2 * Copyright (c) 2012 Ian Lepore
3 * Copyright (c) 2004 Olivier Houchard
4 * Copyright (c) 2002 Peter Grehan
5 * Copyright (c) 1997, 1998 Justin T. Gibbs.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions, and the following disclaimer,
13 * without modification, immediately at the beginning of the file.
14 * 2. The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
21 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * From i386/busdma_machdep.c,v 1.26 2002/04/19 22:58:09 alfred
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
36 * ARM bus dma support routines.
38 * XXX Things to investigate / fix some day...
39 * - What is the earliest that this API can be called? Could there be any
40 * fallout from changing the SYSINIT() order from SI_SUB_VM to SI_SUB_KMEM?
41 * - The manpage mentions the BUS_DMA_NOWAIT flag only in the context of the
42 * bus_dmamap_load() function. This code has historically (and still does)
43 * honor it in bus_dmamem_alloc(). If we got rid of that we could lose some
44 * error checking because some resource management calls would become WAITOK
45 * and thus "cannot fail."
46 * - The decisions made by _bus_dma_can_bounce() should be made once, at tag
47 * creation time, and the result stored in the tag.
48 * - It should be possible to take some shortcuts when mapping a buffer we know
49 * came from the uma(9) allocators based on what we know about such buffers
50 * (aligned, contiguous, etc).
51 * - The allocation of bounce pages could probably be cleaned up, then we could
52 * retire arm_remap_nocache().
55 #define _ARM32_BUS_DMA_PRIVATE
56 #include <sys/param.h>
57 #include <sys/systm.h>
58 #include <sys/malloc.h>
60 #include <sys/busdma_bufalloc.h>
61 #include <sys/counter.h>
62 #include <sys/interrupt.h>
63 #include <sys/kernel.h>
66 #include <sys/memdesc.h>
68 #include <sys/mutex.h>
69 #include <sys/sysctl.h>
73 #include <vm/vm_param.h>
74 #include <vm/vm_page.h>
75 #include <vm/vm_phys.h>
76 #include <vm/vm_map.h>
77 #include <vm/vm_extern.h>
78 #include <vm/vm_kern.h>
80 #include <machine/atomic.h>
81 #include <machine/bus.h>
82 #include <machine/cpufunc.h>
83 #include <machine/md_var.h>
86 #define MAX_DMA_SEGMENTS 4096
87 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
88 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
98 bus_dma_filter_t *filter;
106 bus_dma_lock_t *lockfunc;
108 struct bounce_zone *bounce_zone;
110 * DMA range for this tag. If the page doesn't fall within
111 * one of these ranges, an error is returned. The caller
112 * may then decide what to do with the transfer. If the
113 * range pointer is NULL, it is ignored.
115 struct arm32_dma_range *ranges;
120 vm_offset_t vaddr; /* kva of bounce buffer */
121 bus_addr_t busaddr; /* Physical address */
122 vm_offset_t datavaddr; /* kva of client data */
123 vm_page_t datapage; /* physical page of client data */
124 vm_offset_t dataoffs; /* page offset of client data */
125 bus_size_t datacount; /* client data count */
126 STAILQ_ENTRY(bounce_page) links;
130 vm_offset_t vaddr; /* kva of client data */
131 vm_page_t pages; /* starting page of client data */
132 vm_offset_t dataoffs; /* page offset of client data */
133 bus_size_t datacount; /* client data count */
136 int busdma_swi_pending;
139 STAILQ_ENTRY(bounce_zone) links;
140 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
148 bus_size_t alignment;
152 struct sysctl_ctx_list sysctl_tree;
153 struct sysctl_oid *sysctl_tree_top;
156 static struct mtx bounce_lock;
157 static int total_bpages;
158 static int busdma_zonecount;
159 static uint32_t tags_total;
160 static uint32_t maps_total;
161 static uint32_t maps_dmamem;
162 static uint32_t maps_coherent;
163 static counter_u64_t maploads_total;
164 static counter_u64_t maploads_bounced;
165 static counter_u64_t maploads_coherent;
166 static counter_u64_t maploads_dmamem;
167 static counter_u64_t maploads_mbuf;
168 static counter_u64_t maploads_physmem;
170 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
172 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
173 SYSCTL_UINT(_hw_busdma, OID_AUTO, tags_total, CTLFLAG_RD, &tags_total, 0,
174 "Number of active tags");
175 SYSCTL_UINT(_hw_busdma, OID_AUTO, maps_total, CTLFLAG_RD, &maps_total, 0,
176 "Number of active maps");
177 SYSCTL_UINT(_hw_busdma, OID_AUTO, maps_dmamem, CTLFLAG_RD, &maps_dmamem, 0,
178 "Number of active maps for bus_dmamem_alloc buffers");
179 SYSCTL_UINT(_hw_busdma, OID_AUTO, maps_coherent, CTLFLAG_RD, &maps_coherent, 0,
180 "Number of active maps with BUS_DMA_COHERENT flag set");
181 SYSCTL_COUNTER_U64(_hw_busdma, OID_AUTO, maploads_total, CTLFLAG_RD,
182 &maploads_total, "Number of load operations performed");
183 SYSCTL_COUNTER_U64(_hw_busdma, OID_AUTO, maploads_bounced, CTLFLAG_RD,
184 &maploads_bounced, "Number of load operations that used bounce buffers");
185 SYSCTL_COUNTER_U64(_hw_busdma, OID_AUTO, maploads_coherent, CTLFLAG_RD,
186 &maploads_dmamem, "Number of load operations on BUS_DMA_COHERENT memory");
187 SYSCTL_COUNTER_U64(_hw_busdma, OID_AUTO, maploads_dmamem, CTLFLAG_RD,
188 &maploads_dmamem, "Number of load operations on bus_dmamem_alloc buffers");
189 SYSCTL_COUNTER_U64(_hw_busdma, OID_AUTO, maploads_mbuf, CTLFLAG_RD,
190 &maploads_mbuf, "Number of load operations for mbufs");
191 SYSCTL_COUNTER_U64(_hw_busdma, OID_AUTO, maploads_physmem, CTLFLAG_RD,
192 &maploads_physmem, "Number of load operations on physical buffers");
193 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
194 "Total bounce pages");
197 struct bp_list bpages;
202 bus_dmamap_callback_t *callback;
205 #define DMAMAP_COHERENT (1 << 0)
206 #define DMAMAP_DMAMEM_ALLOC (1 << 1)
207 #define DMAMAP_MBUF (1 << 2)
208 #define DMAMAP_CACHE_ALIGNED (1 << 3)
209 STAILQ_ENTRY(bus_dmamap) links;
210 bus_dma_segment_t *segments;
212 struct sync_list slist[];
215 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
216 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
218 static void init_bounce_pages(void *dummy);
219 static int alloc_bounce_zone(bus_dma_tag_t dmat);
220 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
221 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
223 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
224 vm_offset_t vaddr, bus_addr_t addr, bus_size_t size);
225 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
226 static void bus_dmamap_sync_sl(struct sync_list *sl, bus_dmasync_op_t op,
230 * ----------------------------------------------------------------------------
231 * Begin block of code useful to transplant to other implementations.
