2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 1997, 1998 Justin T. Gibbs.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions, and the following disclaimer,
12 * without modification, immediately at the beginning of the file.
13 * 2. The name of the author may not be used to endorse or promote products
14 * derived from this software without specific prior written permission.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
20 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * From amd64/busdma_machdep.c, r204214
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/malloc.h>
40 #include <sys/interrupt.h>
41 #include <sys/kernel.h>
45 #include <sys/memdesc.h>
46 #include <sys/mutex.h>
47 #include <sys/sysctl.h>
51 #include <vm/vm_extern.h>
52 #include <vm/vm_kern.h>
53 #include <vm/vm_page.h>
54 #include <vm/vm_map.h>
56 #include <machine/atomic.h>
57 #include <machine/bus.h>
58 #include <machine/cpufunc.h>
59 #include <machine/md_var.h>
63 #define MAX_BPAGES MIN(8192, physmem/40)
73 bus_dma_filter_t *filter;
81 bus_dma_lock_t *lockfunc;
83 struct bounce_zone *bounce_zone;
89 vm_offset_t vaddr; /* kva of bounce buffer */
90 bus_addr_t busaddr; /* Physical address */
91 vm_offset_t datavaddr; /* kva of client data */
92 vm_page_t datapage; /* physical page of client data */
93 vm_offset_t dataoffs; /* page offset of client data */
94 bus_size_t datacount; /* client data count */
95 STAILQ_ENTRY(bounce_page) links;
98 int busdma_swi_pending;
101 STAILQ_ENTRY(bounce_zone) links;
102 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
110 bus_size_t alignment;
114 struct sysctl_ctx_list sysctl_tree;
115 struct sysctl_oid *sysctl_tree_top;
118 static struct mtx bounce_lock;
119 static int total_bpages;
120 static int busdma_zonecount;
121 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
123 static SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
124 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
125 "Total bounce pages");
128 struct bp_list bpages;
133 bus_dma_segment_t *segments;
135 bus_dmamap_callback_t *callback;
137 STAILQ_ENTRY(bus_dmamap) links;
141 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
142 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
144 static void init_bounce_pages(void *dummy);
145 static int alloc_bounce_zone(bus_dma_tag_t dmat);
146 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
147 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
149 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
150 vm_offset_t vaddr, bus_addr_t addr,
152 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
153 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
156 * Return true if a match is made.
158 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'.
160 * If paddr is within the bounds of the dma tag then call the filter callback
161 * to check for a match, if there is no filter callback then assume a match.
164 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
171 if (dmat->filter == NULL && dmat->iommu == NULL &&
172 paddr > dmat->lowaddr && paddr <= dmat->highaddr)
174 if (dmat->filter == NULL &&
175 (paddr & (dmat->alignment - 1)) != 0)
177 if (dmat->filter != NULL &&
178 (*dmat->filter)(dmat->filterarg, paddr) != 0)
182 } while (retval == 0 && dmat != NULL);
187 * Convenience function for manipulating driver locks from busdma (during
188 * busdma_swi, for example). Drivers that don't provide their own locks
189 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own
190 * non-mutex locking scheme don't have to use this at all.
193 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
197 dmtx = (struct mtx *)arg;
206 panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
211 * dflt_lock should never get called. It gets put into the dma tag when
212 * lockfunc == NULL, which is only valid if the maps that are associated
213 * with the tag are meant to never be defered.
214 * XXX Should have a way to identify which driver is responsible here.
217 dflt_lock(void *arg, bus_dma_lock_op_t op)
219 panic("driver error: busdma dflt_lock called");
222 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
223 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
225 * Allocate a device specific dma_tag.
