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>
56 #define MAX_BPAGES 512
58 #define MAX_BPAGES 8192
60 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
61 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
71 bus_dma_filter_t *filter;
79 bus_dma_lock_t *lockfunc;
81 bus_dma_segment_t *segments;
82 struct bounce_zone *bounce_zone;
86 vm_offset_t vaddr; /* kva of bounce buffer */
87 bus_addr_t busaddr; /* Physical address */
88 vm_offset_t datavaddr; /* kva of client data */
89 bus_addr_t dataaddr; /* client physical address */
90 bus_size_t datacount; /* client data count */
91 STAILQ_ENTRY(bounce_page) links;
94 int busdma_swi_pending;
97 STAILQ_ENTRY(bounce_zone) links;
98 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
106 bus_size_t alignment;
110 struct sysctl_ctx_list sysctl_tree;
111 struct sysctl_oid *sysctl_tree_top;
114 static struct mtx bounce_lock;
115 static int total_bpages;
116 static int busdma_zonecount;
117 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
119 static SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
120 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
121 "Total bounce pages");
124 struct bp_list bpages;
129 bus_dmamap_callback_t *callback;
131 STAILQ_ENTRY(bus_dmamap) links;
134 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
135 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
136 static struct bus_dmamap nobounce_dmamap, contig_dmamap;
138 static void init_bounce_pages(void *dummy);
139 static int alloc_bounce_zone(bus_dma_tag_t dmat);
140 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
141 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
143 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
144 vm_offset_t vaddr, bus_addr_t addr,
146 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
147 int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
148 static void _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
149 pmap_t pmap, void *buf, bus_size_t buflen,
151 static void _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map,
152 vm_paddr_t buf, bus_size_t buflen,
154 static int _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
159 #define pmap_kextract pmap_kextract_ma
163 * Return true if a match is made.
165 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'.
167 * If paddr is within the bounds of the dma tag then call the filter callback
168 * to check for a match, if there is no filter callback then assume a match.
171 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
178 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr)
179 || ((paddr & (dmat->alignment - 1)) != 0))
180 && (dmat->filter == NULL
181 || (*dmat->filter)(dmat->filterarg, paddr) != 0))
185 } while (retval == 0 && dmat != NULL);
190 * Convenience function for manipulating driver locks from busdma (during
191 * busdma_swi, for example). Drivers that don't provide their own locks
192 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own
193 * non-mutex locking scheme don't have to use this at all.
196 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
200 dmtx = (struct mtx *)arg;
209 panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
214 * dflt_lock should never get called. It gets put into the dma tag when
215 * lockfunc == NULL, which is only valid if the maps that are associated
216 * with the tag are meant to never be defered.
217 * XXX Should have a way to identify which driver is responsible here.
220 dflt_lock(void *arg, bus_dma_lock_op_t op)
222 panic("driver error: busdma dflt_lock called");
226 * Allocate a device specific dma_tag.