234 static busdma_bufalloc_t coherent_allocator; /* Cache of coherent buffers */
235 static busdma_bufalloc_t standard_allocator; /* Cache of standard buffers */
237 MALLOC_DEFINE(M_BUSDMA, "busdma", "busdma metadata");
238 MALLOC_DEFINE(M_BOUNCE, "bounce", "busdma bounce pages");
241 busdma_init(void *dummy)
244 maploads_total = counter_u64_alloc(M_WAITOK);
245 maploads_bounced = counter_u64_alloc(M_WAITOK);
246 maploads_coherent = counter_u64_alloc(M_WAITOK);
247 maploads_dmamem = counter_u64_alloc(M_WAITOK);
248 maploads_mbuf = counter_u64_alloc(M_WAITOK);
249 maploads_physmem = counter_u64_alloc(M_WAITOK);
251 /* Create a cache of buffers in standard (cacheable) memory. */
252 standard_allocator = busdma_bufalloc_create("buffer",
253 arm_dcache_align, /* minimum_alignment */
254 NULL, /* uma_alloc func */
255 NULL, /* uma_free func */
256 0); /* uma_zcreate_flags */
259 * Create a cache of buffers in uncacheable memory, to implement the
260 * BUS_DMA_COHERENT (and potentially BUS_DMA_NOCACHE) flag.
262 coherent_allocator = busdma_bufalloc_create("coherent",
263 arm_dcache_align, /* minimum_alignment */
264 busdma_bufalloc_alloc_uncacheable,
265 busdma_bufalloc_free_uncacheable,
266 0); /* uma_zcreate_flags */
270 * This init historically used SI_SUB_VM, but now the init code requires
271 * malloc(9) using M_BUSDMA memory and the pcpu zones for counter(9), which get
272 * set up by SI_SUB_KMEM and SI_ORDER_LAST, so we'll go right after that by
273 * using SI_SUB_KMEM+1.
275 SYSINIT(busdma, SI_SUB_KMEM+1, SI_ORDER_FIRST, busdma_init, NULL);
278 * End block of code useful to transplant to other implementations.
279 * ----------------------------------------------------------------------------
283 * Return true if a match is made.
285 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'.
287 * If paddr is within the bounds of the dma tag then call the filter callback
288 * to check for a match, if there is no filter callback then assume a match.
291 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
298 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr)
299 || ((paddr & (dmat->alignment - 1)) != 0))
300 && (dmat->filter == NULL
301 || (*dmat->filter)(dmat->filterarg, paddr) != 0))
305 } while (retval == 0 && dmat != NULL);
310 * This routine checks the exclusion zone constraints from a tag against the
311 * physical RAM available on the machine. If a tag specifies an exclusion zone
312 * but there's no RAM in that zone, then we avoid allocating resources to bounce
313 * a request, and we can use any memory allocator (as opposed to needing
314 * kmem_alloc_contig() just because it can allocate pages in an address range).
316 * Most tags have BUS_SPACE_MAXADDR or BUS_SPACE_MAXADDR_32BIT (they are the
317 * same value on 32-bit architectures) as their lowaddr constraint, and we can't
318 * possibly have RAM at an address higher than the highest address we can
319 * express, so we take a fast out.
322 _bus_dma_can_bounce(vm_offset_t lowaddr, vm_offset_t highaddr)
326 if (lowaddr >= BUS_SPACE_MAXADDR)
329 for (i = 0; phys_avail[i] && phys_avail[i + 1]; i += 2) {
330 if ((lowaddr >= phys_avail[i] && lowaddr <= phys_avail[i + 1])
331 || (lowaddr < phys_avail[i] &&
332 highaddr > phys_avail[i]))
338 static __inline struct arm32_dma_range *
339 _bus_dma_inrange(struct arm32_dma_range *ranges, int nranges,
342 struct arm32_dma_range *dr;
345 for (i = 0, dr = ranges; i < nranges; i++, dr++) {
346 if (curaddr >= dr->dr_sysbase &&
347 round_page(curaddr) <= (dr->dr_sysbase + dr->dr_len))
355 * Convenience function for manipulating driver locks from busdma (during
356 * busdma_swi, for example). Drivers that don't provide their own locks
357 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own
358 * non-mutex locking scheme don't have to use this at all.
