1 /*-
2 * Copyright (c) 1997, 1998 Justin T. Gibbs.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
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.
13 *
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
24 * SUCH DAMAGE.
25 */
26
27 /*
28 * From amd64/busdma_machdep.c, r204214
29 */
30
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/malloc.h>
37 #include <sys/bus.h>
38 #include <sys/interrupt.h>
39 #include <sys/kernel.h>
40 #include <sys/ktr.h>
41 #include <sys/lock.h>
42 #include <sys/proc.h>
43 #include <sys/memdesc.h>
44 #include <sys/mutex.h>
45 #include <sys/sysctl.h>
46 #include <sys/uio.h>
47
48 #include <vm/vm.h>
49 #include <vm/vm_extern.h>
50 #include <vm/vm_kern.h>
51 #include <vm/vm_page.h>
52 #include <vm/vm_map.h>
53
54 #include <machine/atomic.h>
55 #include <machine/bus.h>
56 #include <machine/md_var.h>
57
58 #include "iommu_if.h"
59
60 #define MAX_BPAGES MIN(8192, physmem/40)
61
62 struct bounce_zone;
63
64 struct bus_dma_tag {
65 bus_dma_tag_t parent;
66 bus_size_t alignment;
67 bus_size_t boundary;
68 bus_addr_t lowaddr;
69 bus_addr_t highaddr;
70 bus_dma_filter_t *filter;
71 void *filterarg;
72 bus_size_t maxsize;
73 u_int nsegments;
74 bus_size_t maxsegsz;
75 int flags;
76 int ref_count;
77 int map_count;
78 bus_dma_lock_t *lockfunc;
79 void *lockfuncarg;
80 struct bounce_zone *bounce_zone;
81 device_t iommu;
82 void *iommu_cookie;
83 };
84
85 struct bounce_page {
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;
92 };
93
94 int busdma_swi_pending;
95
96 struct bounce_zone {
97 STAILQ_ENTRY(bounce_zone) links;
98 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
99 int total_bpages;
100 int free_bpages;
101 int reserved_bpages;
102 int active_bpages;
103 int total_bounced;
104 int total_deferred;
105 int map_count;
106 bus_size_t alignment;
107 bus_addr_t lowaddr;
108 char zoneid[8];
109 char lowaddrid[20];
110 struct sysctl_ctx_list sysctl_tree;
111 struct sysctl_oid *sysctl_tree_top;
112 };
113
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;
118
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");
122
123 struct bus_dmamap {
124 struct bp_list bpages;
125 int pagesneeded;
126 int pagesreserved;
127 bus_dma_tag_t dmat;
128 struct memdesc mem;
129 bus_dma_segment_t *segments;
130 int nsegs;
131 bus_dmamap_callback_t *callback;
132 void *callback_arg;
133 STAILQ_ENTRY(bus_dmamap) links;
134 int contigalloc;
135 };
136
137 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
138 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
139
140 static void init_bounce_pages(void *dummy);
141 static int alloc_bounce_zone(bus_dma_tag_t dmat);
142 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
143 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
144 int commit);
145 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
146 vm_offset_t vaddr, bus_addr_t addr,
147 bus_size_t size);
148 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
149 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
150
151 /*
152 * Return true if a match is made.
153 *
154 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'.
155 *
156 * If paddr is within the bounds of the dma tag then call the filter callback
157 * to check for a match, if there is no filter callback then assume a match.
158 */
159 static __inline int
160 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
161 {
162 int retval;
163
164 retval = 0;
165
166 do {
167 if (dmat->filter == NULL && dmat->iommu == NULL &&
168 paddr > dmat->lowaddr && paddr <= dmat->highaddr)
169 retval = 1;
170 if (dmat->filter == NULL &&
171 (paddr & (dmat->alignment - 1)) != 0)
172 retval = 1;
173 if (dmat->filter != NULL &&
174 (*dmat->filter)(dmat->filterarg, paddr) != 0)
175 retval = 1;
176
177 dmat = dmat->parent;
178 } while (retval == 0 && dmat != NULL);
179 return (retval);
180 }
181
182 /*
183 * Convenience function for manipulating driver locks from busdma (during
184 * busdma_swi, for example). Drivers that don't provide their own locks
185 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own
186 * non-mutex locking scheme don't have to use this at all.