228 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
229 bus_addr_t boundary, bus_addr_t lowaddr,
230 bus_addr_t highaddr, bus_dma_filter_t *filter,
231 void *filterarg, bus_size_t maxsize, int nsegments,
232 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
233 void *lockfuncarg, bus_dma_tag_t *dmat)
235 bus_dma_tag_t newtag;
238 /* Basic sanity checking */
239 if (boundary != 0 && boundary < maxsegsz)
246 /* Return a NULL tag on failure */
249 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF,
251 if (newtag == NULL) {
252 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
253 __func__, newtag, 0, error);
257 newtag->parent = parent;
258 newtag->alignment = alignment;
259 newtag->boundary = boundary;
260 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
261 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
262 newtag->filter = filter;
263 newtag->filterarg = filterarg;
264 newtag->maxsize = maxsize;
265 newtag->nsegments = nsegments;
266 newtag->maxsegsz = maxsegsz;
267 newtag->flags = flags;
268 newtag->ref_count = 1; /* Count ourself */
269 newtag->map_count = 0;
270 if (lockfunc != NULL) {
271 newtag->lockfunc = lockfunc;
272 newtag->lockfuncarg = lockfuncarg;
274 newtag->lockfunc = dflt_lock;
275 newtag->lockfuncarg = NULL;
278 /* Take into account any restrictions imposed by our parent tag */
279 if (parent != NULL) {
280 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
281 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
282 if (newtag->boundary == 0)
283 newtag->boundary = parent->boundary;
284 else if (parent->boundary != 0)
285 newtag->boundary = MIN(parent->boundary,
287 if (newtag->filter == NULL) {
289 * Short circuit looking at our parent directly
290 * since we have encapsulated all of its information
292 newtag->filter = parent->filter;
293 newtag->filterarg = parent->filterarg;
294 newtag->parent = parent->parent;
296 if (newtag->parent != NULL)
297 atomic_add_int(&parent->ref_count, 1);
298 newtag->iommu = parent->iommu;
299 newtag->iommu_cookie = parent->iommu_cookie;
302 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) && newtag->iommu == NULL)
303 newtag->flags |= BUS_DMA_COULD_BOUNCE;
305 if (newtag->alignment > 1)
306 newtag->flags |= BUS_DMA_COULD_BOUNCE;
308 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
309 (flags & BUS_DMA_ALLOCNOW) != 0) {
310 struct bounce_zone *bz;
314 if ((error = alloc_bounce_zone(newtag)) != 0) {
315 free(newtag, M_DEVBUF);
318 bz = newtag->bounce_zone;
320 if (ptoa(bz->total_bpages) < maxsize) {
323 pages = atop(maxsize) - bz->total_bpages;
325 /* Add pages to our bounce pool */
326 if (alloc_bounce_pages(newtag, pages) < pages)
329 /* Performed initial allocation */
330 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
334 free(newtag, M_DEVBUF);
338 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
339 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
344 bus_dma_tag_set_domain(bus_dma_tag_t dmat, int domain)
351 bus_dma_tag_destroy(bus_dma_tag_t dmat)
353 bus_dma_tag_t dmat_copy;
361 if (dmat->map_count != 0) {
366 while (dmat != NULL) {
367 bus_dma_tag_t parent;
369 parent = dmat->parent;
370 atomic_subtract_int(&dmat->ref_count, 1);
371 if (dmat->ref_count == 0) {
372 free(dmat, M_DEVBUF);
374 * Last reference count, so
375 * release our reference
376 * count on our parent.
384 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
389 * Allocate a handle for mapping from kva/uva/physical
390 * address space into bus device space.
393 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
399 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
402 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
403 __func__, dmat, ENOMEM);
409 * Bouncing might be required if the driver asks for an active
410 * exclusion region, a data alignment that is stricter than 1, and/or
411 * an active address boundary.
413 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
416 struct bounce_zone *bz;
419 if (dmat->bounce_zone == NULL) {
420 if ((error = alloc_bounce_zone(dmat)) != 0)
423 bz = dmat->bounce_zone;
425 /* Initialize the new map */
426 STAILQ_INIT(&((*mapp)->bpages));
429 * Attempt to add pages to our pool on a per-instance
430 * basis up to a sane limit.