229 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
230 bus_size_t boundary, bus_addr_t lowaddr,
231 bus_addr_t highaddr, bus_dma_filter_t *filter,
232 void *filterarg, bus_size_t maxsize, int nsegments,
233 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
234 void *lockfuncarg, bus_dma_tag_t *dmat)
236 bus_dma_tag_t newtag;
239 /* Always enforce at least a 4GB (2GB for PAE) boundary. */
240 #if defined(__amd64__)
241 if (boundary == 0 || boundary > ((bus_addr_t)1 << 32))
242 boundary = (bus_size_t)1 << 32;
244 if (boundary == 0 || boundary > ((bus_addr_t)1 << 31))
245 boundary = (bus_size_t)1 << 31;
247 /* Basic sanity checking */
248 if (boundary != 0 && boundary < maxsegsz)
255 /* Return a NULL tag on failure */
258 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF,
260 if (newtag == NULL) {
261 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
262 __func__, newtag, 0, ENOMEM);
266 newtag->parent = parent;
267 newtag->alignment = alignment;
268 newtag->boundary = boundary;
269 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
270 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
271 newtag->filter = filter;
272 newtag->filterarg = filterarg;
273 newtag->maxsize = maxsize;
274 newtag->nsegments = nsegments;
275 newtag->maxsegsz = maxsegsz;
276 newtag->flags = flags;
277 newtag->ref_count = 1; /* Count ourself */
278 newtag->map_count = 0;
279 if (lockfunc != NULL) {
280 newtag->lockfunc = lockfunc;
281 newtag->lockfuncarg = lockfuncarg;
283 newtag->lockfunc = dflt_lock;
284 newtag->lockfuncarg = NULL;
286 newtag->segments = NULL;
288 /* Take into account any restrictions imposed by our parent tag */
289 if (parent != NULL) {
290 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
291 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
292 if (newtag->boundary == 0)
293 newtag->boundary = parent->boundary;
294 else if (parent->boundary != 0)
295 newtag->boundary = MIN(parent->boundary,
297 if ((newtag->filter != NULL) ||
298 ((parent->flags & BUS_DMA_COULD_BOUNCE) != 0))
299 newtag->flags |= BUS_DMA_COULD_BOUNCE;
300 if (newtag->filter == NULL) {
302 * Short circuit looking at our parent directly
303 * since we have encapsulated all of its information
305 newtag->filter = parent->filter;
306 newtag->filterarg = parent->filterarg;
307 newtag->parent = parent->parent;
309 if (newtag->parent != NULL)
310 atomic_add_int(&parent->ref_count, 1);
313 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem)
314 || newtag->alignment > 1)
315 newtag->flags |= BUS_DMA_COULD_BOUNCE;
317 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
318 (flags & BUS_DMA_ALLOCNOW) != 0) {
319 struct bounce_zone *bz;
323 if ((error = alloc_bounce_zone(newtag)) != 0) {
324 free(newtag, M_DEVBUF);
327 bz = newtag->bounce_zone;
329 if (ptoa(bz->total_bpages) < maxsize) {
332 pages = atop(maxsize) - bz->total_bpages;
334 /* Add pages to our bounce pool */
335 if (alloc_bounce_pages(newtag, pages) < pages)
338 /* Performed initial allocation */
339 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
343 free(newtag, M_DEVBUF);
347 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
348 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
353 bus_dma_tag_destroy(bus_dma_tag_t dmat)
355 bus_dma_tag_t dmat_copy;
363 if (dmat->map_count != 0) {
368 while (dmat != NULL) {
369 bus_dma_tag_t parent;
371 parent = dmat->parent;
372 atomic_subtract_int(&dmat->ref_count, 1);
373 if (dmat->ref_count == 0) {
374 if (dmat->segments != NULL)
375 free(dmat->segments, M_DEVBUF);
376 free(dmat, M_DEVBUF);
378 * Last reference count, so
379 * release our reference
380 * count on our parent.
388 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
393 * Allocate a handle for mapping from kva/uva/physical
394 * address space into bus device space.
397 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
403 if (dmat->segments == NULL) {
404 dmat->segments = (bus_dma_segment_t *)malloc(
405 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
407 if (dmat->segments == NULL) {
408 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
409 __func__, dmat, ENOMEM);
415 * Bouncing might be required if the driver asks for an active
416 * exclusion region, a data alignment that is stricter than 1, and/or
417 * an active address boundary.
419 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
422 struct bounce_zone *bz;
425 if (dmat->bounce_zone == NULL) {
426 if ((error = alloc_bounce_zone(dmat)) != 0)
429 bz = dmat->bounce_zone;
431 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
434 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
435 __func__, dmat, ENOMEM);
439 /* Initialize the new map */
440 STAILQ_INIT(&((*mapp)->bpages));
443 * Attempt to add pages to our pool on a per-instance
444 * basis up to a sane limit.