187 */
188 void
189 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
190 {
191 struct mtx *dmtx;
192
193 dmtx = (struct mtx *)arg;
194 switch (op) {
195 case BUS_DMA_LOCK:
196 mtx_lock(dmtx);
197 break;
198 case BUS_DMA_UNLOCK:
199 mtx_unlock(dmtx);
200 break;
201 default:
202 panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
203 }
204 }
205
206 /*
207 * dflt_lock should never get called. It gets put into the dma tag when
208 * lockfunc == NULL, which is only valid if the maps that are associated
209 * with the tag are meant to never be defered.
210 * XXX Should have a way to identify which driver is responsible here.
211 */
212 static void
213 dflt_lock(void *arg, bus_dma_lock_op_t op)
214 {
215 panic("driver error: busdma dflt_lock called");
216 }
217
218 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
219 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
220 /*
221 * Allocate a device specific dma_tag.
222 */
223 int
224 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
225 bus_size_t boundary, bus_addr_t lowaddr,
226 bus_addr_t highaddr, bus_dma_filter_t *filter,
227 void *filterarg, bus_size_t maxsize, int nsegments,
228 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
229 void *lockfuncarg, bus_dma_tag_t *dmat)
230 {
231 bus_dma_tag_t newtag;
232 int error = 0;
233
234 /* Basic sanity checking */
235 if (boundary != 0 && boundary < maxsegsz)
236 maxsegsz = boundary;
237
238 if (maxsegsz == 0) {
239 return (EINVAL);
240 }
241
242 /* Return a NULL tag on failure */
243 *dmat = NULL;
244
245 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF,
246 M_ZERO | M_NOWAIT);
247 if (newtag == NULL) {
248 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
249 __func__, newtag, 0, error);
250 return (ENOMEM);
251 }
252
253 newtag->parent = parent;
254 newtag->alignment = alignment;
255 newtag->boundary = boundary;
256 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
257 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
258 newtag->filter = filter;
259 newtag->filterarg = filterarg;
260 newtag->maxsize = maxsize;
261 newtag->nsegments = nsegments;
262 newtag->maxsegsz = maxsegsz;
263 newtag->flags = flags;
264 newtag->ref_count = 1; /* Count ourself */
265 newtag->map_count = 0;
266 if (lockfunc != NULL) {
267 newtag->lockfunc = lockfunc;
268 newtag->lockfuncarg = lockfuncarg;
269 } else {
270 newtag->lockfunc = dflt_lock;
271 newtag->lockfuncarg = NULL;
272 }
273
274 /* Take into account any restrictions imposed by our parent tag */
275 if (parent != NULL) {
276 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
277 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
278 if (newtag->boundary == 0)
279 newtag->boundary = parent->boundary;
280 else if (parent->boundary != 0)
281 newtag->boundary = MIN(parent->boundary,
282 newtag->boundary);
283 if (newtag->filter == NULL) {
284 /*
285 * Short circuit looking at our parent directly
286 * since we have encapsulated all of its information
287 */
288 newtag->filter = parent->filter;
289 newtag->filterarg = parent->filterarg;
290 newtag->parent = parent->parent;
291 }
292 if (newtag->parent != NULL)
293 atomic_add_int(&parent->ref_count, 1);
294 newtag->iommu = parent->iommu;
295 newtag->iommu_cookie = parent->iommu_cookie;
296 }
297
298 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) && newtag->iommu == NULL)
299 newtag->flags |= BUS_DMA_COULD_BOUNCE;
300
301 if (newtag->alignment > 1)
302 newtag->flags |= BUS_DMA_COULD_BOUNCE;
303
304 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
305 (flags & BUS_DMA_ALLOCNOW) != 0) {
306 struct bounce_zone *bz;
307
308 /* Must bounce */
309
310 if ((error = alloc_bounce_zone(newtag)) != 0) {
