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>
31 #include <sys/systm.h>
32 #include <sys/malloc.h>
34 #include <sys/interrupt.h>
35 #include <sys/kernel.h>
39 #include <sys/memdesc.h>
40 #include <sys/mutex.h>
41 #include <sys/sysctl.h>
45 #include <vm/vm_extern.h>
46 #include <vm/vm_kern.h>
47 #include <vm/vm_page.h>
48 #include <vm/vm_map.h>
50 #include <machine/atomic.h>
51 #include <machine/bus.h>
52 #include <machine/md_var.h>
53 #include <machine/specialreg.h>
54 #include <x86/include/busdma_impl.h>
57 #define MAX_BPAGES 512
59 #define MAX_BPAGES 8192
63 BUS_DMA_COULD_BOUNCE = 0x01,
64 BUS_DMA_MIN_ALLOC_COMP = 0x02,
65 BUS_DMA_KMEM_ALLOC = 0x04,
71 struct bus_dma_tag_common common;
74 bus_dma_segment_t *segments;
75 struct bounce_zone *bounce_zone;
79 vm_offset_t vaddr; /* kva of bounce buffer */
80 bus_addr_t busaddr; /* Physical address */
81 vm_offset_t datavaddr; /* kva of client data */
82 bus_addr_t dataaddr; /* client physical address */
83 bus_size_t datacount; /* client data count */
84 STAILQ_ENTRY(bounce_page) links;
87 int busdma_swi_pending;
90 STAILQ_ENTRY(bounce_zone) links;
91 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
103 struct sysctl_ctx_list sysctl_tree;
104 struct sysctl_oid *sysctl_tree_top;
107 static struct mtx bounce_lock;
108 static int total_bpages;
109 static int busdma_zonecount;
110 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
112 static SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
113 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
114 "Total bounce pages");
117 struct bp_list bpages;
122 bus_dmamap_callback_t *callback;
124 STAILQ_ENTRY(bus_dmamap) links;
127 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
128 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
129 static struct bus_dmamap nobounce_dmamap;
131 static void init_bounce_pages(void *dummy);
132 static int alloc_bounce_zone(bus_dma_tag_t dmat);
133 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
134 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
136 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
137 vm_offset_t vaddr, bus_addr_t addr,
139 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
140 int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
141 static void _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
142 pmap_t pmap, void *buf, bus_size_t buflen,
144 static void _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map,
145 vm_paddr_t buf, bus_size_t buflen,
147 static int _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
151 * Allocate a device specific dma_tag.
154 bounce_bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
155 bus_addr_t boundary, bus_addr_t lowaddr, bus_addr_t highaddr,
156 bus_dma_filter_t *filter, void *filterarg, bus_size_t maxsize,
157 int nsegments, bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
158 void *lockfuncarg, bus_dma_tag_t *dmat)
160 bus_dma_tag_t newtag;
164 error = common_bus_dma_tag_create(parent != NULL ? &parent->common :
165 NULL, alignment, boundary, lowaddr, highaddr, filter, filterarg,
166 maxsize, nsegments, maxsegsz, flags, lockfunc, lockfuncarg,
167 sizeof (struct bus_dma_tag), (void **)&newtag);
171 newtag->common.impl = &bus_dma_bounce_impl;
172 newtag->map_count = 0;
173 newtag->segments = NULL;
175 if (parent != NULL && ((newtag->common.filter != NULL) ||
176 ((parent->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0)))
177 newtag->bounce_flags |= BUS_DMA_COULD_BOUNCE;
179 if (newtag->common.lowaddr < ptoa((vm_paddr_t)Maxmem) ||
180 newtag->common.alignment > 1)
181 newtag->bounce_flags |= BUS_DMA_COULD_BOUNCE;
183 if (((newtag->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) &&
184 (flags & BUS_DMA_ALLOCNOW) != 0) {
185 struct bounce_zone *bz;
188 if ((error = alloc_bounce_zone(newtag)) != 0) {
189 free(newtag, M_DEVBUF);
192 bz = newtag->bounce_zone;
194 if (ptoa(bz->total_bpages) < maxsize) {
197 pages = atop(maxsize) - bz->total_bpages;
199 /* Add pages to our bounce pool */
200 if (alloc_bounce_pages(newtag, pages) < pages)
203 /* Performed initial allocation */
204 newtag->bounce_flags |= BUS_DMA_MIN_ALLOC_COMP;
209 free(newtag, M_DEVBUF);
212 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
213 __func__, newtag, (newtag != NULL ? newtag->common.flags : 0),
219 bounce_bus_dma_tag_destroy(bus_dma_tag_t dmat)
221 bus_dma_tag_t dmat_copy, parent;
228 if (dmat->map_count != 0) {
232 while (dmat != NULL) {
233 parent = (bus_dma_tag_t)dmat->common.parent;
234 atomic_subtract_int(&dmat->common.ref_count, 1);
235 if (dmat->common.ref_count == 0) {
236 if (dmat->segments != NULL)
237 free(dmat->segments, M_DEVBUF);
238 free(dmat, M_DEVBUF);
240 * Last reference count, so
241 * release our reference
242 * count on our parent.
