dflt_lock called");
220 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
221 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
223 * Allocate a device specific dma_tag.
226 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
227 bus_addr_t boundary, bus_addr_t lowaddr,
228 bus_addr_t highaddr, bus_dma_filter_t *filter,
229 void *filterarg, bus_size_t maxsize, int nsegments,
230 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
231 void *lockfuncarg, bus_dma_tag_t *dmat)
233 bus_dma_tag_t newtag;
236 /* Basic sanity checking */
237 if (boundary != 0 && boundary < maxsegsz)
244 /* Return a NULL tag on failure */
247 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF,
249 if (newtag == NULL) {
250 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
251 __func__, newtag, 0, error);
255 newtag->parent = parent;
256 newtag->alignment = alignment;
257 newtag->boundary = boundary;
258 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
259 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
260 newtag->filter = filter;
261 newtag->filterarg = filterarg;
262 newtag->maxsize = maxsize;
263 newtag->nsegments = nsegments;
264 newtag->maxsegsz = maxsegsz;
265 newtag->flags = flags;
266 newtag->ref_count = 1; /* Count ourself */
267 newtag->map_count = 0;
268 if (lockfunc != NULL) {
269 newtag->lockfunc = lockfunc;
270 newtag->lockfuncarg = lockfuncarg;
272 newtag->lockfunc = dflt_lock;
273 newtag->lockfuncarg = NULL;
276 /* Take into account any restrictions imposed by our parent tag */
277 if (parent != NULL) {
278 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
279 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
280 if (newtag->boundary == 0)
281 newtag->boundary = parent->boundary;
282 else if (parent->boundary != 0)
283 newtag->boundary = MIN(parent->boundary,
285 if (newtag->filter == NULL) {
287 * Short circuit looking at our parent directly
288 * since we have encapsulated all of its information
290 newtag->filter = parent->filter;
291 newtag->filterarg = parent->filterarg;
292 newtag->parent = parent->parent;
294 if (newtag->parent != NULL)
295 atomic_add_int(&parent->ref_count, 1);
296 newtag->iommu = parent->iommu;
297 newtag->iommu_cookie = parent->iommu_cookie;
300 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) && newtag->iommu == NULL)
301 newtag->flags |= BUS_DMA_COULD_BOUNCE;
303 if (newtag->alignment > 1)
304 newtag->flags |= BUS_DMA_COULD_BOUNCE;
306 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
307 (flags & BUS_DMA_ALLOCNOW) != 0) {
308 struct bounce_zone *bz;
312 if ((error = alloc_bounce_zone(newtag)) != 0) {
313 free(newtag, M_DEVBUF);
316 bz = newtag->bounce_zone;
318 if (ptoa(bz->total_bpages) < maxsize) {
321 pages = atop(maxsize) - bz->total_bpages;
323 /* Add pages to our bounce pool */
324 if (alloc_bounce_pages(newtag, pages) < pages)
327 /* Performed initial allocation */
328 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
332 free(newtag, M_DEVBUF);
336 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
337 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
342 bus_dma_tag_destroy(bus_dma_tag_t dmat)
344 bus_dma_tag_t dmat_copy;
352 if (dmat->map_count != 0) {
357 while (dmat != NULL) {
358 bus_dma_tag_t parent;
360 parent = dmat->parent;
361 atomic_subtract_int(&dmat->ref_count, 1);
362 if (dmat->ref_count == 0) {
363 free(dmat, M_DEVBUF);
365 * Last reference count, so
366 * release our reference
367 * count on our parent.
375 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
380 * Allocate a handle for mapping from kva/uva/physical
381 * address space into bus device space.
384 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
390 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
393 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
394 __func__, dmat, ENOMEM);
400 * Bouncing might be required if the driver asks for an active
401 * exclusion region, a data alignment that is stricter than 1, and/or
402 * an active address boundary.
404 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
407 struct bounce_zone *bz;
410 if (dmat->bounce_zone == NULL) {
411 if ((error = alloc_bounce_zone(dmat)) != 0)
414 bz = dmat->bounce_zone;
416 /* Initialize the new map */
417 STAILQ_INIT(&((*mapp)->bpages));
420 * Attempt to add pages to our pool on a per-instance
421 * basis up to a sane limit.