311 free(newtag, M_DEVBUF);
312 return (error);
313 }
314 bz = newtag->bounce_zone;
315
316 if (ptoa(bz->total_bpages) < maxsize) {
317 int pages;
318
319 pages = atop(maxsize) - bz->total_bpages;
320
321 /* Add pages to our bounce pool */
322 if (alloc_bounce_pages(newtag, pages) < pages)
323 error = ENOMEM;
324 }
325 /* Performed initial allocation */
326 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
327 }
328
329 if (error != 0) {
330 free(newtag, M_DEVBUF);
331 } else {
332 *dmat = newtag;
333 }
334 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
335 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
336 return (error);
337 }
338
339 int
340 bus_dma_tag_destroy(bus_dma_tag_t dmat)
341 {
342 bus_dma_tag_t dmat_copy;
343 int error;
344
345 error = 0;
346 dmat_copy = dmat;
347
348 if (dmat != NULL) {
349
350 if (dmat->map_count != 0) {
351 error = EBUSY;
352 goto out;
353 }
354
355 while (dmat != NULL) {
356 bus_dma_tag_t parent;
357
358 parent = dmat->parent;
359 atomic_subtract_int(&dmat->ref_count, 1);
360 if (dmat->ref_count == 0) {
361 free(dmat, M_DEVBUF);
362 /*
363 * Last reference count, so
364 * release our reference
365 * count on our parent.
366 */
367 dmat = parent;
368 } else
369 dmat = NULL;
370 }
371 }
372 out:
373 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
374 return (error);
375 }
376
377 /*
378 * Allocate a handle for mapping from kva/uva/physical
379 * address space into bus device space.
380 */
381 int
382 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
383 {
384 int error;
385
386 error = 0;
387
388 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
389 M_NOWAIT | M_ZERO);
390 if (*mapp == NULL) {
391 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
392 __func__, dmat, ENOMEM);
393 return (ENOMEM);
394 }
395
396
397 /*
398 * Bouncing might be required if the driver asks for an active
399 * exclusion region, a data alignment that is stricter than 1, and/or
400 * an active address boundary.
401 */
402 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
403
404 /* Must bounce */
405 struct bounce_zone *bz;
406 int maxpages;
407
408 if (dmat->bounce_zone == NULL) {
409 if ((error = alloc_bounce_zone(dmat)) != 0)
410 return (error);
411 }
412 bz = dmat->bounce_zone;
413
414 /* Initialize the new map */
415 STAILQ_INIT(&((*mapp)->bpages));
416
417 /*
418 * Attempt to add pages to our pool on a per-instance
419 * basis up to a sane limit.
420 */
421 if (dmat->alignment > 1)
422 maxpages = MAX_BPAGES;
423 else
424 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
425 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
426 || (bz->map_count > 0 && bz->total_bpages < maxpages)) {
427 int pages;
428
429 pages = MAX(atop(dmat->maxsize), 1);
430 pages = MIN(maxpages - bz->total_bpages, pages);
431 pages = MAX(pages, 1);
432 if (alloc_bounce_pages(dmat, pages) < pages)
433 error = ENOMEM;
434
435 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
436 if (error == 0)
437 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
438 } else {
439 error = 0;
440 }
441 }
442 bz->map_count++;
443 }
444
445 (*mapp)->nsegs = 0;
446 (*mapp)->segments = (bus_dma_segment_t *)malloc(
447 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
448 M_NOWAIT);
449 if ((*mapp)->segments == NULL) {
450 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
451 __func__, dmat, ENOMEM);
452 return (ENOMEM);
453 }
454
455 if (error == 0)
456 dmat->map_count++;
457 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
458 __func__, dmat, dmat->flags, error);
459 return (error);
460 }
461
462 /*
463 * Destroy a handle for mapping from kva/uva/physical
464 * address space into bus device space.
