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 | CTLFLAG_MPSAFE, 0,
124 "Busdma parameters");
125 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
126 "Total bounce pages");
129 struct bp_list bpages;
134 bus_dma_segment_t *segments;
136 bus_dmamap_callback_t *callback;
138 STAILQ_ENTRY(bus_dmamap) links;
142 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
143 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
145 static void init_bounce_pages(void *dummy);
146 static int alloc_bounce_zone(bus_dma_tag_t dmat);
147 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
148 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
150 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
151 vm_offset_t vaddr, bus_addr_t addr,
153 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
154 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
157 * Return true if a match is made.
159 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'.
161 * If paddr is within the bounds of the dma tag then call the filter callback
162 * to check for a match, if there is no filter callback then assume a match.
165 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
172 if (dmat->filter == NULL && dmat->iommu == NULL &&
173 paddr > dmat->lowaddr && paddr <= dmat->highaddr)
175 if (dmat->filter == NULL &&
176 (paddr & (dmat->alignment - 1)) != 0)
178 if (dmat->filter != NULL &&
179 (*dmat->filter)(dmat->filterarg, paddr) != 0)
183 } while (retval == 0 && dmat != NULL);
188 * Convenience function for manipulating driver locks from busdma (during
189 * busdma_swi, for example). Drivers that don't provide their own locks
190 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own
191 * non-mutex locking scheme don't have to use this at all.
194 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
198 dmtx = (struct mtx *)arg;
207 panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
212 * dflt_lock should never get called. It gets put into the dma tag when
213 * lockfunc == NULL, which is only valid if the maps that are associated
214 * with the tag are meant to never be defered.
215 * XXX Should have a way to identify which driver is responsible here.
218 dflt_lock(void *arg, bus_dma_lock_op_t op)
220 panic("driver error: busdma dflt_lock called");
223 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
224 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
226 * Allocate a device specific dma_tag.
229 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
230 bus_addr_t boundary, bus_addr_t lowaddr,
231 bus_addr_t highaddr, bus_dma_filter_t *filter,
232 void *filterarg, bus_size_t maxsize, int nsegments,
233 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
234 void *lockfuncarg, bus_dma_tag_t *dmat)
236 bus_dma_tag_t newtag;
239 /* Basic sanity checking */
240 if (boundary != 0 && boundary < maxsegsz)
247 /* Return a NULL tag on failure */
250 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF,
252 if (newtag == NULL) {
253 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
254 __func__, newtag, 0, error);
258 newtag->parent = parent;
259 newtag->alignment = alignment;
260 newtag->boundary = boundary;
261 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
262 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
263 newtag->filter = filter;
264 newtag->filterarg = filterarg;
265 newtag->maxsize = maxsize;
266 newtag->nsegments = nsegments;
267 newtag->maxsegsz = maxsegsz;
268 newtag->flags = flags;
269 newtag->ref_count = 1; /* Count ourself */
270 newtag->map_count = 0;
271 if (lockfunc != NULL) {
272 newtag->lockfunc = lockfunc;
273 newtag->lockfuncarg = lockfuncarg;
275 newtag->lockfunc = dflt_lock;
276 newtag->lockfuncarg = NULL;
279 /* Take into account any restrictions imposed by our parent tag */
280 if (parent != NULL) {
281 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
282 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
283 if (newtag->boundary == 0)
284 newtag->boundary = parent->boundary;
285 else if (parent->boundary != 0)
286 newtag->boundary = MIN(parent->boundary,
288 if (newtag->filter == NULL) {
290 * Short circuit looking at our parent directly
291 * since we have encapsulated all of its information
293 newtag->filter = parent->filter;
294 newtag->filterarg = parent->filterarg;
295 newtag->parent = parent->parent;
