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_clone(bus_dma_template_t *t, bus_dma_tag_t dmat)
348 if (t == NULL || dmat == NULL)
351 t->parent = dmat->parent;
352 t->alignment = dmat->alignment;
353 t->boundary = dmat->boundary;
354 t->lowaddr = dmat->lowaddr;
355 t->highaddr = dmat->highaddr;
356 t->maxsize = dmat->maxsize;
357 t->nsegments = dmat->nsegments;
358 t->maxsegsize = dmat->maxsegsz;
359 t->flags = dmat->flags;
360 t->lockfunc = dmat->lockfunc;
361 t->lockfuncarg = dmat->lockfuncarg;
365 bus_dma_tag_set_domain(bus_dma_tag_t dmat, int domain)
372 bus_dma_tag_destroy(bus_dma_tag_t dmat)
374 bus_dma_tag_t dmat_copy __unused;
381 if (dmat->map_count != 0) {
386 while (dmat != NULL) {
387 bus_dma_tag_t parent;
389 parent = dmat->parent;
390 atomic_subtract_int(&dmat->ref_count, 1);
391 if (dmat->ref_count == 0) {
392 free(dmat, M_DEVBUF);
394 * Last reference count, so
395 * release our reference
396 * count on our parent.
404 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
409 * Allocate a handle for mapping from kva/uva/physical
410 * address space into bus device space.
413 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
419 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
422 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
423 __func__, dmat, ENOMEM);
428 * Bouncing might be required if the driver asks for an active
429 * exclusion region, a data alignment that is stricter than 1, and/or
430 * an active address boundary.
432 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
434 struct bounce_zone *bz;
437 if (dmat->bounce_zone == NULL) {
438 if ((error = alloc_bounce_zone(dmat)) != 0)
441 bz = dmat->bounce_zone;
443 /* Initialize the new map */
444 STAILQ_INIT(&((*mapp)->bpages));
447 * Attempt to add pages to our pool on a per-instance
448 * basis up to a sane limit.
450 if (dmat->alignment > 1)
451 maxpages = MAX_BPAGES;
453 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
454 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
455 || (bz->map_count > 0 && bz->total_bpages < maxpages)) {
458 pages = MAX(atop(dmat->maxsize), 1);
459 pages = MIN(maxpages - bz->total_bpages, pages);
460 pages = MAX(pages, 1);
461 if (alloc_bounce_pages(dmat, pages) < pages)
464 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
466 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
475 (*mapp)->segments = (bus_dma_segment_t *)malloc(
476 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
478 if ((*mapp)->segments == NULL) {
479 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
480 __func__, dmat, ENOMEM);
486 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
487 __func__, dmat, dmat->flags, error);
492 * Destroy a handle for mapping from kva/uva/physical
493 * address space into bus device space.
496 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
498 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
499 if (STAILQ_FIRST(&map->bpages) != NULL) {
500 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
501 __func__, dmat, EBUSY);
504 if (dmat->bounce_zone)
505 dmat->bounce_zone->map_count--;
507 free(map->segments, M_DEVBUF);
510 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
515 * Allocate a piece of memory that can be efficiently mapped into
516 * bus device space based on the constraints lited in the dma tag.
517 * A dmamap to for use with dmamap_load is also allocated.
520 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
526 if (flags & BUS_DMA_NOWAIT)
531 bus_dmamap_create(dmat, flags, mapp);
533 if (flags & BUS_DMA_ZERO)
535 if (flags & BUS_DMA_NOCACHE)
536 attr = VM_MEMATTR_UNCACHEABLE;
538 attr = VM_MEMATTR_DEFAULT;
542 * (dmat->alignment <= dmat->maxsize) is just a quick hack; the exact
543 * alignment guarantees of malloc need to be nailed down, and the
544 * code below should be rewritten to take that into account.
546 * In the meantime, we'll warn the user if malloc gets it wrong.
548 if ((dmat->maxsize <= PAGE_SIZE) &&
549 (dmat->alignment <= dmat->maxsize) &&
550 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem) &&
551 attr == VM_MEMATTR_DEFAULT) {
552 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
555 * XXX Use Contigmalloc until it is merged into this facility
556 * and handles multi-seg allocations. Nobody is doing
557 * multi-seg allocations yet though.
558 * XXX Certain AGP hardware does.