361 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
365 dmtx = (struct mtx *)arg;
374 panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
379 * dflt_lock should never get called. It gets put into the dma tag when
380 * lockfunc == NULL, which is only valid if the maps that are associated
381 * with the tag are meant to never be defered.
382 * XXX Should have a way to identify which driver is responsible here.
385 dflt_lock(void *arg, bus_dma_lock_op_t op)
388 panic("driver error: busdma dflt_lock called");
390 printf("DRIVER_ERROR: busdma dflt_lock called\n");
395 * Allocate a device specific dma_tag.
398 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
399 bus_addr_t boundary, bus_addr_t lowaddr, bus_addr_t highaddr,
400 bus_dma_filter_t *filter, void *filterarg, bus_size_t maxsize,
401 int nsegments, bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
402 void *lockfuncarg, bus_dma_tag_t *dmat)
404 bus_dma_tag_t newtag;
406 /* Return a NULL tag on failure */
409 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_BUSDMA, M_NOWAIT);
410 if (newtag == NULL) {
411 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
412 __func__, newtag, 0, error);
416 newtag->parent = parent;
417 newtag->alignment = alignment ? alignment : 1;
418 newtag->boundary = boundary;
419 newtag->lowaddr = trunc_page((vm_offset_t)lowaddr) + (PAGE_SIZE - 1);
420 newtag->highaddr = trunc_page((vm_offset_t)highaddr) + (PAGE_SIZE - 1);
421 newtag->filter = filter;
422 newtag->filterarg = filterarg;
423 newtag->maxsize = maxsize;
424 newtag->nsegments = nsegments;
425 newtag->maxsegsz = maxsegsz;
426 newtag->flags = flags;
427 newtag->ref_count = 1; /* Count ourself */
428 newtag->map_count = 0;
429 newtag->ranges = bus_dma_get_range();
430 newtag->_nranges = bus_dma_get_range_nb();
431 if (lockfunc != NULL) {
432 newtag->lockfunc = lockfunc;
433 newtag->lockfuncarg = lockfuncarg;
435 newtag->lockfunc = dflt_lock;
436 newtag->lockfuncarg = NULL;
439 /* Take into account any restrictions imposed by our parent tag */
440 if (parent != NULL) {
441 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
442 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
443 if (newtag->boundary == 0)
444 newtag->boundary = parent->boundary;
445 else if (parent->boundary != 0)
446 newtag->boundary = MIN(parent->boundary,
448 if ((newtag->filter != NULL) ||
449 ((parent->flags & BUS_DMA_COULD_BOUNCE) != 0))
450 newtag->flags |= BUS_DMA_COULD_BOUNCE;
451 if (newtag->filter == NULL) {
453 * Short circuit looking at our parent directly
454 * since we have encapsulated all of its information
456 newtag->filter = parent->filter;
457 newtag->filterarg = parent->filterarg;
458 newtag->parent = parent->parent;
460 if (newtag->parent != NULL)
461 atomic_add_int(&parent->ref_count, 1);
463 if (_bus_dma_can_bounce(newtag->lowaddr, newtag->highaddr)
464 || newtag->alignment > 1)
465 newtag->flags |= BUS_DMA_COULD_BOUNCE;
467 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
468 (flags & BUS_DMA_ALLOCNOW) != 0) {
469 struct bounce_zone *bz;
473 if ((error = alloc_bounce_zone(newtag)) != 0) {
474 free(newtag, M_BUSDMA);
477 bz = newtag->bounce_zone;
479 if (ptoa(bz->total_bpages) < maxsize) {
482 pages = atop(maxsize) - bz->total_bpages;
484 /* Add pages to our bounce pool */
485 if (alloc_bounce_pages(newtag, pages) < pages)
488 /* Performed initial allocation */
489 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
491 newtag->bounce_zone = NULL;
494 free(newtag, M_BUSDMA);
496 atomic_add_32(&tags_total, 1);
499 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
500 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
505 bus_dma_tag_set_domain(bus_dma_tag_t dmat, int domain)
512 bus_dma_tag_destroy(bus_dma_tag_t dmat)
514 bus_dma_tag_t dmat_copy;
522 if (dmat->map_count != 0) {
527 while (dmat != NULL) {
528 bus_dma_tag_t parent;
530 parent = dmat->parent;
531 atomic_subtract_int(&dmat->ref_count, 1);
532 if (dmat->ref_count == 0) {
533 atomic_subtract_32(&tags_total, 1);
534 free(dmat, M_BUSDMA);
536 * Last reference count, so
537 * release our reference
538 * count on our parent.
546 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
551 allocate_bz_and_pages(bus_dma_tag_t dmat, bus_dmamap_t map)
556 * Bouncing might be required if the driver asks for an active
557 * exclusion region, a data alignment that is stricter than 1, and/or
558 * an active address boundary.
560 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
563 struct bounce_zone *bz;
566 if (dmat->bounce_zone == NULL) {
567 if ((error = alloc_bounce_zone(dmat)) != 0) {
571 bz = dmat->bounce_zone;
573 /* Initialize the new map */
574 STAILQ_INIT(&(map->bpages));
577 * Attempt to add pages to our pool on a per-instance
578 * basis up to a sane limit.
580 maxpages = MAX_BPAGES;
581 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
582 || (bz->map_count > 0 && bz->total_bpages < maxpages)) {
585 pages = MAX(atop(dmat->maxsize), 1);
586 pages = MIN(maxpages - bz->total_bpages, pages);
587 pages = MAX(pages, 1);
588 if (alloc_bounce_pages(dmat, pages) < pages)
591 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0)
592 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
600 allocate_map(bus_dma_tag_t dmat, int mflags)
602 int mapsize, segsize;
606 * Allocate the map. The map structure ends with an embedded
607 * variable-sized array of sync_list structures. Following that
608 * we allocate enough extra space to hold the array of bus_dma_segments.
