busdma_machdep.c revision 168822
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#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: head/sys/i386/i386/busdma_machdep.c 168822 2007-04-17 21:05:34Z jhb $"); 29 30#include <sys/param.h> 31#include <sys/kdb.h> 32#include <ddb/ddb.h> 33#include <ddb/db_output.h> 34#include <sys/systm.h> 35#include <sys/malloc.h> 36#include <sys/bus.h> 37#include <sys/interrupt.h> 38#include <sys/kernel.h> 39#include <sys/ktr.h> 40#include <sys/lock.h> 41#include <sys/proc.h> 42#include <sys/mutex.h> 43#include <sys/mbuf.h> 44#include <sys/uio.h> 45#include <sys/sysctl.h> 46 47#include <vm/vm.h> 48#include <vm/vm_page.h> 49#include <vm/vm_map.h> 50 51#include <machine/atomic.h> 52#include <machine/bus.h> 53#include <machine/md_var.h> 54#include <machine/specialreg.h> 55 56#define MAX_BPAGES 512 57#define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3 58#define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 59 60struct bounce_zone; 61 62struct bus_dma_tag { 63 bus_dma_tag_t parent; 64 bus_size_t alignment; 65 bus_size_t boundary; 66 bus_addr_t lowaddr; 67 bus_addr_t highaddr; 68 bus_dma_filter_t *filter; 69 void *filterarg; 70 bus_size_t maxsize; 71 u_int nsegments; 72 bus_size_t maxsegsz; 73 int flags; 74 int ref_count; 75 int map_count; 76 bus_dma_lock_t *lockfunc; 77 void *lockfuncarg; 78 bus_dma_segment_t *segments; 79 struct bounce_zone *bounce_zone; 80}; 81 82struct bounce_page { 83 vm_offset_t vaddr; /* kva of bounce buffer */ 84 bus_addr_t busaddr; /* Physical address */ 85 vm_offset_t datavaddr; /* kva of client data */ 86 bus_size_t datacount; /* client data count */ 87 STAILQ_ENTRY(bounce_page) links; 88}; 89 90int busdma_swi_pending; 91 92struct bounce_zone { 93 STAILQ_ENTRY(bounce_zone) links; 94 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 95 int total_bpages; 96 int free_bpages; 97 int reserved_bpages; 98 int active_bpages; 99 int total_bounced; 100 int total_deferred; 101 bus_size_t alignment; 102 bus_size_t boundary; 103 bus_addr_t lowaddr; 104 char zoneid[8]; 105 char lowaddrid[20]; 106 struct sysctl_ctx_list sysctl_tree; 107 struct sysctl_oid *sysctl_tree_top; 108}; 109 110static struct mtx bounce_lock; 111static int total_bpages; 112static int busdma_zonecount; 113static STAILQ_HEAD(, bounce_zone) bounce_zone_list; 114 115SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 116SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 117 "Total bounce pages"); 118 119struct bus_dmamap { 120 struct bp_list bpages; 121 int pagesneeded; 122 int pagesreserved; 123 bus_dma_tag_t dmat; 124 void *buf; /* unmapped buffer pointer */ 125 bus_size_t buflen; /* unmapped buffer length */ 126 bus_dmamap_callback_t *callback; 127 void *callback_arg; 128 STAILQ_ENTRY(bus_dmamap) links; 129}; 130 131static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 132static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 133static struct bus_dmamap nobounce_dmamap; 134 135static void init_bounce_pages(void *dummy); 136static int alloc_bounce_zone(bus_dma_tag_t dmat); 137static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 138static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 139 int commit); 140static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 141 vm_offset_t vaddr, bus_size_t size); 142static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 143int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr); 144int _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 145 bus_size_t buflen, int flags, int *nb); 146 147/* 148 * Return true if a match is made. 149 * 150 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'. 151 * 152 * If paddr is within the bounds of the dma tag then call the filter callback 153 * to check for a match, if there is no filter callback then assume a match. 