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
26 * $FreeBSD: src/sys/i386/i386/busdma_machdep.c,v 1.16.2.2 2003/01/23 00:55:27 scottl Exp $
27 * $DragonFly: src/sys/platform/pc32/i386/busdma_machdep.c,v 1.16 2006/09/13 18:45:12 swildner Exp $
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/malloc.h>
35 #include <sys/thread2.h>
38 #include <vm/vm_page.h>
40 /* XXX needed for to access pmap to convert per-proc virtual to physical */
43 #include <vm/vm_map.h>
45 #include <machine/bus.h>
46 #include <machine/md_var.h>
48 #define MAX_BPAGES 128
56 bus_dma_filter_t *filter;
64 bus_dma_segment_t *segments;
68 vm_offset_t vaddr; /* kva of bounce buffer */
69 bus_addr_t busaddr; /* Physical address */
70 vm_offset_t datavaddr; /* kva of client data */
71 bus_size_t datacount; /* client data count */
72 STAILQ_ENTRY(bounce_page) links;
75 int busdma_swi_pending;
77 static STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
78 static int free_bpages;
79 static int reserved_bpages;
80 static int active_bpages;
81 static int total_bpages;
82 static bus_addr_t bounce_lowaddr = BUS_SPACE_MAXADDR;
85 struct bp_list bpages;
89 void *buf; /* unmapped buffer pointer */
90 bus_size_t buflen; /* unmapped buffer length */
91 bus_dmamap_callback_t *callback;
93 STAILQ_ENTRY(bus_dmamap) links;
96 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
97 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
98 static struct bus_dmamap nobounce_dmamap;
100 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
101 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map);
102 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
103 vm_offset_t vaddr, bus_size_t size);
104 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
105 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
108 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
114 if (paddr > dmat->lowaddr
115 && paddr <= dmat->highaddr
116 && (dmat->filter == NULL
117 || (*dmat->filter)(dmat->filterarg, paddr) != 0))
121 } while (retval == 0 && dmat != NULL);
125 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
127 * Allocate a device specific dma_tag.
130 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
131 bus_size_t boundary, bus_addr_t lowaddr,
132 bus_addr_t highaddr, bus_dma_filter_t *filter,
133 void *filterarg, bus_size_t maxsize, int nsegments,
134 bus_size_t maxsegsz, int flags, bus_dma_tag_t *dmat)
136 bus_dma_tag_t newtag;
139 /* Return a NULL tag on failure */
142 newtag = kmalloc(sizeof(*newtag), M_DEVBUF, M_INTWAIT);
144 newtag->parent = parent;
145 newtag->alignment = alignment;
146 newtag->boundary = boundary;
147 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
148 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
149 newtag->filter = filter;
150 newtag->filterarg = filterarg;
151 newtag->maxsize = maxsize;
152 newtag->nsegments = nsegments;
153 newtag->maxsegsz = maxsegsz;
154 newtag->flags = flags;
155 newtag->ref_count = 1; /* Count ourself */
156 newtag->map_count = 0;
157 newtag->segments = NULL;
159 /* Take into account any restrictions imposed by our parent tag */
160 if (parent != NULL) {
161 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
162 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
164 * XXX Not really correct??? Probably need to honor boundary
165 * all the way up the inheritence chain.
167 newtag->boundary = MAX(parent->boundary, newtag->boundary);
168 if (newtag->filter == NULL) {
170 * Short circuit looking at our parent directly
171 * since we have encapsulated all of its information
173 newtag->filter = parent->filter;
174 newtag->filterarg = parent->filterarg;
175 newtag->parent = parent->parent;
177 if (newtag->parent != NULL) {
182 if (newtag->lowaddr < ptoa(Maxmem) &&
183 (flags & BUS_DMA_ALLOCNOW) != 0) {
186 if (lowaddr > bounce_lowaddr) {
188 * Go through the pool and kill any pages
189 * that don't reside below lowaddr.
191 panic("bus_dma_tag_create: page reallocation "
194 if (ptoa(total_bpages) < maxsize) {
197 pages = atop(maxsize) - total_bpages;
199 /* Add pages to our bounce pool */
200 if (alloc_bounce_pages(newtag, pages) < pages)
203 /* Performed initial allocation */
204 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
208 kfree(newtag, M_DEVBUF);
216 bus_dma_tag_destroy(bus_dma_tag_t dmat)
220 if (dmat->map_count != 0)
223 while (dmat != NULL) {
224 bus_dma_tag_t parent;
226 parent = dmat->parent;
228 if (dmat->ref_count == 0) {
229 if (dmat->segments != NULL)
230 kfree(dmat->segments, M_DEVBUF);
231 kfree(dmat, M_DEVBUF);
233 * Last reference count, so
234 * release our reference
235 * count on our parent.
