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
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include <sys/param.h>
33 #include <ddb/db_output.h>
34 #include <sys/systm.h>
35 #include <sys/malloc.h>
37 #include <sys/interrupt.h>
38 #include <sys/kernel.h>
42 #include <sys/mutex.h>
45 #include <sys/sysctl.h>
48 #include <vm/vm_page.h>
49 #include <vm/vm_map.h>
51 #include <machine/atomic.h>
52 #include <machine/bus.h>
53 #include <machine/md_var.h>
54 #include <machine/specialreg.h>
56 #define MAX_BPAGES 512
57 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
58 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
68 bus_dma_filter_t *filter;
76 bus_dma_lock_t *lockfunc;
78 bus_dma_segment_t *segments;
79 struct bounce_zone *bounce_zone;
83 vm_offset_t vaddr; /* kva of bounce buffer */
84 bus_addr_t busaddr; /* Physical address */
85 vm_offset_t datavaddr; /* kva of client data */
86 bus_size_t datacount; /* client data count */
87 STAILQ_ENTRY(bounce_page) links;
90 int busdma_swi_pending;
93 STAILQ_ENTRY(bounce_zone) links;
94 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
101 bus_size_t alignment;
106 struct sysctl_ctx_list sysctl_tree;
107 struct sysctl_oid *sysctl_tree_top;
110 static struct mtx bounce_lock;
111 static int total_bpages;
112 static int busdma_zonecount;
113 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
115 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
116 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
117 "Total bounce pages");
120 struct bp_list bpages;
124 void *buf; /* unmapped buffer pointer */
125 bus_size_t buflen; /* unmapped buffer length */
126 bus_dmamap_callback_t *callback;
128 STAILQ_ENTRY(bus_dmamap) links;
131 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
132 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
133 static struct bus_dmamap nobounce_dmamap;
135 static void init_bounce_pages(void *dummy);
136 static int alloc_bounce_zone(bus_dma_tag_t dmat);
137 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
138 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
140 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
141 vm_offset_t vaddr, bus_size_t size);
142 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
143 int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
144 int _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
145 bus_size_t buflen, int flags);
148 * Return true if a match is made.
150 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'.
152 * If paddr is within the bounds of the dma tag then call the filter callback
153 * to check for a match, if there is no filter callback then assume a match.
156 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
163 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr)
164 || ((paddr & (dmat->alignment - 1)) != 0))
165 && (dmat->filter == NULL
166 || (*dmat->filter)(dmat->filterarg, paddr) != 0))
170 } while (retval == 0 && dmat != NULL);
175 * Convenience function for manipulating driver locks from busdma (during
176 * busdma_swi, for example). Drivers that don't provide their own locks
177 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own
178 * non-mutex locking scheme don't have to use this at all.
181 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
185 dmtx = (struct mtx *)arg;
194 panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
199 * dflt_lock should never get called. It gets put into the dma tag when
200 * lockfunc == NULL, which is only valid if the maps that are associated
201 * with the tag are meant to never be defered.
202 * XXX Should have a way to identify which driver is responsible here.
205 dflt_lock(void *arg, bus_dma_lock_op_t op)
207 panic("driver error: busdma dflt_lock called");
211 * Allocate a device specific dma_tag.
