2 * Copyright (c) 1997, 1998 Justin T. Gibbs.
3 * Copyright (c) 2015 The FreeBSD Foundation
6 * Portions of this software were developed by Semihalf
7 * under sponsorship of the FreeBSD Foundation.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions, and the following disclaimer,
14 * without modification, immediately at the beginning of the file.
15 * 2. The name of the author may not be used to endorse or promote products
16 * derived from this software without specific prior written permission.
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
22 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/malloc.h>
38 #include <sys/interrupt.h>
39 #include <sys/kernel.h>
43 #include <sys/memdesc.h>
44 #include <sys/mutex.h>
45 #include <sys/sysctl.h>
49 #include <vm/vm_extern.h>
50 #include <vm/vm_kern.h>
51 #include <vm/vm_page.h>
52 #include <vm/vm_map.h>
54 #include <machine/atomic.h>
55 #include <machine/bus.h>
56 #include <machine/md_var.h>
57 #include <arm64/include/bus_dma_impl.h>
59 #define MAX_BPAGES 4096
62 BUS_DMA_COULD_BOUNCE = 0x01,
63 BUS_DMA_MIN_ALLOC_COMP = 0x02,
64 BUS_DMA_KMEM_ALLOC = 0x04,
70 struct bus_dma_tag_common common;
73 bus_dma_segment_t *segments;
74 struct bounce_zone *bounce_zone;
78 vm_offset_t vaddr; /* kva of bounce buffer */
79 bus_addr_t busaddr; /* Physical address */
80 vm_offset_t datavaddr; /* kva of client data */
81 bus_addr_t dataaddr; /* client physical address */
82 bus_size_t datacount; /* client data count */
83 STAILQ_ENTRY(bounce_page) links;
86 int busdma_swi_pending;
89 STAILQ_ENTRY(bounce_zone) links;
90 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
102 struct sysctl_ctx_list sysctl_tree;
103 struct sysctl_oid *sysctl_tree_top;
106 static struct mtx bounce_lock;
107 static int total_bpages;
108 static int busdma_zonecount;
109 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
111 static SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
112 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
113 "Total bounce pages");
116 struct bp_list bpages;
121 bus_dmamap_callback_t *callback;
123 STAILQ_ENTRY(bus_dmamap) links;
126 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
127 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
128 static struct bus_dmamap nobounce_dmamap;
130 static void init_bounce_pages(void *dummy);
131 static int alloc_bounce_zone(bus_dma_tag_t dmat);
132 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
133 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
135 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
136 vm_offset_t vaddr, bus_addr_t addr, bus_size_t size);
137 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
138 int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
139 static void _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
140 pmap_t pmap, void *buf, bus_size_t buflen, int flags);
141 static void _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map,
142 vm_paddr_t buf, bus_size_t buflen, int flags);
143 static int _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
147 * Allocate a device specific dma_tag.
150 bounce_bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
151 bus_addr_t boundary, bus_addr_t lowaddr, bus_addr_t highaddr,
152 bus_dma_filter_t *filter, void *filterarg, bus_size_t maxsize,
153 int nsegments, bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
154 void *lockfuncarg, bus_dma_tag_t *dmat)
156 bus_dma_tag_t newtag;
160 error = common_bus_dma_tag_create(parent != NULL ? &parent->common :
161 NULL, alignment, boundary, lowaddr, highaddr, filter, filterarg,
162 maxsize, nsegments, maxsegsz, flags, lockfunc, lockfuncarg,
163 sizeof (struct bus_dma_tag), (void **)&newtag);
167 newtag->common.impl = &bus_dma_bounce_impl;
168 newtag->map_count = 0;
169 newtag->segments = NULL;
171 if (parent != NULL && ((newtag->common.filter != NULL) ||
172 ((parent->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0)))
173 newtag->bounce_flags |= BUS_DMA_COULD_BOUNCE;
175 if (newtag->common.lowaddr < ptoa((vm_paddr_t)Maxmem) ||