250 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
255 * Allocate a handle for mapping from kva/uva/physical
256 * address space into bus device space.
259 bounce_bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
261 struct bounce_zone *bz;
262 int error, maxpages, pages;
266 if (dmat->segments == NULL) {
267 dmat->segments = (bus_dma_segment_t *)malloc(
268 sizeof(bus_dma_segment_t) * dmat->common.nsegments,
270 if (dmat->segments == NULL) {
271 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
272 __func__, dmat, ENOMEM);
278 * Bouncing might be required if the driver asks for an active
279 * exclusion region, a data alignment that is stricter than 1, and/or
280 * an active address boundary.
282 if (dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) {
284 if (dmat->bounce_zone == NULL) {
285 if ((error = alloc_bounce_zone(dmat)) != 0)
288 bz = dmat->bounce_zone;
290 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
293 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
294 __func__, dmat, ENOMEM);
298 /* Initialize the new map */
299 STAILQ_INIT(&((*mapp)->bpages));
302 * Attempt to add pages to our pool on a per-instance
303 * basis up to a sane limit.
305 if (dmat->common.alignment > 1)
306 maxpages = MAX_BPAGES;
308 maxpages = MIN(MAX_BPAGES, Maxmem -
309 atop(dmat->common.lowaddr));
310 if ((dmat->bounce_flags & BUS_DMA_MIN_ALLOC_COMP) == 0 ||
311 (bz->map_count > 0 && bz->total_bpages < maxpages)) {
312 pages = MAX(atop(dmat->common.maxsize), 1);
313 pages = MIN(maxpages - bz->total_bpages, pages);
314 pages = MAX(pages, 1);
315 if (alloc_bounce_pages(dmat, pages) < pages)
317 if ((dmat->bounce_flags & BUS_DMA_MIN_ALLOC_COMP)
320 dmat->bounce_flags |=
321 BUS_DMA_MIN_ALLOC_COMP;
332 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
333 __func__, dmat, dmat->common.flags, error);
338 * Destroy a handle for mapping from kva/uva/physical
339 * address space into bus device space.
342 bounce_bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
345 if (map != NULL && map != &nobounce_dmamap) {
346 if (STAILQ_FIRST(&map->bpages) != NULL) {
347 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
348 __func__, dmat, EBUSY);
351 if (dmat->bounce_zone)
352 dmat->bounce_zone->map_count--;
356 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
362 * Allocate a piece of memory that can be efficiently mapped into
363 * bus device space based on the constraints lited in the dma tag.
364 * A dmamap to for use with dmamap_load is also allocated.
367 bounce_bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
373 if (flags & BUS_DMA_NOWAIT)
378 /* If we succeed, no mapping/bouncing will be required */
381 if (dmat->segments == NULL) {
382 dmat->segments = (bus_dma_segment_t *)malloc(
383 sizeof(bus_dma_segment_t) * dmat->common.nsegments,
385 if (dmat->segments == NULL) {
386 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
387 __func__, dmat, dmat->common.flags, ENOMEM);
391 if (flags & BUS_DMA_ZERO)
393 if (flags & BUS_DMA_NOCACHE)
394 attr = VM_MEMATTR_UNCACHEABLE;
396 attr = VM_MEMATTR_DEFAULT;
400 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact
401 * alignment guarantees of malloc need to be nailed down, and the
402 * code below should be rewritten to take that into account.