560 *vaddr = (void *)kmem_alloc_contig(dmat->maxsize, mflags, 0ul,
561 dmat->lowaddr, dmat->alignment ? dmat->alignment : 1ul,
562 dmat->boundary, attr);
563 (*mapp)->contigalloc = 1;
565 if (*vaddr == NULL) {
566 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
567 __func__, dmat, dmat->flags, ENOMEM);
569 } else if (vtophys(*vaddr) & (dmat->alignment - 1)) {
570 printf("bus_dmamem_alloc failed to align memory properly.\n");
572 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
573 __func__, dmat, dmat->flags, 0);
578 * Free a piece of memory and it's allociated dmamap, that was allocated
579 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
582 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
585 if (!map->contigalloc)
586 free(vaddr, M_DEVBUF);
588 kmem_free((vm_offset_t)vaddr, dmat->maxsize);
589 bus_dmamap_destroy(dmat, map);
590 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
594 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf,
595 bus_size_t buflen, int flags)
600 if (map->pagesneeded == 0) {
601 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
602 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
603 dmat->boundary, dmat->alignment);
604 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map, map->pagesneeded);
606 * Count the number of bounce pages
607 * needed in order to complete this transfer
610 while (buflen != 0) {
611 sgsize = MIN(buflen, dmat->maxsegsz);
612 if (run_filter(dmat, curaddr) != 0) {
614 PAGE_SIZE - (curaddr & PAGE_MASK));
620 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
625 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap,
626 void *buf, bus_size_t buflen, int flags)
629 vm_offset_t vendaddr;
632 if (map->pagesneeded == 0) {
633 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
634 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
635 dmat->boundary, dmat->alignment);
636 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map, map->pagesneeded);
638 * Count the number of bounce pages
639 * needed in order to complete this transfer
641 vaddr = (vm_offset_t)buf;
642 vendaddr = (vm_offset_t)buf + buflen;
644 while (vaddr < vendaddr) {
647 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK);
648 if (pmap == kernel_pmap)
649 paddr = pmap_kextract(vaddr);
651 paddr = pmap_extract(pmap, vaddr);
652 if (run_filter(dmat, paddr) != 0) {
653 sg_len = roundup2(sg_len, dmat->alignment);
658 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
663 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags)
666 /* Reserve Necessary Bounce Pages */
667 mtx_lock(&bounce_lock);
668 if (flags & BUS_DMA_NOWAIT) {
669 if (reserve_bounce_pages(dmat, map, 0) != 0) {
670 mtx_unlock(&bounce_lock);
674 if (reserve_bounce_pages(dmat, map, 1) != 0) {
675 /* Queue us for resources */
676 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
678 mtx_unlock(&bounce_lock);
679 return (EINPROGRESS);
682 mtx_unlock(&bounce_lock);
688 * Add a single contiguous physical range to the segment list.
691 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, bus_addr_t curaddr,
692 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp)
694 bus_addr_t baddr, bmask;
698 * Make sure we don't cross any boundaries.
700 bmask = ~(dmat->boundary - 1);
701 if (dmat->boundary > 0) {
702 baddr = (curaddr + dmat->boundary) & bmask;
703 if (sgsize > (baddr - curaddr))
704 sgsize = (baddr - curaddr);
708 * Insert chunk into a segment, coalescing with
709 * previous segment if possible.
714 segs[seg].ds_addr = curaddr;
715 segs[seg].ds_len = sgsize;
717 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len &&
718 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
719 (dmat->boundary == 0 ||
720 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
721 segs[seg].ds_len += sgsize;
723 if (++seg >= dmat->nsegments)
725 segs[seg].ds_addr = curaddr;
726 segs[seg].ds_len = sgsize;
734 * Utility function to load a physical buffer. segp contains
735 * the starting segment on entrace, and the ending segment on exit.
738 _bus_dmamap_load_phys(bus_dma_tag_t dmat,
740 vm_paddr_t buf, bus_size_t buflen,
742 bus_dma_segment_t *segs,
750 segs = map->segments;
752 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
753 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags);
754 if (map->pagesneeded != 0) {
755 error = _bus_dmamap_reserve_pages(dmat, map, flags);
763 sgsize = MIN(buflen, dmat->maxsegsz);
764 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
765 sgsize = MIN(sgsize, PAGE_SIZE - (curaddr & PAGE_MASK));
766 curaddr = add_bounce_page(dmat, map, 0, curaddr,
769 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
780 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
784 _bus_dmamap_load_ma(bus_dma_tag_t dmat, bus_dmamap_t map,
785 struct vm_page **ma, bus_size_t tlen, int ma_offs, int flags,
786 bus_dma_segment_t *segs, int *segp)
789 return (bus_dmamap_load_ma_triv(dmat, map, ma, tlen, ma_offs, flags,
794 * Utility function to load a linear buffer. segp contains
795 * the starting segment on entrance, and the ending segment on exit.
