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/mutex.h> 44 #include <sys/mbuf.h> 45 #include <sys/uio.h> 46 #include <sys/sysctl.h> 47 48 #include <vm/vm.h> 49 #include <vm/vm_page.h> 50 #include <vm/vm_map.h> 51 52 #include <machine/atomic.h> 53 #include <machine/bus.h> 54 #include <machine/md_var.h> 55 56 #define MAX_BPAGES 8192 57 58 struct bounce_zone; 59 60 struct bus_dma_tag { 61 bus_dma_tag_t parent; 62 bus_size_t alignment; 63 bus_size_t boundary; 64 bus_addr_t lowaddr; 65 bus_addr_t highaddr; 66 bus_dma_filter_t *filter; 67 void *filterarg; 68 bus_size_t maxsize; 69 u_int nsegments; 70 bus_size_t maxsegsz; 71 int flags; 72 int ref_count; 73 int map_count; 74 bus_dma_lock_t *lockfunc; 75 void *lockfuncarg; 76 bus_dma_segment_t *segments; 77 struct bounce_zone *bounce_zone; 78 }; 79 80 struct bounce_page { 81 vm_offset_t vaddr; /* kva of bounce buffer */ 82 bus_addr_t busaddr; /* Physical address */ 83 vm_offset_t datavaddr; /* kva of client data */ 84 bus_size_t datacount; /* client data count */ 85 STAILQ_ENTRY(bounce_page) links; 86 }; 87 88 int busdma_swi_pending; 89 90 struct bounce_zone { 91 STAILQ_ENTRY(bounce_zone) links; 92 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 93 int total_bpages; 94 int free_bpages; 95 int reserved_bpages; 96 int active_bpages; 97 int total_bounced; 98 int total_deferred; 99 int map_count; 100 bus_size_t alignment; 101 bus_addr_t lowaddr; 102 char zoneid[8]; 103 char lowaddrid[20]; 104 struct sysctl_ctx_list sysctl_tree; 105 struct sysctl_oid *sysctl_tree_top; 106 }; 107 108 static struct mtx bounce_lock; 109 static int total_bpages; 110 static int busdma_zonecount; 111 static STAILQ_HEAD(, bounce_zone) bounce_zone_list; 112 113 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 114 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 115 "Total bounce pages"); 116 117 struct bus_dmamap { 118 struct bp_list bpages; 119 int pagesneeded; 120 int pagesreserved; 121 bus_dma_tag_t dmat; 122 void *buf; /* unmapped buffer pointer */ 123 bus_size_t buflen; /* unmapped buffer length */ 124 bus_dmamap_callback_t *callback; 125 void *callback_arg; 126 STAILQ_ENTRY(bus_dmamap) links; 127 }; 128 129 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 130 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 131 static struct bus_dmamap nobounce_dmamap; 132 133 static void init_bounce_pages(void *dummy); 134 static int alloc_bounce_zone(bus_dma_tag_t dmat); 135 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 136 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 137 int commit); 138 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 139 vm_offset_t vaddr, bus_size_t size); 140 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 141 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr); 142 143 /* 144 * Return true if a match is made. 145 * 146 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'. 147 * 148 * If paddr is within the bounds of the dma tag then call the filter callback 149 * to check for a match, if there is no filter callback then assume a match. 150 */ 151 static __inline int 152 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr) 153 { 154 int retval; 155 156 retval = 0; 157 158 do { 159 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) 160 || ((paddr & (dmat->alignment - 1)) != 0)) 161 && (dmat->filter == NULL 162 || (*dmat->filter)(dmat->filterarg, paddr) != 0)) 163 retval = 1; 164 165 dmat = dmat->parent; 166 } while (retval == 0 && dmat != NULL); 167 return (retval); 168 } 169 170 /* 171 * Convenience function for manipulating driver locks from busdma (during 172 * busdma_swi, for example). Drivers that don't provide their own locks 173 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own 174 * non-mutex locking scheme don't have to use this at all. 175 */ 176 void 177 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op) 178 { 179 struct mtx *dmtx; 180 181 dmtx = (struct mtx *)arg; 182 switch (op) { 183 case BUS_DMA_LOCK: 184 mtx_lock(dmtx); 185 break; 186 case BUS_DMA_UNLOCK: 187 mtx_unlock(dmtx); 188 break; 189 default: 190 panic("Unknown operation 0x%x for busdma_lock_mutex!", op); 191 } 192 } 193 194 /* 195 * dflt_lock should never get called. It gets put into the dma tag when 196 * lockfunc == NULL, which is only valid if the maps that are associated 197 * with the tag are meant to never be defered. 