432 if (dmat->alignment > 1)
433 maxpages = MAX_BPAGES;
435 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
436 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
437 || (bz->map_count > 0 && bz->total_bpages < maxpages)) {
440 pages = MAX(atop(dmat->maxsize), 1);
441 pages = MIN(maxpages - bz->total_bpages, pages);
442 pages = MAX(pages, 1);
443 if (alloc_bounce_pages(dmat, pages) < pages)
446 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
448 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
457 (*mapp)->segments = (bus_dma_segment_t *)malloc(
458 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
460 if ((*mapp)->segments == NULL) {
461 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
462 __func__, dmat, ENOMEM);
468 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
469 __func__, dmat, dmat->flags, error);
474 * Destroy a handle for mapping from kva/uva/physical
475 * address space into bus device space.
478 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
480 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
481 if (STAILQ_FIRST(&map->bpages) != NULL) {
482 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
483 __func__, dmat, EBUSY);
486 if (dmat->bounce_zone)
487 dmat->bounce_zone->map_count--;
489 free(map->segments, M_DEVBUF);
492 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
498 * Allocate a piece of memory that can be efficiently mapped into
499 * bus device space based on the constraints lited in the dma tag.
500 * A dmamap to for use with dmamap_load is also allocated.
503 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
509 if (flags & BUS_DMA_NOWAIT)
514 bus_dmamap_create(dmat, flags, mapp);
516 if (flags & BUS_DMA_ZERO)
519 if (flags & BUS_DMA_NOCACHE)
520 attr = VM_MEMATTR_UNCACHEABLE;
523 attr = VM_MEMATTR_DEFAULT;
527 * (dmat->alignment <= dmat->maxsize) is just a quick hack; the exact
528 * alignment guarantees of malloc need to be nailed down, and the
529 * code below should be rewritten to take that into account.
531 * In the meantime, we'll warn the user if malloc gets it wrong.
533 if ((dmat->maxsize <= PAGE_SIZE) &&
534 (dmat->alignment <= dmat->maxsize) &&
535 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem) &&
536 attr == VM_MEMATTR_DEFAULT) {
537 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
540 * XXX Use Contigmalloc until it is merged into this facility
541 * and handles multi-seg allocations. Nobody is doing
542 * multi-seg allocations yet though.
543 * XXX Certain AGP hardware does.
545 *vaddr = (void *)kmem_alloc_contig(dmat->maxsize, mflags, 0ul,
546 dmat->lowaddr, dmat->alignment ? dmat->alignment : 1ul,
547 dmat->boundary, attr);
548 (*mapp)->contigalloc = 1;
550 if (*vaddr == NULL) {
551 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
552 __func__, dmat, dmat->flags, ENOMEM);
554 } else if (vtophys(*vaddr) & (dmat->alignment - 1)) {
555 printf("bus_dmamem_alloc failed to align memory properly.\n");
557 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
558 __func__, dmat, dmat->flags, 0);
563 * Free a piece of memory and it's allociated dmamap, that was allocated
564 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
567 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
570 if (!map->contigalloc)
571 free(vaddr, M_DEVBUF);
573 kmem_free((vm_offset_t)vaddr, dmat->maxsize);
574 bus_dmamap_destroy(dmat, map);
575 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
579 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf,
580 bus_size_t buflen, int flags)
585 if (map->pagesneeded == 0) {
586 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
587 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
588 dmat->boundary, dmat->alignment);
589 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map, map->pagesneeded);
591 * Count the number of bounce pages
592 * needed in order to complete this transfer
595 while (buflen != 0) {
596 sgsize = MIN(buflen, dmat->maxsegsz);
597 if (run_filter(dmat, curaddr) != 0) {
599 PAGE_SIZE - (curaddr & PAGE_MASK));
605 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
610 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap,
611 void *buf, bus_size_t buflen, int flags)
614 vm_offset_t vendaddr;
617 if (map->pagesneeded == 0) {
618 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
619 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
620 dmat->boundary, dmat->alignment);
621 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map, map->pagesneeded);
623 * Count the number of bounce pages
624 * needed in order to complete this transfer
626 vaddr = (vm_offset_t)buf;
627 vendaddr = (vm_offset_t)buf + buflen;
629 while (vaddr < vendaddr) {
632 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK);
633 if (pmap == kernel_pmap)
634 paddr = pmap_kextract(vaddr);
636 paddr = pmap_extract(pmap, vaddr);
637 if (run_filter(dmat, paddr) != 0) {
638 sg_len = roundup2(sg_len, dmat->alignment);
643 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
648 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags)
651 /* Reserve Necessary Bounce Pages */
652 mtx_lock(&bounce_lock);
653 if (flags & BUS_DMA_NOWAIT) {
654 if (reserve_bounce_pages(dmat, map, 0) != 0) {
655 mtx_unlock(&bounce_lock);
659 if (reserve_bounce_pages(dmat, map, 1) != 0) {
660 /* Queue us for resources */
661 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
663 mtx_unlock(&bounce_lock);
664 return (EINPROGRESS);
667 mtx_unlock(&bounce_lock);
673 * Add a single contiguous physical range to the segment list.