154 */ 155int 156run_filter(bus_dma_tag_t dmat, bus_addr_t paddr) 157{ 158 int retval; 159 160 retval = 0; 161 162 do { 163 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) 164 || ((paddr & (dmat->alignment - 1)) != 0)) 165 && (dmat->filter == NULL 166 || (*dmat->filter)(dmat->filterarg, paddr) != 0)) 167 retval = 1; 168 169 dmat = dmat->parent; 170 } while (retval == 0 && dmat != NULL); 171 return (retval); 172} 173 174/* 175 * Convenience function for manipulating driver locks from busdma (during 176 * busdma_swi, for example). Drivers that don't provide their own locks 177 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own 178 * non-mutex locking scheme don't have to use this at all. 179 */ 180void 181busdma_lock_mutex(void *arg, bus_dma_lock_op_t op) 182{ 183 struct mtx *dmtx; 184 185 dmtx = (struct mtx *)arg; 186 switch (op) { 187 case BUS_DMA_LOCK: 188 mtx_lock(dmtx); 189 break; 190 case BUS_DMA_UNLOCK: 191 mtx_unlock(dmtx); 192 break; 193 default: 194 panic("Unknown operation 0x%x for busdma_lock_mutex!", op); 195 } 196} 197 198/* 199 * dflt_lock should never get called. It gets put into the dma tag when 200 * lockfunc == NULL, which is only valid if the maps that are associated 201 * with the tag are meant to never be defered. 202 * XXX Should have a way to identify which driver is responsible here. 203 */ 204static void 205dflt_lock(void *arg, bus_dma_lock_op_t op) 206{ 207 panic("driver error: busdma dflt_lock called"); 208} 209 210/* 211 * Allocate a device specific dma_tag. 212 */ 213int 214bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 215 bus_size_t boundary, bus_addr_t lowaddr, 216 bus_addr_t highaddr, bus_dma_filter_t *filter, 217 void *filterarg, bus_size_t maxsize, int nsegments, 218 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 219 void *lockfuncarg, bus_dma_tag_t *dmat) 220{ 221 bus_dma_tag_t newtag; 222 int error = 0; 223 224 /* Basic sanity checking */ 225 if (boundary != 0 && boundary < maxsegsz) 226 maxsegsz = boundary; 227 228 /* Return a NULL tag on failure */ 229 *dmat = NULL; 230 231 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, 232 M_ZERO | M_NOWAIT); 233 if (newtag == NULL) { 234 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 235 __func__, newtag, 0, error); 236 return (ENOMEM); 237 } 238 239 newtag->parent = parent; 240 newtag->alignment = alignment; 241 newtag->boundary = boundary; 242 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 243 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + 244 (PAGE_SIZE - 1); 245 newtag->filter = filter; 246 newtag->filterarg = filterarg; 247 newtag->maxsize = maxsize; 248 newtag->nsegments = nsegments; 249 newtag->maxsegsz = maxsegsz; 250 newtag->flags = flags; 251 newtag->ref_count = 1; /* Count ourself */ 252 newtag->map_count = 0; 253 if (lockfunc != NULL) { 254 newtag->lockfunc = lockfunc; 255 newtag->lockfuncarg = lockfuncarg; 256 } else { 257 newtag->lockfunc = dflt_lock; 258 newtag->lockfuncarg = NULL; 259 } 260 newtag->segments = NULL; 261 262 /* Take into account any restrictions imposed by our parent tag */ 263 if (parent != NULL) { 264 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 265 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 266 if (newtag->boundary == 0) 267 newtag->boundary = parent->boundary; 268 else if (parent->boundary != 0) 269 newtag->boundary = MIN(parent->boundary, 270 newtag->boundary); 271 if ((newtag->filter != NULL) || 272 ((parent->flags & BUS_DMA_COULD_BOUNCE) != 0)) 273 newtag->flags |= BUS_DMA_COULD_BOUNCE; 274 if (newtag->filter == NULL) { 275 /* 276 * Short circuit looking at our parent directly 277 * since we have encapsulated all of its information 278 */ 279 newtag->filter = parent->filter; 280 newtag->filterarg = parent->filterarg; 281 newtag->parent = parent->parent; 282 } 283 if (newtag->parent != NULL) 284 atomic_add_int(&parent->ref_count, 1); 285 } 286 287 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) 288 || newtag->alignment > 1) 289 newtag->flags |= BUS_DMA_COULD_BOUNCE; 290 291 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) && 292 (flags & BUS_DMA_ALLOCNOW) != 0) { 293 struct bounce_zone *bz; 294 295 /* Must bounce */ 296 297 if ((error = alloc_bounce_zone(newtag)) != 0) { 