446 if (dmat->alignment > 1)
447 maxpages = MAX_BPAGES;
449 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
450 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
451 || (bz->map_count > 0 && bz->total_bpages < maxpages)) {
454 pages = MAX(atop(dmat->maxsize), 1);
455 pages = MIN(maxpages - bz->total_bpages, pages);
456 pages = MAX(pages, 1);
457 if (alloc_bounce_pages(dmat, pages) < pages)
460 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
462 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
473 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
474 __func__, dmat, dmat->flags, error);
479 * Destroy a handle for mapping from kva/uva/physical
480 * address space into bus device space.
483 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
485 if (map != NULL && map != &nobounce_dmamap && map != &contig_dmamap) {
486 if (STAILQ_FIRST(&map->bpages) != NULL) {
487 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
488 __func__, dmat, EBUSY);
491 if (dmat->bounce_zone)
492 dmat->bounce_zone->map_count--;
496 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
502 * Allocate a piece of memory that can be efficiently mapped into
503 * bus device space based on the constraints lited in the dma tag.
504 * A dmamap to for use with dmamap_load is also allocated.
507 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
513 if (flags & BUS_DMA_NOWAIT)
518 /* If we succeed, no mapping/bouncing will be required */
521 if (dmat->segments == NULL) {
522 dmat->segments = (bus_dma_segment_t *)malloc(
523 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
525 if (dmat->segments == NULL) {
526 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
527 __func__, dmat, dmat->flags, ENOMEM);
531 if (flags & BUS_DMA_ZERO)
533 if (flags & BUS_DMA_NOCACHE)
534 attr = VM_MEMATTR_UNCACHEABLE;
536 attr = VM_MEMATTR_DEFAULT;
540 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact
541 * alignment guarantees of malloc need to be nailed down, and the
542 * code below should be rewritten to take that into account.
544 * In the meantime, we'll warn the user if malloc gets it wrong.
546 if ((dmat->maxsize <= PAGE_SIZE) &&
547 (dmat->alignment < dmat->maxsize) &&
548 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem) &&
549 attr == VM_MEMATTR_DEFAULT) {
550 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
551 } else if (dmat->nsegments >= btoc(dmat->maxsize) &&
552 dmat->alignment <= PAGE_SIZE &&
553 (dmat->boundary == 0 || dmat->boundary >= dmat->lowaddr)) {
554 /* Page-based multi-segment allocations allowed */
555 *vaddr = (void *)kmem_alloc_attr(kernel_map, dmat->maxsize,
556 mflags, 0ul, dmat->lowaddr, attr);
557 *mapp = &contig_dmamap;
559 *vaddr = (void *)kmem_alloc_contig(kernel_map, dmat->maxsize,
560 mflags, 0ul, dmat->lowaddr, dmat->alignment ?
561 dmat->alignment : 1ul, dmat->boundary, attr);
562 *mapp = &contig_dmamap;
564 if (*vaddr == NULL) {
565 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
566 __func__, dmat, dmat->flags, ENOMEM);
568 } else if (vtophys(*vaddr) & (dmat->alignment - 1)) {
569 printf("bus_dmamem_alloc failed to align memory properly.\n");
571 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
572 __func__, dmat, dmat->flags, 0);
577 * Free a piece of memory and it's allociated dmamap, that was allocated
578 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
581 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
584 * dmamem does not need to be bounced, so the map should be
585 * NULL if malloc() was used and contig_dmamap if
586 * kmem_alloc_contig() was used.