676 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, bus_addr_t curaddr,
677 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp)
679 bus_addr_t baddr, bmask;
683 * Make sure we don't cross any boundaries.
685 bmask = ~(dmat->boundary - 1);
686 if (dmat->boundary > 0) {
687 baddr = (curaddr + dmat->boundary) & bmask;
688 if (sgsize > (baddr - curaddr))
689 sgsize = (baddr - curaddr);
693 * Insert chunk into a segment, coalescing with
694 * previous segment if possible.
699 segs[seg].ds_addr = curaddr;
700 segs[seg].ds_len = sgsize;
702 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len &&
703 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
704 (dmat->boundary == 0 ||
705 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
706 segs[seg].ds_len += sgsize;
708 if (++seg >= dmat->nsegments)
710 segs[seg].ds_addr = curaddr;
711 segs[seg].ds_len = sgsize;
719 * Utility function to load a physical buffer. segp contains
720 * the starting segment on entrace, and the ending segment on exit.
723 _bus_dmamap_load_phys(bus_dma_tag_t dmat,
725 vm_paddr_t buf, bus_size_t buflen,
727 bus_dma_segment_t *segs,
735 segs = map->segments;
737 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
738 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags);
739 if (map->pagesneeded != 0) {
740 error = _bus_dmamap_reserve_pages(dmat, map, flags);
748 sgsize = MIN(buflen, dmat->maxsegsz);
749 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
750 sgsize = MIN(sgsize, PAGE_SIZE - (curaddr & PAGE_MASK));
751 curaddr = add_bounce_page(dmat, map, 0, curaddr,
754 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
765 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
769 _bus_dmamap_load_ma(bus_dma_tag_t dmat, bus_dmamap_t map,
770 struct vm_page **ma, bus_size_t tlen, int ma_offs, int flags,
771 bus_dma_segment_t *segs, int *segp)
774 return (bus_dmamap_load_ma_triv(dmat, map, ma, tlen, ma_offs, flags,
779 * Utility function to load a linear buffer. segp contains
780 * the starting segment on entrance, and the ending segment on exit.
783 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
785 void *buf, bus_size_t buflen,
788 bus_dma_segment_t *segs,
793 vm_offset_t kvaddr, vaddr;
797 segs = map->segments;
799 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
800 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags);
801 if (map->pagesneeded != 0) {
802 error = _bus_dmamap_reserve_pages(dmat, map, flags);
808 vaddr = (vm_offset_t)buf;
811 bus_size_t max_sgsize;
814 * Get the physical address for this segment.
816 if (pmap == kernel_pmap) {
817 curaddr = pmap_kextract(vaddr);
820 curaddr = pmap_extract(pmap, vaddr);
825 * Compute the segment size, and adjust counts.