798 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
800 void *buf, bus_size_t buflen,
803 bus_dma_segment_t *segs,
808 vm_offset_t kvaddr, vaddr;
812 segs = map->segments;
814 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
815 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags);
816 if (map->pagesneeded != 0) {
817 error = _bus_dmamap_reserve_pages(dmat, map, flags);
823 vaddr = (vm_offset_t)buf;
826 bus_size_t max_sgsize;
829 * Get the physical address for this segment.
831 if (pmap == kernel_pmap) {
832 curaddr = pmap_kextract(vaddr);
835 curaddr = pmap_extract(pmap, vaddr);
840 * Compute the segment size, and adjust counts.
842 max_sgsize = MIN(buflen, dmat->maxsegsz);
843 sgsize = PAGE_SIZE - (curaddr & PAGE_MASK);
844 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
845 sgsize = roundup2(sgsize, dmat->alignment);
846 sgsize = MIN(sgsize, max_sgsize);
847 curaddr = add_bounce_page(dmat, map, kvaddr, curaddr,
850 sgsize = MIN(sgsize, max_sgsize);
853 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
864 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
868 _bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map,
869 struct memdesc *mem, bus_dmamap_callback_t *callback,
873 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
876 map->callback = callback;
877 map->callback_arg = callback_arg;
882 _bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map,
883 bus_dma_segment_t *segs, int nsegs, int error)
888 memcpy(map->segments, segs, map->nsegs*sizeof(segs[0]));
889 if (dmat->iommu != NULL)
890 IOMMU_MAP(dmat->iommu, map->segments, &map->nsegs,
891 dmat->lowaddr, dmat->highaddr, dmat->alignment,
892 dmat->boundary, dmat->iommu_cookie);
895 memcpy(segs, map->segments, map->nsegs*sizeof(segs[0]));
897 segs = map->segments;
903 * Release the mapping held by map.
906 bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
908 struct bounce_page *bpage;
911 IOMMU_UNMAP(dmat->iommu, map->segments, map->nsegs, dmat->iommu_cookie);
915 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
916 STAILQ_REMOVE_HEAD(&map->bpages, links);
917 free_bounce_page(dmat, bpage);
922 bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
924 struct bounce_page *bpage;
925 vm_offset_t datavaddr, tempvaddr;
927 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
929 * Handle data bouncing. We might also
930 * want to add support for invalidating
931 * the caches on broken hardware
933 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
934 "performing bounce", __func__, dmat, dmat->flags, op);
936 if (op & BUS_DMASYNC_PREWRITE) {
937 while (bpage != NULL) {
939 datavaddr = bpage->datavaddr;
940 if (datavaddr == 0) {
941 tempvaddr = pmap_quick_enter_page(
943 datavaddr = tempvaddr |
947 bcopy((void *)datavaddr,
948 (void *)bpage->vaddr, bpage->datacount);
951 pmap_quick_remove_page(tempvaddr);
952 bpage = STAILQ_NEXT(bpage, links);
954 dmat->bounce_zone->total_bounced++;
957 if (op & BUS_DMASYNC_POSTREAD) {
958 while (bpage != NULL) {
960 datavaddr = bpage->datavaddr;
961 if (datavaddr == 0) {
962 tempvaddr = pmap_quick_enter_page(
964 datavaddr = tempvaddr |
968 bcopy((void *)bpage->vaddr,
969 (void *)datavaddr, bpage->datacount);
972 pmap_quick_remove_page(tempvaddr);
973 bpage = STAILQ_NEXT(bpage, links);
975 dmat->bounce_zone->total_bounced++;
983 init_bounce_pages(void *dummy __unused)
987 STAILQ_INIT(&bounce_zone_list);
988 STAILQ_INIT(&bounce_map_waitinglist);
989 STAILQ_INIT(&bounce_map_callbacklist);
990 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
992 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
994 static struct sysctl_ctx_list *
995 busdma_sysctl_tree(struct bounce_zone *bz)
997 return (&bz->sysctl_tree);
1000 static struct sysctl_oid *
1001 busdma_sysctl_tree_top(struct bounce_zone *bz)
1003 return (bz->sysctl_tree_top);
1007 alloc_bounce_zone(bus_dma_tag_t dmat)
1009 struct bounce_zone *bz;
1011 /* Check to see if we already have a suitable zone */
1012 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
1013 if ((dmat->alignment <= bz->alignment)
1014 && (dmat->lowaddr >= bz->lowaddr)) {
1015 dmat->bounce_zone = bz;
1020 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
1021 M_NOWAIT | M_ZERO)) == NULL)
1024 STAILQ_INIT(&bz->bounce_page_list);
1025 bz->free_bpages = 0;
1026 bz->reserved_bpages = 0;
1027 bz->active_bpages = 0;
1028 bz->lowaddr = dmat->lowaddr;
1029 bz->alignment = MAX(dmat->alignment, PAGE_SIZE);
1031 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
1033 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
1034 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
1035 dmat->bounce_zone = bz;
1037 sysctl_ctx_init(&bz->sysctl_tree);
1038 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
1039 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1040 CTLFLAG_RD | CTLFLAG_MPSAFE, 0, "");
1041 if (bz->sysctl_tree_top == NULL) {
1042 sysctl_ctx_free(&bz->sysctl_tree);
1043 return (0); /* XXX error code? */
1046 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1047 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1048 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1049 "Total bounce pages");
