2 * Copyright (c) 1997, 1998 Justin T. Gibbs.
3 * Copyright (c) 2015-2016 The FreeBSD Foundation
6 * Portions of this software were developed by Andrew Turner
7 * under sponsorship of the FreeBSD Foundation.
9 * Portions of this software were developed by Semihalf
10 * under sponsorship of the FreeBSD Foundation.
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions, and the following disclaimer,
17 * without modification, immediately at the beginning of the file.
18 * 2. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
25 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/malloc.h>
41 #include <sys/interrupt.h>
42 #include <sys/kernel.h>
46 #include <sys/memdesc.h>
47 #include <sys/mutex.h>
48 #include <sys/sysctl.h>
52 #include <vm/vm_extern.h>
53 #include <vm/vm_kern.h>
54 #include <vm/vm_page.h>
55 #include <vm/vm_map.h>
57 #include <machine/atomic.h>
58 #include <machine/bus.h>
59 #include <machine/md_var.h>
60 #include <arm64/include/bus_dma_impl.h>
62 #define MAX_BPAGES 4096
65 BF_COULD_BOUNCE = 0x01,
66 BF_MIN_ALLOC_COMP = 0x02,
74 struct bus_dma_tag_common common;
77 bus_dma_segment_t *segments;
78 struct bounce_zone *bounce_zone;
82 vm_offset_t vaddr; /* kva of bounce buffer */
83 bus_addr_t busaddr; /* Physical address */
84 vm_offset_t datavaddr; /* kva of client data */
85 vm_page_t datapage; /* physical page of client data */
86 vm_offset_t dataoffs; /* page offset of client data */
87 bus_size_t datacount; /* client data count */
88 STAILQ_ENTRY(bounce_page) links;
91 int busdma_swi_pending;
94 STAILQ_ENTRY(bounce_zone) links;
95 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
103 bus_size_t alignment;
107 struct sysctl_ctx_list sysctl_tree;
108 struct sysctl_oid *sysctl_tree_top;
111 static struct mtx bounce_lock;
112 static int total_bpages;
113 static int busdma_zonecount;
114 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
116 static SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
117 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
118 "Total bounce pages");
121 vm_offset_t vaddr; /* kva of client data */
122 bus_addr_t paddr; /* physical address */
123 vm_page_t pages; /* starting page of client data */
124 bus_size_t datacount; /* client data count */
128 struct bp_list bpages;
133 bus_dmamap_callback_t *callback;
135 STAILQ_ENTRY(bus_dmamap) links;
137 #define DMAMAP_COULD_BOUNCE (1 << 0)
138 #define DMAMAP_FROM_DMAMEM (1 << 1)
140 struct sync_list slist[];
143 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
144 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
146 static void init_bounce_pages(void *dummy);
147 static int alloc_bounce_zone(bus_dma_tag_t dmat);
148 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
149 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
151 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
152 vm_offset_t vaddr, bus_addr_t addr, bus_size_t size);
153 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
154 int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
155 static void _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
156 pmap_t pmap, void *buf, bus_size_t buflen, int flags);
157 static void _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map,
158 vm_paddr_t buf, bus_size_t buflen, int flags);
159 static int _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
163 * Allocate a device specific dma_tag.