176 newtag->common.alignment > 1)
177 newtag->bounce_flags |= BUS_DMA_COULD_BOUNCE;
179 if (((newtag->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) &&
180 (flags & BUS_DMA_ALLOCNOW) != 0) {
181 struct bounce_zone *bz;
184 if ((error = alloc_bounce_zone(newtag)) != 0) {
185 free(newtag, M_DEVBUF);
188 bz = newtag->bounce_zone;
190 if (ptoa(bz->total_bpages) < maxsize) {
193 pages = atop(maxsize) - bz->total_bpages;
195 /* Add pages to our bounce pool */
196 if (alloc_bounce_pages(newtag, pages) < pages)
199 /* Performed initial allocation */
200 newtag->bounce_flags |= BUS_DMA_MIN_ALLOC_COMP;
205 free(newtag, M_DEVBUF);
208 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
209 __func__, newtag, (newtag != NULL ? newtag->common.flags : 0),
215 bounce_bus_dma_tag_destroy(bus_dma_tag_t dmat)
217 bus_dma_tag_t dmat_copy, parent;
224 if (dmat->map_count != 0) {
228 while (dmat != NULL) {
229 parent = (bus_dma_tag_t)dmat->common.parent;
230 atomic_subtract_int(&dmat->common.ref_count, 1);
231 if (dmat->common.ref_count == 0) {
232 if (dmat->segments != NULL)
233 free(dmat->segments, M_DEVBUF);
234 free(dmat, M_DEVBUF);
236 * Last reference count, so
237 * release our reference
238 * count on our parent.
246 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
251 * Allocate a handle for mapping from kva/uva/physical
252 * address space into bus device space.
255 bounce_bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
257 struct bounce_zone *bz;
258 int error, maxpages, pages;
262 if (dmat->segments == NULL) {
263 dmat->segments = (bus_dma_segment_t *)malloc(
264 sizeof(bus_dma_segment_t) * dmat->common.nsegments,
266 if (dmat->segments == NULL) {
267 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
268 __func__, dmat, ENOMEM);
274 * Bouncing might be required if the driver asks for an active
275 * exclusion region, a data alignment that is stricter than 1, and/or
276 * an active address boundary.
278 if (dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) {
280 if (dmat->bounce_zone == NULL) {
281 if ((error = alloc_bounce_zone(dmat)) != 0)
284 bz = dmat->bounce_zone;
286 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
289 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
290 __func__, dmat, ENOMEM);
294 /* Initialize the new map */
295 STAILQ_INIT(&((*mapp)->bpages));
298 * Attempt to add pages to our pool on a per-instance
299 * basis up to a sane limit.
301 if (dmat->common.alignment > 1)
302 maxpages = MAX_BPAGES;
304 maxpages = MIN(MAX_BPAGES, Maxmem -
305 atop(dmat->common.lowaddr));
306 if ((dmat->bounce_flags & BUS_DMA_MIN_ALLOC_COMP) == 0 ||
307 (bz->map_count > 0 && bz->total_bpages < maxpages)) {
308 pages = MAX(atop(dmat->common.maxsize), 1);
309 pages = MIN(maxpages - bz->total_bpages, pages);
310 pages = MAX(pages, 1);
311 if (alloc_bounce_pages(dmat, pages) < pages)
313 if ((dmat->bounce_flags & BUS_DMA_MIN_ALLOC_COMP)
316 dmat->bounce_flags |=
317 BUS_DMA_MIN_ALLOC_COMP;
328 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
329 __func__, dmat, dmat->common.flags, error);
334 * Destroy a handle for mapping from kva/uva/physical
335 * address space into bus device space.
338 bounce_bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
341 if (map != NULL && map != &nobounce_dmamap) {
342 if (STAILQ_FIRST(&map->bpages) != NULL) {
343 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
344 __func__, dmat, EBUSY);
347 if (dmat->bounce_zone)
348 dmat->bounce_zone->map_count--;
352 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
358 * Allocate a piece of memory that can be efficiently mapped into
359 * bus device space based on the constraints lited in the dma tag.
360 * A dmamap to for use with dmamap_load is also allocated.
363 bounce_bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
368 * This bus_dma implementation requires IO-Coherent architecutre.
369 * If IO-Coherency is not guaranteed, the BUS_DMA_COHERENT flag has
370 * to be implented using non-cacheable memory.