423 if (dmat->alignment > 1)
424 maxpages = MAX_BPAGES;
426 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
427 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
428 || (bz->map_count > 0 && bz->total_bpages < maxpages)) {
431 pages = MAX(atop(dmat->maxsize), 1);
432 pages = MIN(maxpages - bz->total_bpages, pages);
433 pages = MAX(pages, 1);
434 if (alloc_bounce_pages(dmat, pages) < pages)
437 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
439 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
448 (*mapp)->segments = (bus_dma_segment_t *)malloc(
449 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
451 if ((*mapp)->segments == NULL) {
452 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
453 __func__, dmat, ENOMEM);
459 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
460 __func__, dmat, dmat->flags, error);
465 * Destroy a handle for mapping from kva/uva/physical
466 * address space into bus device space.
469 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
471 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
472 if (STAILQ_FIRST(&map->bpages) != NULL) {
473 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
474 __func__, dmat, EBUSY);
477 if (dmat->bounce_zone)
478 dmat->bounce_zone->map_count--;
480 free(map->segments, M_DEVBUF);
483 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
489 * Allocate a piece of memory that can be efficiently mapped into
490 * bus device space based on the constraints lited in the dma tag.
491 * A dmamap to for use with dmamap_load is also allocated.
494 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
500 if (flags & BUS_DMA_NOWAIT)
505 bus_dmamap_create(dmat, flags, mapp);
507 if (flags & BUS_DMA_ZERO)
510 if (flags & BUS_DMA_NOCACHE)
511 attr = VM_MEMATTR_UNCACHEABLE;
514 attr = VM_MEMATTR_DEFAULT;
518 * (dmat->alignment <= dmat->maxsize) is just a quick hack; the exact
519 * alignment guarantees of malloc need to be nailed down, and the
520 * code below should be rewritten to take that into account.
522 * In the meantime, we'll warn the user if malloc gets it wrong.
524 if ((dmat->maxsize <= PAGE_SIZE) &&
525 (dmat->alignment <= dmat->maxsize) &&
526 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem) &&
527 attr == VM_MEMATTR_DEFAULT) {
528 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
531 * XXX Use Contigmalloc until it is merged into this facility
532 * and handles multi-seg allocations. Nobody is doing
533 * multi-seg allocations yet though.
534 * XXX Certain AGP hardware does.
536 *vaddr = (void *)kmem_alloc_contig(kmem_arena, dmat->maxsize,
537 mflags, 0ul, dmat->lowaddr, dmat->alignment ?
538 dmat->alignment : 1ul, dmat->boundary, attr);
539 (*mapp)->contigalloc = 1;
541 if (*vaddr == NULL) {
542 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
543 __func__, dmat, dmat->flags, ENOMEM);
545 } else if (vtophys(*vaddr) & (dmat->alignment - 1)) {
546 printf("bus_dmamem_alloc failed to align memory properly.\n");
548 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
549 __func__, dmat, dmat->flags, 0);
554 * Free a piece of memory and it's allociated dmamap, that was allocated
555 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
558 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
561 if (!map->contigalloc)
562 free(vaddr, M_DEVBUF);
564 kmem_free(kmem_arena, (vm_offset_t)vaddr, dmat->maxsize);
565 bus_dmamap_destroy(dmat, map);
566 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
570 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf,
571 bus_size_t buflen, int flags)
576 if (map->pagesneeded == 0) {
577 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
578 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
579 dmat->boundary, dmat->alignment);
580 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map, map->pagesneeded);
582 * Count the number of bounce pages
583 * needed in order to complete this transfer
586 while (buflen != 0) {
587 sgsize = MIN(buflen, dmat->maxsegsz);
588 if (run_filter(dmat, curaddr) != 0) {
590 PAGE_SIZE - (curaddr & PAGE_MASK));
596 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
601 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap,
602 void *buf, bus_size_t buflen, int flags)
605 vm_offset_t vendaddr;
608 if (map->pagesneeded == 0) {
609 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
610 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
611 dmat->boundary, dmat->alignment);
612 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map, map->pagesneeded);
614 * Count the number of bounce pages
615 * needed in order to complete this transfer
617 vaddr = (vm_offset_t)buf;
618 vendaddr = (vm_offset_t)buf + buflen;
620 while (vaddr < vendaddr) {
623 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK);
624 if (pmap == kernel_pmap)
625 paddr = pmap_kextract(vaddr);
627 paddr = pmap_extract(pmap, vaddr);
628 if (run_filter(dmat, paddr) != 0) {
629 sg_len = roundup2(sg_len, dmat->alignment);
634 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
639 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags)
642 /* Reserve Necessary Bounce Pages */
643 mtx_lock(&bounce_lock);
644 if (flags & BUS_DMA_NOWAIT) {
645 if (reserve_bounce_pages(dmat, map, 0) != 0) {
646 mtx_unlock(&bounce_lock);
650 if (reserve_bounce_pages(dmat, map, 1) != 0) {
651 /* Queue us for resources */
652 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
654 mtx_unlock(&bounce_lock);
655 return (EINPROGRESS);
658 mtx_unlock(&bounce_lock);
664 * Add a single contiguous physical range to the segment list.