298 free(newtag, M_DEVBUF); 299 return (error); 300 } 301 bz = newtag->bounce_zone; 302 303 if (ptoa(bz->total_bpages) < maxsize) { 304 int pages; 305 306 pages = atop(maxsize) - bz->total_bpages; 307 308 /* Add pages to our bounce pool */ 309 if (alloc_bounce_pages(newtag, pages) < pages) 310 error = ENOMEM; 311 } 312 /* Performed initial allocation */ 313 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 314 } 315 316 if (error != 0) { 317 free(newtag, M_DEVBUF); 318 } else { 319 *dmat = newtag; 320 } 321 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 322 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error); 323 return (error); 324} 325 326int 327bus_dma_tag_destroy(bus_dma_tag_t dmat) 328{ 329 bus_dma_tag_t dmat_copy; 330 int error; 331 332 error = 0; 333 dmat_copy = dmat; 334 335 if (dmat != NULL) { 336 337 if (dmat->map_count != 0) { 338 error = EBUSY; 339 goto out; 340 } 341 342 while (dmat != NULL) { 343 bus_dma_tag_t parent; 344 345 parent = dmat->parent; 346 atomic_subtract_int(&dmat->ref_count, 1); 347 if (dmat->ref_count == 0) { 348 if (dmat->segments != NULL) 349 free(dmat->segments, M_DEVBUF); 350 free(dmat, M_DEVBUF); 351 /* 352 * Last reference count, so 353 * release our reference 354 * count on our parent. 355 */ 356 dmat = parent; 357 } else 358 dmat = NULL; 359 } 360 } 361out: 362 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 363 return (error); 364} 365 366/* 367 * Allocate a handle for mapping from kva/uva/physical 368 * address space into bus device space. 369 */ 370int 371bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 372{ 373 int error; 374 375 error = 0; 376 377 if (dmat->segments == NULL) { 378 dmat->segments = (bus_dma_segment_t *)malloc( 379 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 380 M_NOWAIT); 381 if (dmat->segments == NULL) { 382 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 383 __func__, dmat, ENOMEM); 384 return (ENOMEM); 385 } 386 } 387 388 /* 389 * Bouncing might be required if the driver asks for an active 390 * exclusion region, a data alignment that is stricter than 1, and/or 391 * an active address boundary. 392 */ 393 if (dmat->flags & BUS_DMA_COULD_BOUNCE) { 394 395 /* Must bounce */ 396 struct bounce_zone *bz; 397 int maxpages; 398 399 if (dmat->bounce_zone == NULL) { 400 if ((error = alloc_bounce_zone(dmat)) != 0) 401 return (error); 402 } 403 bz = dmat->bounce_zone; 404 405 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF, 406 M_NOWAIT | M_ZERO); 407 if (*mapp == NULL) { 408 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 409 __func__, dmat, ENOMEM); 410 return (ENOMEM); 411 } 412 413 /* Initialize the new map */ 414 STAILQ_INIT(&((*mapp)->bpages)); 415 416 /* 417 * Attempt to add pages to our pool on a per-instance 418 * basis up to a sane limit. 419 */ 420 if (dmat->alignment > 1) 421 maxpages = MAX_BPAGES; 422 else 423 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr)); 424 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 425 || (dmat->map_count > 0 && bz->total_bpages < maxpages)) { 426 int pages; 427 428 pages = MAX(atop(dmat->maxsize), 1); 429 pages = MIN(maxpages - bz->total_bpages, pages); 430 pages = MAX(pages, 1); 431 if (alloc_bounce_pages(dmat, pages) < pages) 432 error = ENOMEM; 433 434 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 435 if (error == 0) 436 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 437 } else { 438 error = 0; 439 } 440 } 441 } else { 442 *mapp = NULL; 443 } 444 if (error == 0) 445 dmat->map_count++; 446 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 447 __func__, dmat, dmat->flags, error); 448 return (error); 449} 450 451/* 452 * Destroy a handle for mapping from kva/uva/physical 453 * address space into bus device space. 