246 * Allocate a handle for mapping from kva/uva/physical
247 * address space into bus device space.
250 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
256 if (dmat->segments == NULL) {
257 KKASSERT(dmat->nsegments && dmat->nsegments < 16384);
258 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) *
259 dmat->nsegments, M_DEVBUF, M_INTWAIT);
262 if (dmat->lowaddr < ptoa(Maxmem)) {
266 *mapp = kmalloc(sizeof(**mapp), M_DEVBUF, M_INTWAIT);
270 /* Initialize the new map */
271 bzero(*mapp, sizeof(**mapp));
272 STAILQ_INIT(&((*mapp)->bpages));
275 * Attempt to add pages to our pool on a per-instance
276 * basis up to a sane limit.
278 maxpages = MIN(MAX_BPAGES, Maxmem - atop(dmat->lowaddr));
279 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
280 || (dmat->map_count > 0
281 && total_bpages < maxpages)) {
284 if (dmat->lowaddr > bounce_lowaddr) {
286 * Go through the pool and kill any pages
287 * that don't reside below lowaddr.
289 panic("bus_dmamap_create: page reallocation "
292 pages = atop(dmat->maxsize);
293 pages = MIN(maxpages - total_bpages, pages);
294 error = alloc_bounce_pages(dmat, pages);
296 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
298 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
312 * Destroy a handle for mapping from kva/uva/physical
313 * address space into bus device space.
316 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
319 if (STAILQ_FIRST(&map->bpages) != NULL)
321 kfree(map, M_DEVBUF);
329 * Allocate a piece of memory that can be efficiently mapped into
330 * bus device space based on the constraints lited in the dma tag.
332 * mapp is degenerate. By definition this allocation should not require
333 * bounce buffers so do not allocate a dma map.
336 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
340 /* If we succeed, no mapping/bouncing will be required */
343 if (dmat->segments == NULL) {
344 KKASSERT(dmat->nsegments < 16384);
345 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) *
346 dmat->nsegments, M_DEVBUF, M_INTWAIT);
349 if (flags & BUS_DMA_NOWAIT)
353 if (flags & BUS_DMA_ZERO)
356 if ((dmat->maxsize <= PAGE_SIZE) &&
357 dmat->lowaddr >= ptoa(Maxmem)) {
358 *vaddr = kmalloc(dmat->maxsize, M_DEVBUF, mflags);
360 * XXX Check whether the allocation crossed a page boundary
361 * and retry with power-of-2 alignment in that case.
363 if ((((intptr_t)*vaddr) & PAGE_MASK) !=
364 (((intptr_t)*vaddr + dmat->maxsize) & PAGE_MASK)) {
366 kfree(*vaddr, M_DEVBUF);
367 /* XXX check for overflow? */
368 for (size = 1; size <= dmat->maxsize; size <<= 1)
370 *vaddr = kmalloc(size, M_DEVBUF, mflags);
374 * XXX Use Contigmalloc until it is merged into this facility
375 * and handles multi-seg allocations. Nobody is doing
376 * multi-seg allocations yet though.
378 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
379 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
388 * Free a piece of memory and it's allociated dmamap, that was allocated
389 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
392 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
395 * dmamem does not need to be bounced, so the map should be
399 panic("bus_dmamem_free: Invalid map freed\n");
400 if ((dmat->maxsize <= PAGE_SIZE) &&
401 dmat->lowaddr >= ptoa(Maxmem))
402 kfree(vaddr, M_DEVBUF);
404 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
407 #define BUS_DMAMAP_NSEGS ((BUS_SPACE_MAXSIZE / PAGE_SIZE) + 1)
410 * Map the buffer buf into bus space using the dmamap map.
413 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
414 bus_size_t buflen, bus_dmamap_callback_t *callback,
415 void *callback_arg, int flags)
419 bus_dma_segment_t *sg;
422 vm_paddr_t nextpaddr;
425 map = &nobounce_dmamap;
429 * If we are being called during a callback, pagesneeded will
430 * be non-zero, so we can avoid doing the work twice.