404 * In the meantime, we'll warn the user if malloc gets it wrong.
406 if ((dmat->common.maxsize <= PAGE_SIZE) &&
407 (dmat->common.alignment < dmat->common.maxsize) &&
408 dmat->common.lowaddr >= ptoa((vm_paddr_t)Maxmem) &&
409 attr == VM_MEMATTR_DEFAULT) {
410 *vaddr = malloc(dmat->common.maxsize, M_DEVBUF, mflags);
411 } else if (dmat->common.nsegments >= btoc(dmat->common.maxsize) &&
412 dmat->common.alignment <= PAGE_SIZE &&
413 (dmat->common.boundary == 0 ||
414 dmat->common.boundary >= dmat->common.lowaddr)) {
415 /* Page-based multi-segment allocations allowed */
416 *vaddr = (void *)kmem_alloc_attr(kernel_arena,
417 dmat->common.maxsize, mflags, 0ul, dmat->common.lowaddr,
419 dmat->bounce_flags |= BUS_DMA_KMEM_ALLOC;
421 *vaddr = (void *)kmem_alloc_contig(kernel_arena,
422 dmat->common.maxsize, mflags, 0ul, dmat->common.lowaddr,
423 dmat->common.alignment != 0 ? dmat->common.alignment : 1ul,
424 dmat->common.boundary, attr);
425 dmat->bounce_flags |= BUS_DMA_KMEM_ALLOC;
427 if (*vaddr == NULL) {
428 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
429 __func__, dmat, dmat->common.flags, ENOMEM);
431 } else if (vtophys(*vaddr) & (dmat->common.alignment - 1)) {
432 printf("bus_dmamem_alloc failed to align memory properly.\n");
434 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
435 __func__, dmat, dmat->common.flags, 0);
440 * Free a piece of memory and it's allociated dmamap, that was allocated
441 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
444 bounce_bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
447 * dmamem does not need to be bounced, so the map should be
448 * NULL and the BUS_DMA_KMEM_ALLOC flag cleared if malloc()
449 * was used and set if kmem_alloc_contig() was used.
452 panic("bus_dmamem_free: Invalid map freed\n");
453 if ((dmat->bounce_flags & BUS_DMA_KMEM_ALLOC) == 0)
454 free(vaddr, M_DEVBUF);
456 kmem_free(kernel_arena, (vm_offset_t)vaddr,
457 dmat->common.maxsize);
458 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat,
463 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf,
464 bus_size_t buflen, int flags)
469 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) {
471 * Count the number of bounce pages
472 * needed in order to complete this transfer
475 while (buflen != 0) {
476 sgsize = MIN(buflen, dmat->common.maxsegsz);
477 if (bus_dma_run_filter(&dmat->common, curaddr)) {
478 sgsize = MIN(sgsize, PAGE_SIZE);
484 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
489 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap,
490 void *buf, bus_size_t buflen, int flags)
493 vm_offset_t vendaddr;
497 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) {
498 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
499 "alignment= %d", dmat->common.lowaddr,
500 ptoa((vm_paddr_t)Maxmem),
501 dmat->common.boundary, dmat->common.alignment);
502 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d",
503 map, &nobounce_dmamap, map->pagesneeded);
505 * Count the number of bounce pages
506 * needed in order to complete this transfer
508 vaddr = (vm_offset_t)buf;
509 vendaddr = (vm_offset_t)buf + buflen;
511 while (vaddr < vendaddr) {
512 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK);
513 if (pmap == kernel_pmap)
514 paddr = pmap_kextract(vaddr);
516 paddr = pmap_extract(pmap, vaddr);
517 if (bus_dma_run_filter(&dmat->common, paddr) != 0) {
518 sg_len = roundup2(sg_len,
519 dmat->common.alignment);
524 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
529 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags)
532 /* Reserve Necessary Bounce Pages */
533 mtx_lock(&bounce_lock);
534 if (flags & BUS_DMA_NOWAIT) {
535 if (reserve_bounce_pages(dmat, map, 0) != 0) {
536 mtx_unlock(&bounce_lock);
540 if (reserve_bounce_pages(dmat, map, 1) != 0) {
541 /* Queue us for resources */
542 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, map, links);
543 mtx_unlock(&bounce_lock);
544 return (EINPROGRESS);
547 mtx_unlock(&bounce_lock);
553 * Add a single contiguous physical range to the segment list.