588 if (!(map == NULL || map == &contig_dmamap))
589 panic("bus_dmamem_free: Invalid map freed\n");
591 free(vaddr, M_DEVBUF);
593 kmem_free(kernel_map, (vm_offset_t)vaddr, dmat->maxsize);
594 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
598 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf,
599 bus_size_t buflen, int flags)
604 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) {
606 * Count the number of bounce pages
607 * needed in order to complete this transfer
610 while (buflen != 0) {
611 sgsize = MIN(buflen, dmat->maxsegsz);
612 if (run_filter(dmat, curaddr)) {
613 sgsize = MIN(sgsize, PAGE_SIZE);
619 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
624 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap,
625 void *buf, bus_size_t buflen, int flags)
628 vm_offset_t vendaddr;
631 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) {
632 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
633 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
634 dmat->boundary, dmat->alignment);
635 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d",
636 map, &nobounce_dmamap, map->pagesneeded);
638 * Count the number of bounce pages
639 * needed in order to complete this transfer
641 vaddr = (vm_offset_t)buf;
642 vendaddr = (vm_offset_t)buf + buflen;
644 while (vaddr < vendaddr) {
647 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK);
648 if (pmap == kernel_pmap)
649 paddr = pmap_kextract(vaddr);
651 paddr = pmap_extract(pmap, vaddr);
652 if (run_filter(dmat, paddr) != 0) {
653 sg_len = roundup2(sg_len, dmat->alignment);
658 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
663 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags)
666 /* Reserve Necessary Bounce Pages */
667 mtx_lock(&bounce_lock);
668 if (flags & BUS_DMA_NOWAIT) {
669 if (reserve_bounce_pages(dmat, map, 0) != 0) {
670 mtx_unlock(&bounce_lock);
674 if (reserve_bounce_pages(dmat, map, 1) != 0) {
675 /* Queue us for resources */
676 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, map, links);
677 mtx_unlock(&bounce_lock);
678 return (EINPROGRESS);
681 mtx_unlock(&bounce_lock);
687 * Add a single contiguous physical range to the segment list.
690 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, bus_addr_t curaddr,
691 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp)
693 bus_addr_t baddr, bmask;
697 * Make sure we don't cross any boundaries.
699 bmask = ~(dmat->boundary - 1);
700 if (dmat->boundary > 0) {
701 baddr = (curaddr + dmat->boundary) & bmask;
702 if (sgsize > (baddr - curaddr))
703 sgsize = (baddr - curaddr);
707 * Insert chunk into a segment, coalescing with
708 * previous segment if possible.
713 segs[seg].ds_addr = curaddr;
714 segs[seg].ds_len = sgsize;
716 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len &&
717 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
718 (dmat->boundary == 0 ||
719 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
720 segs[seg].ds_len += sgsize;
722 if (++seg >= dmat->nsegments)
724 segs[seg].ds_addr = curaddr;
725 segs[seg].ds_len = sgsize;
733 * Utility function to load a physical buffer. segp contains
734 * the starting segment on entrace, and the ending segment on exit.
737 _bus_dmamap_load_phys(bus_dma_tag_t dmat,
739 vm_paddr_t buf, bus_size_t buflen,
741 bus_dma_segment_t *segs,
748 if (map == NULL || map == &contig_dmamap)
749 map = &nobounce_dmamap;
752 segs = dmat->segments;
754 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
755 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags);
756 if (map->pagesneeded != 0) {
757 error = _bus_dmamap_reserve_pages(dmat, map, flags);
765 sgsize = MIN(buflen, dmat->maxsegsz);
766 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
767 map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
768 sgsize = MIN(sgsize, PAGE_SIZE);
769 curaddr = add_bounce_page(dmat, map, 0, curaddr,
772 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
783 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
787 * Utility function to load a linear buffer. segp contains
788 * the starting segment on entrace, and the ending segment on exit.
791 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
793 void *buf, bus_size_t buflen,
796 bus_dma_segment_t *segs,
804 if (map == NULL || map == &contig_dmamap)
805 map = &nobounce_dmamap;
808 segs = dmat->segments;
810 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
811 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags);
812 if (map->pagesneeded != 0) {
813 error = _bus_dmamap_reserve_pages(dmat, map, flags);
819 vaddr = (vm_offset_t)buf;
822 bus_size_t max_sgsize;
825 * Get the physical address for this segment.
827 if (pmap == kernel_pmap)
828 curaddr = pmap_kextract(vaddr);
830 curaddr = pmap_extract(pmap, vaddr);
833 * Compute the segment size, and adjust counts.