432 if (dmat->lowaddr < ptoa(Maxmem) &&
433 map->pagesneeded == 0) {
434 vm_offset_t vendaddr;
437 * Count the number of bounce pages
438 * needed in order to complete this transfer
440 vaddr = trunc_page((vm_offset_t)buf);
441 vendaddr = (vm_offset_t)buf + buflen;
443 while (vaddr < vendaddr) {
444 paddr = pmap_kextract(vaddr);
445 if (run_filter(dmat, paddr) != 0) {
453 /* Reserve Necessary Bounce Pages */
454 if (map->pagesneeded != 0) {
456 if (reserve_bounce_pages(dmat, map) != 0) {
458 /* Queue us for resources */
461 map->buflen = buflen;
462 map->callback = callback;
463 map->callback_arg = callback_arg;
465 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, map, links);
468 return (EINPROGRESS);
473 vaddr = (vm_offset_t)buf;
482 paddr = pmap_kextract(vaddr);
483 size = PAGE_SIZE - (paddr & PAGE_MASK);
487 if (map->pagesneeded != 0 && run_filter(dmat, paddr)) {
488 paddr = add_bounce_page(dmat, map, vaddr, size);
491 if (sg->ds_len == 0) {
494 } else if (paddr == nextpaddr) {
497 /* Go to the next segment */
500 if (seg > dmat->nsegments)
506 nextpaddr = paddr + size;
508 } while (buflen > 0);
511 printf("bus_dmamap_load: Too many segs! buf_len = 0x%lx\n",
516 (*callback)(callback_arg, dmat->segments, seg, error);
522 * Utility function to load a linear buffer. lastaddrp holds state
523 * between invocations (for multiple-buffer loads). segp contains
524 * the starting segment on entrace, and the ending segment on exit.
525 * first indicates if this is the first invocation of this function.
528 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
529 void *buf, bus_size_t buflen,
532 vm_offset_t *lastaddrp,
536 bus_dma_segment_t *segs;
538 bus_addr_t curaddr, lastaddr, baddr, bmask;
539 vm_offset_t vaddr = (vm_offset_t)buf;
543 if (td->td_proc != NULL)
544 pmap = vmspace_pmap(td->td_proc->p_vmspace);
548 segs = dmat->segments;
549 lastaddr = *lastaddrp;
550 bmask = ~(dmat->boundary - 1);
552 for (seg = *segp; buflen > 0 ; ) {
554 * Get the physical address for this segment.
557 curaddr = pmap_extract(pmap, vaddr);
559 curaddr = pmap_kextract(vaddr);
562 * Compute the segment size, and adjust counts.
564 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK);
569 * Make sure we don't cross any boundaries.
571 if (dmat->boundary > 0) {
572 baddr = (curaddr + dmat->boundary) & bmask;
573 if (sgsize > (baddr - curaddr))
574 sgsize = (baddr - curaddr);
578 * Insert chunk into a segment, coalescing with
579 * previous segment if possible.
582 segs[seg].ds_addr = curaddr;
583 segs[seg].ds_len = sgsize;
586 if (curaddr == lastaddr &&
587 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
588 (dmat->boundary == 0 ||
589 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
590 segs[seg].ds_len += sgsize;
592 if (++seg >= dmat->nsegments)
594 segs[seg].ds_addr = curaddr;
595 segs[seg].ds_len = sgsize;
599 lastaddr = curaddr + sgsize;
605 *lastaddrp = lastaddr;
610 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
614 * Like _bus_dmamap_load(), but for mbufs.
617 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
619 bus_dmamap_callback2_t *callback, void *callback_arg,
624 KASSERT(dmat->lowaddr >= ptoa(Maxmem) || map != NULL,
625 ("bus_dmamap_load_mbuf: No support for bounce pages!"));
626 KASSERT(m0->m_flags & M_PKTHDR,
627 ("bus_dmamap_load_mbuf: no packet header"));
631 if (m0->m_pkthdr.len <= dmat->maxsize) {
633 vm_offset_t lastaddr = 0;
636 for (m = m0; m != NULL && error == 0; m = m->m_next) {
639 error = _bus_dmamap_load_buffer(dmat,
641 curthread, flags, &lastaddr,
650 /* force "no valid mappings" in callback */
651 (*callback)(callback_arg, dmat->segments, 0, 0, error);
653 (*callback)(callback_arg, dmat->segments,
654 nsegs+1, m0->m_pkthdr.len, error);
660 * Like _bus_dmamap_load(), but for uios.