198 * XXX Should have a way to identify which driver is responsible here. 199 */ 200 static void 201 dflt_lock(void *arg, bus_dma_lock_op_t op) 202 { 203 panic("driver error: busdma dflt_lock called"); 204 } 205 206 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3 207 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 208 /* 209 * Allocate a device specific dma_tag. 210 */ 211 int 212 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 213 bus_size_t boundary, bus_addr_t lowaddr, 214 bus_addr_t highaddr, bus_dma_filter_t *filter, 215 void *filterarg, bus_size_t maxsize, int nsegments, 216 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 217 void *lockfuncarg, bus_dma_tag_t *dmat) 218 { 219 bus_dma_tag_t newtag; 220 int error = 0; 221 222 /* Basic sanity checking */ 223 if (boundary != 0 && boundary < maxsegsz) 224 maxsegsz = boundary; 225 226 if (maxsegsz == 0) { 227 return (EINVAL); 228 } 229 230 /* Return a NULL tag on failure */ 231 *dmat = NULL; 232 233 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, 234 M_ZERO | M_NOWAIT); 235 if (newtag == NULL) { 236 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 237 __func__, newtag, 0, error); 238 return (ENOMEM); 239 } 240 241 newtag->parent = parent; 242 newtag->alignment = alignment; 243 newtag->boundary = boundary; 244 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 245 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1); 246 newtag->filter = filter; 247 newtag->filterarg = filterarg; 248 newtag->maxsize = maxsize; 249 newtag->nsegments = nsegments; 250 newtag->maxsegsz = maxsegsz; 251 newtag->flags = flags; 252 newtag->ref_count = 1; /* Count ourself */ 253 newtag->map_count = 0; 254 if (lockfunc != NULL) { 255 newtag->lockfunc = lockfunc; 256 newtag->lockfuncarg = lockfuncarg; 257 } else { 258 newtag->lockfunc = dflt_lock; 259 newtag->lockfuncarg = NULL; 260 } 261 newtag->segments = NULL; 262 263 /* Take into account any restrictions imposed by our parent tag */ 264 if (parent != NULL) { 265 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 266 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 267 if (newtag->boundary == 0) 268 newtag->boundary = parent->boundary; 269 else if (parent->boundary != 0) 270 newtag->boundary = MIN(parent->boundary, 271 newtag->boundary); 272 if (newtag->filter == NULL) { 273 /* 274 * Short circuit looking at our parent directly 275 * since we have encapsulated all of its information 276 */ 277 newtag->filter = parent->filter; 278 newtag->filterarg = parent->filterarg; 279 newtag->parent = parent->parent; 280 } 281 if (newtag->parent != NULL) 282 atomic_add_int(&parent->ref_count, 1); 283 } 284 285 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) 286 || newtag->alignment > 1) 287 newtag->flags |= BUS_DMA_COULD_BOUNCE; 288 289 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) && 290 (flags & BUS_DMA_ALLOCNOW) != 0) { 291 struct bounce_zone *bz; 292 293 /* Must bounce */ 294 295 if ((error = alloc_bounce_zone(newtag)) != 0) { 296 free(newtag, M_DEVBUF); 297 return (error); 298 } 299 bz = newtag->bounce_zone; 300 301 if (ptoa(bz->total_bpages) < maxsize) { 302 int pages; 303 304 pages = atop(maxsize) - bz->total_bpages; 305 306 /* Add pages to our bounce pool */ 307 if (alloc_bounce_pages(newtag, pages) < pages) 308 error = ENOMEM; 309 } 310 /* Performed initial allocation */ 311 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 312 } 313 314 if (error != 0) { 315 free(newtag, M_DEVBUF); 316 } else { 317 *dmat = newtag; 318 } 319 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 320 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error); 321 return (error); 322 } 323 324 int 325 bus_dma_tag_destroy(bus_dma_tag_t dmat) 326 { 327 bus_dma_tag_t dmat_copy; 328 int error; 329 330 error = 0; 331 dmat_copy = dmat; 332 333 if (dmat != NULL) { 334 335 if (dmat->map_count != 0) { 336 error = EBUSY; 337 goto out; 338 } 339 340 while (dmat != NULL) { 341 bus_dma_tag_t parent; 342 343 parent = dmat->parent; 344 atomic_subtract_int(&dmat->ref_count, 1); 345 if (dmat->ref_count == 0) { 346 if (dmat->segments != NULL) 347 free(dmat->segments, M_DEVBUF); 348 free(dmat, M_DEVBUF); 349 /* 350 * Last reference count, so 351 * release our reference 352 * count on our parent. 