214 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
215 bus_size_t boundary, bus_addr_t lowaddr,
216 bus_addr_t highaddr, bus_dma_filter_t *filter,
217 void *filterarg, bus_size_t maxsize, int nsegments,
218 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
219 void *lockfuncarg, bus_dma_tag_t *dmat)
221 bus_dma_tag_t newtag;
224 /* Basic sanity checking */
225 if (boundary != 0 && boundary < maxsegsz)
232 /* Return a NULL tag on failure */
235 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF,
237 if (newtag == NULL) {
238 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
239 __func__, newtag, 0, error);
243 newtag->parent = parent;
244 newtag->alignment = alignment;
245 newtag->boundary = boundary;
246 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
247 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) +
249 newtag->filter = filter;
250 newtag->filterarg = filterarg;
251 newtag->maxsize = maxsize;
252 newtag->nsegments = nsegments;
253 newtag->maxsegsz = maxsegsz;
254 newtag->flags = flags;
255 newtag->ref_count = 1; /* Count ourself */
256 newtag->map_count = 0;
257 if (lockfunc != NULL) {
258 newtag->lockfunc = lockfunc;
259 newtag->lockfuncarg = lockfuncarg;
261 newtag->lockfunc = dflt_lock;
262 newtag->lockfuncarg = NULL;
264 newtag->segments = NULL;
266 /* Take into account any restrictions imposed by our parent tag */
267 if (parent != NULL) {
268 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
269 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
270 if (newtag->boundary == 0)
271 newtag->boundary = parent->boundary;
272 else if (parent->boundary != 0)
273 newtag->boundary = MIN(parent->boundary,
275 if ((newtag->filter != NULL) ||
276 ((parent->flags & BUS_DMA_COULD_BOUNCE) != 0))
277 newtag->flags |= BUS_DMA_COULD_BOUNCE;
278 if (newtag->filter == NULL) {
280 * Short circuit looking at our parent directly
281 * since we have encapsulated all of its information
283 newtag->filter = parent->filter;
284 newtag->filterarg = parent->filterarg;
285 newtag->parent = parent->parent;
287 if (newtag->parent != NULL)
288 atomic_add_int(&parent->ref_count, 1);
291 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem)
292 || newtag->alignment > 1)
293 newtag->flags |= BUS_DMA_COULD_BOUNCE;
295 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
296 (flags & BUS_DMA_ALLOCNOW) != 0) {
297 struct bounce_zone *bz;
301 if ((error = alloc_bounce_zone(newtag)) != 0) {
302 free(newtag, M_DEVBUF);
305 bz = newtag->bounce_zone;
307 if (ptoa(bz->total_bpages) < maxsize) {
310 pages = atop(maxsize) - bz->total_bpages;
312 /* Add pages to our bounce pool */
313 if (alloc_bounce_pages(newtag, pages) < pages)
316 /* Performed initial allocation */
317 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
321 free(newtag, M_DEVBUF);
325 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
326 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
331 bus_dma_tag_destroy(bus_dma_tag_t dmat)
333 bus_dma_tag_t dmat_copy;
341 if (dmat->map_count != 0) {
346 while (dmat != NULL) {
347 bus_dma_tag_t parent;
349 parent = dmat->parent;
350 atomic_subtract_int(&dmat->ref_count, 1);
351 if (dmat->ref_count == 0) {
352 if (dmat->segments != NULL)
353 free(dmat->segments, M_DEVBUF);
354 free(dmat, M_DEVBUF);
356 * Last reference count, so
357 * release our reference
358 * count on our parent.
366 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
371 * Allocate a handle for mapping from kva/uva/physical
372 * address space into bus device space.
375 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
381 if (dmat->segments == NULL) {
382 dmat->segments = (bus_dma_segment_t *)malloc(
383 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
385 if (dmat->segments == NULL) {
386 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
387 __func__, dmat, ENOMEM);
393 * Bouncing might be required if the driver asks for an active
394 * exclusion region, a data alignment that is stricter than 1, and/or
395 * an active address boundary.
397 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
400 struct bounce_zone *bz;
403 if (dmat->bounce_zone == NULL) {
404 if ((error = alloc_bounce_zone(dmat)) != 0)
407 bz = dmat->bounce_zone;
409 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
412 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
413 __func__, dmat, ENOMEM);
417 /* Initialize the new map */
418 STAILQ_INIT(&((*mapp)->bpages));
421 * Attempt to add pages to our pool on a per-instance
422 * basis up to a sane limit.
424 if (dmat->alignment > 1)
425 maxpages = MAX_BPAGES;
427 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
428 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
429 || (dmat->map_count > 0 && bz->total_bpages < maxpages)) {
432 pages = MAX(atop(dmat->maxsize), 1);
433 pages = MIN(maxpages - bz->total_bpages, pages);
434 pages = MAX(pages, 1);
435 if (alloc_bounce_pages(dmat, pages) < pages)
438 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
440 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
450 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
451 __func__, dmat, dmat->flags, error);
456 * Destroy a handle for mapping from kva/uva/physical
457 * address space into bus device space.
460 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
462 if (map != NULL && map != &nobounce_dmamap) {
463 if (STAILQ_FIRST(&map->bpages) != NULL) {
464 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
465 __func__, dmat, EBUSY);
471 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
477 * Allocate a piece of memory that can be efficiently mapped into
478 * bus device space based on the constraints lited in the dma tag.
479 * A dmamap to for use with dmamap_load is also allocated.