663 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
665 bus_dmamap_callback2_t *callback, void *callback_arg,
668 vm_offset_t lastaddr;
669 int nsegs, error, first, i;
672 struct thread *td = NULL;
674 KASSERT(dmat->lowaddr >= ptoa(Maxmem) || map != NULL,
675 ("bus_dmamap_load_uio: No support for bounce pages!"));
677 resid = uio->uio_resid;
680 if (uio->uio_segflg == UIO_USERSPACE) {
682 KASSERT(td != NULL && td->td_proc != NULL,
683 ("bus_dmamap_load_uio: USERSPACE but no proc"));
689 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
691 * Now at the first iovec to load. Load each iovec
692 * until we have exhausted the residual count.
695 resid < iov[i].iov_len ? resid : iov[i].iov_len;
696 caddr_t addr = (caddr_t) iov[i].iov_base;
698 error = _bus_dmamap_load_buffer(dmat,
700 td, flags, &lastaddr, &nsegs, first);
707 /* force "no valid mappings" in callback */
708 (*callback)(callback_arg, dmat->segments, 0, 0, error);
710 (*callback)(callback_arg, dmat->segments,
711 nsegs+1, uio->uio_resid, error);
717 * Release the mapping held by map.
720 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
722 struct bounce_page *bpage;
724 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
725 STAILQ_REMOVE_HEAD(&map->bpages, links);
726 free_bounce_page(dmat, bpage);
731 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
733 struct bounce_page *bpage;
735 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
738 * Handle data bouncing. We might also
739 * want to add support for invalidating
740 * the caches on broken hardware
743 case BUS_DMASYNC_PREWRITE:
744 while (bpage != NULL) {
745 bcopy((void *)bpage->datavaddr,
746 (void *)bpage->vaddr,
748 bpage = STAILQ_NEXT(bpage, links);
752 case BUS_DMASYNC_POSTREAD:
753 while (bpage != NULL) {
754 bcopy((void *)bpage->vaddr,
755 (void *)bpage->datavaddr,
757 bpage = STAILQ_NEXT(bpage, links);
760 case BUS_DMASYNC_PREREAD:
761 case BUS_DMASYNC_POSTWRITE:
769 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
774 if (total_bpages == 0) {
775 STAILQ_INIT(&bounce_page_list);
776 STAILQ_INIT(&bounce_map_waitinglist);
777 STAILQ_INIT(&bounce_map_callbacklist);
780 while (numpages > 0) {
781 struct bounce_page *bpage;
783 bpage = (struct bounce_page *)kmalloc(sizeof(*bpage), M_DEVBUF,
788 bzero(bpage, sizeof(*bpage));
789 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
794 if (bpage->vaddr == NULL) {
795 kfree(bpage, M_DEVBUF);
798 bpage->busaddr = pmap_kextract(bpage->vaddr);
800 STAILQ_INSERT_TAIL(&bounce_page_list, bpage, links);
811 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map)
815 pages = MIN(free_bpages, map->pagesneeded - map->pagesreserved);
816 free_bpages -= pages;
817 reserved_bpages += pages;
818 map->pagesreserved += pages;
819 pages = map->pagesneeded - map->pagesreserved;
825 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
828 struct bounce_page *bpage;
830 if (map->pagesneeded == 0)
831 panic("add_bounce_page: map doesn't need any pages");
834 if (map->pagesreserved == 0)
835 panic("add_bounce_page: map doesn't need any pages");
836 map->pagesreserved--;
839 bpage = STAILQ_FIRST(&bounce_page_list);
841 panic("add_bounce_page: free page list is empty");
843 STAILQ_REMOVE_HEAD(&bounce_page_list, links);
848 bpage->datavaddr = vaddr;
849 bpage->datacount = size;
850 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
851 return (bpage->busaddr);
855 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
857 struct bus_dmamap *map;
859 bpage->datavaddr = 0;
860 bpage->datacount = 0;
863 STAILQ_INSERT_HEAD(&bounce_page_list, bpage, links);
866 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
867 if (reserve_bounce_pages(map->dmat, map) == 0) {
868 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
869 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
871 busdma_swi_pending = 1;
881 struct bus_dmamap *map;
884 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
885 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
887 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
888 map->callback, map->callback_arg, /*flags*/0);