556 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, bus_addr_t curaddr,
557 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp)
559 bus_addr_t baddr, bmask;
563 * Make sure we don't cross any boundaries.
565 bmask = ~(dmat->common.boundary - 1);
566 if (dmat->common.boundary > 0) {
567 baddr = (curaddr + dmat->common.boundary) & bmask;
568 if (sgsize > (baddr - curaddr))
569 sgsize = (baddr - curaddr);
573 * Insert chunk into a segment, coalescing with
574 * previous segment if possible.
579 segs[seg].ds_addr = curaddr;
580 segs[seg].ds_len = sgsize;
582 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len &&
583 (segs[seg].ds_len + sgsize) <= dmat->common.maxsegsz &&
584 (dmat->common.boundary == 0 ||
585 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
586 segs[seg].ds_len += sgsize;
588 if (++seg >= dmat->common.nsegments)
590 segs[seg].ds_addr = curaddr;
591 segs[seg].ds_len = sgsize;
599 * Utility function to load a physical buffer. segp contains
600 * the starting segment on entrace, and the ending segment on exit.
603 bounce_bus_dmamap_load_phys(bus_dma_tag_t dmat, bus_dmamap_t map,
604 vm_paddr_t buf, bus_size_t buflen, int flags, bus_dma_segment_t *segs,
612 map = &nobounce_dmamap;
615 segs = dmat->segments;
617 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) {
618 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags);
619 if (map->pagesneeded != 0) {
620 error = _bus_dmamap_reserve_pages(dmat, map, flags);
628 sgsize = MIN(buflen, dmat->common.maxsegsz);
629 if (((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) &&
630 map->pagesneeded != 0 &&
631 bus_dma_run_filter(&dmat->common, curaddr)) {
632 sgsize = MIN(sgsize, PAGE_SIZE);
633 curaddr = add_bounce_page(dmat, map, 0, curaddr,
636 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
647 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
651 * Utility function to load a linear buffer. segp contains
652 * the starting segment on entrace, and the ending segment on exit.
655 bounce_bus_dmamap_load_buffer(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
656 bus_size_t buflen, pmap_t pmap, int flags, bus_dma_segment_t *segs,
659 bus_size_t sgsize, max_sgsize;
665 map = &nobounce_dmamap;
668 segs = dmat->segments;
670 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) {
671 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags);
672 if (map->pagesneeded != 0) {
673 error = _bus_dmamap_reserve_pages(dmat, map, flags);
679 vaddr = (vm_offset_t)buf;
682 * Get the physical address for this segment.
684 if (pmap == kernel_pmap)
685 curaddr = pmap_kextract(vaddr);
687 curaddr = pmap_extract(pmap, vaddr);
690 * Compute the segment size, and adjust counts.
692 max_sgsize = MIN(buflen, dmat->common.maxsegsz);
693 sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK);
694 if (((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) &&
695 map->pagesneeded != 0 &&
696 bus_dma_run_filter(&dmat->common, curaddr)) {
697 sgsize = roundup2(sgsize, dmat->common.alignment);
698 sgsize = MIN(sgsize, max_sgsize);
699 curaddr = add_bounce_page(dmat, map, vaddr, curaddr,
702 sgsize = MIN(sgsize, max_sgsize);
704 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
715 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
719 bounce_bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map,
720 struct memdesc *mem, bus_dmamap_callback_t *callback, void *callback_arg)
727 map->callback = callback;
728 map->callback_arg = callback_arg;
731 static bus_dma_segment_t *
732 bounce_bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map,
733 bus_dma_segment_t *segs, int nsegs, int error)
737 segs = dmat->segments;
742 * Release the mapping held by map.