482 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
487 if (flags & BUS_DMA_NOWAIT)
491 if (flags & BUS_DMA_ZERO)
494 /* If we succeed, no mapping/bouncing will be required */
497 if (dmat->segments == NULL) {
498 dmat->segments = (bus_dma_segment_t *)malloc(
499 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
501 if (dmat->segments == NULL) {
502 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
503 __func__, dmat, dmat->flags, ENOMEM);
510 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact
511 * alignment guarantees of malloc need to be nailed down, and the
512 * code below should be rewritten to take that into account.
514 * In the meantime, we'll warn the user if malloc gets it wrong.
516 if ((dmat->maxsize <= PAGE_SIZE) &&
517 (dmat->alignment < dmat->maxsize) &&
518 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) {
519 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
522 * XXX Use Contigmalloc until it is merged into this facility
523 * and handles multi-seg allocations. Nobody is doing
524 * multi-seg allocations yet though.
525 * XXX Certain AGP hardware does.
527 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
528 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
531 if (*vaddr == NULL) {
532 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
533 __func__, dmat, dmat->flags, ENOMEM);
535 } else if ((uintptr_t)*vaddr & (dmat->alignment - 1)) {
536 printf("bus_dmamem_alloc failed to align memory properly.\n");
538 if (flags & BUS_DMA_NOCACHE)
539 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize,
541 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
542 __func__, dmat, dmat->flags, ENOMEM);
547 * Free a piece of memory and it's allociated dmamap, that was allocated
548 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
551 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
554 * dmamem does not need to be bounced, so the map should be
558 panic("bus_dmamem_free: Invalid map freed\n");
559 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK);
560 if ((dmat->maxsize <= PAGE_SIZE) &&
561 (dmat->alignment < dmat->maxsize) &&
562 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem))
563 free(vaddr, M_DEVBUF);
565 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
567 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
571 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
572 bus_size_t buflen, int flags)
575 vm_offset_t vendaddr;
578 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) {
579 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
580 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
581 dmat->boundary, dmat->alignment);
582 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d",
583 map, &nobounce_dmamap, map->pagesneeded);
585 * Count the number of bounce pages
586 * needed in order to complete this transfer
588 vaddr = trunc_page((vm_offset_t)buf);
589 vendaddr = (vm_offset_t)buf + buflen;
591 while (vaddr < vendaddr) {
592 paddr = pmap_kextract(vaddr);
593 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
594 run_filter(dmat, paddr) != 0) {
599 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
602 /* Reserve Necessary Bounce Pages */
603 if (map->pagesneeded != 0) {
604 mtx_lock(&bounce_lock);
605 if (flags & BUS_DMA_NOWAIT) {
606 if (reserve_bounce_pages(dmat, map, 0) != 0) {
607 mtx_unlock(&bounce_lock);
611 if (reserve_bounce_pages(dmat, map, 1) != 0) {
612 /* Queue us for resources */
615 map->buflen = buflen;
616 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
618 mtx_unlock(&bounce_lock);
619 return (EINPROGRESS);
622 mtx_unlock(&bounce_lock);
629 * Utility function to load a linear buffer. lastaddrp holds state
630 * between invocations (for multiple-buffer loads). segp contains
631 * the starting segment on entrace, and the ending segment on exit.
632 * first indicates if this is the first invocation of this function.
635 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
637 void *buf, bus_size_t buflen,
640 bus_addr_t *lastaddrp,
641 bus_dma_segment_t *segs,
646 bus_addr_t curaddr, lastaddr, baddr, bmask;
651 map = &nobounce_dmamap;
653 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
654 error = _bus_dmamap_count_pages(dmat, map, buf, buflen, flags);
659 vaddr = (vm_offset_t)buf;
660 lastaddr = *lastaddrp;
661 bmask = ~(dmat->boundary - 1);
663 for (seg = *segp; buflen > 0 ; ) {
665 * Get the physical address for this segment.
668 curaddr = pmap_extract(pmap, vaddr);
670 curaddr = pmap_kextract(vaddr);
673 * Compute the segment size, and adjust counts.
675 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK);
676 if (sgsize > dmat->maxsegsz)
677 sgsize = dmat->maxsegsz;
682 * Make sure we don't cross any boundaries.
684 if (dmat->boundary > 0) {
685 baddr = (curaddr + dmat->boundary) & bmask;
686 if (sgsize > (baddr - curaddr))
687 sgsize = (baddr - curaddr);
690 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
691 map->pagesneeded != 0 && run_filter(dmat, curaddr))
692 curaddr = add_bounce_page(dmat, map, vaddr, sgsize);
695 * Insert chunk into a segment, coalescing with
696 * previous segment if possible.