297 if (newtag->parent != NULL)
298 atomic_add_int(&parent->ref_count, 1);
299 newtag->iommu = parent->iommu;
300 newtag->iommu_cookie = parent->iommu_cookie;
303 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) && newtag->iommu == NULL)
304 newtag->flags |= BUS_DMA_COULD_BOUNCE;
306 if (newtag->alignment > 1)
307 newtag->flags |= BUS_DMA_COULD_BOUNCE;
309 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
310 (flags & BUS_DMA_ALLOCNOW) != 0) {
311 struct bounce_zone *bz;
315 if ((error = alloc_bounce_zone(newtag)) != 0) {
316 free(newtag, M_DEVBUF);
319 bz = newtag->bounce_zone;
321 if (ptoa(bz->total_bpages) < maxsize) {
324 pages = atop(maxsize) - bz->total_bpages;
326 /* Add pages to our bounce pool */
327 if (alloc_bounce_pages(newtag, pages) < pages)
330 /* Performed initial allocation */
331 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
335 free(newtag, M_DEVBUF);
339 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
340 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
345 bus_dma_template_init(bus_dma_tag_template_t *t, bus_dma_tag_t parent)
354 t->lowaddr = t->highaddr = BUS_SPACE_MAXADDR;
355 t->maxsize = t->maxsegsize = BUS_SPACE_MAXSIZE;
356 t->nsegments = BUS_SPACE_UNRESTRICTED;
358 t->lockfuncarg = NULL;
363 bus_dma_template_tag(bus_dma_tag_template_t *t, bus_dma_tag_t *dmat)
366 if (t == NULL || dmat == NULL)
369 return (bus_dma_tag_create(t->parent, t->alignment, t->boundary,
370 t->lowaddr, t->highaddr, NULL, NULL, t->maxsize,
371 t->nsegments, t->maxsegsize, t->flags, t->lockfunc, t->lockfuncarg,
376 bus_dma_template_clone(bus_dma_tag_template_t *t, bus_dma_tag_t dmat)
379 if (t == NULL || dmat == NULL)
382 t->parent = dmat->parent;
383 t->alignment = dmat->alignment;
384 t->boundary = dmat->boundary;
385 t->lowaddr = dmat->lowaddr;
386 t->highaddr = dmat->highaddr;
387 t->maxsize = dmat->maxsize;
388 t->nsegments = dmat->nsegments;
389 t->maxsegsize = dmat->maxsegsz;
390 t->flags = dmat->flags;
391 t->lockfunc = dmat->lockfunc;
392 t->lockfuncarg = dmat->lockfuncarg;
396 bus_dma_tag_set_domain(bus_dma_tag_t dmat, int domain)
403 bus_dma_tag_destroy(bus_dma_tag_t dmat)
405 bus_dma_tag_t dmat_copy __unused;
413 if (dmat->map_count != 0) {
418 while (dmat != NULL) {
419 bus_dma_tag_t parent;
421 parent = dmat->parent;
422 atomic_subtract_int(&dmat->ref_count, 1);
423 if (dmat->ref_count == 0) {
424 free(dmat, M_DEVBUF);
426 * Last reference count, so
427 * release our reference
428 * count on our parent.
436 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
441 * Allocate a handle for mapping from kva/uva/physical
442 * address space into bus device space.
445 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
451 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
454 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
455 __func__, dmat, ENOMEM);
461 * Bouncing might be required if the driver asks for an active
462 * exclusion region, a data alignment that is stricter than 1, and/or
463 * an active address boundary.
465 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
468 struct bounce_zone *bz;
471 if (dmat->bounce_zone == NULL) {
472 if ((error = alloc_bounce_zone(dmat)) != 0)
475 bz = dmat->bounce_zone;
477 /* Initialize the new map */
478 STAILQ_INIT(&((*mapp)->bpages));
481 * Attempt to add pages to our pool on a per-instance
482 * basis up to a sane limit.
484 if (dmat->alignment > 1)
485 maxpages = MAX_BPAGES;
487 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
488 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
489 || (bz->map_count > 0 && bz->total_bpages < maxpages)) {
492 pages = MAX(atop(dmat->maxsize), 1);
493 pages = MIN(maxpages - bz->total_bpages, pages);
494 pages = MAX(pages, 1);
495 if (alloc_bounce_pages(dmat, pages) < pages)
498 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
500 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
509 (*mapp)->segments = (bus_dma_segment_t *)malloc(
510 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
512 if ((*mapp)->segments == NULL) {
513 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
514 __func__, dmat, ENOMEM);
520 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
521 __func__, dmat, dmat->flags, error);
526 * Destroy a handle for mapping from kva/uva/physical
527 * address space into bus device space.