610 KASSERT(dmat->nsegments <= MAX_DMA_SEGMENTS,
611 ("cannot allocate %u dma segments (max is %u)",
612 dmat->nsegments, MAX_DMA_SEGMENTS));
613 segsize = sizeof(struct bus_dma_segment) * dmat->nsegments;
614 mapsize = sizeof(*map) + sizeof(struct sync_list) * dmat->nsegments;
615 map = malloc(mapsize + segsize, M_BUSDMA, mflags | M_ZERO);
617 CTR3(KTR_BUSDMA, "%s: tag %p error %d", __func__, dmat, ENOMEM);
620 map->segments = (bus_dma_segment_t *)((uintptr_t)map + mapsize);
625 * Allocate a handle for mapping from kva/uva/physical
626 * address space into bus device space.
629 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
634 *mapp = map = allocate_map(dmat, M_NOWAIT);
636 CTR3(KTR_BUSDMA, "%s: tag %p error %d", __func__, dmat, ENOMEM);
641 * Bouncing might be required if the driver asks for an exclusion
642 * region, a data alignment that is stricter than 1, or DMA that begins
643 * or ends with a partial cacheline. Whether bouncing will actually
644 * happen can't be known until mapping time, but we need to pre-allocate
645 * resources now because we might not be allowed to at mapping time.
647 error = allocate_bz_and_pages(dmat, map);
653 if (map->flags & DMAMAP_COHERENT)
654 atomic_add_32(&maps_coherent, 1);
655 atomic_add_32(&maps_total, 1);
662 * Destroy a handle for mapping from kva/uva/physical
663 * address space into bus device space.
666 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
669 if (STAILQ_FIRST(&map->bpages) != NULL || map->sync_count != 0) {
670 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
671 __func__, dmat, EBUSY);
674 if (dmat->bounce_zone)
675 dmat->bounce_zone->map_count--;
676 if (map->flags & DMAMAP_COHERENT)
677 atomic_subtract_32(&maps_coherent, 1);
678 atomic_subtract_32(&maps_total, 1);
681 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
686 * Allocate a piece of memory that can be efficiently mapped into bus device
687 * space based on the constraints listed in the dma tag. Returns a pointer to
688 * the allocated memory, and a pointer to an associated bus_dmamap.
691 bus_dmamem_alloc(bus_dma_tag_t dmat, void **vaddr, int flags,
694 busdma_bufalloc_t ba;
695 struct busdma_bufzone *bufzone;
697 vm_memattr_t memattr;
700 if (flags & BUS_DMA_NOWAIT)
704 if (flags & BUS_DMA_ZERO)
707 *mapp = map = allocate_map(dmat, mflags);
709 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
710 __func__, dmat, dmat->flags, ENOMEM);
713 map->flags = DMAMAP_DMAMEM_ALLOC;
715 /* Choose a busdma buffer allocator based on memory type flags. */
716 if (flags & BUS_DMA_COHERENT) {
717 memattr = VM_MEMATTR_UNCACHEABLE;
718 ba = coherent_allocator;
719 map->flags |= DMAMAP_COHERENT;
721 memattr = VM_MEMATTR_DEFAULT;
722 ba = standard_allocator;
726 * Try to find a bufzone in the allocator that holds a cache of buffers
727 * of the right size for this request. If the buffer is too big to be
728 * held in the allocator cache, this returns NULL.
730 bufzone = busdma_bufalloc_findzone(ba, dmat->maxsize);
733 * Allocate the buffer from the uma(9) allocator if...
734 * - It's small enough to be in the allocator (bufzone not NULL).
735 * - The alignment constraint isn't larger than the allocation size
736 * (the allocator aligns buffers to their size boundaries).
737 * - There's no need to handle lowaddr/highaddr exclusion zones.
738 * else allocate non-contiguous pages if...
739 * - The page count that could get allocated doesn't exceed nsegments.
740 * - The alignment constraint isn't larger than a page boundary.
741 * - There are no boundary-crossing constraints.
742 * else allocate a block of contiguous pages because one or more of the
743 * constraints is something that only the contig allocator can fulfill.
745 if (bufzone != NULL && dmat->alignment <= bufzone->size &&
746 !_bus_dma_can_bounce(dmat->lowaddr, dmat->highaddr)) {
747 *vaddr = uma_zalloc(bufzone->umazone, mflags);
748 } else if (dmat->nsegments >=
749 howmany(dmat->maxsize, MIN(dmat->maxsegsz, PAGE_SIZE)) &&
750 dmat->alignment <= PAGE_SIZE &&
751 (dmat->boundary % PAGE_SIZE) == 0) {
752 *vaddr = (void *)kmem_alloc_attr(dmat->maxsize, mflags, 0,
753 dmat->lowaddr, memattr);
755 *vaddr = (void *)kmem_alloc_contig(dmat->maxsize, mflags, 0,
756 dmat->lowaddr, dmat->alignment, dmat->boundary, memattr);
758 if (*vaddr == NULL) {
759 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
760 __func__, dmat, dmat->flags, ENOMEM);
765 if (map->flags & DMAMAP_COHERENT)
766 atomic_add_32(&maps_coherent, 1);
767 atomic_add_32(&maps_dmamem, 1);
768 atomic_add_32(&maps_total, 1);
771 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
772 __func__, dmat, dmat->flags, 0);
777 * Free a piece of memory that was allocated via bus_dmamem_alloc, along with
778 * its associated map.