166 bounce_bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
167 bus_addr_t boundary, bus_addr_t lowaddr, bus_addr_t highaddr,
168 bus_dma_filter_t *filter, void *filterarg, bus_size_t maxsize,
169 int nsegments, bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
170 void *lockfuncarg, bus_dma_tag_t *dmat)
172 bus_dma_tag_t newtag;
176 error = common_bus_dma_tag_create(parent != NULL ? &parent->common :
177 NULL, alignment, boundary, lowaddr, highaddr, filter, filterarg,
178 maxsize, nsegments, maxsegsz, flags, lockfunc, lockfuncarg,
179 sizeof (struct bus_dma_tag), (void **)&newtag);
183 newtag->common.impl = &bus_dma_bounce_impl;
184 newtag->map_count = 0;
185 newtag->segments = NULL;
187 if ((flags & BUS_DMA_COHERENT) != 0)
188 newtag->bounce_flags |= BF_COHERENT;
190 if (parent != NULL) {
191 if ((newtag->common.filter != NULL ||
192 (parent->bounce_flags & BF_COULD_BOUNCE) != 0))
193 newtag->bounce_flags |= BF_COULD_BOUNCE;
195 /* Copy some flags from the parent */
196 newtag->bounce_flags |= parent->bounce_flags & BF_COHERENT;
199 if (newtag->common.lowaddr < ptoa((vm_paddr_t)Maxmem) ||
200 newtag->common.alignment > 1)
201 newtag->bounce_flags |= BF_COULD_BOUNCE;
203 if (((newtag->bounce_flags & BF_COULD_BOUNCE) != 0) &&
204 (flags & BUS_DMA_ALLOCNOW) != 0) {
205 struct bounce_zone *bz;
208 if ((error = alloc_bounce_zone(newtag)) != 0) {
209 free(newtag, M_DEVBUF);
212 bz = newtag->bounce_zone;
214 if (ptoa(bz->total_bpages) < maxsize) {
217 pages = atop(maxsize) - bz->total_bpages;
219 /* Add pages to our bounce pool */
220 if (alloc_bounce_pages(newtag, pages) < pages)
223 /* Performed initial allocation */
224 newtag->bounce_flags |= BF_MIN_ALLOC_COMP;
229 free(newtag, M_DEVBUF);
232 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
233 __func__, newtag, (newtag != NULL ? newtag->common.flags : 0),
239 bounce_bus_dma_tag_destroy(bus_dma_tag_t dmat)
241 bus_dma_tag_t dmat_copy, parent;
248 if (dmat->map_count != 0) {
252 while (dmat != NULL) {
253 parent = (bus_dma_tag_t)dmat->common.parent;
254 atomic_subtract_int(&dmat->common.ref_count, 1);
255 if (dmat->common.ref_count == 0) {
256 if (dmat->segments != NULL)
257 free(dmat->segments, M_DEVBUF);
258 free(dmat, M_DEVBUF);
260 * Last reference count, so
261 * release our reference
262 * count on our parent.
270 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
275 alloc_dmamap(bus_dma_tag_t dmat, int flags)
280 mapsize = sizeof(*map);
281 mapsize += sizeof(struct sync_list) * dmat->common.nsegments;
282 map = malloc(mapsize, M_DEVBUF, flags | M_ZERO);
286 /* Initialize the new map */
287 STAILQ_INIT(&map->bpages);
293 * Allocate a handle for mapping from kva/uva/physical
294 * address space into bus device space.
297 bounce_bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
299 struct bounce_zone *bz;
300 int error, maxpages, pages;
304 if (dmat->segments == NULL) {
305 dmat->segments = (bus_dma_segment_t *)malloc(
306 sizeof(bus_dma_segment_t) * dmat->common.nsegments,
308 if (dmat->segments == NULL) {
309 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
310 __func__, dmat, ENOMEM);
315 *mapp = alloc_dmamap(dmat, M_NOWAIT);
317 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
318 __func__, dmat, ENOMEM);
323 * Bouncing might be required if the driver asks for an active
324 * exclusion region, a data alignment that is stricter than 1, and/or
325 * an active address boundary.
327 if (dmat->bounce_flags & BF_COULD_BOUNCE) {
329 if (dmat->bounce_zone == NULL) {
330 if ((error = alloc_bounce_zone(dmat)) != 0) {
331 free(*mapp, M_DEVBUF);
335 bz = dmat->bounce_zone;
337 (*mapp)->flags = DMAMAP_COULD_BOUNCE;
340 * Attempt to add pages to our pool on a per-instance
341 * basis up to a sane limit.
343 if (dmat->common.alignment > 1)
344 maxpages = MAX_BPAGES;
346 maxpages = MIN(MAX_BPAGES, Maxmem -
347 atop(dmat->common.lowaddr));
348 if ((dmat->bounce_flags & BF_MIN_ALLOC_COMP) == 0 ||
349 (bz->map_count > 0 && bz->total_bpages < maxpages)) {
350 pages = MAX(atop(dmat->common.maxsize), 1);
351 pages = MIN(maxpages - bz->total_bpages, pages);
352 pages = MAX(pages, 1);
353 if (alloc_bounce_pages(dmat, pages) < pages)
355 if ((dmat->bounce_flags & BF_MIN_ALLOC_COMP)
358 dmat->bounce_flags |=
369 free(*mapp, M_DEVBUF);
370 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
371 __func__, dmat, dmat->common.flags, error);
376 * Destroy a handle for mapping from kva/uva/physical
377 * address space into bus device space.