745 bounce_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
747 struct bounce_page *bpage;
749 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
750 STAILQ_REMOVE_HEAD(&map->bpages, links);
751 free_bounce_page(dmat, bpage);
756 bounce_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map,
759 struct bounce_page *bpage;
761 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
763 * Handle data bouncing. We might also
764 * want to add support for invalidating
765 * the caches on broken hardware
767 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
768 "performing bounce", __func__, dmat,
769 dmat->common.flags, op);
771 if ((op & BUS_DMASYNC_PREWRITE) != 0) {
772 while (bpage != NULL) {
773 if (bpage->datavaddr != 0) {
774 bcopy((void *)bpage->datavaddr,
775 (void *)bpage->vaddr,
778 physcopyout(bpage->dataaddr,
779 (void *)bpage->vaddr,
782 bpage = STAILQ_NEXT(bpage, links);
784 dmat->bounce_zone->total_bounced++;
787 if ((op & BUS_DMASYNC_POSTREAD) != 0) {
788 while (bpage != NULL) {
789 if (bpage->datavaddr != 0) {
790 bcopy((void *)bpage->vaddr,
791 (void *)bpage->datavaddr,
794 physcopyin((void *)bpage->vaddr,
798 bpage = STAILQ_NEXT(bpage, links);
800 dmat->bounce_zone->total_bounced++;
806 init_bounce_pages(void *dummy __unused)
810 STAILQ_INIT(&bounce_zone_list);
811 STAILQ_INIT(&bounce_map_waitinglist);
812 STAILQ_INIT(&bounce_map_callbacklist);
813 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
815 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
817 static struct sysctl_ctx_list *
818 busdma_sysctl_tree(struct bounce_zone *bz)
820 return (&bz->sysctl_tree);
823 static struct sysctl_oid *
824 busdma_sysctl_tree_top(struct bounce_zone *bz)
826 return (bz->sysctl_tree_top);
830 alloc_bounce_zone(bus_dma_tag_t dmat)
832 struct bounce_zone *bz;
834 /* Check to see if we already have a suitable zone */
835 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
836 if ((dmat->common.alignment <= bz->alignment) &&
837 (dmat->common.lowaddr >= bz->lowaddr)) {
838 dmat->bounce_zone = bz;
843 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
844 M_NOWAIT | M_ZERO)) == NULL)
847 STAILQ_INIT(&bz->bounce_page_list);
849 bz->reserved_bpages = 0;
850 bz->active_bpages = 0;
851 bz->lowaddr = dmat->common.lowaddr;
852 bz->alignment = MAX(dmat->common.alignment, PAGE_SIZE);
854 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
856 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
857 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
858 dmat->bounce_zone = bz;
860 sysctl_ctx_init(&bz->sysctl_tree);
861 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
862 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
864 if (bz->sysctl_tree_top == NULL) {
865 sysctl_ctx_free(&bz->sysctl_tree);
866 return (0); /* XXX error code? */
869 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
870 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
871 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
872 "Total bounce pages");
873 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
874 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
875 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
876 "Free bounce pages");
877 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
878 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
879 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
880 "Reserved bounce pages");
881 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
882 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
883 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
884 "Active bounce pages");
885 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
886 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
887 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
888 "Total bounce requests");
889 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
890 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
891 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
892 "Total bounce requests that were deferred");
893 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
894 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
895 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
896 SYSCTL_ADD_UAUTO(busdma_sysctl_tree(bz),
897 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