699 segs[seg].ds_addr = curaddr;
700 segs[seg].ds_len = sgsize;
703 if (curaddr == lastaddr &&
704 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
705 (dmat->boundary == 0 ||
706 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
707 segs[seg].ds_len += sgsize;
709 if (++seg >= dmat->nsegments)
711 segs[seg].ds_addr = curaddr;
712 segs[seg].ds_len = sgsize;
716 lastaddr = curaddr + sgsize;
722 *lastaddrp = lastaddr;
727 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
731 * Map the buffer buf into bus space using the dmamap map.
734 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
735 bus_size_t buflen, bus_dmamap_callback_t *callback,
736 void *callback_arg, int flags)
738 bus_addr_t lastaddr = 0;
739 int error, nsegs = 0;
742 flags |= BUS_DMA_WAITOK;
743 map->callback = callback;
744 map->callback_arg = callback_arg;
747 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags,
748 &lastaddr, dmat->segments, &nsegs, 1);
750 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
751 __func__, dmat, dmat->flags, error, nsegs + 1);
753 if (error == EINPROGRESS) {
758 (*callback)(callback_arg, dmat->segments, 0, error);
760 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0);
763 * Return ENOMEM to the caller so that it can pass it up the stack.
764 * This error only happens when NOWAIT is set, so deferal is disabled.
774 * Like _bus_dmamap_load(), but for mbufs.
777 _bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map,
778 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs,
785 flags |= BUS_DMA_NOWAIT;
788 if (m0->m_pkthdr.len <= dmat->maxsize) {
790 bus_addr_t lastaddr = 0;
793 for (m = m0; m != NULL && error == 0; m = m->m_next) {
795 error = _bus_dmamap_load_buffer(dmat, map,
797 NULL, flags, &lastaddr,
806 /* XXX FIXME: Having to increment nsegs is really annoying */
808 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
809 __func__, dmat, dmat->flags, error, *nsegs);
814 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
816 bus_dmamap_callback2_t *callback, void *callback_arg,
821 error = _bus_dmamap_load_mbuf_sg(dmat, map, m0, dmat->segments, &nsegs,
825 /* force "no valid mappings" in callback */
826 (*callback)(callback_arg, dmat->segments, 0, 0, error);
828 (*callback)(callback_arg, dmat->segments,
829 nsegs, m0->m_pkthdr.len, error);
831 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
832 __func__, dmat, dmat->flags, error, nsegs);
837 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map,
838 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs,
841 return (_bus_dmamap_load_mbuf_sg(dmat, map, m0, segs, nsegs, flags));
845 * Like _bus_dmamap_load(), but for uios.
848 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
850 bus_dmamap_callback2_t *callback, void *callback_arg,
854 int nsegs, error, first, i;
859 flags |= BUS_DMA_NOWAIT;
860 resid = uio->uio_resid;
863 if (uio->uio_segflg == UIO_USERSPACE) {
864 KASSERT(uio->uio_td != NULL,
865 ("bus_dmamap_load_uio: USERSPACE but no proc"));
866 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace);
873 lastaddr = (bus_addr_t) 0;
874 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
876 * Now at the first iovec to load. Load each iovec
877 * until we have exhausted the residual count.
880 resid < iov[i].iov_len ? resid : iov[i].iov_len;
881 caddr_t addr = (caddr_t) iov[i].iov_base;
884 error = _bus_dmamap_load_buffer(dmat, map,
885 addr, minlen, pmap, flags, &lastaddr,
886 dmat->segments, &nsegs, first);
894 /* force "no valid mappings" in callback */
895 (*callback)(callback_arg, dmat->segments, 0, 0, error);
897 (*callback)(callback_arg, dmat->segments,
898 nsegs+1, uio->uio_resid, error);
900 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
901 __func__, dmat, dmat->flags, error, nsegs + 1);
906 * Release the mapping held by map.