667 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, bus_addr_t curaddr,
668 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp)
670 bus_addr_t baddr, bmask;
674 * Make sure we don't cross any boundaries.
676 bmask = ~(dmat->boundary - 1);
677 if (dmat->boundary > 0) {
678 baddr = (curaddr + dmat->boundary) & bmask;
679 if (sgsize > (baddr - curaddr))
680 sgsize = (baddr - curaddr);
684 * Insert chunk into a segment, coalescing with
685 * previous segment if possible.
690 segs[seg].ds_addr = curaddr;
691 segs[seg].ds_len = sgsize;
693 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len &&
694 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
695 (dmat->boundary == 0 ||
696 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
697 segs[seg].ds_len += sgsize;
699 if (++seg >= dmat->nsegments)
701 segs[seg].ds_addr = curaddr;
702 segs[seg].ds_len = sgsize;
710 * Utility function to load a physical buffer. segp contains
711 * the starting segment on entrace, and the ending segment on exit.
714 _bus_dmamap_load_phys(bus_dma_tag_t dmat,
716 vm_paddr_t buf, bus_size_t buflen,
718 bus_dma_segment_t *segs,
726 segs = map->segments;
728 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
729 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags);
730 if (map->pagesneeded != 0) {
731 error = _bus_dmamap_reserve_pages(dmat, map, flags);
739 sgsize = MIN(buflen, dmat->maxsegsz);
740 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
741 sgsize = MIN(sgsize, PAGE_SIZE - (curaddr & PAGE_MASK));
742 curaddr = add_bounce_page(dmat, map, 0, curaddr,
745 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
756 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
760 _bus_dmamap_load_ma(bus_dma_tag_t dmat, bus_dmamap_t map,
761 struct vm_page **ma, bus_size_t tlen, int ma_offs, int flags,
762 bus_dma_segment_t *segs, int *segp)
765 return (bus_dmamap_load_ma_triv(dmat, map, ma, tlen, ma_offs, flags,
770 * Utility function to load a linear buffer. segp contains
771 * the starting segment on entrance, and the ending segment on exit.
774 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
776 void *buf, bus_size_t buflen,
779 bus_dma_segment_t *segs,
784 vm_offset_t kvaddr, vaddr;
788 segs = map->segments;
790 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
791 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags);
792 if (map->pagesneeded != 0) {
793 error = _bus_dmamap_reserve_pages(dmat, map, flags);
799 vaddr = (vm_offset_t)buf;
802 bus_size_t max_sgsize;
805 * Get the physical address for this segment.
807 if (pmap == kernel_pmap) {
808 curaddr = pmap_kextract(vaddr);
811 curaddr = pmap_extract(pmap, vaddr);
816 * Compute the segment size, and adjust counts.