898 "alignment", CTLFLAG_RD, &bz->alignment, "");
904 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
906 struct bounce_zone *bz;
909 bz = dmat->bounce_zone;
911 while (numpages > 0) {
912 struct bounce_page *bpage;
914 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
919 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
924 if (bpage->vaddr == 0) {
925 free(bpage, M_DEVBUF);
928 bpage->busaddr = pmap_kextract(bpage->vaddr);
929 mtx_lock(&bounce_lock);
930 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
934 mtx_unlock(&bounce_lock);
942 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
944 struct bounce_zone *bz;
947 mtx_assert(&bounce_lock, MA_OWNED);
948 bz = dmat->bounce_zone;
949 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
950 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
951 return (map->pagesneeded - (map->pagesreserved + pages));
952 bz->free_bpages -= pages;
953 bz->reserved_bpages += pages;
954 map->pagesreserved += pages;
955 pages = map->pagesneeded - map->pagesreserved;
961 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
962 bus_addr_t addr, bus_size_t size)
964 struct bounce_zone *bz;
965 struct bounce_page *bpage;
967 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
968 KASSERT(map != NULL && map != &nobounce_dmamap,
969 ("add_bounce_page: bad map %p", map));
971 bz = dmat->bounce_zone;
972 if (map->pagesneeded == 0)
973 panic("add_bounce_page: map doesn't need any pages");
976 if (map->pagesreserved == 0)
977 panic("add_bounce_page: map doesn't need any pages");
978 map->pagesreserved--;
980 mtx_lock(&bounce_lock);
981 bpage = STAILQ_FIRST(&bz->bounce_page_list);
983 panic("add_bounce_page: free page list is empty");
985 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
986 bz->reserved_bpages--;
988 mtx_unlock(&bounce_lock);
990 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) {
991 /* Page offset needs to be preserved. */
992 bpage->vaddr |= addr & PAGE_MASK;
993 bpage->busaddr |= addr & PAGE_MASK;
995 bpage->datavaddr = vaddr;
996 bpage->dataaddr = addr;
997 bpage->datacount = size;
998 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
999 return (bpage->busaddr);
1003 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1005 struct bus_dmamap *map;
1006 struct bounce_zone *bz;
1008 bz = dmat->bounce_zone;
1009 bpage->datavaddr = 0;
1010 bpage->datacount = 0;
1011 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) {
1013 * Reset the bounce page to start at offset 0. Other uses
1014 * of this bounce page may need to store a full page of
1015 * data and/or assume it starts on a page boundary.
1017 bpage->vaddr &= ~PAGE_MASK;
1018 bpage->busaddr &= ~PAGE_MASK;
1021 mtx_lock(&bounce_lock);
1022 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1024 bz->active_bpages--;
1025 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1026 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1027 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1028 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1030 busdma_swi_pending = 1;
1031 bz->total_deferred++;
1032 swi_sched(vm_ih, 0);
1035 mtx_unlock(&bounce_lock);
1042 struct bus_dmamap *map;
1044 mtx_lock(&bounce_lock);
1045 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1046 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1047 mtx_unlock(&bounce_lock);
1049 (dmat->common.lockfunc)(dmat->common.lockfuncarg, BUS_DMA_LOCK);
1050 bus_dmamap_load_mem(map->dmat, map, &map->mem,
1051 map->callback, map->callback_arg, BUS_DMA_WAITOK);
1052 (dmat->common.lockfunc)(dmat->common.lockfuncarg,
1054 mtx_lock(&bounce_lock);
1056 mtx_unlock(&bounce_lock);
1059 struct bus_dma_impl bus_dma_bounce_impl = {
1060 .tag_create = bounce_bus_dma_tag_create,
1061 .tag_destroy = bounce_bus_dma_tag_destroy,
1062 .map_create = bounce_bus_dmamap_create,
1063 .map_destroy = bounce_bus_dmamap_destroy,
1064 .mem_alloc = bounce_bus_dmamem_alloc,
1065 .mem_free = bounce_bus_dmamem_free,
1066 .load_phys = bounce_bus_dmamap_load_phys,
1067 .load_buffer = bounce_bus_dmamap_load_buffer,
1068 .load_ma = bus_dmamap_load_ma_triv,
1069 .map_waitok = bounce_bus_dmamap_waitok,
1070 .map_complete = bounce_bus_dmamap_complete,
1071 .map_unload = bounce_bus_dmamap_unload,
1072 .map_sync = bounce_bus_dmamap_sync