1 /*- 2 * Copyright (c) 1997, 1998 Justin T. Gibbs. 3 * Copyright (c) 2015-2016 The FreeBSD Foundation 4 * All rights reserved. 5 * 6 * Portions of this software were developed by Andrew Turner 7 * under sponsorship of the FreeBSD Foundation. 8 * 9 * Portions of this software were developed by Semihalf 10 * under sponsorship of the FreeBSD Foundation. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions, and the following disclaimer, 17 * without modification, immediately at the beginning of the file. 18 * 2. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR 25 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/malloc.h> 40 #include <sys/bus.h> 41 #include <sys/interrupt.h> 42 #include <sys/kernel.h> 43 #include <sys/ktr.h> 44 #include <sys/lock.h> 45 #include <sys/proc.h> 46 #include <sys/memdesc.h> 47 #include <sys/mutex.h> 48 #include <sys/sysctl.h> 49 #include <sys/uio.h> 50 51 #include <vm/vm.h> 52 #include <vm/vm_extern.h> 53 #include <vm/vm_kern.h> 54 #include <vm/vm_page.h> 55 #include <vm/vm_map.h> 56 57 #include <machine/atomic.h> 58 #include <machine/bus.h> 59 #include <machine/md_var.h> 60 #include <arm64/include/bus_dma_impl.h> 61 62 #define MAX_BPAGES 4096 63 64 enum { 65 BF_COULD_BOUNCE = 0x01, 66 BF_MIN_ALLOC_COMP = 0x02, 67 BF_KMEM_ALLOC = 0x04, 68 BF_COHERENT = 0x10, 69 }; 70 71 struct bounce_zone; 72 73 struct bus_dma_tag { 74 struct bus_dma_tag_common common; 75 int map_count; 76 int bounce_flags; 77 bus_dma_segment_t *segments; 78 struct bounce_zone *bounce_zone; 79 }; 80 81 struct bounce_page { 82 vm_offset_t vaddr; /* kva of bounce buffer */ 83 bus_addr_t busaddr; /* Physical address */ 84 vm_offset_t datavaddr; /* kva of client data */ 85 vm_page_t datapage; /* physical page of client data */ 86 vm_offset_t dataoffs; /* page offset of client data */ 87 bus_size_t datacount; /* client data count */ 88 STAILQ_ENTRY(bounce_page) links; 89 }; 90 91 int busdma_swi_pending; 92 93 struct bounce_zone { 94 STAILQ_ENTRY(bounce_zone) links; 95 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 96 int total_bpages; 97 int free_bpages; 98 int reserved_bpages; 99 int active_bpages; 100 int total_bounced; 101 int total_deferred; 102 int map_count; 103 bus_size_t alignment; 104 bus_addr_t lowaddr; 105 char zoneid[8]; 106 char lowaddrid[20]; 107 struct sysctl_ctx_list sysctl_tree; 108 struct sysctl_oid *sysctl_tree_top; 109 }; 110 111 static struct mtx bounce_lock; 112 static int total_bpages; 113 static int busdma_zonecount; 114 static STAILQ_HEAD(, bounce_zone) bounce_zone_list; 115 116 static SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 117 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 118 "Total bounce pages"); 119 120 struct sync_list { 121 vm_offset_t vaddr; /* kva of client data */ 122 bus_addr_t paddr; /* physical address */ 123 vm_page_t pages; /* starting page of client data */ 124 bus_size_t datacount; /* client data count */ 125 }; 126 127 struct bus_dmamap { 128 struct bp_list bpages; 129 int pagesneeded; 130 int pagesreserved; 131 bus_dma_tag_t dmat; 132 struct memdesc mem; 133 bus_dmamap_callback_t *callback; 134 void *callback_arg; 135 STAILQ_ENTRY(bus_dmamap) links; 136 u_int flags; 137 #define DMAMAP_COULD_BOUNCE (1 << 0) 138 #define DMAMAP_FROM_DMAMEM (1 << 1) 139 int sync_count; 140 struct sync_list slist[]; 141 }; 142 143 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 144 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 145 146 static void init_bounce_pages(void *dummy); 147 static int alloc_bounce_zone(bus_dma_tag_t dmat); 148 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 149 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 150 int commit); 151 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 152 vm_offset_t vaddr, bus_addr_t addr, bus_size_t size); 153 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 154 int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr); 155 static void _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 156 pmap_t pmap, void *buf, bus_size_t buflen, int flags); 157 static void _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, 158 vm_paddr_t buf, bus_size_t buflen, int flags); 159 static int _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 160 int flags); 161 162 /* 163 * Allocate a device specific dma_tag. 164 */ 165 static int 166 bounce_bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 167 bus_addr_t boundary, bus_addr_t lowaddr, bus_addr_t highaddr, 168 bus_dma_filter_t *filter, void *filterarg, bus_size_t maxsize, 169 int nsegments, bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 170 void *lockfuncarg, bus_dma_tag_t *dmat) 171 { 172 bus_dma_tag_t newtag; 173 int error; 174 175 *dmat = NULL; 176 error = common_bus_dma_tag_create(parent != NULL ? &parent->common : 177 NULL, alignment, boundary, lowaddr, highaddr, filter, filterarg, 178 maxsize, nsegments, maxsegsz, flags, lockfunc, lockfuncarg, 179 sizeof (struct bus_dma_tag), (void **)&newtag); 180 if (error != 0) 181 return (error); 182 183 newtag->common.impl = &bus_dma_bounce_impl; 184 newtag->map_count = 0; 185 newtag->segments = NULL; 186 187 if ((flags & BUS_DMA_COHERENT) != 0) 188 newtag->bounce_flags |= BF_COHERENT; 189 190 if (parent != NULL) { 191 if ((newtag->common.filter != NULL || 192 (parent->bounce_flags & BF_COULD_BOUNCE) != 0)) 193 newtag->bounce_flags |= BF_COULD_BOUNCE; 194 195 /* Copy some flags from the parent */ 196 newtag->bounce_flags |= parent->bounce_flags & BF_COHERENT; 197 } 198 199 if (newtag->common.lowaddr < ptoa((vm_paddr_t)Maxmem) || 200 newtag->common.alignment > 1) 201 newtag->bounce_flags |= BF_COULD_BOUNCE; 202 203 if (((newtag->bounce_flags & BF_COULD_BOUNCE) != 0) && 204 (flags & BUS_DMA_ALLOCNOW) != 0) { 205 struct bounce_zone *bz; 206 207 /* Must bounce */ 208 if ((error = alloc_bounce_zone(newtag)) != 0) { 209 free(newtag, M_DEVBUF); 210 return (error); 211 } 212 bz = newtag->bounce_zone; 213 214 if (ptoa(bz->total_bpages) < maxsize) { 215 int pages; 216 217 pages = atop(maxsize) - bz->total_bpages; 218 219 /* Add pages to our bounce pool */ 220 if (alloc_bounce_pages(newtag, pages) < pages) 221 error = ENOMEM; 222 } 223 /* Performed initial allocation */ 224 newtag->bounce_flags |= BF_MIN_ALLOC_COMP; 225 } else 226 error = 0; 227 228 if (error != 0) 229 free(newtag, M_DEVBUF); 230 else 231 *dmat = newtag; 232 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 233 __func__, newtag, (newtag != NULL ? newtag->common.flags : 0), 234 error); 235 return (error); 236 } 237 238 static int 239 bounce_bus_dma_tag_destroy(bus_dma_tag_t dmat) 240 { 241 bus_dma_tag_t dmat_copy, parent; 242 int error; 243 244 error = 0; 245 dmat_copy = dmat; 246 247 if (dmat != NULL) { 248 if (dmat->map_count != 0) { 249 error = EBUSY; 250 goto out; 251 } 252 while (dmat != NULL) { 253 parent = (bus_dma_tag_t)dmat->common.parent; 254 atomic_subtract_int(&dmat->common.ref_count, 1); 255 if (dmat->common.ref_count == 0) { 256 if (dmat->segments != NULL) 257 free(dmat->segments, M_DEVBUF); 258 free(dmat, M_DEVBUF); 259 /* 260 * Last reference count, so 261 * release our reference 262 * count on our parent. 263 */ 264 dmat = parent; 265 } else 266 dmat = NULL; 267 } 268 } 269 out: 270 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 271 return (error); 272 } 273 274 static bus_dmamap_t 275 alloc_dmamap(bus_dma_tag_t dmat, int flags) 276 { 277 u_long mapsize; 278 bus_dmamap_t map; 279 280 mapsize = sizeof(*map); 281 mapsize += sizeof(struct sync_list) * dmat->common.nsegments; 282 map = malloc(mapsize, M_DEVBUF, flags | M_ZERO); 283 if (map == NULL) 284 return (NULL); 285 286 /* Initialize the new map */ 287 STAILQ_INIT(&map->bpages); 288 289 return (map); 290 } 291 292 /* 293 * Allocate a handle for mapping from kva/uva/physical 294 * address space into bus device space. 295 */ 296 static int 297 bounce_bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 298 { 299 struct bounce_zone *bz; 300 int error, maxpages, pages; 301 302 error = 0; 303 304 if (dmat->segments == NULL) { 305 dmat->segments = (bus_dma_segment_t *)malloc( 306 sizeof(bus_dma_segment_t) * dmat->common.nsegments, 307 M_DEVBUF, M_NOWAIT); 308 if (dmat->segments == NULL) { 309 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 310 __func__, dmat, ENOMEM); 311 return (ENOMEM); 312 } 313 } 314 315 *mapp = alloc_dmamap(dmat, M_NOWAIT); 316 if (*mapp == NULL) { 317 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 318 __func__, dmat, ENOMEM); 319 return (ENOMEM); 320 } 321 322 /* 323 * Bouncing might be required if the driver asks for an active 324 * exclusion region, a data alignment that is stricter than 1, and/or 325 * an active address boundary. 326 */ 327 if (dmat->bounce_flags & BF_COULD_BOUNCE) { 328 /* Must bounce */ 329 if (dmat->bounce_zone == NULL) { 330 if ((error = alloc_bounce_zone(dmat)) != 0) { 331 free(*mapp, M_DEVBUF); 332 return (error); 333 } 334 } 335 bz = dmat->bounce_zone; 336 337 (*mapp)->flags = DMAMAP_COULD_BOUNCE; 338 339 /* 340 * Attempt to add pages to our pool on a per-instance 341 * basis up to a sane limit. 