353 */ 354 dmat = parent; 355 } else 356 dmat = NULL; 357 } 358 } 359 out: 360 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 361 return (error); 362 } 363 364 /* 365 * Allocate a handle for mapping from kva/uva/physical 366 * address space into bus device space. 367 */ 368 int 369 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 370 { 371 int error; 372 373 error = 0; 374 375 if (dmat->segments == NULL) { 376 dmat->segments = (bus_dma_segment_t *)malloc( 377 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 378 M_NOWAIT); 379 if (dmat->segments == NULL) { 380 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 381 __func__, dmat, ENOMEM); 382 return (ENOMEM); 383 } 384 } 385 386 /* 387 * Bouncing might be required if the driver asks for an active 388 * exclusion region, a data alignment that is stricter than 1, and/or 389 * an active address boundary. 390 */ 391 if (dmat->flags & BUS_DMA_COULD_BOUNCE) { 392 393 /* Must bounce */ 394 struct bounce_zone *bz; 395 int maxpages; 396 397 if (dmat->bounce_zone == NULL) { 398 if ((error = alloc_bounce_zone(dmat)) != 0) 399 return (error); 400 } 401 bz = dmat->bounce_zone; 402 403 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF, 404 M_NOWAIT | M_ZERO); 405 if (*mapp == NULL) { 406 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 407 __func__, dmat, ENOMEM); 408 return (ENOMEM); 409 } 410 411 /* Initialize the new map */ 412 STAILQ_INIT(&((*mapp)->bpages)); 413 414 /* 415 * Attempt to add pages to our pool on a per-instance 416 * basis up to a sane limit. 417 */ 418 if (dmat->alignment > 1) 419 maxpages = MAX_BPAGES; 420 else 421 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr)); 422 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 423 || (bz->map_count > 0 && bz->total_bpages < maxpages)) { 424 int pages; 425 426 pages = MAX(atop(dmat->maxsize), 1); 427 pages = MIN(maxpages - bz->total_bpages, pages); 428 pages = MAX(pages, 1); 429 if (alloc_bounce_pages(dmat, pages) < pages) 430 error = ENOMEM; 431 432 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 433 if (error == 0) 434 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 435 } else { 436 error = 0; 437 } 438 } 439 bz->map_count++; 440 } else { 441 *mapp = NULL; 442 } 443 if (error == 0) 444 dmat->map_count++; 445 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 446 __func__, dmat, dmat->flags, error); 447 return (error); 448 } 449 450 /* 451 * Destroy a handle for mapping from kva/uva/physical 452 * address space into bus device space. 453 */ 454 int 455 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 456 { 457 if (map != NULL && map != &nobounce_dmamap) { 458 if (STAILQ_FIRST(&map->bpages) != NULL) { 459 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 460 __func__, dmat, EBUSY); 461 return (EBUSY); 462 } 463 if (dmat->bounce_zone) 464 dmat->bounce_zone->map_count--; 465 free(map, M_DEVBUF); 466 } 467 dmat->map_count--; 468 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 469 return (0); 470 } 471 472 473 /* 474 * Allocate a piece of memory that can be efficiently mapped into 475 * bus device space based on the constraints lited in the dma tag. 476 * A dmamap to for use with dmamap_load is also allocated. 