827 max_sgsize = MIN(buflen, dmat->maxsegsz);
828 sgsize = PAGE_SIZE - (curaddr & PAGE_MASK);
829 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
830 sgsize = roundup2(sgsize, dmat->alignment);
831 sgsize = MIN(sgsize, max_sgsize);
832 curaddr = add_bounce_page(dmat, map, kvaddr, curaddr,
835 sgsize = MIN(sgsize, max_sgsize);
838 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
849 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
853 _bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map,
854 struct memdesc *mem, bus_dmamap_callback_t *callback,
858 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
861 map->callback = callback;
862 map->callback_arg = callback_arg;
867 _bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map,
868 bus_dma_segment_t *segs, int nsegs, int error)
873 memcpy(map->segments, segs, map->nsegs*sizeof(segs[0]));
874 if (dmat->iommu != NULL)
875 IOMMU_MAP(dmat->iommu, map->segments, &map->nsegs,
876 dmat->lowaddr, dmat->highaddr, dmat->alignment,
877 dmat->boundary, dmat->iommu_cookie);
880 memcpy(segs, map->segments, map->nsegs*sizeof(segs[0]));
882 segs = map->segments;
888 * Release the mapping held by map.
891 bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
893 struct bounce_page *bpage;
896 IOMMU_UNMAP(dmat->iommu, map->segments, map->nsegs, dmat->iommu_cookie);
900 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
901 STAILQ_REMOVE_HEAD(&map->bpages, links);
902 free_bounce_page(dmat, bpage);
907 bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
909 struct bounce_page *bpage;
910 vm_offset_t datavaddr, tempvaddr;
912 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
915 * Handle data bouncing. We might also
916 * want to add support for invalidating
917 * the caches on broken hardware
919 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
920 "performing bounce", __func__, dmat, dmat->flags, op);
922 if (op & BUS_DMASYNC_PREWRITE) {
923 while (bpage != NULL) {
925 datavaddr = bpage->datavaddr;
926 if (datavaddr == 0) {
927 tempvaddr = pmap_quick_enter_page(
929 datavaddr = tempvaddr |
933 bcopy((void *)datavaddr,
934 (void *)bpage->vaddr, bpage->datacount);
937 pmap_quick_remove_page(tempvaddr);
938 bpage = STAILQ_NEXT(bpage, links);
940 dmat->bounce_zone->total_bounced++;
943 if (op & BUS_DMASYNC_POSTREAD) {
944 while (bpage != NULL) {
946 datavaddr = bpage->datavaddr;
947 if (datavaddr == 0) {
948 tempvaddr = pmap_quick_enter_page(
950 datavaddr = tempvaddr |
954 bcopy((void *)bpage->vaddr,
955 (void *)datavaddr, bpage->datacount);
958 pmap_quick_remove_page(tempvaddr);
959 bpage = STAILQ_NEXT(bpage, links);
961 dmat->bounce_zone->total_bounced++;
969 init_bounce_pages(void *dummy __unused)
973 STAILQ_INIT(&bounce_zone_list);
974 STAILQ_INIT(&bounce_map_waitinglist);
975 STAILQ_INIT(&bounce_map_callbacklist);
976 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
978 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
980 static struct sysctl_ctx_list *
981 busdma_sysctl_tree(struct bounce_zone *bz)
983 return (&bz->sysctl_tree);
986 static struct sysctl_oid *
987 busdma_sysctl_tree_top(struct bounce_zone *bz)
989 return (bz->sysctl_tree_top);
993 alloc_bounce_zone(bus_dma_tag_t dmat)
995 struct bounce_zone *bz;
997 /* Check to see if we already have a suitable zone */
998 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
999 if ((dmat->alignment <= bz->alignment)
1000 && (dmat->lowaddr >= bz->lowaddr)) {
1001 dmat->bounce_zone = bz;
1006 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
1007 M_NOWAIT | M_ZERO)) == NULL)
1010 STAILQ_INIT(&bz->bounce_page_list);
1011 bz->free_bpages = 0;
1012 bz->reserved_bpages = 0;
1013 bz->active_bpages = 0;
1014 bz->lowaddr = dmat->lowaddr;
1015 bz->alignment = MAX(dmat->alignment, PAGE_SIZE);
1017 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
1019 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
1020 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
1021 dmat->bounce_zone = bz;
1023 sysctl_ctx_init(&bz->sysctl_tree);
1024 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
1025 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1027 if (bz->sysctl_tree_top == NULL) {
1028 sysctl_ctx_free(&bz->sysctl_tree);
1029 return (0); /* XXX error code? */
1032 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1033 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1034 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1035 "Total bounce pages");
1036 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1037 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1038 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1039 "Free bounce pages");