342 */ 343 if (dmat->common.alignment > 1) 344 maxpages = MAX_BPAGES; 345 else 346 maxpages = MIN(MAX_BPAGES, Maxmem - 347 atop(dmat->common.lowaddr)); 348 if ((dmat->bounce_flags & BF_MIN_ALLOC_COMP) == 0 || 349 (bz->map_count > 0 && bz->total_bpages < maxpages)) { 350 pages = MAX(atop(dmat->common.maxsize), 1); 351 pages = MIN(maxpages - bz->total_bpages, pages); 352 pages = MAX(pages, 1); 353 if (alloc_bounce_pages(dmat, pages) < pages) 354 error = ENOMEM; 355 if ((dmat->bounce_flags & BF_MIN_ALLOC_COMP) 356 == 0) { 357 if (error == 0) { 358 dmat->bounce_flags |= 359 BF_MIN_ALLOC_COMP; 360 } 361 } else 362 error = 0; 363 } 364 bz->map_count++; 365 } 366 if (error == 0) 367 dmat->map_count++; 368 else 369 free(*mapp, M_DEVBUF); 370 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 371 __func__, dmat, dmat->common.flags, error); 372 return (error); 373 } 374 375 /* 376 * Destroy a handle for mapping from kva/uva/physical 377 * address space into bus device space. 378 */ 379 static int 380 bounce_bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 381 { 382 383 /* Check we are destroying the correct map type */ 384 if ((map->flags & DMAMAP_FROM_DMAMEM) != 0) 385 panic("bounce_bus_dmamap_destroy: Invalid map freed\n"); 386 387 if (STAILQ_FIRST(&map->bpages) != NULL || map->sync_count != 0) { 388 CTR3(KTR_BUSDMA, "%s: tag %p error %d", __func__, dmat, EBUSY); 389 return (EBUSY); 390 } 391 if (dmat->bounce_zone) { 392 KASSERT((map->flags & DMAMAP_COULD_BOUNCE) != 0, 393 ("%s: Bounce zone when cannot bounce", __func__)); 394 dmat->bounce_zone->map_count--; 395 } 396 free(map, M_DEVBUF); 397 dmat->map_count--; 398 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 399 return (0); 400 } 401 402 403 /* 404 * Allocate a piece of memory that can be efficiently mapped into 405 * bus device space based on the constraints lited in the dma tag. 406 * A dmamap to for use with dmamap_load is also allocated. 407 */ 408 static int 409 bounce_bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 410 bus_dmamap_t *mapp) 411 { 412 /* 413 * XXX ARM64TODO: 414 * This bus_dma implementation requires IO-Coherent architecutre. 415 * If IO-Coherency is not guaranteed, the BUS_DMA_COHERENT flag has 416 * to be implented using non-cacheable memory. 417 */ 418 419 vm_memattr_t attr; 420 int mflags; 421 422 if (flags & BUS_DMA_NOWAIT) 423 mflags = M_NOWAIT; 424 else 425 mflags = M_WAITOK; 426 427 if (dmat->segments == NULL) { 428 dmat->segments = (bus_dma_segment_t *)malloc( 429 sizeof(bus_dma_segment_t) * dmat->common.nsegments, 430 M_DEVBUF, mflags); 431 if (dmat->segments == NULL) { 432 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 433 __func__, dmat, dmat->common.flags, ENOMEM); 434 return (ENOMEM); 435 } 436 } 437 if (flags & BUS_DMA_ZERO) 438 mflags |= M_ZERO; 439 if (flags & BUS_DMA_NOCACHE) 440 attr = VM_MEMATTR_UNCACHEABLE; 441 else if ((flags & BUS_DMA_COHERENT) != 0 && 442 (dmat->bounce_flags & BF_COHERENT) == 0) 443 /* 444 * If we have a non-coherent tag, and are trying to allocate 445 * a coherent block of memory it needs to be uncached. 446 */ 447 attr = VM_MEMATTR_UNCACHEABLE; 448 else 449 attr = VM_MEMATTR_DEFAULT; 450 451 /* 452 * Create the map, but don't set the could bounce flag as 453 * this allocation should never bounce; 454 */ 455 *mapp = alloc_dmamap(dmat, mflags); 456 if (*mapp == NULL) { 457 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 458 __func__, dmat, dmat->common.flags, ENOMEM); 459 return (ENOMEM); 460 } 461 (*mapp)->flags = DMAMAP_FROM_DMAMEM; 462 463 /* 464 * XXX: 465 * (dmat->alignment <= dmat->maxsize) is just a quick hack; the exact 466 * alignment guarantees of malloc need to be nailed down, and the 467 * code below should be rewritten to take that into account. 468 * 469 * In the meantime, we'll warn the user if malloc gets it wrong. 470 */ 471 if ((dmat->common.maxsize <= PAGE_SIZE) && 472 (dmat->common.alignment <= dmat->common.maxsize) && 473 dmat->common.lowaddr >= ptoa((vm_paddr_t)Maxmem) && 474 attr == VM_MEMATTR_DEFAULT) { 475 *vaddr = malloc(dmat->common.maxsize, M_DEVBUF, mflags); 476 } else if (dmat->common.nsegments >= btoc(dmat->common.maxsize) && 477 dmat->common.alignment <= PAGE_SIZE && 478 (dmat->common.boundary == 0 || 479 dmat->common.boundary >= dmat->common.lowaddr)) { 480 /* Page-based multi-segment allocations allowed */ 481 *vaddr = (void *)kmem_alloc_attr(kernel_arena, 482 dmat->common.maxsize, mflags, 0ul, dmat->common.lowaddr, 483 attr); 484 dmat->bounce_flags |= BF_KMEM_ALLOC; 485 } else { 486 *vaddr = (void *)kmem_alloc_contig(kernel_arena, 487 dmat->common.maxsize, mflags, 0ul, dmat->common.lowaddr, 488 dmat->common.alignment != 0 ? dmat->common.alignment : 1ul, 489 dmat->common.boundary, attr); 490 dmat->bounce_flags |= BF_KMEM_ALLOC; 491 } 492 if (*vaddr == NULL) { 493 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 494 __func__, dmat, dmat->common.flags, ENOMEM); 495 free(*mapp, M_DEVBUF); 496 return (ENOMEM); 497 } else if (vtophys(*vaddr) & (dmat->common.alignment - 1)) { 498 printf("bus_dmamem_alloc failed to align memory properly.