477 */ 478 int 479 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 480 bus_dmamap_t *mapp) 481 { 482 int mflags; 483 484 if (flags & BUS_DMA_NOWAIT) 485 mflags = M_NOWAIT; 486 else 487 mflags = M_WAITOK; 488 489 /* If we succeed, no mapping/bouncing will be required */ 490 *mapp = NULL; 491 492 if (dmat->segments == NULL) { 493 dmat->segments = (bus_dma_segment_t *)malloc( 494 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 495 mflags); 496 if (dmat->segments == NULL) { 497 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 498 __func__, dmat, dmat->flags, ENOMEM); 499 return (ENOMEM); 500 } 501 } 502 if (flags & BUS_DMA_ZERO) 503 mflags |= M_ZERO; 504 505 /* 506 * XXX: 507 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact 508 * alignment guarantees of malloc need to be nailed down, and the 509 * code below should be rewritten to take that into account. 510 * 511 * In the meantime, we'll warn the user if malloc gets it wrong. 512 */ 513 if ((dmat->maxsize <= PAGE_SIZE) && 514 (dmat->alignment < dmat->maxsize) && 515 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) { 516 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags); 517 } else { 518 /* 519 * XXX Use Contigmalloc until it is merged into this facility 520 * and handles multi-seg allocations. Nobody is doing 521 * multi-seg allocations yet though. 522 * XXX Certain AGP hardware does. 523 */ 524 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 525 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul, 526 dmat->boundary); 527 } 528 if (*vaddr == NULL) { 529 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 530 __func__, dmat, dmat->flags, ENOMEM); 531 return (ENOMEM); 532 } else if (vtophys(*vaddr) & (dmat->alignment - 1)) { 533 printf("bus_dmamem_alloc failed to align memory properly.\n"); 534 } 535 #ifdef NOTYET 536 if (flags & BUS_DMA_NOCACHE) 537 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize, 538 PAT_UNCACHEABLE); 539 #endif 540 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 541 __func__, dmat, dmat->flags, 0); 542 return (0); 543 } 544 545 /* 546 * Free a piece of memory and it's allociated dmamap, that was allocated 547 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 548 */ 549 void 550 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 551 { 552 /* 553 * dmamem does not need to be bounced, so the map should be 554 * NULL 555 */ 556 if (map != NULL) 557 panic("bus_dmamem_free: Invalid map freed\n"); 558 #ifdef NOTYET 559 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK); 560 #endif 561 if ((dmat->maxsize <= PAGE_SIZE) && 562 (dmat->alignment < dmat->maxsize) && 563 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) 564 free(vaddr, M_DEVBUF); 565 else { 566 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 567 } 568 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags); 569 } 570 571 /* 572 * Utility function to load a linear buffer. lastaddrp holds state 573 * between invocations (for multiple-buffer loads). segp contains 574 * the starting segment on entrance, and the ending segment on exit. 575 * first indicates if this is the first invocation of this function. 576 */ 577 static __inline int 578 _bus_dmamap_load_buffer(bus_dma_tag_t dmat, 579 bus_dmamap_t map, 580 void *buf, bus_size_t buflen, 581 pmap_t pmap, 582 int flags, 583 bus_addr_t *lastaddrp, 584 bus_dma_segment_t *segs, 585 int *segp, 586 int first) 587 { 588 bus_size_t sgsize; 589 bus_addr_t curaddr, lastaddr, baddr, bmask; 590 vm_offset_t vaddr; 591 bus_addr_t paddr; 592 int seg; 593 594 if (map == NULL) 595 map = &nobounce_dmamap; 596 597 if ((map != &nobounce_dmamap && map->pagesneeded == 0) 598 && ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0)) { 599 vm_offset_t vendaddr; 600 601 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 602 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem), 603 dmat->boundary, dmat->alignment); 604 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 605 map, &nobounce_dmamap, map->pagesneeded); 606 /* 607 * Count the number of bounce pages 608 * needed in order to complete this transfer 609 */ 610 vaddr = (vm_offset_t)buf; 611 vendaddr = (vm_offset_t)buf + buflen; 612 613 while (vaddr < vendaddr) { 614 bus_size_t sg_len; 615 616 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK); 617 if (pmap) 618 paddr = pmap_extract(pmap, vaddr); 619 else 620 paddr = pmap_kextract(vaddr); 621 if (run_filter(dmat, paddr) != 