909 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
911 struct bounce_page *bpage;
913 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
914 STAILQ_REMOVE_HEAD(&map->bpages, links);
915 free_bounce_page(dmat, bpage);
920 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
922 struct bounce_page *bpage;
924 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
926 * Handle data bouncing. We might also
927 * want to add support for invalidating
928 * the caches on broken hardware
930 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
931 "performing bounce", __func__, op, dmat, dmat->flags);
933 if (op & BUS_DMASYNC_PREWRITE) {
934 while (bpage != NULL) {
935 bcopy((void *)bpage->datavaddr,
936 (void *)bpage->vaddr,
938 bpage = STAILQ_NEXT(bpage, links);
940 dmat->bounce_zone->total_bounced++;
943 if (op & BUS_DMASYNC_POSTREAD) {
944 while (bpage != NULL) {
945 bcopy((void *)bpage->vaddr,
946 (void *)bpage->datavaddr,
948 bpage = STAILQ_NEXT(bpage, links);
950 dmat->bounce_zone->total_bounced++;
956 init_bounce_pages(void *dummy __unused)
960 STAILQ_INIT(&bounce_zone_list);
961 STAILQ_INIT(&bounce_map_waitinglist);
962 STAILQ_INIT(&bounce_map_callbacklist);
963 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
965 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
967 static struct sysctl_ctx_list *
968 busdma_sysctl_tree(struct bounce_zone *bz)
970 return (&bz->sysctl_tree);
973 static struct sysctl_oid *
974 busdma_sysctl_tree_top(struct bounce_zone *bz)
976 return (bz->sysctl_tree_top);
980 alloc_bounce_zone(bus_dma_tag_t dmat)
982 struct bounce_zone *bz;
984 /* Check to see if we already have a suitable zone */
985 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
986 if ((dmat->alignment <= bz->alignment)
987 && (dmat->boundary <= bz->boundary)
988 && (dmat->lowaddr >= bz->lowaddr)) {
989 dmat->bounce_zone = bz;
994 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
995 M_NOWAIT | M_ZERO)) == NULL)
998 STAILQ_INIT(&bz->bounce_page_list);
1000 bz->reserved_bpages = 0;
1001 bz->active_bpages = 0;
1002 bz->lowaddr = dmat->lowaddr;
1003 bz->alignment = dmat->alignment;
1004 bz->boundary = dmat->boundary;
1005 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
1007 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
1008 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
1009 dmat->bounce_zone = bz;
1011 sysctl_ctx_init(&bz->sysctl_tree);
1012 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
1013 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1015 if (bz->sysctl_tree_top == NULL) {
1016 sysctl_ctx_free(&bz->sysctl_tree);
1017 return (0); /* XXX error code? */
1020 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1021 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1022 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1023 "Total bounce pages");
1024 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1025 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1026 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1027 "Free bounce pages");
1028 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1029 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1030 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1031 "Reserved bounce pages");
1032 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1033 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1034 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1035 "Active bounce pages");
1036 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1037 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1038 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1039 "Total bounce requests");
1040 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1041 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1042 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1043 "Total bounce requests that were deferred");
1044 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1045 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1046 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1047 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1048 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1049 "alignment", CTLFLAG_RD, &bz->alignment, 0, "");
1050 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1051 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1052 "boundary", CTLFLAG_RD, &bz->boundary, 0, "");
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,
1118 struct bounce_zone *bz;
1119 struct bounce_page *bpage;
1121 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1122 KASSERT(map != NULL && map != &nobounce_dmamap,
1123 ("add_bounce_page: bad map %p", map));
1125 bz = dmat->bounce_zone;
1126 if (map->pagesneeded == 0)
1127 panic("add_bounce_page: map doesn't need any pages");
1130 if (map->pagesreserved == 0)
1131 panic("add_bounce_page: map doesn't need any pages");
1132 map->pagesreserved--;
1134 mtx_lock(&bounce_lock);
1135 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1137 panic("add_bounce_page: free page list is empty");
1139 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1140 bz->reserved_bpages--;
1141 bz->active_bpages++;
1142 mtx_unlock(&bounce_lock);
1144 bpage->datavaddr = vaddr;
1145 bpage->datacount = size;
1146 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1147 return (bpage->busaddr);
1151 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1153 struct bus_dmamap *map;
1154 struct bounce_zone *bz;
1156 bz = dmat->bounce_zone;
1157 bpage->datavaddr = 0;
1158 bpage->datacount = 0;
1160 mtx_lock(&bounce_lock);
1161 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1163 bz->active_bpages--;
1164 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1165 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1166 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1167 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1169 busdma_swi_pending = 1;
1170 bz->total_deferred++;
1171 swi_sched(vm_ih, 0);
1174 mtx_unlock(&bounce_lock);
1181 struct bus_dmamap *map;
1183 mtx_lock(&bounce_lock);
1184 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1185 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1186 mtx_unlock(&bounce_lock);
1188 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1189 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
1190 map->callback, map->callback_arg, /*flags*/0);
1191 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1192 mtx_lock(&bounce_lock);
1194 mtx_unlock(&bounce_lock);