530 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
532 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
533 if (STAILQ_FIRST(&map->bpages) != NULL) {
534 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
535 __func__, dmat, EBUSY);
538 if (dmat->bounce_zone)
539 dmat->bounce_zone->map_count--;
541 free(map->segments, M_DEVBUF);
544 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
550 * Allocate a piece of memory that can be efficiently mapped into
551 * bus device space based on the constraints lited in the dma tag.
552 * A dmamap to for use with dmamap_load is also allocated.
555 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
561 if (flags & BUS_DMA_NOWAIT)
566 bus_dmamap_create(dmat, flags, mapp);
568 if (flags & BUS_DMA_ZERO)
570 if (flags & BUS_DMA_NOCACHE)
571 attr = VM_MEMATTR_UNCACHEABLE;
573 attr = VM_MEMATTR_DEFAULT;
577 * (dmat->alignment <= dmat->maxsize) is just a quick hack; the exact
578 * alignment guarantees of malloc need to be nailed down, and the
579 * code below should be rewritten to take that into account.
581 * In the meantime, we'll warn the user if malloc gets it wrong.
583 if ((dmat->maxsize <= PAGE_SIZE) &&
584 (dmat->alignment <= dmat->maxsize) &&
585 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem) &&
586 attr == VM_MEMATTR_DEFAULT) {
587 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
590 * XXX Use Contigmalloc until it is merged into this facility
591 * and handles multi-seg allocations. Nobody is doing
592 * multi-seg allocations yet though.
593 * XXX Certain AGP hardware does.
595 *vaddr = (void *)kmem_alloc_contig(dmat->maxsize, mflags, 0ul,
596 dmat->lowaddr, dmat->alignment ? dmat->alignment : 1ul,
597 dmat->boundary, attr);
598 (*mapp)->contigalloc = 1;
600 if (*vaddr == NULL) {
601 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
602 __func__, dmat, dmat->flags, ENOMEM);
604 } else if (vtophys(*vaddr) & (dmat->alignment - 1)) {
605 printf("bus_dmamem_alloc failed to align memory properly.\n");
607 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
608 __func__, dmat, dmat->flags, 0);
613 * Free a piece of memory and it's allociated dmamap, that was allocated
614 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
617 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
620 if (!map->contigalloc)
621 free(vaddr, M_DEVBUF);
623 kmem_free((vm_offset_t)vaddr, dmat->maxsize);
624 bus_dmamap_destroy(dmat, map);
625 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
629 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf,
630 bus_size_t buflen, int flags)
635 if (map->pagesneeded == 0) {
636 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
637 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
638 dmat->boundary, dmat->alignment);
639 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map, map->pagesneeded);
641 * Count the number of bounce pages
642 * needed in order to complete this transfer
645 while (buflen != 0) {
646 sgsize = MIN(buflen, dmat->maxsegsz);
647 if (run_filter(dmat, curaddr) != 0) {
649 PAGE_SIZE - (curaddr & PAGE_MASK));
655 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
660 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap,
661 void *buf, bus_size_t buflen, int flags)
664 vm_offset_t vendaddr;
667 if (map->pagesneeded == 0) {
668 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
669 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
670 dmat->boundary, dmat->alignment);
671 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map, map->pagesneeded);
673 * Count the number of bounce pages
674 * needed in order to complete this transfer
676 vaddr = (vm_offset_t)buf;
677 vendaddr = (vm_offset_t)buf + buflen;
679 while (vaddr < vendaddr) {
682 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK);
683 if (pmap == kernel_pmap)
684 paddr = pmap_kextract(vaddr);
686 paddr = pmap_extract(pmap, vaddr);
687 if (run_filter(dmat, paddr) != 0) {
688 sg_len = roundup2(sg_len, dmat->alignment);
693 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
698 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags)
701 /* Reserve Necessary Bounce Pages */
702 mtx_lock(&bounce_lock);
703 if (flags & BUS_DMA_NOWAIT) {
704 if (reserve_bounce_pages(dmat, map, 0) != 0) {
705 mtx_unlock(&bounce_lock);
709 if (reserve_bounce_pages(dmat, map, 1) != 0) {
710 /* Queue us for resources */
711 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
713 mtx_unlock(&bounce_lock);
714 return (EINPROGRESS);
717 mtx_unlock(&bounce_lock);
723 * Add a single contiguous physical range to the segment list.