380 bounce_bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
383 /* Check we are destroying the correct map type */
384 if ((map->flags & DMAMAP_FROM_DMAMEM) != 0)
385 panic("bounce_bus_dmamap_destroy: Invalid map freed\n");
387 if (STAILQ_FIRST(&map->bpages) != NULL || map->sync_count != 0) {
388 CTR3(KTR_BUSDMA, "%s: tag %p error %d", __func__, dmat, EBUSY);
391 if (dmat->bounce_zone) {
392 KASSERT((map->flags & DMAMAP_COULD_BOUNCE) != 0,
393 ("%s: Bounce zone when cannot bounce", __func__));
394 dmat->bounce_zone->map_count--;
398 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
404 * Allocate a piece of memory that can be efficiently mapped into
405 * bus device space based on the constraints lited in the dma tag.
406 * A dmamap to for use with dmamap_load is also allocated.
409 bounce_bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
414 * This bus_dma implementation requires IO-Coherent architecutre.
415 * If IO-Coherency is not guaranteed, the BUS_DMA_COHERENT flag has
416 * to be implented using non-cacheable memory.
422 if (flags & BUS_DMA_NOWAIT)
427 if (dmat->segments == NULL) {
428 dmat->segments = (bus_dma_segment_t *)malloc(
429 sizeof(bus_dma_segment_t) * dmat->common.nsegments,
431 if (dmat->segments == NULL) {
432 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
433 __func__, dmat, dmat->common.flags, ENOMEM);
437 if (flags & BUS_DMA_ZERO)
439 if (flags & BUS_DMA_NOCACHE)
440 attr = VM_MEMATTR_UNCACHEABLE;
441 else if ((flags & BUS_DMA_COHERENT) != 0 &&
442 (dmat->bounce_flags & BF_COHERENT) == 0)
444 * If we have a non-coherent tag, and are trying to allocate
445 * a coherent block of memory it needs to be uncached.
447 attr = VM_MEMATTR_UNCACHEABLE;
449 attr = VM_MEMATTR_DEFAULT;
452 * Create the map, but don't set the could bounce flag as
453 * this allocation should never bounce;
455 *mapp = alloc_dmamap(dmat, mflags);
457 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
458 __func__, dmat, dmat->common.flags, ENOMEM);
461 (*mapp)->flags = DMAMAP_FROM_DMAMEM;
465 * (dmat->alignment <= dmat->maxsize) is just a quick hack; the exact
466 * alignment guarantees of malloc need to be nailed down, and the
467 * code below should be rewritten to take that into account.
469 * In the meantime, we'll warn the user if malloc gets it wrong.
471 if ((dmat->common.maxsize <= PAGE_SIZE) &&
472 (dmat->common.alignment <= dmat->common.maxsize) &&
473 dmat->common.lowaddr >= ptoa((vm_paddr_t)Maxmem) &&
474 attr == VM_MEMATTR_DEFAULT) {
475 *vaddr = malloc(dmat->common.maxsize, M_DEVBUF, mflags);
476 } else if (dmat->common.nsegments >= btoc(dmat->common.maxsize) &&
477 dmat->common.alignment <= PAGE_SIZE &&
478 (dmat->common.boundary == 0 ||
479 dmat->common.boundary >= dmat->common.lowaddr)) {
480 /* Page-based multi-segment allocations allowed */
481 *vaddr = (void *)kmem_alloc_attr(kernel_arena,
482 dmat->common.maxsize, mflags, 0ul, dmat->common.lowaddr,
484 dmat->bounce_flags |= BF_KMEM_ALLOC;
486 *vaddr = (void *)kmem_alloc_contig(kernel_arena,
487 dmat->common.maxsize, mflags, 0ul, dmat->common.lowaddr,
488 dmat->common.alignment != 0 ? dmat->common.alignment : 1ul,
489 dmat->common.boundary, attr);
490 dmat->bounce_flags |= BF_KMEM_ALLOC;
492 if (*vaddr == NULL) {
493 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
494 __func__, dmat, dmat->common.flags, ENOMEM);
495 free(*mapp, M_DEVBUF);
497 } else if (vtophys(*vaddr) & (dmat->common.alignment - 1)) {
498 printf("bus_dmamem_alloc failed to align memory properly.\n");
501 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
502 __func__, dmat, dmat->common.flags, 0);
507 * Free a piece of memory and it's allociated dmamap, that was allocated
508 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
511 bounce_bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
515 * Check the map came from bounce_bus_dmamem_alloc, so the map
516 * should be NULL and the BF_KMEM_ALLOC flag cleared if malloc()
517 * was used and set if kmem_alloc_contig() was used.