465 */
466 int
467 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
468 {
469 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
470 if (STAILQ_FIRST(&map->bpages) != NULL) {
471 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
472 __func__, dmat, EBUSY);
473 return (EBUSY);
474 }
475 if (dmat->bounce_zone)
476 dmat->bounce_zone->map_count--;
477 }
478 free(map->segments, M_DEVBUF);
479 free(map, M_DEVBUF);
480 dmat->map_count--;
481 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
482 return (0);
483 }
484
485
486 /*
487 * Allocate a piece of memory that can be efficiently mapped into
488 * bus device space based on the constraints lited in the dma tag.
489 * A dmamap to for use with dmamap_load is also allocated.
490 */
491 int
492 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
493 bus_dmamap_t *mapp)
494 {
495 vm_memattr_t attr;
496 int mflags;
497
498 if (flags & BUS_DMA_NOWAIT)
499 mflags = M_NOWAIT;
500 else
501 mflags = M_WAITOK;
502
503 bus_dmamap_create(dmat, flags, mapp);
504
505 if (flags & BUS_DMA_ZERO)
506 mflags |= M_ZERO;
507 #ifdef NOTYET
508 if (flags & BUS_DMA_NOCACHE)
509 attr = VM_MEMATTR_UNCACHEABLE;
510 else
511 #endif
512 attr = VM_MEMATTR_DEFAULT;
513
514 /*
515 * XXX:
516 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact
517 * alignment guarantees of malloc need to be nailed down, and the
518 * code below should be rewritten to take that into account.
519 *
520 * In the meantime, we'll warn the user if malloc gets it wrong.
521 */
522 if ((dmat->maxsize <= PAGE_SIZE) &&
523 (dmat->alignment < dmat->maxsize) &&
524 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem) &&
525 attr == VM_MEMATTR_DEFAULT) {
526 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
527 } else {
528 /*
529 * XXX Use Contigmalloc until it is merged into this facility
530 * and handles multi-seg allocations. Nobody is doing
531 * multi-seg allocations yet though.
532 * XXX Certain AGP hardware does.
533 */
534 *vaddr = (void *)kmem_alloc_contig(kernel_map, dmat->maxsize,
535 mflags, 0ul, dmat->lowaddr, dmat->alignment ?
536 dmat->alignment : 1ul, dmat->boundary, attr);
537 (*mapp)->contigalloc = 1;
538 }
539 if (*vaddr == NULL) {
540 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
541 __func__, dmat, dmat->flags, ENOMEM);
542 return (ENOMEM);
543 } else if (vtophys(*vaddr) & (dmat->alignment - 1)) {
544 printf("bus_dmamem_alloc failed to align memory properly.\n");
545 }
546 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
547 __func__, dmat, dmat->flags, 0);
548 return (0);
549 }
550
551 /*
552 * Free a piece of memory and it's allociated dmamap, that was allocated
553 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
554 */
555 void
556 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
557 {
558
559 if (!map->contigalloc)
560 free(vaddr, M_DEVBUF);
561 else
562 kmem_free(kernel_map, (vm_offset_t)vaddr, dmat->maxsize);
563 bus_dmamap_destroy(dmat, map);
564 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
565 }
566
567 static void
568 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf,
569 bus_size_t buflen, int flags)
570 {
571 bus_addr_t curaddr;
572 bus_size_t sgsize;
573
574 if (map->pagesneeded == 0) {
575 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
576 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
577 dmat->boundary, dmat->alignment);
578 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map, map->pagesneeded);
579 /*
580 * Count the number of bounce pages
581 * needed in order to complete this transfer
582 */
583 curaddr = buf;
584 while (buflen != 0) {
585 sgsize = MIN(buflen, dmat->maxsegsz);
586 if (run_filter(dmat, curaddr) != 0) {
587 sgsize = MIN(sgsize, PAGE_SIZE);
588 map->pagesneeded++;
589 }
590 curaddr += sgsize;
591 buflen -= sgsize;
592 }
593 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
594 }
595 }
596
597 static void
598 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap,