781 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
783 struct busdma_bufzone *bufzone;
784 busdma_bufalloc_t ba;
786 if (map->flags & DMAMAP_COHERENT)
787 ba = coherent_allocator;
789 ba = standard_allocator;
791 bufzone = busdma_bufalloc_findzone(ba, dmat->maxsize);
793 if (bufzone != NULL && dmat->alignment <= bufzone->size &&
794 !_bus_dma_can_bounce(dmat->lowaddr, dmat->highaddr))
795 uma_zfree(bufzone->umazone, vaddr);
797 kmem_free((vm_offset_t)vaddr, dmat->maxsize);
800 if (map->flags & DMAMAP_COHERENT)
801 atomic_subtract_32(&maps_coherent, 1);
802 atomic_subtract_32(&maps_total, 1);
803 atomic_subtract_32(&maps_dmamem, 1);
805 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
809 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf,
810 bus_size_t buflen, int flags)
815 if (map->pagesneeded == 0) {
816 CTR3(KTR_BUSDMA, "lowaddr= %d, boundary= %d, alignment= %d",
817 dmat->lowaddr, dmat->boundary, dmat->alignment);
818 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d",
819 map, map->pagesneeded);
821 * Count the number of bounce pages
822 * needed in order to complete this transfer
825 while (buflen != 0) {
826 sgsize = MIN(buflen, dmat->maxsegsz);
827 if (run_filter(dmat, curaddr) != 0) {
829 PAGE_SIZE - (curaddr & PAGE_MASK));
835 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
840 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap,
841 void *buf, bus_size_t buflen, int flags)
844 vm_offset_t vendaddr;
847 if (map->pagesneeded == 0) {
848 CTR3(KTR_BUSDMA, "lowaddr= %d, boundary= %d, alignment= %d",
849 dmat->lowaddr, dmat->boundary, dmat->alignment);
850 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d",
851 map, map->pagesneeded);
853 * Count the number of bounce pages
854 * needed in order to complete this transfer
856 vaddr = trunc_page((vm_offset_t)buf);
857 vendaddr = (vm_offset_t)buf + buflen;
859 while (vaddr < vendaddr) {
860 if (__predict_true(pmap == kernel_pmap))
861 paddr = pmap_kextract(vaddr);
863 paddr = pmap_extract(pmap, vaddr);
864 if (run_filter(dmat, paddr) != 0)
868 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
873 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags)
876 /* Reserve Necessary Bounce Pages */
877 mtx_lock(&bounce_lock);
878 if (flags & BUS_DMA_NOWAIT) {
879 if (reserve_bounce_pages(dmat, map, 0) != 0) {
880 mtx_unlock(&bounce_lock);
884 if (reserve_bounce_pages(dmat, map, 1) != 0) {
885 /* Queue us for resources */
886 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, map, links);
887 mtx_unlock(&bounce_lock);
888 return (EINPROGRESS);
891 mtx_unlock(&bounce_lock);
897 * Add a single contiguous physical range to the segment list.
900 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, bus_addr_t curaddr,
901 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp)
903 bus_addr_t baddr, bmask;
907 * Make sure we don't cross any boundaries.
909 bmask = ~(dmat->boundary - 1);
910 if (dmat->boundary > 0) {
911 baddr = (curaddr + dmat->boundary) & bmask;
912 if (sgsize > (baddr - curaddr))
913 sgsize = (baddr - curaddr);
916 struct arm32_dma_range *dr;
918 dr = _bus_dma_inrange(dmat->ranges, dmat->_nranges,
923 * In a valid DMA range. Translate the physical
924 * memory address to an address in the DMA window.
926 curaddr = (curaddr - dr->dr_sysbase) + dr->dr_busbase;
932 * Insert chunk into a segment, coalescing with
933 * the previous segment if possible.
936 curaddr == segs[seg].ds_addr + segs[seg].ds_len &&
937 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
938 (dmat->boundary == 0 ||
939 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) {
940 segs[seg].ds_len += sgsize;
942 if (++seg >= dmat->nsegments)
944 segs[seg].ds_addr = curaddr;
945 segs[seg].ds_len = sgsize;
952 * Utility function to load a physical buffer. segp contains
953 * the starting segment on entrace, and the ending segment on exit.
956 _bus_dmamap_load_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf,
957 bus_size_t buflen, int flags, bus_dma_segment_t *segs, int *segp)
960 bus_addr_t sl_end = 0;
962 struct sync_list *sl;
966 segs = map->segments;
968 counter_u64_add(maploads_total, 1);
969 counter_u64_add(maploads_physmem, 1);
971 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
972 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags);
973 if (map->pagesneeded != 0) {
974 counter_u64_add(maploads_bounced, 1);
975 error = _bus_dmamap_reserve_pages(dmat, map, flags);
981 sl = map->slist + map->sync_count - 1;
985 sgsize = MIN(buflen, dmat->maxsegsz);
986 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
987 map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
988 sgsize = MIN(sgsize, PAGE_SIZE - (curaddr & PAGE_MASK));
989 curaddr = add_bounce_page(dmat, map, 0, curaddr,
992 if (map->sync_count > 0)
993 sl_end = VM_PAGE_TO_PHYS(sl->pages) +
994 sl->dataoffs + sl->datacount;
996 if (map->sync_count == 0 || curaddr != sl_end) {
997 if (++map->sync_count > dmat->nsegments)
1001 sl->datacount = sgsize;
1002 sl->pages = PHYS_TO_VM_PAGE(curaddr);
1003 sl->dataoffs = curaddr & PAGE_MASK;
1005 sl->datacount += sgsize;
1007 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
1019 bus_dmamap_unload(dmat, map);
1020 return (EFBIG); /* XXX better return value here? */
1026 _bus_dmamap_load_ma(bus_dma_tag_t dmat, bus_dmamap_t map,
1027 struct vm_page **ma, bus_size_t tlen, int ma_offs, int flags,
1028 bus_dma_segment_t *segs, int *segp)
1031 return (bus_dmamap_load_ma_triv(dmat, map, ma, tlen, ma_offs, flags,
1036 * Utility function to load a linear buffer. segp contains
1037 * the starting segment on entrance, and the ending segment on exit.