726 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, bus_addr_t curaddr,
727 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp)
729 bus_addr_t baddr, bmask;
733 * Make sure we don't cross any boundaries.
735 bmask = ~(dmat->boundary - 1);
736 if (dmat->boundary > 0) {
737 baddr = (curaddr + dmat->boundary) & bmask;
738 if (sgsize > (baddr - curaddr))
739 sgsize = (baddr - curaddr);
743 * Insert chunk into a segment, coalescing with
744 * previous segment if possible.
749 segs[seg].ds_addr = curaddr;
750 segs[seg].ds_len = sgsize;
752 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len &&
753 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
754 (dmat->boundary == 0 ||
755 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
756 segs[seg].ds_len += sgsize;
758 if (++seg >= dmat->nsegments)
760 segs[seg].ds_addr = curaddr;
761 segs[seg].ds_len = sgsize;
769 * Utility function to load a physical buffer. segp contains
770 * the starting segment on entrace, and the ending segment on exit.
773 _bus_dmamap_load_phys(bus_dma_tag_t dmat,
775 vm_paddr_t buf, bus_size_t buflen,
777 bus_dma_segment_t *segs,
785 segs = map->segments;
787 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
788 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags);
789 if (map->pagesneeded != 0) {
790 error = _bus_dmamap_reserve_pages(dmat, map, flags);
798 sgsize = MIN(buflen, dmat->maxsegsz);
799 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
800 sgsize = MIN(sgsize, PAGE_SIZE - (curaddr & PAGE_MASK));
801 curaddr = add_bounce_page(dmat, map, 0, curaddr,
804 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
815 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
819 _bus_dmamap_load_ma(bus_dma_tag_t dmat, bus_dmamap_t map,
820 struct vm_page **ma, bus_size_t tlen, int ma_offs, int flags,
821 bus_dma_segment_t *segs, int *segp)
824 return (bus_dmamap_load_ma_triv(dmat, map, ma, tlen, ma_offs, flags,
829 * Utility function to load a linear buffer. segp contains
830 * the starting segment on entrance, and the ending segment on exit.
833 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
835 void *buf, bus_size_t buflen,
838 bus_dma_segment_t *segs,
843 vm_offset_t kvaddr, vaddr;
847 segs = map->segments;
849 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
850 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags);
851 if (map->pagesneeded != 0) {
852 error = _bus_dmamap_reserve_pages(dmat, map, flags);
858 vaddr = (vm_offset_t)buf;
861 bus_size_t max_sgsize;
864 * Get the physical address for this segment.
866 if (pmap == kernel_pmap) {
867 curaddr = pmap_kextract(vaddr);
870 curaddr = pmap_extract(pmap, vaddr);
875 * Compute the segment size, and adjust counts.
877 max_sgsize = MIN(buflen, dmat->maxsegsz);
878 sgsize = PAGE_SIZE - (curaddr & PAGE_MASK);
879 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
880 sgsize = roundup2(sgsize, dmat->alignment);
881 sgsize = MIN(sgsize, max_sgsize);
882 curaddr = add_bounce_page(dmat, map, kvaddr, curaddr,
885 sgsize = MIN(sgsize, max_sgsize);
888 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
899 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
903 _bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map,
904 struct memdesc *mem, bus_dmamap_callback_t *callback,
908 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
911 map->callback = callback;
912 map->callback_arg = callback_arg;
917 _bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map,
918 bus_dma_segment_t *segs, int nsegs, int error)
923 memcpy(map->segments, segs, map->nsegs*sizeof(segs[0]));
924 if (dmat->iommu != NULL)
925 IOMMU_MAP(dmat->iommu, map->segments, &map->nsegs,
926 dmat->lowaddr, dmat->highaddr, dmat->alignment,
927 dmat->boundary, dmat->iommu_cookie);
930 memcpy(segs, map->segments, map->nsegs*sizeof(segs[0]));
932 segs = map->segments;
938 * Release the mapping held by map.