\n"); 499 } 500 dmat->map_count++; 501 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 502 __func__, dmat, dmat->common.flags, 0); 503 return (0); 504 } 505 506 /* 507 * Free a piece of memory and it's allociated dmamap, that was allocated 508 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 509 */ 510 static void 511 bounce_bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 512 { 513 514 /* 515 * Check the map came from bounce_bus_dmamem_alloc, so the map 516 * should be NULL and the BF_KMEM_ALLOC flag cleared if malloc() 517 * was used and set if kmem_alloc_contig() was used. 518 */ 519 if ((map->flags & DMAMAP_FROM_DMAMEM) == 0) 520 panic("bus_dmamem_free: Invalid map freed\n"); 521 if ((dmat->bounce_flags & BF_KMEM_ALLOC) == 0) 522 free(vaddr, M_DEVBUF); 523 else 524 kmem_free(kernel_arena, (vm_offset_t)vaddr, 525 dmat->common.maxsize); 526 free(map, M_DEVBUF); 527 dmat->map_count--; 528 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, 529 dmat->bounce_flags); 530 } 531 532 static void 533 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf, 534 bus_size_t buflen, int flags) 535 { 536 bus_addr_t curaddr; 537 bus_size_t sgsize; 538 539 if ((map->flags & DMAMAP_COULD_BOUNCE) != 0 && map->pagesneeded == 0) { 540 /* 541 * Count the number of bounce pages 542 * needed in order to complete this transfer 543 */ 544 curaddr = buf; 545 while (buflen != 0) { 546 sgsize = MIN(buflen, dmat->common.maxsegsz); 547 if (bus_dma_run_filter(&dmat->common, curaddr)) { 548 sgsize = MIN(sgsize, 549 PAGE_SIZE - (curaddr & PAGE_MASK)); 550 map->pagesneeded++; 551 } 552 curaddr += sgsize; 553 buflen -= sgsize; 554 } 555 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 556 } 557 } 558 559 static void 560 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap, 561 void *buf, bus_size_t buflen, int flags) 562 { 563 vm_offset_t vaddr; 564 vm_offset_t vendaddr; 565 bus_addr_t paddr; 566 bus_size_t sg_len; 567 568 if ((map->flags & DMAMAP_COULD_BOUNCE) != 0 && map->pagesneeded == 0) { 569 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 570 "alignment= %d", dmat->common.lowaddr, 571 ptoa((vm_paddr_t)Maxmem), 572 dmat->common.boundary, dmat->common.alignment); 573 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map, 574 map->pagesneeded); 575 /* 576 * Count the number of bounce pages 577 * needed in order to complete this transfer 578 */ 579 vaddr = (vm_offset_t)buf; 580 vendaddr = (vm_offset_t)buf + buflen; 581 582 while (vaddr < vendaddr) { 583 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK); 584 if (pmap == kernel_pmap) 585 paddr = pmap_kextract(vaddr); 586 else 587 paddr = pmap_extract(pmap, vaddr); 588 if (bus_dma_run_filter(&dmat->common, paddr) != 0) { 589 sg_len = roundup2(sg_len, 590 dmat->common.alignment); 591 map->pagesneeded++; 592 } 593 vaddr += sg_len; 594 } 595 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 596 } 597 } 598 599 static int 600 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags) 601 { 602 603 /* Reserve Necessary Bounce Pages */ 604 mtx_lock(&bounce_lock); 605 if (flags & BUS_DMA_NOWAIT) { 606 if (reserve_bounce_pages(dmat, map, 0) != 0) { 607 mtx_unlock(&bounce_lock); 608 return (ENOMEM); 609 } 610 } else { 611 if (reserve_bounce_pages(dmat, map, 1) != 0) { 612 /* Queue us for resources */ 613 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, map, links); 614 mtx_unlock(&bounce_lock); 615 return (EINPROGRESS); 616 } 617 } 618 mtx_unlock(&bounce_lock); 619 620 return (0); 621 } 622 623 /* 624 * Add a single contiguous physical range to the segment list. 625 */ 626 static int 627 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, bus_addr_t curaddr, 628 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp) 629 { 630 bus_addr_t baddr, bmask; 631 int seg; 632 633 /* 634 * Make sure we don't cross any boundaries. 635 */ 636 bmask = ~(dmat->common.boundary - 1); 637 if (dmat->common.boundary > 0) { 638 baddr = (curaddr + dmat->common.boundary) & bmask; 639 if (sgsize > (baddr - curaddr)) 640 sgsize = (baddr - curaddr); 641 } 642 643 /* 644 * Insert chunk into a segment, coalescing with 645 * previous segment if possible. 