376 if (flags & BUS_DMA_NOWAIT)
381 /* If we succeed, no mapping/bouncing will be required */
384 if (dmat->segments == NULL) {
385 dmat->segments = (bus_dma_segment_t *)malloc(
386 sizeof(bus_dma_segment_t) * dmat->common.nsegments,
388 if (dmat->segments == NULL) {
389 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
390 __func__, dmat, dmat->common.flags, ENOMEM);
394 if (flags & BUS_DMA_ZERO)
396 if (flags & BUS_DMA_NOCACHE)
397 attr = VM_MEMATTR_UNCACHEABLE;
399 attr = VM_MEMATTR_DEFAULT;
403 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact
404 * alignment guarantees of malloc need to be nailed down, and the
405 * code below should be rewritten to take that into account.
407 * In the meantime, we'll warn the user if malloc gets it wrong.
409 if ((dmat->common.maxsize <= PAGE_SIZE) &&
410 (dmat->common.alignment < dmat->common.maxsize) &&
411 dmat->common.lowaddr >= ptoa((vm_paddr_t)Maxmem) &&
412 attr == VM_MEMATTR_DEFAULT) {
413 *vaddr = malloc(dmat->common.maxsize, M_DEVBUF, mflags);
414 } else if (dmat->common.nsegments >= btoc(dmat->common.maxsize) &&
415 dmat->common.alignment <= PAGE_SIZE &&
416 (dmat->common.boundary == 0 ||
417 dmat->common.boundary >= dmat->common.lowaddr)) {
418 /* Page-based multi-segment allocations allowed */
419 *vaddr = (void *)kmem_alloc_attr(kernel_arena,
420 dmat->common.maxsize, mflags, 0ul, dmat->common.lowaddr,
422 dmat->bounce_flags |= BUS_DMA_KMEM_ALLOC;
424 *vaddr = (void *)kmem_alloc_contig(kernel_arena,
425 dmat->common.maxsize, mflags, 0ul, dmat->common.lowaddr,
426 dmat->common.alignment != 0 ? dmat->common.alignment : 1ul,
427 dmat->common.boundary, attr);
428 dmat->bounce_flags |= BUS_DMA_KMEM_ALLOC;
430 if (*vaddr == NULL) {
431 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
432 __func__, dmat, dmat->common.flags, ENOMEM);
434 } else if (vtophys(*vaddr) & (dmat->common.alignment - 1)) {
435 printf("bus_dmamem_alloc failed to align memory properly.\n");
437 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
438 __func__, dmat, dmat->common.flags, 0);
443 * Free a piece of memory and it's allociated dmamap, that was allocated
444 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
447 bounce_bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
450 * dmamem does not need to be bounced, so the map should be
451 * NULL and the BUS_DMA_KMEM_ALLOC flag cleared if malloc()
452 * was used and set if kmem_alloc_contig() was used.
455 panic("bus_dmamem_free: Invalid map freed\n");
456 if ((dmat->bounce_flags & BUS_DMA_KMEM_ALLOC) == 0)
457 free(vaddr, M_DEVBUF);
459 kmem_free(kernel_arena, (vm_offset_t)vaddr,
460 dmat->common.maxsize);
461 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat,
466 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf,
467 bus_size_t buflen, int flags)
472 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) {
474 * Count the number of bounce pages
475 * needed in order to complete this transfer
478 while (buflen != 0) {
479 sgsize = MIN(buflen, dmat->common.maxsegsz);
480 if (bus_dma_run_filter(&dmat->common, curaddr)) {
481 sgsize = MIN(sgsize, PAGE_SIZE);
487 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
492 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap,
493 void *buf, bus_size_t buflen, int flags)
496 vm_offset_t vendaddr;
500 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) {
501 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
502 "alignment= %d", dmat->common.lowaddr,
503 ptoa((vm_paddr_t)Maxmem),
504 dmat->common.boundary, dmat->common.alignment);
505 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d",
506 map, &nobounce_dmamap, map->pagesneeded);
508 * Count the number of bounce pages
509 * needed in order to complete this transfer
511 vaddr = (vm_offset_t)buf;
512 vendaddr = (vm_offset_t)buf + buflen;
514 while (vaddr < vendaddr) {
515 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK);
516 if (pmap == kernel_pmap)
517 paddr = pmap_kextract(vaddr);
519 paddr = pmap_extract(pmap, vaddr);
520 if (bus_dma_run_filter(&dmat->common, paddr) != 0) {
521 sg_len = roundup2(sg_len,
522 dmat->common.alignment);
527 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
532 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags)
535 /* Reserve Necessary Bounce Pages */
536 mtx_lock(&bounce_lock);
537 if (flags & BUS_DMA_NOWAIT) {
538 if (reserve_bounce_pages(dmat, map, 0) != 0) {
539 mtx_unlock(&bounce_lock);
543 if (reserve_bounce_pages(dmat, map, 1) != 0) {
544 /* Queue us for resources */
545 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, map, links);
546 mtx_unlock(&bounce_lock);
547 return (EINPROGRESS);
550 mtx_unlock(&bounce_lock);
556 * Add a single contiguous physical range to the segment list.