0) { 622 sg_len = roundup2(sg_len, dmat->alignment); 623 map->pagesneeded++; 624 } 625 vaddr += sg_len; 626 } 627 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 628 } 629 630 /* Reserve Necessary Bounce Pages */ 631 if (map->pagesneeded != 0) { 632 mtx_lock(&bounce_lock); 633 if (flags & BUS_DMA_NOWAIT) { 634 if (reserve_bounce_pages(dmat, map, 0) != 0) { 635 mtx_unlock(&bounce_lock); 636 return (ENOMEM); 637 } 638 } else { 639 if (reserve_bounce_pages(dmat, map, 1) != 0) { 640 /* Queue us for resources */ 641 map->dmat = dmat; 642 map->buf = buf; 643 map->buflen = buflen; 644 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, 645 map, links); 646 mtx_unlock(&bounce_lock); 647 return (EINPROGRESS); 648 } 649 } 650 mtx_unlock(&bounce_lock); 651 } 652 653 vaddr = (vm_offset_t)buf; 654 lastaddr = *lastaddrp; 655 bmask = ~(dmat->boundary - 1); 656 657 for (seg = *segp; buflen > 0 ; ) { 658 bus_size_t max_sgsize; 659 660 /* 661 * Get the physical address for this segment. 662 */ 663 if (pmap) 664 curaddr = pmap_extract(pmap, vaddr); 665 else 666 curaddr = pmap_kextract(vaddr); 667 668 /* 669 * Compute the segment size, and adjust counts. 670 */ 671 max_sgsize = MIN(buflen, dmat->maxsegsz); 672 sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK); 673 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) { 674 sgsize = roundup2(sgsize, dmat->alignment); 675 sgsize = MIN(sgsize, max_sgsize); 676 curaddr = add_bounce_page(dmat, map, vaddr, sgsize); 677 } else { 678 sgsize = MIN(sgsize, max_sgsize); 679 } 680 681 /* 682 * Make sure we don't cross any boundaries. 683 */ 684 if (dmat->boundary > 0) { 685 baddr = (curaddr + dmat->boundary) & bmask; 686 if (sgsize > (baddr - curaddr)) 687 sgsize = (baddr - curaddr); 688 } 689 690 /* 691 * Insert chunk into a segment, coalescing with 692 * previous segment if possible. 693 */ 694 if (first) { 695 segs[seg].ds_addr = curaddr; 696 segs[seg].ds_len = sgsize; 697 first = 0; 698 } else { 699 if (curaddr == lastaddr && 700 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz && 701 (dmat->boundary == 0 || 702 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 703 segs[seg].ds_len += sgsize; 704 else { 705 if (++seg >= dmat->nsegments) 706 break; 707 segs[seg].ds_addr = curaddr; 708 segs[seg].ds_len = sgsize; 709 } 710 } 711 712 lastaddr = curaddr + sgsize; 713 vaddr += sgsize; 714 buflen -= sgsize; 715 } 716 717 *segp = seg; 718 *lastaddrp = lastaddr; 719 720 /* 721 * Did we fit? 722 */ 723 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 724 } 725 726 /* 727 * Map the buffer buf into bus space using the dmamap map. 728 */ 729 int 730 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 731 bus_size_t buflen, bus_dmamap_callback_t *callback, 732 void *callback_arg, int flags) 733 { 734 bus_addr_t lastaddr = 0; 735 int error, nsegs = 0; 736 737 if (map != NULL) { 738 flags |= BUS_DMA_WAITOK; 739 map->callback = callback; 740 map->callback_arg = callback_arg; 741 } 742 743 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags, 744 &lastaddr, dmat->segments, &nsegs, 1); 745 746 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 747 __func__, dmat, dmat->flags, error, nsegs + 1); 748 749 if (error == EINPROGRESS) { 750 return (error); 751 } 752 753 if (error) 754 (*callback)(callback_arg, dmat->segments, 0, error); 755 else 756 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0); 757 758 /* 759 * Return ENOMEM to the caller so that it can pass it up the stack. 760 * This error only happens when NOWAIT is set, so deferal is disabled. 761 */ 762 if (error == ENOMEM) 763 return (error); 764 765 return (0); 766 } 767 768 769 /* 770 * Like _bus_dmamap_load(), but for mbufs. 