599 void *buf, bus_size_t buflen, int flags)
600 {
601 vm_offset_t vaddr;
602 vm_offset_t vendaddr;
603 bus_addr_t paddr;
604
605 if (map->pagesneeded == 0) {
606 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
607 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
608 dmat->boundary, dmat->alignment);
609 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map, map->pagesneeded);
610 /*
611 * Count the number of bounce pages
612 * needed in order to complete this transfer
613 */
614 vaddr = (vm_offset_t)buf;
615 vendaddr = (vm_offset_t)buf + buflen;
616
617 while (vaddr < vendaddr) {
618 bus_size_t sg_len;
619
620 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK);
621 if (pmap == kernel_pmap)
622 paddr = pmap_kextract(vaddr);
623 else
624 paddr = pmap_extract(pmap, vaddr);
625 if (run_filter(dmat, paddr) != 0) {
626 sg_len = roundup2(sg_len, dmat->alignment);
627 map->pagesneeded++;
628 }
629 vaddr += sg_len;
630 }
631 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
632 }
633 }
634
635 static int
636 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags)
637 {
638
639 /* Reserve Necessary Bounce Pages */
640 mtx_lock(&bounce_lock);
641 if (flags & BUS_DMA_NOWAIT) {
642 if (reserve_bounce_pages(dmat, map, 0) != 0) {
643 mtx_unlock(&bounce_lock);
644 return (ENOMEM);
645 }
646 } else {
647 if (reserve_bounce_pages(dmat, map, 1) != 0) {
648 /* Queue us for resources */
649 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
650 map, links);
651 mtx_unlock(&bounce_lock);
652 return (EINPROGRESS);
653 }
654 }
655 mtx_unlock(&bounce_lock);
656
657 return (0);
658 }
659
660 /*
661 * Add a single contiguous physical range to the segment list.
662 */
663 static int
664 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, bus_addr_t curaddr,
665 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp)
666 {
667 bus_addr_t baddr, bmask;
668 int seg;
669
670 /*
671 * Make sure we don't cross any boundaries.
672 */
673 bmask = ~(dmat->boundary - 1);
674 if (dmat->boundary > 0) {
675 baddr = (curaddr + dmat->boundary) & bmask;
676 if (sgsize > (baddr - curaddr))
677 sgsize = (baddr - curaddr);
678 }
679
680 /*
681 * Insert chunk into a segment, coalescing with
682 * previous segment if possible.
683 */
684 seg = *segp;
685 if (seg == -1) {
686 seg = 0;
687 segs[seg].ds_addr = curaddr;
688 segs[seg].ds_len = sgsize;
689 } else {
690 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len &&
691 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
692 (dmat->boundary == 0 ||
693 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
694 segs[seg].ds_len += sgsize;
695 else {
696 if (++seg >= dmat->nsegments)
697 return (0);
698 segs[seg].ds_addr = curaddr;
699 segs[seg].ds_len = sgsize;
700 }
701 }
702 *segp = seg;
703 return (sgsize);
704 }
705
706 /*
707 * Utility function to load a physical buffer. segp contains
708 * the starting segment on entrace, and the ending segment on exit.
709 */
710 int
711 _bus_dmamap_load_phys(bus_dma_tag_t dmat,
712 bus_dmamap_t map,
713 vm_paddr_t buf, bus_size_t buflen,
714 int flags,
715 bus_dma_segment_t *segs,
716 int *segp)
717 {
718 bus_addr_t curaddr;
719 bus_size_t sgsize;
720 int error;
721
722 if (segs == NULL)
723 segs = map->segments;
724
725 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
726 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags);
727 if (map->pagesneeded != 0) {
728 error = _bus_dmamap_reserve_pages(dmat, map, flags);
729 if (error)
730 return (error);
731 }
732 }
733
734 while (buflen > 0) {
735 curaddr = buf;
736 sgsize = MIN(buflen, dmat->maxsegsz);
737 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
738 sgsize = MIN(sgsize, PAGE_SIZE);
739 curaddr = add_bounce_page(dmat, map, 0, curaddr,
740 sgsize);
741 }
742 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
743 segp);
744 if (sgsize == 0)
745 break;
746 buf += sgsize;
747 buflen -= sgsize;
748 }
749
750 /*
751 * Did we fit?