1040 _bus_dmamap_load_buffer(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
1041 bus_size_t buflen, struct pmap *pmap, int flags, bus_dma_segment_t *segs,
1046 bus_addr_t sl_pend = 0;
1047 struct sync_list *sl;
1049 vm_offset_t vaddr = (vm_offset_t)buf;
1050 vm_offset_t sl_vend = 0;
1053 counter_u64_add(maploads_total, 1);
1054 if (map->flags & DMAMAP_COHERENT)
1055 counter_u64_add(maploads_coherent, 1);
1056 if (map->flags & DMAMAP_DMAMEM_ALLOC)
1057 counter_u64_add(maploads_dmamem, 1);
1060 segs = map->segments;
1061 if (flags & BUS_DMA_LOAD_MBUF) {
1062 counter_u64_add(maploads_mbuf, 1);
1063 map->flags |= DMAMAP_CACHE_ALIGNED;
1066 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
1067 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags);
1068 if (map->pagesneeded != 0) {
1069 counter_u64_add(maploads_bounced, 1);
1070 error = _bus_dmamap_reserve_pages(dmat, map, flags);
1075 CTR3(KTR_BUSDMA, "lowaddr= %d boundary= %d, "
1076 "alignment= %d", dmat->lowaddr, dmat->boundary, dmat->alignment);
1078 sl = map->slist + map->sync_count - 1;
1080 while (buflen > 0) {
1082 * Get the physical address for this segment.
1084 if (__predict_true(pmap == kernel_pmap)) {
1085 curaddr = pmap_kextract(vaddr);
1088 curaddr = pmap_extract(pmap, vaddr);
1089 map->flags &= ~DMAMAP_COHERENT;
1094 * Compute the segment size, and adjust counts.
1096 sgsize = PAGE_SIZE - (curaddr & PAGE_MASK);
1097 if (sgsize > dmat->maxsegsz)
1098 sgsize = dmat->maxsegsz;
1099 if (buflen < sgsize)
1102 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
1103 map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
1104 curaddr = add_bounce_page(dmat, map, kvaddr, curaddr,
1107 if (map->sync_count > 0) {
1108 sl_pend = VM_PAGE_TO_PHYS(sl->pages) +
1109 sl->dataoffs + sl->datacount;
1110 sl_vend = sl->vaddr + sl->datacount;
1113 if (map->sync_count == 0 ||
1114 (kvaddr != 0 && kvaddr != sl_vend) ||
1115 (kvaddr == 0 && curaddr != sl_pend)) {
1117 if (++map->sync_count > dmat->nsegments)
1121 sl->datacount = sgsize;
1122 sl->pages = PHYS_TO_VM_PAGE(curaddr);
1123 sl->dataoffs = curaddr & PAGE_MASK;
1125 sl->datacount += sgsize;
1127 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
1140 bus_dmamap_unload(dmat, map);
1141 return (EFBIG); /* XXX better return value here? */
1147 _bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map, struct memdesc *mem,
1148 bus_dmamap_callback_t *callback, void *callback_arg)
1151 KASSERT(dmat != NULL, ("dmatag is NULL"));
1152 KASSERT(map != NULL, ("dmamap is NULL"));
1154 map->callback = callback;
1155 map->callback_arg = callback_arg;
1159 _bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map,
1160 bus_dma_segment_t *segs, int nsegs, int error)
1164 segs = map->segments;
1169 * Release the mapping held by map.
1172 bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
1174 struct bounce_page *bpage;
1175 struct bounce_zone *bz;
1177 if ((bz = dmat->bounce_zone) != NULL) {
1178 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
1179 STAILQ_REMOVE_HEAD(&map->bpages, links);
1180 free_bounce_page(dmat, bpage);
1183 bz = dmat->bounce_zone;
1184 bz->free_bpages += map->pagesreserved;
1185 bz->reserved_bpages -= map->pagesreserved;
1186 map->pagesreserved = 0;
1187 map->pagesneeded = 0;
1189 map->sync_count = 0;
1190 map->flags &= ~DMAMAP_MBUF;
1194 bus_dmamap_sync_buf(vm_offset_t buf, int len, bus_dmasync_op_t op,
1197 char _tmp_cl[arm_dcache_align], _tmp_clend[arm_dcache_align];
1201 if ((op & BUS_DMASYNC_PREWRITE) && !(op & BUS_DMASYNC_PREREAD)) {
1202 cpu_dcache_wb_range(buf, len);
1203 cpu_l2cache_wb_range(buf, len);
1207 * If the caller promises the buffer is properly aligned to a cache line
1208 * (even if the call parms make it look like it isn't) we can avoid
1209 * attempting to preserve the non-DMA part of the cache line in the
1210 * POSTREAD case, but we MUST still do a writeback in the PREREAD case.
1212 * This covers the case of mbufs, where we know how they're aligned and
1213 * know the CPU doesn't touch the header in front of the DMA data area
1214 * during the IO, but it may have touched it right before invoking the
1215 * sync, so a PREREAD writeback is required.
1217 * It also handles buffers we created in bus_dmamem_alloc(), which are
1218 * always aligned and padded to cache line size even if the IO length
1219 * isn't a multiple of cache line size. In this case the PREREAD
1220 * writeback probably isn't required, but it's harmless.