771 */ 772 int 773 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 774 struct mbuf *m0, 775 bus_dmamap_callback2_t *callback, void *callback_arg, 776 int flags) 777 { 778 int nsegs, error; 779 780 M_ASSERTPKTHDR(m0); 781 782 flags |= BUS_DMA_NOWAIT; 783 nsegs = 0; 784 error = 0; 785 if (m0->m_pkthdr.len <= dmat->maxsize) { 786 int first = 1; 787 bus_addr_t lastaddr = 0; 788 struct mbuf *m; 789 790 for (m = m0; m != NULL && error == 0; m = m->m_next) { 791 if (m->m_len > 0) { 792 error = _bus_dmamap_load_buffer(dmat, map, 793 m->m_data, m->m_len, 794 NULL, flags, &lastaddr, 795 dmat->segments, &nsegs, first); 796 first = 0; 797 } 798 } 799 } else { 800 error = EINVAL; 801 } 802 803 if (error) { 804 /* force "no valid mappings" in callback */ 805 (*callback)(callback_arg, dmat->segments, 0, 0, error); 806 } else { 807 (*callback)(callback_arg, dmat->segments, 808 nsegs+1, m0->m_pkthdr.len, error); 809 } 810 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 811 __func__, dmat, dmat->flags, error, nsegs + 1); 812 return (error); 813 } 814 815 int 816 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, 817 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, 818 int flags) 819 { 820 int error; 821 822 M_ASSERTPKTHDR(m0); 823 824 flags |= BUS_DMA_NOWAIT; 825 *nsegs = 0; 826 error = 0; 827 if (m0->m_pkthdr.len <= dmat->maxsize) { 828 int first = 1; 829 bus_addr_t lastaddr = 0; 830 struct mbuf *m; 831 832 for (m = m0; m != NULL && error == 0; m = m->m_next) { 833 if (m->m_len > 0) { 834 error = _bus_dmamap_load_buffer(dmat, map, 835 m->m_data, m->m_len, 836 NULL, flags, &lastaddr, 837 segs, nsegs, first); 838 first = 0; 839 } 840 } 841 } else { 842 error = EINVAL; 843 } 844 845 /* XXX FIXME: Having to increment nsegs is really annoying */ 846 ++*nsegs; 847 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 848 __func__, dmat, dmat->flags, error, *nsegs); 849 return (error); 850 } 851 852 /* 853 * Like _bus_dmamap_load(), but for uios. 854 */ 855 int 856 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 857 struct uio *uio, 858 bus_dmamap_callback2_t *callback, void *callback_arg, 859 int flags) 860 { 861 bus_addr_t lastaddr = 0; 862 int nsegs, error, first, i; 863 bus_size_t resid; 864 struct iovec *iov; 865 pmap_t pmap; 866 867 flags |= BUS_DMA_NOWAIT; 868 resid = uio->uio_resid; 869 iov = uio->uio_iov; 870 871 if (uio->uio_segflg == UIO_USERSPACE) { 872 KASSERT(uio->uio_td != NULL, 873 ("bus_dmamap_load_uio: USERSPACE but no proc")); 874 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace); 875 } else 876 pmap = NULL; 877 878 nsegs = 0; 879 error = 0; 880 first = 1; 881 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 882 /* 883 * Now at the first iovec to load. Load each iovec 884 * until we have exhausted the residual count. 885 */ 886 bus_size_t minlen = 887 resid < iov[i].iov_len ? resid : iov[i].iov_len; 888 caddr_t addr = (caddr_t) iov[i].iov_base; 889 890 if (minlen > 0) { 891 error = _bus_dmamap_load_buffer(dmat, map, 892 addr, minlen, pmap, flags, &lastaddr, 893 dmat->segments, &nsegs, first); 894 first = 0; 895 896 resid -= minlen; 897 } 898 } 899 900 if (error) { 901 /* force "no valid mappings" in callback */ 902 (*callback)(callback_arg, dmat->segments, 0, 0, error); 903 } else { 904 (*callback)(callback_arg, dmat->segments, 905 nsegs+1, uio->uio_resid, error); 906 } 907 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 908 __func__, dmat, dmat->flags, error, nsegs + 1); 909 return (error); 910 } 911 912 /* 913 * Release the mapping held by map. 914 */ 915 void 916 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 917 { 918 struct bounce_page *bpage; 919 920 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 921 STAILQ_REMOVE_HEAD(&map->bpages, links); 922 free_bounce_page(dmat, bpage); 923 } 924 } 925 926 void 927 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 928 { 929 struct bounce_page *bpage; 930 931 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 932 /* 933 * Handle data bouncing. We might also 934 * want to add support for invalidating 935 * the caches on broken hardware 936 */ 937 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 938 "performing bounce", __func__, op, dmat, dmat->flags); 939 940 if (op & BUS_DMASYNC_PREWRITE) { 941 while (bpage != NULL) { 942 bcopy((void *)bpage->datavaddr, 943 (void *)bpage->vaddr, 944 bpage->datacount); 945 bpage = STAILQ_NEXT(bpage, links); 946 } 947 dmat->bounce_zone->total_bounced++; 