818 max_sgsize = MIN(buflen, dmat->maxsegsz);
819 sgsize = PAGE_SIZE - (curaddr & PAGE_MASK);
820 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
821 sgsize = roundup2(sgsize, dmat->alignment);
822 sgsize = MIN(sgsize, max_sgsize);
823 curaddr = add_bounce_page(dmat, map, kvaddr, curaddr,
826 sgsize = MIN(sgsize, max_sgsize);
829 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
840 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
844 __bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map,
845 struct memdesc *mem, bus_dmamap_callback_t *callback,
849 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
852 map->callback = callback;
853 map->callback_arg = callback_arg;
858 _bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map,
859 bus_dma_segment_t *segs, int nsegs, int error)
864 memcpy(map->segments, segs, map->nsegs*sizeof(segs[0]));
865 if (dmat->iommu != NULL)
866 IOMMU_MAP(dmat->iommu, map->segments, &map->nsegs,
867 dmat->lowaddr, dmat->highaddr, dmat->alignment,
868 dmat->boundary, dmat->iommu_cookie);
871 memcpy(segs, map->segments, map->nsegs*sizeof(segs[0]));
873 segs = map->segments;
879 * Release the mapping held by map.
882 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
884 struct bounce_page *bpage;
887 IOMMU_UNMAP(dmat->iommu, map->segments, map->nsegs, dmat->iommu_cookie);
891 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
892 STAILQ_REMOVE_HEAD(&map->bpages, links);
893 free_bounce_page(dmat, bpage);
898 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
900 struct bounce_page *bpage;
901 vm_offset_t datavaddr, tempvaddr;
903 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
906 * Handle data bouncing. We might also
907 * want to add support for invalidating
908 * the caches on broken hardware
910 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
911 "performing bounce", __func__, dmat, dmat->flags, op);
913 if (op & BUS_DMASYNC_PREWRITE) {
914 while (bpage != NULL) {
916 datavaddr = bpage->datavaddr;
917 if (datavaddr == 0) {
918 tempvaddr = pmap_quick_enter_page(
920 datavaddr = tempvaddr |
924 bcopy((void *)datavaddr,
925 (void *)bpage->vaddr, bpage->datacount);
928 pmap_quick_remove_page(tempvaddr);
929 bpage = STAILQ_NEXT(bpage, links);
931 dmat->bounce_zone->total_bounced++;
934 if (op & BUS_DMASYNC_POSTREAD) {
935 while (bpage != NULL) {
937 datavaddr = bpage->datavaddr;
938 if (datavaddr == 0) {
939 tempvaddr = pmap_quick_enter_page(
941 datavaddr = tempvaddr |
945 bcopy((void *)bpage->vaddr,
946 (void *)datavaddr, bpage->datacount);
949 pmap_quick_remove_page(tempvaddr);
950 bpage = STAILQ_NEXT(bpage, links);
952 dmat->bounce_zone->total_bounced++;
960 init_bounce_pages(void *dummy __unused)
964 STAILQ_INIT(&bounce_zone_list);
965 STAILQ_INIT(&bounce_map_waitinglist);
966 STAILQ_INIT(&bounce_map_callbacklist);
967 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
969 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
971 static struct sysctl_ctx_list *
972 busdma_sysctl_tree(struct bounce_zone *bz)
974 return (&bz->sysctl_tree);
977 static struct sysctl_oid *
978 busdma_sysctl_tree_top(struct bounce_zone *bz)
980 return (bz->sysctl_tree_top);
984 alloc_bounce_zone(bus_dma_tag_t dmat)
986 struct bounce_zone *bz;
988 /* Check to see if we already have a suitable zone */
989 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
990 if ((dmat->alignment <= bz->alignment)
991 && (dmat->lowaddr >= bz->lowaddr)) {
992 dmat->bounce_zone = bz;
997 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
998 M_NOWAIT | M_ZERO)) == NULL)
1001 STAILQ_INIT(&bz->bounce_page_list);
1002 bz->free_bpages = 0;
1003 bz->reserved_bpages = 0;
1004 bz->active_bpages = 0;
1005 bz->lowaddr = dmat->lowaddr;
1006 bz->alignment = MAX(dmat->alignment, PAGE_SIZE);
1008 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
1010 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
1011 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
1012 dmat->bounce_zone = bz;
1014 sysctl_ctx_init(&bz->sysctl_tree);
1015 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
1016 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1018 if (bz->sysctl_tree_top == NULL) {
1019 sysctl_ctx_free(&bz->sysctl_tree);
1020 return (0); /* XXX error code? */
1023 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1024 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1025 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1026 "Total bounce pages");
1027 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1028 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1029 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1030 "Free bounce pages");