519 if ((map->flags & DMAMAP_FROM_DMAMEM) == 0)
520 panic("bus_dmamem_free: Invalid map freed\n");
521 if ((dmat->bounce_flags & BF_KMEM_ALLOC) == 0)
522 free(vaddr, M_DEVBUF);
524 kmem_free(kernel_arena, (vm_offset_t)vaddr,
525 dmat->common.maxsize);
528 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat,
533 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf,
534 bus_size_t buflen, int flags)
539 if ((map->flags & DMAMAP_COULD_BOUNCE) != 0 && map->pagesneeded == 0) {
541 * Count the number of bounce pages
542 * needed in order to complete this transfer
545 while (buflen != 0) {
546 sgsize = MIN(buflen, dmat->common.maxsegsz);
547 if (bus_dma_run_filter(&dmat->common, curaddr)) {
549 PAGE_SIZE - (curaddr & PAGE_MASK));
555 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
560 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap,
561 void *buf, bus_size_t buflen, int flags)
564 vm_offset_t vendaddr;
568 if ((map->flags & DMAMAP_COULD_BOUNCE) != 0 && map->pagesneeded == 0) {
569 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
570 "alignment= %d", dmat->common.lowaddr,
571 ptoa((vm_paddr_t)Maxmem),
572 dmat->common.boundary, dmat->common.alignment);
573 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map,
576 * Count the number of bounce pages
577 * needed in order to complete this transfer
579 vaddr = (vm_offset_t)buf;
580 vendaddr = (vm_offset_t)buf + buflen;
582 while (vaddr < vendaddr) {
583 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK);
584 if (pmap == kernel_pmap)
585 paddr = pmap_kextract(vaddr);
587 paddr = pmap_extract(pmap, vaddr);
588 if (bus_dma_run_filter(&dmat->common, paddr) != 0) {
589 sg_len = roundup2(sg_len,
590 dmat->common.alignment);
595 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
600 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags)
603 /* Reserve Necessary Bounce Pages */
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 */
613 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, map, links);
614 mtx_unlock(&bounce_lock);
615 return (EINPROGRESS);
618 mtx_unlock(&bounce_lock);
624 * Add a single contiguous physical range to the segment list.
627 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, bus_addr_t curaddr,
628 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp)
630 bus_addr_t baddr, bmask;
634 * Make sure we don't cross any boundaries.
636 bmask = ~(dmat->common.boundary - 1);
637 if (dmat->common.boundary > 0) {
638 baddr = (curaddr + dmat->common.boundary) & bmask;
639 if (sgsize > (baddr - curaddr))
640 sgsize = (baddr - curaddr);
644 * Insert chunk into a segment, coalescing with
645 * previous segment if possible.
650 segs[seg].ds_addr = curaddr;
651 segs[seg].ds_len = sgsize;
653 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len &&
654 (segs[seg].ds_len + sgsize) <= dmat->common.maxsegsz &&
655 (dmat->common.boundary == 0 ||
656 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
657 segs[seg].ds_len += sgsize;
659 if (++seg >= dmat->common.nsegments)
661 segs[seg].ds_addr = curaddr;
662 segs[seg].ds_len = sgsize;
670 * Utility function to load a physical buffer. segp contains
671 * the starting segment on entrace, and the ending segment on exit.