1040 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1041 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1042 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1043 "Reserved bounce pages");
1044 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1045 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1046 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1047 "Active bounce pages");
1048 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1049 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1050 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1051 "Total bounce requests");
1052 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1053 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1054 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1055 "Total bounce requests that were deferred");
1056 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1057 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1058 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1059 SYSCTL_ADD_UAUTO(busdma_sysctl_tree(bz),
1060 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1061 "alignment", CTLFLAG_RD, &bz->alignment, "");
1067 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1069 struct bounce_zone *bz;
1072 bz = dmat->bounce_zone;
1074 while (numpages > 0) {
1075 struct bounce_page *bpage;
1077 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1082 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1087 if (bpage->vaddr == 0) {
1088 free(bpage, M_DEVBUF);
1091 bpage->busaddr = pmap_kextract(bpage->vaddr);
1092 mtx_lock(&bounce_lock);
1093 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1097 mtx_unlock(&bounce_lock);
1105 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1107 struct bounce_zone *bz;
1110 mtx_assert(&bounce_lock, MA_OWNED);
1111 bz = dmat->bounce_zone;
1112 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1113 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1114 return (map->pagesneeded - (map->pagesreserved + pages));
1115 bz->free_bpages -= pages;
1116 bz->reserved_bpages += pages;
1117 map->pagesreserved += pages;
1118 pages = map->pagesneeded - map->pagesreserved;
1124 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1125 bus_addr_t addr, bus_size_t size)
1127 struct bounce_zone *bz;
1128 struct bounce_page *bpage;
1130 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1132 bz = dmat->bounce_zone;
1133 if (map->pagesneeded == 0)
1134 panic("add_bounce_page: map doesn't need any pages");
1137 if (map->pagesreserved == 0)
1138 panic("add_bounce_page: map doesn't need any pages");
1139 map->pagesreserved--;
1141 mtx_lock(&bounce_lock);
1142 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1144 panic("add_bounce_page: free page list is empty");
1146 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1147 bz->reserved_bpages--;
1148 bz->active_bpages++;
1149 mtx_unlock(&bounce_lock);
1151 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1152 /* Page offset needs to be preserved. */
1153 bpage->vaddr |= addr & PAGE_MASK;
1154 bpage->busaddr |= addr & PAGE_MASK;
1156 bpage->datavaddr = vaddr;
1157 bpage->datapage = PHYS_TO_VM_PAGE(addr);
1158 bpage->dataoffs = addr & PAGE_MASK;
1159 bpage->datacount = size;
1160 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1161 return (bpage->busaddr);
1165 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1167 struct bus_dmamap *map;
1168 struct bounce_zone *bz;
1170 bz = dmat->bounce_zone;
1171 bpage->datavaddr = 0;
1172 bpage->datacount = 0;
1173 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1175 * Reset the bounce page to start at offset 0. Other uses
1176 * of this bounce page may need to store a full page of
1177 * data and/or assume it starts on a page boundary.
1179 bpage->vaddr &= ~PAGE_MASK;
1180 bpage->busaddr &= ~PAGE_MASK;
1183 mtx_lock(&bounce_lock);
1184 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1186 bz->active_bpages--;
1187 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1188 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1189 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1190 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1192 busdma_swi_pending = 1;
1193 bz->total_deferred++;
1194 swi_sched(vm_ih, 0);
1197 mtx_unlock(&bounce_lock);
1204 struct bus_dmamap *map;
1206 mtx_lock(&bounce_lock);
1207 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1208 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1209 mtx_unlock(&bounce_lock);
1211 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1212 bus_dmamap_load_mem(map->dmat, map, &map->mem,
1213 map->callback, map->callback_arg,
1215 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1216 mtx_lock(&bounce_lock);
1218 mtx_unlock(&bounce_lock);
1222 bus_dma_tag_set_iommu(bus_dma_tag_t tag, device_t iommu, void *cookie)
1225 tag->iommu_cookie = cookie;