1031 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1032 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1033 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1034 "Reserved bounce pages");
1035 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1036 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1037 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1038 "Active bounce pages");
1039 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1040 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1041 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1042 "Total bounce requests");
1043 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1044 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1045 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1046 "Total bounce requests that were deferred");
1047 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1048 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1049 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1050 SYSCTL_ADD_UAUTO(busdma_sysctl_tree(bz),
1051 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1052 "alignment", CTLFLAG_RD, &bz->alignment, "");
1058 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1060 struct bounce_zone *bz;
1063 bz = dmat->bounce_zone;
1065 while (numpages > 0) {
1066 struct bounce_page *bpage;
1068 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1073 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1078 if (bpage->vaddr == 0) {
1079 free(bpage, M_DEVBUF);
1082 bpage->busaddr = pmap_kextract(bpage->vaddr);
1083 mtx_lock(&bounce_lock);
1084 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1088 mtx_unlock(&bounce_lock);
1096 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1098 struct bounce_zone *bz;
1101 mtx_assert(&bounce_lock, MA_OWNED);
1102 bz = dmat->bounce_zone;
1103 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1104 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1105 return (map->pagesneeded - (map->pagesreserved + pages));
1106 bz->free_bpages -= pages;
1107 bz->reserved_bpages += pages;
1108 map->pagesreserved += pages;
1109 pages = map->pagesneeded - map->pagesreserved;
1115 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1116 bus_addr_t addr, bus_size_t size)
1118 struct bounce_zone *bz;
1119 struct bounce_page *bpage;
1121 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1123 bz = dmat->bounce_zone;
1124 if (map->pagesneeded == 0)
1125 panic("add_bounce_page: map doesn't need any pages");
1128 if (map->pagesreserved == 0)
1129 panic("add_bounce_page: map doesn't need any pages");
1130 map->pagesreserved--;
1132 mtx_lock(&bounce_lock);
1133 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1135 panic("add_bounce_page: free page list is empty");
1137 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1138 bz->reserved_bpages--;
1139 bz->active_bpages++;
1140 mtx_unlock(&bounce_lock);
1142 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1143 /* Page offset needs to be preserved. */
1144 bpage->vaddr |= addr & PAGE_MASK;
1145 bpage->busaddr |= addr & PAGE_MASK;
1147 bpage->datavaddr = vaddr;
1148 bpage->datapage = PHYS_TO_VM_PAGE(addr);
1149 bpage->dataoffs = addr & PAGE_MASK;
1150 bpage->datacount = size;
1151 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1152 return (bpage->busaddr);
1156 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1158 struct bus_dmamap *map;
1159 struct bounce_zone *bz;
1161 bz = dmat->bounce_zone;
1162 bpage->datavaddr = 0;
1163 bpage->datacount = 0;
1164 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1166 * Reset the bounce page to start at offset 0. Other uses
1167 * of this bounce page may need to store a full page of
1168 * data and/or assume it starts on a page boundary.
1170 bpage->vaddr &= ~PAGE_MASK;
1171 bpage->busaddr &= ~PAGE_MASK;
1174 mtx_lock(&bounce_lock);
1175 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1177 bz->active_bpages--;
1178 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1179 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1180 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1181 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1183 busdma_swi_pending = 1;
1184 bz->total_deferred++;
1185 swi_sched(vm_ih, 0);
1188 mtx_unlock(&bounce_lock);
1195 struct bus_dmamap *map;
1197 mtx_lock(&bounce_lock);
1198 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1199 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1200 mtx_unlock(&bounce_lock);
1202 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1203 bus_dmamap_load_mem(map->dmat, map, &map->mem,
1204 map->callback, map->callback_arg,
1206 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1207 mtx_lock(&bounce_lock);
1209 mtx_unlock(&bounce_lock);
1213 bus_dma_tag_set_iommu(bus_dma_tag_t tag, device_t iommu, void *cookie)
1216 tag->iommu_cookie = cookie;