835 max_sgsize = MIN(buflen, dmat->maxsegsz);
836 sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK);
837 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
838 map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
839 sgsize = roundup2(sgsize, dmat->alignment);
840 sgsize = MIN(sgsize, max_sgsize);
841 curaddr = add_bounce_page(dmat, map, vaddr, curaddr,
844 sgsize = MIN(sgsize, max_sgsize);
846 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
857 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
861 __bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map,
862 struct memdesc *mem, bus_dmamap_callback_t *callback,
868 map->callback = callback;
869 map->callback_arg = callback_arg;
874 _bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map,
875 bus_dma_segment_t *segs, int nsegs, int error)
879 segs = dmat->segments;
884 * Release the mapping held by map.
887 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
889 struct bounce_page *bpage;
891 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
892 STAILQ_REMOVE_HEAD(&map->bpages, links);
893 free_bounce_page(dmat, bpage);
898 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
900 struct bounce_page *bpage;
902 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
904 * Handle data bouncing. We might also
905 * want to add support for invalidating
906 * the caches on broken hardware
908 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
909 "performing bounce", __func__, op, dmat, dmat->flags);
911 if (op & BUS_DMASYNC_PREWRITE) {
912 while (bpage != NULL) {
913 if (bpage->datavaddr != 0)
914 bcopy((void *)bpage->datavaddr,
915 (void *)bpage->vaddr,
918 physcopyout(bpage->dataaddr,
919 (void *)bpage->vaddr,
921 bpage = STAILQ_NEXT(bpage, links);
923 dmat->bounce_zone->total_bounced++;
926 if (op & BUS_DMASYNC_POSTREAD) {
927 while (bpage != NULL) {
928 if (bpage->datavaddr != 0)
929 bcopy((void *)bpage->vaddr,
930 (void *)bpage->datavaddr,
933 physcopyin((void *)bpage->vaddr,
936 bpage = STAILQ_NEXT(bpage, links);
938 dmat->bounce_zone->total_bounced++;
944 init_bounce_pages(void *dummy __unused)
948 STAILQ_INIT(&bounce_zone_list);
949 STAILQ_INIT(&bounce_map_waitinglist);
950 STAILQ_INIT(&bounce_map_callbacklist);
951 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
953 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
955 static struct sysctl_ctx_list *
956 busdma_sysctl_tree(struct bounce_zone *bz)
958 return (&bz->sysctl_tree);
961 static struct sysctl_oid *
962 busdma_sysctl_tree_top(struct bounce_zone *bz)
964 return (bz->sysctl_tree_top);
967 #if defined(__amd64__) || defined(PAE)
968 #define SYSCTL_ADD_BUS_SIZE_T SYSCTL_ADD_UQUAD
970 #define SYSCTL_ADD_BUS_SIZE_T(ctx, parent, nbr, name, flag, ptr, desc) \
971 SYSCTL_ADD_UINT(ctx, parent, nbr, name, flag, ptr, 0, desc)
975 alloc_bounce_zone(bus_dma_tag_t dmat)
977 struct bounce_zone *bz;
979 /* Check to see if we already have a suitable zone */
980 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
981 if ((dmat->alignment <= bz->alignment)
982 && (dmat->lowaddr >= bz->lowaddr)) {
983 dmat->bounce_zone = bz;
988 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
989 M_NOWAIT | M_ZERO)) == NULL)
992 STAILQ_INIT(&bz->bounce_page_list);
994 bz->reserved_bpages = 0;
995 bz->active_bpages = 0;
996 bz->lowaddr = dmat->lowaddr;
997 bz->alignment = MAX(dmat->alignment, PAGE_SIZE);
999 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
1001 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
1002 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
1003 dmat->bounce_zone = bz;
1005 sysctl_ctx_init(&bz->sysctl_tree);
1006 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
1007 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1009 if (bz->sysctl_tree_top == NULL) {
1010 sysctl_ctx_free(&bz->sysctl_tree);
1011 return (0); /* XXX error code? */
1014 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1015 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1016 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1017 "Total bounce pages");
1018 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1019 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1020 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1021 "Free bounce pages");
1022 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1023 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1024 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1025 "Reserved bounce pages");