1222 partial = (((vm_offset_t)buf) | len) & arm_dcache_align_mask;
1224 if (op & BUS_DMASYNC_PREREAD) {
1225 if (!(op & BUS_DMASYNC_PREWRITE) && !partial) {
1226 cpu_dcache_inv_range(buf, len);
1227 cpu_l2cache_inv_range(buf, len);
1229 cpu_dcache_wbinv_range(buf, len);
1230 cpu_l2cache_wbinv_range(buf, len);
1233 if (op & BUS_DMASYNC_POSTREAD) {
1234 if (partial && !bufaligned) {
1236 if (buf & arm_dcache_align_mask)
1237 memcpy(_tmp_cl, (void *)(buf &
1238 ~arm_dcache_align_mask),
1239 buf & arm_dcache_align_mask);
1240 if ((buf + len) & arm_dcache_align_mask)
1242 (void *)(buf + len),
1244 ((buf + len) & arm_dcache_align_mask));
1246 cpu_dcache_inv_range(buf, len);
1247 cpu_l2cache_inv_range(buf, len);
1248 if (partial && !bufaligned) {
1249 if (buf & arm_dcache_align_mask)
1250 memcpy((void *)(buf &
1251 ~arm_dcache_align_mask), _tmp_cl,
1252 buf & arm_dcache_align_mask);
1253 if ((buf + len) & arm_dcache_align_mask)
1254 memcpy((void *)(buf + len),
1255 _tmp_clend, arm_dcache_align -
1256 ((buf + len) & arm_dcache_align_mask));
1263 bus_dmamap_sync_sl(struct sync_list *sl, bus_dmasync_op_t op,
1266 vm_offset_t tempvaddr;
1270 if (sl->vaddr != 0) {
1271 bus_dmamap_sync_buf(sl->vaddr, sl->datacount, op, bufaligned);
1276 npages = atop(round_page(sl->dataoffs + sl->datacount));
1278 for (curpage = sl->pages; curpage != sl->pages + npages; ++curpage) {
1280 * If the page is mapped to some other VA that hasn't
1281 * been supplied to busdma, then pmap_quick_enter_page()
1282 * will find all duplicate mappings and mark them
1284 * That will also do any necessary wb/inv. Otherwise,
1285 * if the page is truly unmapped, then we don't actually
1286 * need to do cache maintenance.
1287 * XXX: May overwrite DMA'ed data in the POSTREAD
1288 * case where the CPU has written to a cacheline not
1289 * completely covered by the DMA region.
1291 KASSERT(VM_PAGE_TO_PHYS(curpage) == VM_PAGE_TO_PHYS(sl->pages) +
1292 ptoa(curpage - sl->pages),
1293 ("unexpected vm_page_t phys: 0x%08x != 0x%08x",
1294 VM_PAGE_TO_PHYS(curpage), VM_PAGE_TO_PHYS(sl->pages) +
1295 ptoa(curpage - sl->pages)));
1296 tempvaddr = pmap_quick_enter_page(curpage);
1297 pmap_quick_remove_page(tempvaddr);
1302 _bus_dmamap_sync_bp(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
1304 struct bounce_page *bpage;
1305 vm_offset_t datavaddr, tempvaddr;
1307 if ((op & (BUS_DMASYNC_PREWRITE | BUS_DMASYNC_POSTREAD)) == 0)
1310 STAILQ_FOREACH(bpage, &map->bpages, links) {
1312 datavaddr = bpage->datavaddr;
1313 if (op & BUS_DMASYNC_PREWRITE) {
1314 if (datavaddr == 0) {
1316 pmap_quick_enter_page(bpage->datapage);
1317 datavaddr = tempvaddr | bpage->dataoffs;
1319 bcopy((void *)datavaddr,
1320 (void *)bpage->vaddr, bpage->datacount);
1322 pmap_quick_remove_page(tempvaddr);
1323 cpu_dcache_wb_range(bpage->vaddr, bpage->datacount);
1324 cpu_l2cache_wb_range(bpage->vaddr, bpage->datacount);
1325 dmat->bounce_zone->total_bounced++;
1327 if (op & BUS_DMASYNC_POSTREAD) {
1328 cpu_dcache_inv_range(bpage->vaddr, bpage->datacount);
1329 cpu_l2cache_inv_range(bpage->vaddr, bpage->datacount);
1330 if (datavaddr == 0) {
1332 pmap_quick_enter_page(bpage->datapage);
1333 datavaddr = tempvaddr | bpage->dataoffs;
1335 bcopy((void *)bpage->vaddr,
1336 (void *)datavaddr, bpage->datacount);
1338 pmap_quick_remove_page(tempvaddr);
1339 dmat->bounce_zone->total_bounced++;
1345 bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
1347 struct sync_list *sl, *end;
1350 if (op == BUS_DMASYNC_POSTWRITE)
1352 if (map->flags & DMAMAP_COHERENT)
1354 if (STAILQ_FIRST(&map->bpages))
1355 _bus_dmamap_sync_bp(dmat, map, op);
1356 CTR3(KTR_BUSDMA, "%s: op %x flags %x", __func__, op, map->flags);
1357 bufaligned = (map->flags & DMAMAP_CACHE_ALIGNED);
1358 if (map->sync_count) {
1359 end = &map->slist[map->sync_count];
1360 for (sl = &map->slist[0]; sl != end; sl++)
1361 bus_dmamap_sync_sl(sl, op, bufaligned);
1366 cpu_drain_writebuf();
1370 init_bounce_pages(void *dummy __unused)
1374 STAILQ_INIT(&bounce_zone_list);
1375 STAILQ_INIT(&bounce_map_waitinglist);
1376 STAILQ_INIT(&bounce_map_callbacklist);
1377 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
1379 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
1381 static struct sysctl_ctx_list *
1382 busdma_sysctl_tree(struct bounce_zone *bz)
1385 return (&bz->sysctl_tree);
1388 static struct sysctl_oid *
1389 busdma_sysctl_tree_top(struct bounce_zone *bz)
1392 return (bz->sysctl_tree_top);
1396 alloc_bounce_zone(bus_dma_tag_t dmat)
1398 struct bounce_zone *bz;
1400 /* Check to see if we already have a suitable zone */
1401 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
1402 if ((dmat->alignment <= bz->alignment) &&
1403 (dmat->lowaddr >= bz->lowaddr)) {
1404 dmat->bounce_zone = bz;
1409 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_BUSDMA,
1410 M_NOWAIT | M_ZERO)) == NULL)
1413 STAILQ_INIT(&bz->bounce_page_list);
1414 bz->free_bpages = 0;
1415 bz->reserved_bpages = 0;
1416 bz->active_bpages = 0;
1417 bz->lowaddr = dmat->lowaddr;
1418 bz->alignment = MAX(dmat->alignment, PAGE_SIZE);
1420 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
1422 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
1423 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
1424 dmat->bounce_zone = bz;
1426 sysctl_ctx_init(&bz->sysctl_tree);
1427 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
1428 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1430 if (bz->sysctl_tree_top == NULL) {