674 bounce_bus_dmamap_load_phys(bus_dma_tag_t dmat, bus_dmamap_t map,
675 vm_paddr_t buf, bus_size_t buflen, int flags, bus_dma_segment_t *segs,
678 struct sync_list *sl;
680 bus_addr_t curaddr, sl_end;
684 segs = dmat->segments;
686 if ((dmat->bounce_flags & BF_COULD_BOUNCE) != 0) {
687 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags);
688 if (map->pagesneeded != 0) {
689 error = _bus_dmamap_reserve_pages(dmat, map, flags);
695 sl = map->slist + map->sync_count - 1;
700 sgsize = MIN(buflen, dmat->common.maxsegsz);
701 if (((dmat->bounce_flags & BF_COULD_BOUNCE) != 0) &&
702 map->pagesneeded != 0 &&
703 bus_dma_run_filter(&dmat->common, curaddr)) {
704 sgsize = MIN(sgsize, PAGE_SIZE - (curaddr & PAGE_MASK));
705 curaddr = add_bounce_page(dmat, map, 0, curaddr,
707 } else if ((dmat->bounce_flags & BF_COHERENT) == 0) {
708 if (map->sync_count > 0)
709 sl_end = sl->paddr + sl->datacount;
711 if (map->sync_count == 0 || curaddr != sl_end) {
712 if (++map->sync_count > dmat->common.nsegments)
717 sl->datacount = sgsize;
718 sl->pages = PHYS_TO_VM_PAGE(curaddr);
719 KASSERT(sl->pages != NULL,
720 ("%s: page at PA:0x%08lx is not in "
721 "vm_page_array", __func__, curaddr));
723 sl->datacount += sgsize;
725 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
736 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
740 * Utility function to load a linear buffer. segp contains
741 * the starting segment on entrace, and the ending segment on exit.
744 bounce_bus_dmamap_load_buffer(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
745 bus_size_t buflen, pmap_t pmap, int flags, bus_dma_segment_t *segs,
748 struct sync_list *sl;
749 bus_size_t sgsize, max_sgsize;
750 bus_addr_t curaddr, sl_pend;
751 vm_offset_t kvaddr, vaddr, sl_vend;
755 segs = dmat->segments;
757 if ((dmat->bounce_flags & BF_COULD_BOUNCE) != 0) {
758 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags);
759 if (map->pagesneeded != 0) {
760 error = _bus_dmamap_reserve_pages(dmat, map, flags);
766 sl = map->slist + map->sync_count - 1;
767 vaddr = (vm_offset_t)buf;
773 * Get the physical address for this segment.
775 if (pmap == kernel_pmap) {
776 curaddr = pmap_kextract(vaddr);
779 curaddr = pmap_extract(pmap, vaddr);
784 * Compute the segment size, and adjust counts.
786 max_sgsize = MIN(buflen, dmat->common.maxsegsz);
787 sgsize = PAGE_SIZE - (curaddr & PAGE_MASK);
788 if (((dmat->bounce_flags & BF_COULD_BOUNCE) != 0) &&
789 map->pagesneeded != 0 &&
790 bus_dma_run_filter(&dmat->common, curaddr)) {
791 sgsize = roundup2(sgsize, dmat->common.alignment);
792 sgsize = MIN(sgsize, max_sgsize);
793 curaddr = add_bounce_page(dmat, map, kvaddr, curaddr,
795 } else if ((dmat->bounce_flags & BF_COHERENT) == 0) {
796 sgsize = MIN(sgsize, max_sgsize);
797 if (map->sync_count > 0) {
798 sl_pend = sl->paddr + sl->datacount;
799 sl_vend = sl->vaddr + sl->datacount;
802 if (map->sync_count == 0 ||
803 (kvaddr != 0 && kvaddr != sl_vend) ||
804 (curaddr != sl_pend)) {
806 if (++map->sync_count > dmat->common.nsegments)
814 sl->pages = PHYS_TO_VM_PAGE(curaddr);
815 KASSERT(sl->pages != NULL,
816 ("%s: page at PA:0x%08lx is not "
817 "in vm_page_array", __func__,
820 sl->datacount = sgsize;
822 sl->datacount += sgsize;
824 sgsize = MIN(sgsize, max_sgsize);
826 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
838 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
842 bounce_bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map,
843 struct memdesc *mem, bus_dmamap_callback_t *callback, void *callback_arg)
846 if ((map->flags & DMAMAP_COULD_BOUNCE) == 0)
850 map->callback = callback;
851 map->callback_arg = callback_arg;
854 static bus_dma_segment_t *
855 bounce_bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map,
856 bus_dma_segment_t *segs, int nsegs, int error)
860 segs = dmat->segments;
865 * Release the mapping held by map.