1050 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1051 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1052 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1053 "Free bounce pages");
1054 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1055 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1056 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1057 "Reserved bounce pages");
1058 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1059 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1060 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1061 "Active bounce pages");
1062 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1063 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1064 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1065 "Total bounce requests");
1066 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1067 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1068 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1069 "Total bounce requests that were deferred");
1070 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1071 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1072 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1073 SYSCTL_ADD_UAUTO(busdma_sysctl_tree(bz),
1074 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1075 "alignment", CTLFLAG_RD, &bz->alignment, "");
1081 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1083 struct bounce_zone *bz;
1086 bz = dmat->bounce_zone;
1088 while (numpages > 0) {
1089 struct bounce_page *bpage;
1091 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1096 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1101 if (bpage->vaddr == 0) {
1102 free(bpage, M_DEVBUF);
1105 bpage->busaddr = pmap_kextract(bpage->vaddr);
1106 mtx_lock(&bounce_lock);
1107 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1111 mtx_unlock(&bounce_lock);
1119 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1121 struct bounce_zone *bz;
1124 mtx_assert(&bounce_lock, MA_OWNED);
1125 bz = dmat->bounce_zone;
1126 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1127 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1128 return (map->pagesneeded - (map->pagesreserved + pages));
1129 bz->free_bpages -= pages;
1130 bz->reserved_bpages += pages;
1131 map->pagesreserved += pages;
1132 pages = map->pagesneeded - map->pagesreserved;
1138 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1139 bus_addr_t addr, bus_size_t size)
1141 struct bounce_zone *bz;
1142 struct bounce_page *bpage;
1144 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1146 bz = dmat->bounce_zone;
1147 if (map->pagesneeded == 0)
1148 panic("add_bounce_page: map doesn't need any pages");
1151 if (map->pagesreserved == 0)
1152 panic("add_bounce_page: map doesn't need any pages");
1153 map->pagesreserved--;
1155 mtx_lock(&bounce_lock);
1156 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1158 panic("add_bounce_page: free page list is empty");
1160 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1161 bz->reserved_bpages--;
1162 bz->active_bpages++;
1163 mtx_unlock(&bounce_lock);
1165 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1166 /* Page offset needs to be preserved. */
1167 bpage->vaddr |= addr & PAGE_MASK;
1168 bpage->busaddr |= addr & PAGE_MASK;
1170 bpage->datavaddr = vaddr;
1171 bpage->datapage = PHYS_TO_VM_PAGE(addr);
1172 bpage->dataoffs = addr & PAGE_MASK;
1173 bpage->datacount = size;
1174 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1175 return (bpage->busaddr);
1179 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1181 struct bus_dmamap *map;
1182 struct bounce_zone *bz;
1184 bz = dmat->bounce_zone;
1185 bpage->datavaddr = 0;
1186 bpage->datacount = 0;
1187 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1189 * Reset the bounce page to start at offset 0. Other uses
1190 * of this bounce page may need to store a full page of
1191 * data and/or assume it starts on a page boundary.
1193 bpage->vaddr &= ~PAGE_MASK;
1194 bpage->busaddr &= ~PAGE_MASK;
1197 mtx_lock(&bounce_lock);
1198 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1200 bz->active_bpages--;
1201 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1202 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1203 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1204 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1206 busdma_swi_pending = 1;
1207 bz->total_deferred++;
1208 swi_sched(vm_ih, 0);
1211 mtx_unlock(&bounce_lock);
1218 struct bus_dmamap *map;
1220 mtx_lock(&bounce_lock);
1221 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1222 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1223 mtx_unlock(&bounce_lock);
1225 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1226 bus_dmamap_load_mem(map->dmat, map, &map->mem,
1227 map->callback, map->callback_arg,
1229 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1230 mtx_lock(&bounce_lock);
1232 mtx_unlock(&bounce_lock);
1236 bus_dma_tag_set_iommu(bus_dma_tag_t tag, device_t iommu, void *cookie)
1239 tag->iommu_cookie = cookie;