559 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, bus_addr_t curaddr,
560 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp)
562 bus_addr_t baddr, bmask;
566 * Make sure we don't cross any boundaries.
568 bmask = ~(dmat->common.boundary - 1);
569 if (dmat->common.boundary > 0) {
570 baddr = (curaddr + dmat->common.boundary) & bmask;
571 if (sgsize > (baddr - curaddr))
572 sgsize = (baddr - curaddr);
576 * Insert chunk into a segment, coalescing with
577 * previous segment if possible.
582 segs[seg].ds_addr = curaddr;
583 segs[seg].ds_len = sgsize;
585 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len &&
586 (segs[seg].ds_len + sgsize) <= dmat->common.maxsegsz &&
587 (dmat->common.boundary == 0 ||
588 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
589 segs[seg].ds_len += sgsize;
591 if (++seg >= dmat->common.nsegments)
593 segs[seg].ds_addr = curaddr;
594 segs[seg].ds_len = sgsize;
602 * Utility function to load a physical buffer. segp contains
603 * the starting segment on entrace, and the ending segment on exit.
606 bounce_bus_dmamap_load_phys(bus_dma_tag_t dmat, bus_dmamap_t map,
607 vm_paddr_t buf, bus_size_t buflen, int flags, bus_dma_segment_t *segs,
615 map = &nobounce_dmamap;
618 segs = dmat->segments;
620 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) {
621 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags);
622 if (map->pagesneeded != 0) {
623 error = _bus_dmamap_reserve_pages(dmat, map, flags);
631 sgsize = MIN(buflen, dmat->common.maxsegsz);
632 if (((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) &&
633 map->pagesneeded != 0 &&
634 bus_dma_run_filter(&dmat->common, curaddr)) {
635 sgsize = MIN(sgsize, PAGE_SIZE);
636 curaddr = add_bounce_page(dmat, map, 0, curaddr,
639 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
650 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
654 * Utility function to load a linear buffer. segp contains
655 * the starting segment on entrace, and the ending segment on exit.
658 bounce_bus_dmamap_load_buffer(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
659 bus_size_t buflen, pmap_t pmap, int flags, bus_dma_segment_t *segs,
662 bus_size_t sgsize, max_sgsize;
668 map = &nobounce_dmamap;
671 segs = dmat->segments;
673 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) {
674 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags);
675 if (map->pagesneeded != 0) {
676 error = _bus_dmamap_reserve_pages(dmat, map, flags);
682 vaddr = (vm_offset_t)buf;
685 * Get the physical address for this segment.
687 if (pmap == kernel_pmap)
688 curaddr = pmap_kextract(vaddr);
690 curaddr = pmap_extract(pmap, vaddr);
693 * Compute the segment size, and adjust counts.
695 max_sgsize = MIN(buflen, dmat->common.maxsegsz);
696 sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK);
697 if (((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) &&
698 map->pagesneeded != 0 &&
699 bus_dma_run_filter(&dmat->common, curaddr)) {
700 sgsize = roundup2(sgsize, dmat->common.alignment);
701 sgsize = MIN(sgsize, max_sgsize);
702 curaddr = add_bounce_page(dmat, map, vaddr, curaddr,
705 sgsize = MIN(sgsize, max_sgsize);
707 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
718 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
722 bounce_bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map,
723 struct memdesc *mem, bus_dmamap_callback_t *callback, void *callback_arg)
730 map->callback = callback;
731 map->callback_arg = callback_arg;
734 static bus_dma_segment_t *
735 bounce_bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map,
736 bus_dma_segment_t *segs, int nsegs, int error)
740 segs = dmat->segments;
745 * Release the mapping held by map.