1431 sysctl_ctx_free(&bz->sysctl_tree);
1432 return (0); /* XXX error code? */
1435 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1436 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1437 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1438 "Total bounce pages");
1439 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1440 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1441 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1442 "Free bounce pages");
1443 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1444 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1445 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1446 "Reserved bounce pages");
1447 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1448 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1449 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1450 "Active bounce pages");
1451 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1452 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1453 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1454 "Total bounce requests (pages bounced)");
1455 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1456 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1457 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1458 "Total bounce requests that were deferred");
1459 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1460 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1461 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1462 SYSCTL_ADD_ULONG(busdma_sysctl_tree(bz),
1463 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1464 "alignment", CTLFLAG_RD, &bz->alignment, "");
1470 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1472 struct bounce_zone *bz;
1475 bz = dmat->bounce_zone;
1477 while (numpages > 0) {
1478 struct bounce_page *bpage;
1480 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_BUSDMA,
1485 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_BOUNCE,
1486 M_NOWAIT, 0ul, bz->lowaddr, PAGE_SIZE, 0);
1487 if (bpage->vaddr == 0) {
1488 free(bpage, M_BUSDMA);
1491 bpage->busaddr = pmap_kextract(bpage->vaddr);
1492 mtx_lock(&bounce_lock);
1493 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1497 mtx_unlock(&bounce_lock);
1505 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1507 struct bounce_zone *bz;
1510 mtx_assert(&bounce_lock, MA_OWNED);
1511 bz = dmat->bounce_zone;
1512 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1513 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1514 return (map->pagesneeded - (map->pagesreserved + pages));
1515 bz->free_bpages -= pages;
1516 bz->reserved_bpages += pages;
1517 map->pagesreserved += pages;
1518 pages = map->pagesneeded - map->pagesreserved;
1524 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1525 bus_addr_t addr, bus_size_t size)
1527 struct bounce_zone *bz;
1528 struct bounce_page *bpage;
1530 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1531 KASSERT(map != NULL, ("add_bounce_page: bad map %p", map));
1533 bz = dmat->bounce_zone;
1534 if (map->pagesneeded == 0)
1535 panic("add_bounce_page: map doesn't need any pages");
1538 if (map->pagesreserved == 0)
1539 panic("add_bounce_page: map doesn't need any pages");
1540 map->pagesreserved--;
1542 mtx_lock(&bounce_lock);
1543 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1545 panic("add_bounce_page: free page list is empty");
1547 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1548 bz->reserved_bpages--;
1549 bz->active_bpages++;
1550 mtx_unlock(&bounce_lock);
1552 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1553 /* Page offset needs to be preserved. */
1554 bpage->vaddr |= addr & PAGE_MASK;
1555 bpage->busaddr |= addr & PAGE_MASK;
1557 bpage->datavaddr = vaddr;
1558 bpage->datapage = PHYS_TO_VM_PAGE(addr);
1559 bpage->dataoffs = addr & PAGE_MASK;
1560 bpage->datacount = size;
1561 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1562 return (bpage->busaddr);
1566 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1568 struct bus_dmamap *map;
1569 struct bounce_zone *bz;
1571 bz = dmat->bounce_zone;
1572 bpage->datavaddr = 0;
1573 bpage->datacount = 0;
1574 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1576 * Reset the bounce page to start at offset 0. Other uses
1577 * of this bounce page may need to store a full page of
1578 * data and/or assume it starts on a page boundary.
1580 bpage->vaddr &= ~PAGE_MASK;
1581 bpage->busaddr &= ~PAGE_MASK;
1584 mtx_lock(&bounce_lock);
1585 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1587 bz->active_bpages--;
1588 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1589 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1590 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1591 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1593 busdma_swi_pending = 1;
1594 bz->total_deferred++;
1595 swi_sched(vm_ih, 0);
1598 mtx_unlock(&bounce_lock);
1605 struct bus_dmamap *map;
1607 mtx_lock(&bounce_lock);
1608 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1609 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1610 mtx_unlock(&bounce_lock);
1612 dmat->lockfunc(dmat->lockfuncarg, BUS_DMA_LOCK);
1613 bus_dmamap_load_mem(map->dmat, map, &map->mem, map->callback,
1614 map->callback_arg, BUS_DMA_WAITOK);
1615 dmat->lockfunc(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1616 mtx_lock(&bounce_lock);
1618 mtx_unlock(&bounce_lock);