752 */
753 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
754 }
755
756 /*
757 * Utility function to load a linear buffer. segp contains
758 * the starting segment on entrance, and the ending segment on exit.
759 */
760 int
761 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
762 bus_dmamap_t map,
763 void *buf, bus_size_t buflen,
764 pmap_t pmap,
765 int flags,
766 bus_dma_segment_t *segs,
767 int *segp)
768 {
769 bus_size_t sgsize;
770 bus_addr_t curaddr;
771 vm_offset_t vaddr;
772 int error;
773
774 if (segs == NULL)
775 segs = map->segments;
776
777 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
778 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags);
779 if (map->pagesneeded != 0) {
780 error = _bus_dmamap_reserve_pages(dmat, map, flags);
781 if (error)
782 return (error);
783 }
784 }
785
786 vaddr = (vm_offset_t)buf;
787
788 while (buflen > 0) {
789 bus_size_t max_sgsize;
790
791 /*
792 * Get the physical address for this segment.
793 */
794 if (pmap == kernel_pmap)
795 curaddr = pmap_kextract(vaddr);
796 else
797 curaddr = pmap_extract(pmap, vaddr);
798
799 /*
800 * Compute the segment size, and adjust counts.
801 */
802 max_sgsize = MIN(buflen, dmat->maxsegsz);
803 sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK);
804 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
805 sgsize = roundup2(sgsize, dmat->alignment);
806 sgsize = MIN(sgsize, max_sgsize);
807 curaddr = add_bounce_page(dmat, map, vaddr, curaddr,
808 sgsize);
809 } else {
810 sgsize = MIN(sgsize, max_sgsize);
811 }
812
813 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
814 segp);
815 if (sgsize == 0)
816 break;
817 vaddr += sgsize;
818 buflen -= sgsize;
819 }
820
821 /*
822 * Did we fit?
823 */
824 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
825 }
826
827 void
828 __bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map,
829 struct memdesc *mem, bus_dmamap_callback_t *callback,
830 void *callback_arg)
831 {
832
833 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
834 map->dmat = dmat;
835 map->mem = *mem;
836 map->callback = callback;
837 map->callback_arg = callback_arg;
838 }
839 }
840
841 bus_dma_segment_t *
842 _bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map,
843 bus_dma_segment_t *segs, int nsegs, int error)
844 {
845
846 map->nsegs = nsegs;
847 if (segs != NULL)
848 memcpy(map->segments, segs, map->nsegs*sizeof(segs[0]));
849 if (dmat->iommu != NULL)
850 IOMMU_MAP(dmat->iommu, map->segments, &map->nsegs,
851 dmat->lowaddr, dmat->highaddr, dmat->alignment,
852 dmat->boundary, dmat->iommu_cookie);
853
854 if (segs != NULL)
855 memcpy(segs, map->segments, map->nsegs*sizeof(segs[0]));
856 else
857 segs = map->segments;
858
859 return (segs);
860 }
861
862 /*
863 * Release the mapping held by map.