1026 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1027 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1028 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1029 "Active bounce pages");
1030 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1031 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1032 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1033 "Total bounce requests");
1034 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1035 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1036 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1037 "Total bounce requests that were deferred");
1038 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1039 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1040 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1041 SYSCTL_ADD_BUS_SIZE_T(busdma_sysctl_tree(bz),
1042 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1043 "alignment", CTLFLAG_RD, &bz->alignment, "");
1049 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1051 struct bounce_zone *bz;
1054 bz = dmat->bounce_zone;
1056 while (numpages > 0) {
1057 struct bounce_page *bpage;
1059 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1064 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1069 if (bpage->vaddr == 0) {
1070 free(bpage, M_DEVBUF);
1073 bpage->busaddr = pmap_kextract(bpage->vaddr);
1074 mtx_lock(&bounce_lock);
1075 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1079 mtx_unlock(&bounce_lock);
1087 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1089 struct bounce_zone *bz;
1092 mtx_assert(&bounce_lock, MA_OWNED);
1093 bz = dmat->bounce_zone;
1094 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1095 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1096 return (map->pagesneeded - (map->pagesreserved + pages));
1097 bz->free_bpages -= pages;
1098 bz->reserved_bpages += pages;
1099 map->pagesreserved += pages;
1100 pages = map->pagesneeded - map->pagesreserved;
1106 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1107 bus_addr_t addr, bus_size_t size)
1109 struct bounce_zone *bz;
1110 struct bounce_page *bpage;
1112 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1113 KASSERT(map != NULL && map != &nobounce_dmamap && map != &contig_dmamap,
1114 ("add_bounce_page: bad map %p", map));
1116 bz = dmat->bounce_zone;
1117 if (map->pagesneeded == 0)
1118 panic("add_bounce_page: map doesn't need any pages");
1121 if (map->pagesreserved == 0)
1122 panic("add_bounce_page: map doesn't need any pages");
1123 map->pagesreserved--;
1125 mtx_lock(&bounce_lock);
1126 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1128 panic("add_bounce_page: free page list is empty");
1130 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1131 bz->reserved_bpages--;
1132 bz->active_bpages++;
1133 mtx_unlock(&bounce_lock);
1135 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1136 /* Page offset needs to be preserved. */
1137 bpage->vaddr |= vaddr & PAGE_MASK;
1138 bpage->busaddr |= vaddr & PAGE_MASK;
1140 bpage->datavaddr = vaddr;
1141 bpage->dataaddr = addr;
1142 bpage->datacount = size;
1143 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1144 return (bpage->busaddr);
1148 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1150 struct bus_dmamap *map;
1151 struct bounce_zone *bz;
1153 bz = dmat->bounce_zone;
1154 bpage->datavaddr = 0;
1155 bpage->datacount = 0;
1156 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1158 * Reset the bounce page to start at offset 0. Other uses
1159 * of this bounce page may need to store a full page of
1160 * data and/or assume it starts on a page boundary.
1162 bpage->vaddr &= ~PAGE_MASK;
1163 bpage->busaddr &= ~PAGE_MASK;
1166 mtx_lock(&bounce_lock);
1167 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1169 bz->active_bpages--;
1170 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1171 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1172 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1173 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1175 busdma_swi_pending = 1;
1176 bz->total_deferred++;
1177 swi_sched(vm_ih, 0);
1180 mtx_unlock(&bounce_lock);
1187 struct bus_dmamap *map;
1189 mtx_lock(&bounce_lock);
1190 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1191 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1192 mtx_unlock(&bounce_lock);
1194 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1195 bus_dmamap_load_mem(map->dmat, map, &map->mem,
1196 map->callback, map->callback_arg,
1198 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1199 mtx_lock(&bounce_lock);
1201 mtx_unlock(&bounce_lock);