646 */ 647 seg = *segp; 648 if (seg == -1) { 649 seg = 0; 650 segs[seg].ds_addr = curaddr; 651 segs[seg].ds_len = sgsize; 652 } else { 653 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len && 654 (segs[seg].ds_len + sgsize) <= dmat->common.maxsegsz && 655 (dmat->common.boundary == 0 || 656 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 657 segs[seg].ds_len += sgsize; 658 else { 659 if (++seg >= dmat->common.nsegments) 660 return (0); 661 segs[seg].ds_addr = curaddr; 662 segs[seg].ds_len = sgsize; 663 } 664 } 665 *segp = seg; 666 return (sgsize); 667 } 668 669 /* 670 * Utility function to load a physical buffer. segp contains 671 * the starting segment on entrace, and the ending segment on exit. 672 */ 673 static int 674 bounce_bus_dmamap_load_phys(bus_dma_tag_t dmat, bus_dmamap_t map, 675 vm_paddr_t buf, bus_size_t buflen, int flags, bus_dma_segment_t *segs, 676 int *segp) 677 { 678 struct sync_list *sl; 679 bus_size_t sgsize; 680 bus_addr_t curaddr, sl_end; 681 int error; 682 683 if (segs == NULL) 684 segs = dmat->segments; 685 686 if ((dmat->bounce_flags & BF_COULD_BOUNCE) != 0) { 687 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags); 688 if (map->pagesneeded != 0) { 689 error = _bus_dmamap_reserve_pages(dmat, map, flags); 690 if (error) 691 return (error); 692 } 693 } 694 695 sl = map->slist + map->sync_count - 1; 696 sl_end = 0; 697 698 while (buflen > 0) { 699 curaddr = buf; 700 sgsize = MIN(buflen, dmat->common.maxsegsz); 701 if (((dmat->bounce_flags & BF_COULD_BOUNCE) != 0) && 702 map->pagesneeded != 0 && 703 bus_dma_run_filter(&dmat->common, curaddr)) { 704 sgsize = MIN(sgsize, PAGE_SIZE - (curaddr & PAGE_MASK)); 705 curaddr = add_bounce_page(dmat, map, 0, curaddr, 706 sgsize); 707 } else if ((dmat->bounce_flags & BF_COHERENT) == 0) { 708 if (map->sync_count > 0) 709 sl_end = sl->paddr + sl->datacount; 710 711 if (map->sync_count == 0 || curaddr != sl_end) { 712 if (++map->sync_count > dmat->common.nsegments) 713 break; 714 sl++; 715 sl->vaddr = 0; 716 sl->paddr = curaddr; 717 sl->datacount = sgsize; 718 sl->pages = PHYS_TO_VM_PAGE(curaddr); 719 KASSERT(sl->pages != NULL, 720 ("%s: page at PA:0x%08lx is not in " 721 "vm_page_array", __func__, curaddr)); 722 } else 723 sl->datacount += sgsize; 724 } 725 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs, 726 segp); 727 if (sgsize == 0) 728 break; 729 buf += sgsize; 730 buflen -= sgsize; 731 } 732 733 /* 734 * Did we fit? 735 */ 736 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 737 } 738 739 /* 740 * Utility function to load a linear buffer. segp contains 741 * the starting segment on entrace, and the ending segment on exit. 742 */ 743 static int 744 bounce_bus_dmamap_load_buffer(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 745 bus_size_t buflen, pmap_t pmap, int flags, bus_dma_segment_t *segs, 746 int *segp) 747 { 748 struct sync_list *sl; 749 bus_size_t sgsize, max_sgsize; 750 bus_addr_t curaddr, sl_pend; 751 vm_offset_t kvaddr, vaddr, sl_vend; 752 int error; 753 754 if (segs == NULL) 755 segs = dmat->segments; 756 757 if ((dmat->bounce_flags & BF_COULD_BOUNCE) != 0) { 758 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags); 759 if (map->pagesneeded != 0) { 760 error = _bus_dmamap_reserve_pages(dmat, map, flags); 761 if (error) 762 return (error); 763 } 764 } 765 766 sl = map->slist + map->sync_count - 1; 767 vaddr = (vm_offset_t)buf; 768 sl_pend = 0; 769 sl_vend = 0; 770 771 while (buflen > 0) { 772 /* 773 * Get the physical address for this segment. 774 */ 775 if (pmap == kernel_pmap) { 776 curaddr = pmap_kextract(vaddr); 777 kvaddr = vaddr; 778 } else { 779 curaddr = pmap_extract(pmap, vaddr); 780 kvaddr = 0; 781 } 782 783 /* 784 * Compute the segment size, and adjust counts. 785 */ 786 max_sgsize = MIN(buflen, dmat->common.maxsegsz); 787 sgsize = PAGE_SIZE - (curaddr & PAGE_MASK); 788 if (((dmat->bounce_flags & BF_COULD_BOUNCE) != 0) && 789 map->pagesneeded != 0 && 790 bus_dma_run_filter(&dmat->common, curaddr)) { 791 sgsize = roundup2(sgsize, dmat->common.alignment); 792 sgsize = MIN(sgsize, max_sgsize); 793 curaddr = add_bounce_page(dmat, map, kvaddr, curaddr, 794 sgsize); 795 } else if ((dmat->bounce_flags & BF_COHERENT) == 0) { 796 sgsize = MIN(sgsize, max_sgsize); 797 if (map->sync_count > 0) { 798 sl_pend = sl->paddr + sl->datacount; 799 sl_vend = sl->vaddr + sl->datacount; 800 } 801 802 if (map->sync_count == 0 || 803 (kvaddr != 0 && kvaddr != sl_vend) || 804 (curaddr != sl_pend)) { 805 806 if (++map->sync_count > dmat->common.nsegments) 807 goto cleanup; 808 sl++; 809 sl->vaddr = kvaddr; 810 sl->paddr = curaddr; 811 if (kvaddr != 0) { 812 sl->pages = NULL; 813 } else { 814 sl->pages = PHYS_TO_VM_PAGE(curaddr); 815 KASSERT(sl->pages != NULL, 816 ("%s: page at PA:0x%08lx is not " 817 "in vm_page_array", __func__, 818 curaddr)); 819 } 820 sl->datacount = sgsize; 821 } else 822 sl->datacount += sgsize; 823 } else { 824 sgsize = MIN(sgsize, max_sgsize); 825 } 826 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs, 827 segp); 828 if (sgsize == 0) 829 break; 830 vaddr += sgsize; 831 buflen -= sgsize; 832 } 833 834 cleanup: 835 /* 836 * Did we fit? 837 */ 838 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 839 } 840 841 static void 842 bounce_bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map, 843 struct memdesc *mem, bus_dmamap_callback_t *callback, void *callback_arg) 844 { 845 846 if ((map->flags & DMAMAP_COULD_BOUNCE) == 0) 847 return; 848 map->mem = *mem; 849 map->dmat = dmat; 850 map->callback = callback; 851 map->callback_arg = callback_arg; 852 } 853 854 static bus_dma_segment_t * 855 bounce_bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map, 856 bus_dma_segment_t *segs, int nsegs, int error) 857 { 858 859 if (segs == NULL) 860 segs = dmat->segments; 861 return (segs); 862 } 863 864 /* 865 * Release the mapping held by map. 866 */ 867 static void 868 bounce_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 869 { 870 struct bounce_page *bpage; 871 872 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 873 STAILQ_REMOVE_HEAD(&map->bpages, links); 874 free_bounce_page(dmat, bpage); 875 } 876 877 map->sync_count = 0; 878 } 879 880 static void 881 dma_preread_safe(vm_offset_t va, vm_size_t size) 882 { 883 /* 884 * Write back any partial cachelines immediately before and 885 * after the DMA region. 886 */ 887 if (va & (dcache_line_size - 1)) 888 cpu_dcache_wb_range(va, 1); 889 if ((va + size) & (dcache_line_size - 1)) 890 cpu_dcache_wb_range(va + size, 1); 891 892 cpu_dcache_inv_range(va, size); 893 } 894 895 static void 896 dma_dcache_sync(struct sync_list *sl, bus_dmasync_op_t op) 897 { 898 uint32_t len, offset; 899 vm_page_t m; 900 vm_paddr_t pa; 901 vm_offset_t va, tempva; 902 bus_size_t size; 903 904 offset = sl->paddr & PAGE_MASK; 905 m = sl->pages; 906 size = sl->datacount; 907 pa = sl->paddr; 908 909 for ( ; size != 0; size -= len, pa += len, offset = 0, ++m) { 910 tempva = 0; 911 if (sl->vaddr == 0) { 912 len = min(PAGE_SIZE - offset, size); 913 tempva = pmap_quick_enter_page(m); 914 va = tempva | offset; 915 KASSERT(pa == (VM_PAGE_TO_PHYS(m) | offset), 916 ("unexpected vm_page_t phys: 0x%16lx != 0x%16lx", 917 VM_PAGE_TO_PHYS(m) | offset, pa)); 918 } else { 919 len = sl->datacount; 920 va = sl->vaddr; 921 } 922 923 switch (op) { 924 case BUS_DMASYNC_PREWRITE: 925 case BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD: 926 cpu_dcache_wb_range(va, len); 927 break; 928 case BUS_DMASYNC_PREREAD: 929 /* 930 * An mbuf may start in the middle of a cacheline. There 931 * will be no cpu writes to the beginning of that line 932 * (which contains the mbuf header) while dma is in 933 * progress. Handle that case by doing a writeback of 934 * just the first cacheline before invalidating the 935 * overall buffer. Any mbuf in a chain may have this 936 * misalignment. Buffers which are not mbufs bounce if 937 * they are not aligned to a cacheline. 938 */ 939 dma_preread_safe(va, len); 940 break; 941 case BUS_DMASYNC_POSTREAD: 942 case BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE: 943 cpu_dcache_inv_range(va, len); 944 break; 945 default: 946 panic("unsupported combination of sync operations: " 947 "0x%08x\n", op); 948 } 949 950 if (tempva != 0) 951 pmap_quick_remove_page(tempva); 952 } 953 } 954 955 static void 956 bounce_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, 957 bus_dmasync_op_t op) 958 { 959 struct bounce_page *bpage; 960 struct sync_list *sl, *end; 961 vm_offset_t datavaddr, tempvaddr; 962 963 if (op == BUS_DMASYNC_POSTWRITE) 964 return; 965 966 if ((op & BUS_DMASYNC_POSTREAD) != 0) { 967 /* 968 * Wait for any DMA operations to complete before the bcopy. 969 */ 970 dsb(sy); 971 } 972 973 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 974 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 975 "performing bounce", __func__, dmat, dmat->common.flags, 976 op); 977 978 if ((op & BUS_DMASYNC_PREWRITE) != 0) { 979 while (bpage != NULL) { 980 tempvaddr = 0; 981 datavaddr = bpage->datavaddr; 982 if (datavaddr == 0) { 983 tempvaddr = pmap_quick_enter_page( 984 bpage->datapage); 985 datavaddr = tempvaddr | bpage->dataoffs; 986 } 987 988 bcopy((void *)datavaddr, 989 (void *)bpage->vaddr, bpage->datacount); 990 if (tempvaddr != 0) 991 pmap_quick_remove_page(tempvaddr); 992 if ((dmat->bounce_flags & BF_COHERENT) == 0) 993 cpu_dcache_wb_range(bpage->vaddr, 994 bpage->datacount); 995 bpage = STAILQ_NEXT(bpage, links); 996 } 997 dmat->bounce_zone->total_bounced++; 998 } else if ((op & BUS_DMASYNC_PREREAD) != 0) { 999 while (bpage != NULL) { 1000 if ((dmat->bounce_flags & BF_COHERENT) == 0) 1001 cpu_dcache_wbinv_range(bpage->vaddr, 1002 bpage->datacount); 1003 bpage = STAILQ_NEXT(bpage, links); 1004 } 1005 } 1006 1007 if ((op & BUS_DMASYNC_POSTREAD) != 0) { 1008 while (bpage != NULL) { 1009 if ((dmat->bounce_flags & BF_COHERENT) == 0) 1010 cpu_dcache_inv_range(bpage->vaddr, 1011 bpage->datacount); 1012 tempvaddr = 0; 1013 datavaddr = bpage->datavaddr; 1014 if (datavaddr == 0) { 1015 tempvaddr = pmap_quick_enter_page( 1016 bpage->datapage); 1017 datavaddr = tempvaddr | bpage->dataoffs; 1018 } 1019 1020 bcopy((void *)bpage->vaddr, 1021 (void *)datavaddr, bpage->datacount); 1022 1023 if (tempvaddr != 0) 1024 pmap_quick_remove_page(tempvaddr); 1025 bpage = STAILQ_NEXT(bpage, links); 1026 } 1027 dmat->bounce_zone->total_bounced++; 1028 } 1029 } 1030 1031 /* 1032 * Cache maintenance for normal (non-COHERENT non-bounce) buffers. 