868 bounce_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
870 struct bounce_page *bpage;
872 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
873 STAILQ_REMOVE_HEAD(&map->bpages, links);
874 free_bounce_page(dmat, bpage);
881 dma_preread_safe(vm_offset_t va, vm_size_t size)
884 * Write back any partial cachelines immediately before and
885 * after the DMA region.
887 if (va & (dcache_line_size - 1))
888 cpu_dcache_wb_range(va, 1);
889 if ((va + size) & (dcache_line_size - 1))
890 cpu_dcache_wb_range(va + size, 1);
892 cpu_dcache_inv_range(va, size);
896 dma_dcache_sync(struct sync_list *sl, bus_dmasync_op_t op)
898 uint32_t len, offset;
901 vm_offset_t va, tempva;
904 offset = sl->paddr & PAGE_MASK;
906 size = sl->datacount;
909 for ( ; size != 0; size -= len, pa += len, offset = 0, ++m) {
911 if (sl->vaddr == 0) {
912 len = min(PAGE_SIZE - offset, size);
913 tempva = pmap_quick_enter_page(m);
914 va = tempva | offset;
915 KASSERT(pa == (VM_PAGE_TO_PHYS(m) | offset),
916 ("unexpected vm_page_t phys: 0x%16lx != 0x%16lx",
917 VM_PAGE_TO_PHYS(m) | offset, pa));
924 case BUS_DMASYNC_PREWRITE:
925 case BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD:
926 cpu_dcache_wb_range(va, len);
928 case BUS_DMASYNC_PREREAD:
930 * An mbuf may start in the middle of a cacheline. There
931 * will be no cpu writes to the beginning of that line
932 * (which contains the mbuf header) while dma is in
933 * progress. Handle that case by doing a writeback of
934 * just the first cacheline before invalidating the
935 * overall buffer. Any mbuf in a chain may have this
936 * misalignment. Buffers which are not mbufs bounce if
937 * they are not aligned to a cacheline.
939 dma_preread_safe(va, len);
941 case BUS_DMASYNC_POSTREAD:
942 case BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE:
943 cpu_dcache_inv_range(va, len);
946 panic("unsupported combination of sync operations: "
951 pmap_quick_remove_page(tempva);
956 bounce_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map,
959 struct bounce_page *bpage;
960 struct sync_list *sl, *end;
961 vm_offset_t datavaddr, tempvaddr;
963 if (op == BUS_DMASYNC_POSTWRITE)
966 if ((op & BUS_DMASYNC_POSTREAD) != 0) {
968 * Wait for any DMA operations to complete before the bcopy.
973 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
974 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
975 "performing bounce", __func__, dmat, dmat->common.flags,
978 if ((op & BUS_DMASYNC_PREWRITE) != 0) {
979 while (bpage != NULL) {
981 datavaddr = bpage->datavaddr;
982 if (datavaddr == 0) {
983 tempvaddr = pmap_quick_enter_page(
985 datavaddr = tempvaddr | bpage->dataoffs;
988 bcopy((void *)datavaddr,
989 (void *)bpage->vaddr, bpage->datacount);
991 pmap_quick_remove_page(tempvaddr);
992 if ((dmat->bounce_flags & BF_COHERENT) == 0)
993 cpu_dcache_wb_range(bpage->vaddr,
995 bpage = STAILQ_NEXT(bpage, links);
997 dmat->bounce_zone->total_bounced++;
998 } else if ((op & BUS_DMASYNC_PREREAD) != 0) {
999 while (bpage != NULL) {
1000 if ((dmat->bounce_flags & BF_COHERENT) == 0)
1001 cpu_dcache_wbinv_range(bpage->vaddr,
1003 bpage = STAILQ_NEXT(bpage, links);
1007 if ((op & BUS_DMASYNC_POSTREAD) != 0) {
1008 while (bpage != NULL) {
1009 if ((dmat->bounce_flags & BF_COHERENT) == 0)
1010 cpu_dcache_inv_range(bpage->vaddr,
1013 datavaddr = bpage->datavaddr;
1014 if (datavaddr == 0) {
1015 tempvaddr = pmap_quick_enter_page(
1017 datavaddr = tempvaddr | bpage->dataoffs;
1020 bcopy((void *)bpage->vaddr,
1021 (void *)datavaddr, bpage->datacount);
1024 pmap_quick_remove_page(tempvaddr);
1025 bpage = STAILQ_NEXT(bpage, links);
1027 dmat->bounce_zone->total_bounced++;
1032 * Cache maintenance for normal (non-COHERENT non-bounce) buffers.