748 bounce_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
750 struct bounce_page *bpage;
752 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
753 STAILQ_REMOVE_HEAD(&map->bpages, links);
754 free_bounce_page(dmat, bpage);
759 bounce_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map,
762 struct bounce_page *bpage;
766 * This bus_dma implementation requires IO-Coherent architecutre.
767 * If IO-Coherency is not guaranteed, cache operations have to be
768 * added to this function.
771 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
773 * Handle data bouncing. We might also
774 * want to add support for invalidating
775 * the caches on broken hardware
777 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
778 "performing bounce", __func__, dmat,
779 dmat->common.flags, op);
781 if ((op & BUS_DMASYNC_PREWRITE) != 0) {
782 while (bpage != NULL) {
783 if (bpage->datavaddr != 0) {
784 bcopy((void *)bpage->datavaddr,
785 (void *)bpage->vaddr,
788 physcopyout(bpage->dataaddr,
789 (void *)bpage->vaddr,
792 bpage = STAILQ_NEXT(bpage, links);
794 dmat->bounce_zone->total_bounced++;
797 if ((op & BUS_DMASYNC_POSTREAD) != 0) {
798 while (bpage != NULL) {
799 if (bpage->datavaddr != 0) {
800 bcopy((void *)bpage->vaddr,
801 (void *)bpage->datavaddr,
804 physcopyin((void *)bpage->vaddr,
808 bpage = STAILQ_NEXT(bpage, links);
810 dmat->bounce_zone->total_bounced++;
816 init_bounce_pages(void *dummy __unused)
820 STAILQ_INIT(&bounce_zone_list);
821 STAILQ_INIT(&bounce_map_waitinglist);
822 STAILQ_INIT(&bounce_map_callbacklist);
823 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
825 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
827 static struct sysctl_ctx_list *
828 busdma_sysctl_tree(struct bounce_zone *bz)
830 return (&bz->sysctl_tree);
833 static struct sysctl_oid *
834 busdma_sysctl_tree_top(struct bounce_zone *bz)
836 return (bz->sysctl_tree_top);
840 alloc_bounce_zone(bus_dma_tag_t dmat)
842 struct bounce_zone *bz;
844 /* Check to see if we already have a suitable zone */
845 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
846 if ((dmat->common.alignment <= bz->alignment) &&
847 (dmat->common.lowaddr >= bz->lowaddr)) {
848 dmat->bounce_zone = bz;
853 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
854 M_NOWAIT | M_ZERO)) == NULL)
857 STAILQ_INIT(&bz->bounce_page_list);
859 bz->reserved_bpages = 0;
860 bz->active_bpages = 0;
861 bz->lowaddr = dmat->common.lowaddr;
862 bz->alignment = MAX(dmat->common.alignment, PAGE_SIZE);
864 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
866 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
867 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
868 dmat->bounce_zone = bz;
870 sysctl_ctx_init(&bz->sysctl_tree);
871 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
872 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
874 if (bz->sysctl_tree_top == NULL) {
875 sysctl_ctx_free(&bz->sysctl_tree);
876 return (0); /* XXX error code? */
879 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
880 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
881 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
882 "Total bounce pages");
883 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
884 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
885 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
886 "Free bounce pages");
887 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
888 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
889 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
890 "Reserved bounce pages");
891 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
892 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
893 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
894 "Active bounce pages");
895 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
896 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
897 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
898 "Total bounce requests");
899 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
900 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
901 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
902 "Total bounce requests that were deferred");
903 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
904 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
905 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
906 SYSCTL_ADD_UAUTO(busdma_sysctl_tree(bz),