1033 */ 1034 if (map->sync_count != 0) { 1035 sl = &map->slist[0]; 1036 end = &map->slist[map->sync_count]; 1037 CTR3(KTR_BUSDMA, "%s: tag %p op 0x%x " 1038 "performing sync", __func__, dmat, op); 1039 1040 for ( ; sl != end; ++sl) 1041 dma_dcache_sync(sl, op); 1042 } 1043 1044 if ((op & (BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE)) != 0) { 1045 /* 1046 * Wait for the bcopy to complete before any DMA operations. 1047 */ 1048 dsb(sy); 1049 } 1050 } 1051 1052 static void 1053 init_bounce_pages(void *dummy __unused) 1054 { 1055 1056 total_bpages = 0; 1057 STAILQ_INIT(&bounce_zone_list); 1058 STAILQ_INIT(&bounce_map_waitinglist); 1059 STAILQ_INIT(&bounce_map_callbacklist); 1060 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 1061 } 1062 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 1063 1064 static struct sysctl_ctx_list * 1065 busdma_sysctl_tree(struct bounce_zone *bz) 1066 { 1067 1068 return (&bz->sysctl_tree); 1069 } 1070 1071 static struct sysctl_oid * 1072 busdma_sysctl_tree_top(struct bounce_zone *bz) 1073 { 1074 1075 return (bz->sysctl_tree_top); 1076 } 1077 1078 static int 1079 alloc_bounce_zone(bus_dma_tag_t dmat) 1080 { 1081 struct bounce_zone *bz; 1082 1083 /* Check to see if we already have a suitable zone */ 1084 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 1085 if ((dmat->common.alignment <= bz->alignment) && 1086 (dmat->common.lowaddr >= bz->lowaddr)) { 1087 dmat->bounce_zone = bz; 1088 return (0); 1089 } 1090 } 1091 1092 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 1093 M_NOWAIT | M_ZERO)) == NULL) 1094 return (ENOMEM); 1095 1096 STAILQ_INIT(&bz->bounce_page_list); 1097 bz->free_bpages = 0; 1098 bz->reserved_bpages = 0; 1099 bz->active_bpages = 0; 1100 bz->lowaddr = dmat->common.lowaddr; 1101 bz->alignment = MAX(dmat->common.alignment, PAGE_SIZE); 1102 bz->map_count = 0; 1103 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 1104 busdma_zonecount++; 1105 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 1106 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 1107 dmat->bounce_zone = bz; 1108 1109 sysctl_ctx_init(&bz->sysctl_tree); 1110 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 1111 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1112 CTLFLAG_RD, 0, ""); 1113 if (bz->sysctl_tree_top == NULL) { 1114 sysctl_ctx_free(&bz->sysctl_tree); 1115 return (0); /* XXX error code? */ 1116 } 1117 1118 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1119 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1120 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1121 "Total bounce pages"); 1122 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1123 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1124 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1125 "Free bounce pages"); 1126 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1127 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1128 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1129 "Reserved bounce pages"); 1130 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1131 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1132 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1133 "Active bounce pages"); 1134 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1135 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1136 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1137 "Total bounce requests"); 1138 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1139 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1140 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1141 "Total bounce requests that were deferred"); 1142 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1143 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1144 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1145 SYSCTL_ADD_UAUTO(busdma_sysctl_tree(bz), 1146 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1147 "alignment", CTLFLAG_RD, &bz->alignment, ""); 1148 1149 return (0); 1150 } 1151 1152 static int 1153 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1154 { 1155 struct bounce_zone *bz; 1156 int count; 1157 1158 bz = dmat->bounce_zone; 1159 count = 0; 1160 while (numpages > 0) { 1161 struct bounce_page *bpage; 1162 1163 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 1164 M_NOWAIT | M_ZERO); 1165 1166 if (bpage == NULL) 1167 break; 1168 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1169 