941 bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
943 struct bounce_page *bpage;
946 IOMMU_UNMAP(dmat->iommu, map->segments, map->nsegs, dmat->iommu_cookie);
950 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
951 STAILQ_REMOVE_HEAD(&map->bpages, links);
952 free_bounce_page(dmat, bpage);
957 bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
959 struct bounce_page *bpage;
960 vm_offset_t datavaddr, tempvaddr;
962 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
965 * Handle data bouncing. We might also
966 * want to add support for invalidating
967 * the caches on broken hardware
969 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
970 "performing bounce", __func__, dmat, dmat->flags, op);
972 if (op & BUS_DMASYNC_PREWRITE) {
973 while (bpage != NULL) {
975 datavaddr = bpage->datavaddr;
976 if (datavaddr == 0) {
977 tempvaddr = pmap_quick_enter_page(
979 datavaddr = tempvaddr |
983 bcopy((void *)datavaddr,
984 (void *)bpage->vaddr, bpage->datacount);
987 pmap_quick_remove_page(tempvaddr);
988 bpage = STAILQ_NEXT(bpage, links);
990 dmat->bounce_zone->total_bounced++;
993 if (op & BUS_DMASYNC_POSTREAD) {
994 while (bpage != NULL) {
996 datavaddr = bpage->datavaddr;
997 if (datavaddr == 0) {
998 tempvaddr = pmap_quick_enter_page(
1000 datavaddr = tempvaddr |
1004 bcopy((void *)bpage->vaddr,
1005 (void *)datavaddr, bpage->datacount);
1008 pmap_quick_remove_page(tempvaddr);
1009 bpage = STAILQ_NEXT(bpage, links);
1011 dmat->bounce_zone->total_bounced++;
1019 init_bounce_pages(void *dummy __unused)
1023 STAILQ_INIT(&bounce_zone_list);
1024 STAILQ_INIT(&bounce_map_waitinglist);
1025 STAILQ_INIT(&bounce_map_callbacklist);
1026 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
1028 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
1030 static struct sysctl_ctx_list *
1031 busdma_sysctl_tree(struct bounce_zone *bz)
1033 return (&bz->sysctl_tree);
1036 static struct sysctl_oid *
1037 busdma_sysctl_tree_top(struct bounce_zone *bz)
1039 return (bz->sysctl_tree_top);
1043 alloc_bounce_zone(bus_dma_tag_t dmat)
1045 struct bounce_zone *bz;
1047 /* Check to see if we already have a suitable zone */
1048 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
1049 if ((dmat->alignment <= bz->alignment)
1050 && (dmat->lowaddr >= bz->lowaddr)) {
1051 dmat->bounce_zone = bz;
1056 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
1057 M_NOWAIT | M_ZERO)) == NULL)
1060 STAILQ_INIT(&bz->bounce_page_list);
1061 bz->free_bpages = 0;
1062 bz->reserved_bpages = 0;
1063 bz->active_bpages = 0;
1064 bz->lowaddr = dmat->lowaddr;
1065 bz->alignment = MAX(dmat->alignment, PAGE_SIZE);
1067 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
1069 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
1070 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
1071 dmat->bounce_zone = bz;
1073 sysctl_ctx_init(&bz->sysctl_tree);
1074 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
1075 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1076 CTLFLAG_RD | CTLFLAG_MPSAFE, 0, "");
1077 if (bz->sysctl_tree_top == NULL) {
1078 sysctl_ctx_free(&bz->sysctl_tree);
1079 return (0); /* XXX error code? */
1082 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1083 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1084 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1085 "Total bounce pages");
1086 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1087 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1088 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1089 "Free bounce pages");
1090 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1091 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1092 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1093 "Reserved bounce pages");
1094 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1095 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1096 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1097 "Active bounce pages");
1098 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1099 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1100 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1101 "Total bounce requests");