948 } 949 950 if (op & BUS_DMASYNC_POSTREAD) { 951 while (bpage != NULL) { 952 bcopy((void *)bpage->vaddr, 953 (void *)bpage->datavaddr, 954 bpage->datacount); 955 bpage = STAILQ_NEXT(bpage, links); 956 } 957 dmat->bounce_zone->total_bounced++; 958 } 959 } 960 } 961 962 static void 963 init_bounce_pages(void *dummy __unused) 964 { 965 966 total_bpages = 0; 967 STAILQ_INIT(&bounce_zone_list); 968 STAILQ_INIT(&bounce_map_waitinglist); 969 STAILQ_INIT(&bounce_map_callbacklist); 970 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 971 } 972 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 973 974 static struct sysctl_ctx_list * 975 busdma_sysctl_tree(struct bounce_zone *bz) 976 { 977 return (&bz->sysctl_tree); 978 } 979 980 static struct sysctl_oid * 981 busdma_sysctl_tree_top(struct bounce_zone *bz) 982 { 983 return (bz->sysctl_tree_top); 984 } 985 986 static int 987 alloc_bounce_zone(bus_dma_tag_t dmat) 988 { 989 struct bounce_zone *bz; 990 991 /* Check to see if we already have a suitable zone */ 992 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 993 if ((dmat->alignment <= bz->alignment) 994 && (dmat->lowaddr >= bz->lowaddr)) { 995 dmat->bounce_zone = bz; 996 return (0); 997 } 998 } 999 1000 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 1001 M_NOWAIT | M_ZERO)) == NULL) 1002 return (ENOMEM); 1003 1004 STAILQ_INIT(&bz->bounce_page_list); 1005 bz->free_bpages = 0; 1006 bz->reserved_bpages = 0; 1007 bz->active_bpages = 0; 1008 bz->lowaddr = dmat->lowaddr; 1009 bz->alignment = MAX(dmat->alignment, PAGE_SIZE); 1010 bz->map_count = 0; 1011 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 1012 busdma_zonecount++; 1013 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 1014 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 1015 dmat->bounce_zone = bz; 1016 1017 sysctl_ctx_init(&bz->sysctl_tree); 1018 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 1019 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1020 CTLFLAG_RD, 0, ""); 1021 if (bz->sysctl_tree_top == NULL) { 1022 sysctl_ctx_free(&bz->sysctl_tree); 1023 return (0); /* XXX error code? */ 1024 } 1025 1026 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1027 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1028 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1029 "Total bounce pages"); 1030 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1031 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1032 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1033 "Free bounce pages"); 1034 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1035 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1036 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1037 "Reserved bounce pages"); 1038 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1039 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1040 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1041 "Active bounce pages"); 1042 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1043 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1044 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1045 "Total bounce requests"); 1046 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1047 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1048 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1049 "Total bounce requests that were deferred"); 1050 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1051 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1052 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1053 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1054 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1055 "alignment", CTLFLAG_RD, &bz->alignment, 0, ""); 1056 1057 return (0); 1058 } 1059 1060 static int 1061 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1062 { 1063 struct bounce_zone *bz; 1064 int count; 1065 1066 bz = dmat->bounce_zone; 1067 count = 0; 1068 while (numpages > 0) { 1069 struct bounce_page *bpage; 1070 1071 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 1072 M_NOWAIT | M_ZERO); 1073 1074 if (bpage == NULL) 1075 break; 1076 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1077 M_NOWAIT, 0ul, 1078 bz->lowaddr, 1079 PAGE_SIZE, 1080 0); 1081 if (bpage->vaddr == 0) { 1082 free(bpage, M_DEVBUF); 1083 break; 1084 } 1085 bpage->busaddr = pmap_kextract(bpage->vaddr); 1086 mtx_lock(&bounce_lock); 1087 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1088 total_bpages++; 1089 bz->total_bpages++; 1090 bz->free_bpages++; 1091 mtx_unlock(&bounce_lock); 1092 count++; 1093 numpages--; 1094 } 1095 return (count); 1096 } 1097 1098 static int 1099 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1100 { 1101 struct bounce_zone *bz; 1102 int pages; 1103 1104 mtx_assert(&bounce_lock, MA_OWNED); 1105 bz = dmat->bounce_zone; 1106 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1107 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1108 return (map->pagesneeded - (map->pagesreserved + pages)); 1109 bz->free_bpages -= pages; 1110 bz->reserved_bpages += pages; 1111 map->pagesreserved += pages; 1112 pages = map->pagesneeded - map->pagesreserved; 1113 1114 return (pages); 1115 } 1116 1117 static bus_addr_t 1118 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1119 bus_size_t size) 1120 { 1121 struct bounce_zone *bz; 1122 struct bounce_page *bpage; 1123 1124 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1125 KASSERT(map != NULL && map != &nobounce_dmamap, 1126 ("add_bounce_page: bad map %p", map)); 1127 1128 bz = dmat->bounce_zone; 1129 if (map->pagesneeded == 0) 1130 panic("add_bounce_page: map doesn't need any pages"); 1131 map->pagesneeded--; 1132 1133 if (map->pagesreserved == 0) 1134 panic("add_bounce_page: map doesn't need any pages"); 1135 map->pagesreserved--; 1136 1137 mtx_lock(&bounce_lock); 1138 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1139 if (bpage == NULL) 1140 panic("add_bounce_page: free page list is empty"); 1141 1142 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1143 bz->reserved_bpages--; 1144 bz->active_bpages++; 1145 mtx_unlock(&bounce_lock); 1146 1147 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) { 1148 /* Page offset needs to be preserved. */ 1149 bpage->vaddr |= vaddr & PAGE_MASK; 1150 bpage->busaddr |= vaddr & PAGE_MASK; 1151 } 1152 bpage->datavaddr = vaddr; 1153 bpage->datacount = size; 1154 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1155 return (bpage->busaddr); 1156 } 1157 1158 static void 1159 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1160 { 1161 struct bus_dmamap *map; 1162 struct bounce_zone *bz; 1163 1164 bz = dmat->bounce_zone; 1165 bpage->datavaddr = 0; 1166 bpage->datacount = 0; 1167 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) { 1168 /* 1169 * Reset the bounce page to start at offset 0. Other uses 1170 * of this bounce page may need to store a full page of 1171 * data and/or assume it starts on a page boundary. 1172 */ 1173 bpage->vaddr &= ~PAGE_MASK; 1174 bpage->busaddr &= ~PAGE_MASK; 1175 } 1176 1177 mtx_lock(&bounce_lock); 1178 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1179 bz->free_bpages++; 1180 bz->active_bpages--; 1181 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1182 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1183 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1184 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1185 map, links); 1186 busdma_swi_pending = 1; 1187 bz->total_deferred++; 1188 swi_sched(vm_ih, 0); 1189 } 1190 } 1191 mtx_unlock(&bounce_lock); 1192 } 1193 1194 void 1195 busdma_swi(void) 1196 { 1197 bus_dma_tag_t dmat; 1198 struct bus_dmamap *map; 1199 1200 mtx_lock(&bounce_lock); 1201 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1202 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1203 mtx_unlock(&bounce_lock); 1204 dmat = map->dmat; 1205 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK); 1206 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1207 map->callback, map->callback_arg, /*flags*/0); 1208 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK); 1209 mtx_lock(&bounce_lock); 1210 } 1211 mtx_unlock(&bounce_lock); 1212 } 1213