864 */
865 void
866 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
867 {
868 struct bounce_page *bpage;
869
870 if (dmat->iommu) {
871 IOMMU_UNMAP(dmat->iommu, map->segments, map->nsegs, dmat->iommu_cookie);
872 map->nsegs = 0;
873 }
874
875 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
876 STAILQ_REMOVE_HEAD(&map->bpages, links);
877 free_bounce_page(dmat, bpage);
878 }
879 }
880
881 void
882 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
883 {
884 struct bounce_page *bpage;
885
886 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
887 /*
888 * Handle data bouncing. We might also
889 * want to add support for invalidating
890 * the caches on broken hardware
891 */
892 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
893 "performing bounce", __func__, op, dmat, dmat->flags);
894
895 if (op & BUS_DMASYNC_PREWRITE) {
896 while (bpage != NULL) {
897 if (bpage->datavaddr != 0)
898 bcopy((void *)bpage->datavaddr,
899 (void *)bpage->vaddr,
900 bpage->datacount);
901 else
902 physcopyout(bpage->dataaddr,
903 (void *)bpage->vaddr,
904 bpage->datacount);
905 bpage = STAILQ_NEXT(bpage, links);
906 }
907 dmat->bounce_zone->total_bounced++;
908 }
909
910 if (op & BUS_DMASYNC_POSTREAD) {
911 while (bpage != NULL) {
912 if (bpage->datavaddr != 0)
913 bcopy((void *)bpage->vaddr,
914 (void *)bpage->datavaddr,
915 bpage->datacount);
916 else
917 physcopyin((void *)bpage->vaddr,
918 bpage->dataaddr, bpage->datacount);
919 bpage = STAILQ_NEXT(bpage, links);
920 }
921 dmat->bounce_zone->total_bounced++;
922 }
923 }
924 }
925
926 static void
927 init_bounce_pages(void *dummy __unused)
928 {
929
930 total_bpages = 0;
931 STAILQ_INIT(&bounce_zone_list);
932 STAILQ_INIT(&bounce_map_waitinglist);
933 STAILQ_INIT(&bounce_map_callbacklist);
934 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
935 }
936 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
937
938 static struct sysctl_ctx_list *
939 busdma_sysctl_tree(struct bounce_zone *bz)
940 {
941 return (&bz->sysctl_tree);
942 }
943
944 static struct sysctl_oid *
945 busdma_sysctl_tree_top(struct bounce_zone *bz)
946 {
947 return (bz->sysctl_tree_top);
948 }
949
950 static int
951 alloc_bounce_zone(bus_dma_tag_t dmat)
952 {
953 struct bounce_zone *bz;
954
955 /* Check to see if we already have a suitable zone */
956 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
957 if ((dmat->alignment <= bz->alignment)
958 && (dmat->lowaddr >= bz->lowaddr)) {
959 dmat->bounce_zone = bz;
960 return (0);
961 }
962 }
963
964 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
965 M_NOWAIT | M_ZERO)) == NULL)
966 return (ENOMEM);
967
968 STAILQ_INIT(&bz->bounce_page_list);
969 bz->free_bpages = 0;
970 bz->reserved_bpages = 0;
971 bz->active_bpages = 0;
972 bz->lowaddr = dmat->lowaddr;
973 bz->alignment = MAX(dmat->alignment, PAGE_SIZE);
974 bz->map_count = 0;
975 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
976 busdma_zonecount++;
977 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
978 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
979 dmat->bounce_zone = bz;
980
981 sysctl_ctx_init(&bz->sysctl_tree);
982 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
983 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
984 CTLFLAG_RD, 0, "");
985 if (bz->sysctl_tree_top == NULL) {
986 sysctl_ctx_free(&bz->sysctl_tree);
987 return (0); /* XXX error code? */
988 }
989
990 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
991 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
992 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
993 "Total bounce pages");
994 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
995 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
996 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
997 "Free bounce pages");
998 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
999 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1000 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1001 "Reserved bounce pages");
1002 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1003 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1004 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1005 "Active bounce pages");
1006 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1007 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1008 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1009 "Total bounce requests");
1010 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1011 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1012 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1013 "Total bounce requests that were deferred");
1014 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1015 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1016 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1017 SYSCTL_ADD_UAUTO(busdma_sysctl_tree(bz),