1034 if (map->sync_count != 0) {
1035 sl = &map->slist[0];
1036 end = &map->slist[map->sync_count];
1037 CTR3(KTR_BUSDMA, "%s: tag %p op 0x%x "
1038 "performing sync", __func__, dmat, op);
1040 for ( ; sl != end; ++sl)
1041 dma_dcache_sync(sl, op);
1044 if ((op & (BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE)) != 0) {
1046 * Wait for the bcopy to complete before any DMA operations.
1053 init_bounce_pages(void *dummy __unused)
1057 STAILQ_INIT(&bounce_zone_list);
1058 STAILQ_INIT(&bounce_map_waitinglist);
1059 STAILQ_INIT(&bounce_map_callbacklist);
1060 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
1062 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
1064 static struct sysctl_ctx_list *
1065 busdma_sysctl_tree(struct bounce_zone *bz)
1068 return (&bz->sysctl_tree);
1071 static struct sysctl_oid *
1072 busdma_sysctl_tree_top(struct bounce_zone *bz)
1075 return (bz->sysctl_tree_top);
1079 alloc_bounce_zone(bus_dma_tag_t dmat)
1081 struct bounce_zone *bz;
1083 /* Check to see if we already have a suitable zone */
1084 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
1085 if ((dmat->common.alignment <= bz->alignment) &&
1086 (dmat->common.lowaddr >= bz->lowaddr)) {
1087 dmat->bounce_zone = bz;
1092 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
1093 M_NOWAIT | M_ZERO)) == NULL)
1096 STAILQ_INIT(&bz->bounce_page_list);
1097 bz->free_bpages = 0;
1098 bz->reserved_bpages = 0;
1099 bz->active_bpages = 0;
1100 bz->lowaddr = dmat->common.lowaddr;
1101 bz->alignment = MAX(dmat->common.alignment, PAGE_SIZE);
1103 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
1105 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
1106 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
1107 dmat->bounce_zone = bz;
1109 sysctl_ctx_init(&bz->sysctl_tree);
1110 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
1111 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1113 if (bz->sysctl_tree_top == NULL) {
1114 sysctl_ctx_free(&bz->sysctl_tree);
1115 return (0); /* XXX error code? */
1118 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1119 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1120 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1121 "Total bounce pages");
1122 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1123 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1124 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1125 "Free bounce pages");
1126 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1127 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1128 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1129 "Reserved bounce pages");
1130 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1131 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1132 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1133 "Active bounce pages");
1134 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1135 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1136 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1137 "Total bounce requests");
1138 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1139 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1140 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1141 "Total bounce requests that were deferred");
1142 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1143 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1144 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1145 SYSCTL_ADD_UAUTO(busdma_sysctl_tree(bz),
1146 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1147 "alignment", CTLFLAG_RD, &bz->alignment, "");
1153 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1155 struct bounce_zone *bz;
1158 bz = dmat->bounce_zone;
1160 while (numpages > 0) {
1161 struct bounce_page *bpage;
1163 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1168 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1169 M_NOWAIT, 0ul, bz->lowaddr, PAGE_SIZE, 0);
1170 if (bpage->vaddr == 0) {
1171 free(bpage, M_DEVBUF);