M_NOWAIT, 0ul, bz->lowaddr, PAGE_SIZE, 0); 1170 if (bpage->vaddr == 0) { 1171 free(bpage, M_DEVBUF); 1172 break; 1173 } 1174 bpage->busaddr = pmap_kextract(bpage->vaddr); 1175 mtx_lock(&bounce_lock); 1176 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1177 total_bpages++; 1178 bz->total_bpages++; 1179 bz->free_bpages++; 1180 mtx_unlock(&bounce_lock); 1181 count++; 1182 numpages--; 1183 } 1184 return (count); 1185 } 1186 1187 static int 1188 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1189 { 1190 struct bounce_zone *bz; 1191 int pages; 1192 1193 mtx_assert(&bounce_lock, MA_OWNED); 1194 bz = dmat->bounce_zone; 1195 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1196 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1197 return (map->pagesneeded - (map->pagesreserved + pages)); 1198 bz->free_bpages -= pages; 1199 bz->reserved_bpages += pages; 1200 map->pagesreserved += pages; 1201 pages = map->pagesneeded - map->pagesreserved; 1202 1203 return (pages); 1204 } 1205 1206 static bus_addr_t 1207 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1208 bus_addr_t addr, bus_size_t size) 1209 { 1210 struct bounce_zone *bz; 1211 struct bounce_page *bpage; 1212 1213 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1214 KASSERT((map->flags & DMAMAP_COULD_BOUNCE) != 0, 1215 ("add_bounce_page: bad map %p", map)); 1216 1217 bz = dmat->bounce_zone; 1218 if (map->pagesneeded == 0) 1219 panic("add_bounce_page: map doesn't need any pages"); 1220 map->pagesneeded--; 1221 1222 if (map->pagesreserved == 0) 1223 panic("add_bounce_page: map doesn't need any pages"); 1224 map->pagesreserved--; 1225 1226 mtx_lock(&bounce_lock); 1227 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1228 if (bpage == NULL) 1229 panic("add_bounce_page: free page list is empty"); 1230 1231 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1232 bz->reserved_bpages--; 1233 bz->active_bpages++; 1234 mtx_unlock(&bounce_lock); 1235 1236 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) { 1237 /* Page offset needs to be preserved. */ 1238 bpage->vaddr |= addr & PAGE_MASK; 1239 bpage->busaddr |= addr & PAGE_MASK; 1240 } 1241 bpage->datavaddr = vaddr; 1242 bpage->datapage = PHYS_TO_VM_PAGE(addr); 1243 bpage->dataoffs = addr & PAGE_MASK; 1244 bpage->datacount = size; 1245 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1246 return (bpage->busaddr); 1247 } 1248 1249 static void 1250 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1251 { 1252 struct bus_dmamap *map; 1253 struct bounce_zone *bz; 1254 1255 bz = dmat->bounce_zone; 1256 bpage->datavaddr = 0; 1257 bpage->datacount = 0; 1258 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) { 1259 /* 1260 * Reset the bounce page to start at offset 0. Other uses 1261 * of this bounce page may need to store a full page of 1262 * data and/or assume it starts on a page boundary. 1263 */ 1264 bpage->vaddr &= ~PAGE_MASK; 1265 bpage->busaddr &= ~PAGE_MASK; 1266 } 1267 1268 mtx_lock(&bounce_lock); 1269 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1270 bz->free_bpages++; 1271 bz->active_bpages--; 1272 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1273 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1274 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1275 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1276 map, links); 1277 busdma_swi_pending = 1; 1278 bz->total_deferred++; 1279 swi_sched(vm_ih, 0); 1280 } 1281 } 1282 mtx_unlock(&bounce_lock); 1283 } 1284 1285 void 1286 busdma_swi(void) 1287 { 1288 bus_dma_tag_t dmat; 1289 struct bus_dmamap *map; 1290 1291 mtx_lock(&bounce_lock); 1292 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1293 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1294 mtx_unlock(&bounce_lock); 1295 dmat = map->dmat; 1296 (dmat->common.lockfunc)(dmat->common.lockfuncarg, BUS_DMA_LOCK); 1297 bus_dmamap_load_mem(map->dmat, map, &map->mem, 1298 map->callback, map->callback_arg, BUS_DMA_WAITOK); 1299 (dmat->common.lockfunc)(dmat->common.lockfuncarg, 1300 BUS_DMA_UNLOCK); 1301 mtx_lock(&bounce_lock); 1302 } 1303 mtx_unlock(&bounce_lock); 1304 } 1305 1306 struct bus_dma_impl bus_dma_bounce_impl = { 1307 .tag_create = bounce_bus_dma_tag_create, 1308 .tag_destroy = bounce_bus_dma_tag_destroy, 1309 .map_create = bounce_bus_dmamap_create, 1310 .map_destroy = bounce_bus_dmamap_destroy, 1311 .mem_alloc = bounce_bus_dmamem_alloc, 1312 .mem_free = bounce_bus_dmamem_free, 1313 .load_phys = bounce_bus_dmamap_load_phys, 1314 .load_buffer = bounce_bus_dmamap_load_buffer, 1315 .load_ma = bus_dmamap_load_ma_triv, 1316 .map_waitok = bounce_bus_dmamap_waitok, 1317 .map_complete = bounce_bus_dmamap_complete, 1318 .map_unload = bounce_bus_dmamap_unload, 1319 .map_sync = bounce_bus_dmamap_sync 1320 }; 1321