1018 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1019 "alignment", CTLFLAG_RD, &bz->alignment, "");
1020
1021 return (0);
1022 }
1023
1024 static int
1025 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1026 {
1027 struct bounce_zone *bz;
1028 int count;
1029
1030 bz = dmat->bounce_zone;
1031 count = 0;
1032 while (numpages > 0) {
1033 struct bounce_page *bpage;
1034
1035 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1036 M_NOWAIT | M_ZERO);
1037
1038 if (bpage == NULL)
1039 break;
1040 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1041 M_NOWAIT, 0ul,
1042 bz->lowaddr,
1043 PAGE_SIZE,
1044 0);
1045 if (bpage->vaddr == 0) {
1046 free(bpage, M_DEVBUF);
1047 break;
1048 }
1049 bpage->busaddr = pmap_kextract(bpage->vaddr);
1050 mtx_lock(&bounce_lock);
1051 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1052 total_bpages++;
1053 bz->total_bpages++;
1054 bz->free_bpages++;
1055 mtx_unlock(&bounce_lock);
1056 count++;
1057 numpages--;
1058 }
1059 return (count);
1060 }
1061
1062 static int
1063 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1064 {
1065 struct bounce_zone *bz;
1066 int pages;
1067
1068 mtx_assert(&bounce_lock, MA_OWNED);
1069 bz = dmat->bounce_zone;
1070 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1071 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1072 return (map->pagesneeded - (map->pagesreserved + pages));
1073 bz->free_bpages -= pages;
1074 bz->reserved_bpages += pages;
1075 map->pagesreserved += pages;
1076 pages = map->pagesneeded - map->pagesreserved;
1077
1078 return (pages);
1079 }
1080
1081 static bus_addr_t
1082 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1083 bus_addr_t addr, bus_size_t size)
1084 {
1085 struct bounce_zone *bz;
1086 struct bounce_page *bpage;
1087
1088 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1089
1090 bz = dmat->bounce_zone;
1091 if (map->pagesneeded == 0)
1092 panic("add_bounce_page: map doesn't need any pages");
1093 map->pagesneeded--;
1094
1095 if (map->pagesreserved == 0)
1096 panic("add_bounce_page: map doesn't need any pages");
1097 map->pagesreserved--;
1098
1099 mtx_lock(&bounce_lock);
1100 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1101 if (bpage == NULL)
1102 panic("add_bounce_page: free page list is empty");
1103
1104 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1105 bz->reserved_bpages--;
1106 bz->active_bpages++;
1107 mtx_unlock(&bounce_lock);
1108
1109 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1110 /* Page offset needs to be preserved. */
1111 bpage->vaddr |= addr & PAGE_MASK;
1112 bpage->busaddr |= addr & PAGE_MASK;
1113 }
1114 bpage->datavaddr = vaddr;
1115 bpage->dataaddr = addr;
1116 bpage->datacount = size;
1117 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1118 return (bpage->busaddr);
1119 }
1120
1121 static void
1122 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1123 {
1124 struct bus_dmamap *map;
1125 struct bounce_zone *bz;
1126
1127 bz = dmat->bounce_zone;
1128 bpage->datavaddr = 0;
1129 bpage->datacount = 0;
1130 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1131 /*
1132 * Reset the bounce page to start at offset 0. Other uses
1133 * of this bounce page may need to store a full page of
1134 * data and/or assume it starts on a page boundary.
1135 */
1136 bpage->vaddr &= ~PAGE_MASK;
1137 bpage->busaddr &= ~PAGE_MASK;
1138 }
1139
1140 mtx_lock(&bounce_lock);
1141 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1142 bz->free_bpages++;
1143 bz->active_bpages--;
1144 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1145 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1146 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1147 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1148 map, links);
1149 busdma_swi_pending = 1;
1150 bz->total_deferred++;
1151 swi_sched(vm_ih, 0);
1152 }
1153 }
1154 mtx_unlock(&bounce_lock);
1155 }
1156
1157 void
1158 busdma_swi(void)
1159 {
1160 bus_dma_tag_t dmat;
1161 struct bus_dmamap *map;
1162
1163 mtx_lock(&bounce_lock);
1164 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1165 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1166 mtx_unlock(&bounce_lock);
1167 dmat = map->dmat;
1168 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1169 bus_dmamap_load_mem(map->dmat, map, &map->mem,
1170 map->callback, map->callback_arg,
1171 BUS_DMA_WAITOK);
1172 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1173 mtx_lock(&bounce_lock);
1174 }
1175 mtx_unlock(&bounce_lock);
1176 }
1177
1178 int
1179 bus_dma_tag_set_iommu(bus_dma_tag_t tag, struct device *iommu, void *cookie)
1180 {
1181 tag->iommu = iommu;
1182 tag->iommu_cookie = cookie;
1183
1184 return (0);
1185 }
1186
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