1174 bpage->busaddr = pmap_kextract(bpage->vaddr);
1175 mtx_lock(&bounce_lock);
1176 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1180 mtx_unlock(&bounce_lock);
1188 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1190 struct bounce_zone *bz;
1193 mtx_assert(&bounce_lock, MA_OWNED);
1194 bz = dmat->bounce_zone;
1195 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1196 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1197 return (map->pagesneeded - (map->pagesreserved + pages));
1198 bz->free_bpages -= pages;
1199 bz->reserved_bpages += pages;
1200 map->pagesreserved += pages;
1201 pages = map->pagesneeded - map->pagesreserved;
1207 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1208 bus_addr_t addr, bus_size_t size)
1210 struct bounce_zone *bz;
1211 struct bounce_page *bpage;
1213 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1214 KASSERT((map->flags & DMAMAP_COULD_BOUNCE) != 0,
1215 ("add_bounce_page: bad map %p", map));
1217 bz = dmat->bounce_zone;
1218 if (map->pagesneeded == 0)
1219 panic("add_bounce_page: map doesn't need any pages");
1222 if (map->pagesreserved == 0)
1223 panic("add_bounce_page: map doesn't need any pages");
1224 map->pagesreserved--;
1226 mtx_lock(&bounce_lock);
1227 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1229 panic("add_bounce_page: free page list is empty");
1231 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1232 bz->reserved_bpages--;
1233 bz->active_bpages++;
1234 mtx_unlock(&bounce_lock);
1236 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) {
1237 /* Page offset needs to be preserved. */
1238 bpage->vaddr |= addr & PAGE_MASK;
1239 bpage->busaddr |= addr & PAGE_MASK;
1241 bpage->datavaddr = vaddr;
1242 bpage->datapage = PHYS_TO_VM_PAGE(addr);
1243 bpage->dataoffs = addr & PAGE_MASK;
1244 bpage->datacount = size;
1245 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1246 return (bpage->busaddr);
1250 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1252 struct bus_dmamap *map;
1253 struct bounce_zone *bz;
1255 bz = dmat->bounce_zone;
1256 bpage->datavaddr = 0;
1257 bpage->datacount = 0;
1258 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) {
1260 * Reset the bounce page to start at offset 0. Other uses
1261 * of this bounce page may need to store a full page of
1262 * data and/or assume it starts on a page boundary.
1264 bpage->vaddr &= ~PAGE_MASK;
1265 bpage->busaddr &= ~PAGE_MASK;
1268 mtx_lock(&bounce_lock);
1269 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1271 bz->active_bpages--;
1272 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1273 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1274 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1275 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1277 busdma_swi_pending = 1;
1278 bz->total_deferred++;
1279 swi_sched(vm_ih, 0);
1282 mtx_unlock(&bounce_lock);
1289 struct bus_dmamap *map;
1291 mtx_lock(&bounce_lock);
1292 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1293 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1294 mtx_unlock(&bounce_lock);
1296 (dmat->common.lockfunc)(dmat->common.lockfuncarg, BUS_DMA_LOCK);
1297 bus_dmamap_load_mem(map->dmat, map, &map->mem,
1298 map->callback, map->callback_arg, BUS_DMA_WAITOK);
1299 (dmat->common.lockfunc)(dmat->common.lockfuncarg,
1301 mtx_lock(&bounce_lock);
1303 mtx_unlock(&bounce_lock);
1306 struct bus_dma_impl bus_dma_bounce_impl = {
1307 .tag_create = bounce_bus_dma_tag_create,
1308 .tag_destroy = bounce_bus_dma_tag_destroy,
1309 .map_create = bounce_bus_dmamap_create,
1310 .map_destroy = bounce_bus_dmamap_destroy,
1311 .mem_alloc = bounce_bus_dmamem_alloc,
1312 .mem_free = bounce_bus_dmamem_free,
1313 .load_phys = bounce_bus_dmamap_load_phys,
1314 .load_buffer = bounce_bus_dmamap_load_buffer,
1315 .load_ma = bus_dmamap_load_ma_triv,
1316 .map_waitok = bounce_bus_dmamap_waitok,
1317 .map_complete = bounce_bus_dmamap_complete,
1318 .map_unload = bounce_bus_dmamap_unload,
1319 .map_sync = bounce_bus_dmamap_sync