907 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
908 "alignment", CTLFLAG_RD, &bz->alignment, "");
914 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
916 struct bounce_zone *bz;
919 bz = dmat->bounce_zone;
921 while (numpages > 0) {
922 struct bounce_page *bpage;
924 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
929 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
930 M_NOWAIT, 0ul, bz->lowaddr, PAGE_SIZE, 0);
931 if (bpage->vaddr == 0) {
932 free(bpage, M_DEVBUF);
935 bpage->busaddr = pmap_kextract(bpage->vaddr);
936 mtx_lock(&bounce_lock);
937 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
941 mtx_unlock(&bounce_lock);
949 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
951 struct bounce_zone *bz;
954 mtx_assert(&bounce_lock, MA_OWNED);
955 bz = dmat->bounce_zone;
956 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
957 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
958 return (map->pagesneeded - (map->pagesreserved + pages));
959 bz->free_bpages -= pages;
960 bz->reserved_bpages += pages;
961 map->pagesreserved += pages;
962 pages = map->pagesneeded - map->pagesreserved;
968 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
969 bus_addr_t addr, bus_size_t size)
971 struct bounce_zone *bz;
972 struct bounce_page *bpage;
974 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
975 KASSERT(map != NULL && map != &nobounce_dmamap,
976 ("add_bounce_page: bad map %p", map));
978 bz = dmat->bounce_zone;
979 if (map->pagesneeded == 0)
980 panic("add_bounce_page: map doesn't need any pages");
983 if (map->pagesreserved == 0)
984 panic("add_bounce_page: map doesn't need any pages");
985 map->pagesreserved--;
987 mtx_lock(&bounce_lock);
988 bpage = STAILQ_FIRST(&bz->bounce_page_list);
990 panic("add_bounce_page: free page list is empty");
992 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
993 bz->reserved_bpages--;
995 mtx_unlock(&bounce_lock);
997 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) {
998 /* Page offset needs to be preserved. */
999 bpage->vaddr |= addr & PAGE_MASK;
1000 bpage->busaddr |= addr & PAGE_MASK;
1002 bpage->datavaddr = vaddr;
1003 bpage->dataaddr = addr;
1004 bpage->datacount = size;
1005 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1006 return (bpage->busaddr);
1010 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1012 struct bus_dmamap *map;
1013 struct bounce_zone *bz;
1015 bz = dmat->bounce_zone;
1016 bpage->datavaddr = 0;
1017 bpage->datacount = 0;
1018 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) {
1020 * Reset the bounce page to start at offset 0. Other uses
1021 * of this bounce page may need to store a full page of
1022 * data and/or assume it starts on a page boundary.
1024 bpage->vaddr &= ~PAGE_MASK;
1025 bpage->busaddr &= ~PAGE_MASK;
1028 mtx_lock(&bounce_lock);
1029 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1031 bz->active_bpages--;
1032 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1033 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1034 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1035 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1037 busdma_swi_pending = 1;
1038 bz->total_deferred++;
1039 swi_sched(vm_ih, 0);
1042 mtx_unlock(&bounce_lock);
1049 struct bus_dmamap *map;
1051 mtx_lock(&bounce_lock);
1052 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1053 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1054 mtx_unlock(&bounce_lock);
1056 (dmat->common.lockfunc)(dmat->common.lockfuncarg, BUS_DMA_LOCK);
1057 bus_dmamap_load_mem(map->dmat, map, &map->mem,
1058 map->callback, map->callback_arg, BUS_DMA_WAITOK);
1059 (dmat->common.lockfunc)(dmat->common.lockfuncarg,
1061 mtx_lock(&bounce_lock);
1063 mtx_unlock(&bounce_lock);
1066 struct bus_dma_impl bus_dma_bounce_impl = {
1067 .tag_create = bounce_bus_dma_tag_create,
1068 .tag_destroy = bounce_bus_dma_tag_destroy,
1069 .map_create = bounce_bus_dmamap_create,
1070 .map_destroy = bounce_bus_dmamap_destroy,
1071 .mem_alloc = bounce_bus_dmamem_alloc,
1072 .mem_free = bounce_bus_dmamem_free,
1073 .load_phys = bounce_bus_dmamap_load_phys,
1074 .load_buffer = bounce_bus_dmamap_load_buffer,
1075 .load_ma = bus_dmamap_load_ma_triv,
1076 .map_waitok = bounce_bus_dmamap_waitok,
1077 .map_complete = bounce_bus_dmamap_complete,
1078 .map_unload = bounce_bus_dmamap_unload,
1079 .map_sync = bounce_bus_dmamap_sync