1102 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1103 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1104 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1105 "Total bounce requests that were deferred");
1106 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1107 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1108 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1109 SYSCTL_ADD_UAUTO(busdma_sysctl_tree(bz),
1110 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1111 "alignment", CTLFLAG_RD, &bz->alignment, "");
1117 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1119 struct bounce_zone *bz;
1122 bz = dmat->bounce_zone;
1124 while (numpages > 0) {
1125 struct bounce_page *bpage;
1127 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1132 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1137 if (bpage->vaddr == 0) {
1138 free(bpage, M_DEVBUF);
1141 bpage->busaddr = pmap_kextract(bpage->vaddr);
1142 mtx_lock(&bounce_lock);
1143 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1147 mtx_unlock(&bounce_lock);
1155 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1157 struct bounce_zone *bz;
1160 mtx_assert(&bounce_lock, MA_OWNED);
1161 bz = dmat->bounce_zone;
1162 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1163 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1164 return (map->pagesneeded - (map->pagesreserved + pages));
1165 bz->free_bpages -= pages;
1166 bz->reserved_bpages += pages;
1167 map->pagesreserved += pages;
1168 pages = map->pagesneeded - map->pagesreserved;
1174 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1175 bus_addr_t addr, bus_size_t size)
1177 struct bounce_zone *bz;
1178 struct bounce_page *bpage;
1180 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1182 bz = dmat->bounce_zone;
1183 if (map->pagesneeded == 0)
1184 panic("add_bounce_page: map doesn't need any pages");
1187 if (map->pagesreserved == 0)
1188 panic("add_bounce_page: map doesn't need any pages");
1189 map->pagesreserved--;
1191 mtx_lock(&bounce_lock);
1192 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1194 panic("add_bounce_page: free page list is empty");
1196 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1197 bz->reserved_bpages--;
1198 bz->active_bpages++;
1199 mtx_unlock(&bounce_lock);
1201 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1202 /* Page offset needs to be preserved. */
1203 bpage->vaddr |= addr & PAGE_MASK;
1204 bpage->busaddr |= addr & PAGE_MASK;
1206 bpage->datavaddr = vaddr;
1207 bpage->datapage = PHYS_TO_VM_PAGE(addr);
1208 bpage->dataoffs = addr & PAGE_MASK;
1209 bpage->datacount = size;
1210 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1211 return (bpage->busaddr);
1215 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1217 struct bus_dmamap *map;
1218 struct bounce_zone *bz;
1220 bz = dmat->bounce_zone;
1221 bpage->datavaddr = 0;
1222 bpage->datacount = 0;
1223 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1225 * Reset the bounce page to start at offset 0. Other uses
1226 * of this bounce page may need to store a full page of
1227 * data and/or assume it starts on a page boundary.
1229 bpage->vaddr &= ~PAGE_MASK;
1230 bpage->busaddr &= ~PAGE_MASK;
1233 mtx_lock(&bounce_lock);
1234 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1236 bz->active_bpages--;
1237 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1238 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1239 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1240 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1242 busdma_swi_pending = 1;
1243 bz->total_deferred++;
1244 swi_sched(vm_ih, 0);
1247 mtx_unlock(&bounce_lock);
1254 struct bus_dmamap *map;
1256 mtx_lock(&bounce_lock);
1257 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1258 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1259 mtx_unlock(&bounce_lock);
1261 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1262 bus_dmamap_load_mem(map->dmat, map, &map->mem,
1263 map->callback, map->callback_arg,
1265 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1266 mtx_lock(&bounce_lock);
1268 mtx_unlock(&bounce_lock);
1272 bus_dma_tag_set_iommu(bus_dma_tag_t tag, device_t iommu, void *cookie)
1275 tag->iommu_cookie = cookie;