454 */ 455int 456bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 457{ 458 if (map != NULL && map != &nobounce_dmamap) { 459 if (STAILQ_FIRST(&map->bpages) != NULL) { 460 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 461 __func__, dmat, EBUSY); 462 return (EBUSY); 463 } 464 free(map, M_DEVBUF); 465 } 466 dmat->map_count--; 467 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 468 return (0); 469} 470 471 472/* 473 * Allocate a piece of memory that can be efficiently mapped into 474 * bus device space based on the constraints lited in the dma tag. 475 * A dmamap to for use with dmamap_load is also allocated. 476 */ 477int 478bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 479 bus_dmamap_t *mapp) 480{ 481 int mflags; 482 483 if (flags & BUS_DMA_NOWAIT) 484 mflags = M_NOWAIT; 485 else 486 mflags = M_WAITOK; 487 if (flags & BUS_DMA_ZERO) 488 mflags |= M_ZERO; 489 490 /* If we succeed, no mapping/bouncing will be required */ 491 *mapp = NULL; 492 493 if (dmat->segments == NULL) { 494 dmat->segments = (bus_dma_segment_t *)malloc( 495 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 496 M_NOWAIT); 497 if (dmat->segments == NULL) { 498 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 499 __func__, dmat, dmat->flags, ENOMEM); 500 return (ENOMEM); 501 } 502 } 503 504 /* 505 * XXX: 506 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact 507 * alignment guarantees of malloc need to be nailed down, and the 508 * code below should be rewritten to take that into account. 509 * 510 * In the meantime, we'll warn the user if malloc gets it wrong. 511 */ 512 if ((dmat->maxsize <= PAGE_SIZE) && 513 (dmat->alignment < dmat->maxsize) && 514 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) { 515 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags); 516 } else { 517 /* 518 * XXX Use Contigmalloc until it is merged into this facility 519 * and handles multi-seg allocations. Nobody is doing 520 * multi-seg allocations yet though. 521 * XXX Certain AGP hardware does. 522 */ 523 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 524 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul, 525 dmat->boundary); 526 } 527 if (*vaddr == NULL) { 528 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 529 __func__, dmat, dmat->flags, ENOMEM); 530 return (ENOMEM); 531 } else if ((uintptr_t)*vaddr & (dmat->alignment - 1)) { 532 printf("bus_dmamem_alloc failed to align memory properly.\n"); 533 } 534 if (flags & BUS_DMA_NOCACHE) 535 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize, 536 PAT_UNCACHEABLE); 537 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 538 __func__, dmat, dmat->flags, ENOMEM); 539 return (0); 540} 541 542/* 543 * Free a piece of memory and it's allociated dmamap, that was allocated 544 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 545 */ 546void 547bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 548{ 549 /* 550 * dmamem does not need to be bounced, so the map should be 551 * NULL 552 */ 553 if (map != NULL) 554 panic("bus_dmamem_free: Invalid map freed\n"); 555 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK); 556 if ((dmat->maxsize <= PAGE_SIZE) && 557 (dmat->alignment < dmat->maxsize) && 558 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) 559 free(vaddr, M_DEVBUF); 560 else { 561 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 562 } 563 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags); 564} 565 566int 567_bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 568 bus_size_t buflen, int flags, int *nb) 569{ 570 vm_offset_t vaddr; 571 vm_offset_t vendaddr; 572 bus_addr_t paddr; 573 int needbounce = *nb; 574 575 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) { 576 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 577 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem), 578 dmat->boundary, dmat->alignment); 579 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 580 map, &nobounce_dmamap, map->pagesneeded); 581 /* 582 * Count the number of bounce pages 583 * needed in order to complete this transfer 584 */ 585 vaddr = trunc_page((vm_offset_t)buf); 586 vendaddr = (vm_offset_t)buf + buflen; 587 588 while (vaddr < vendaddr) { 589 paddr = pmap_kextract(vaddr); 590 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) && 591 run_filter(dmat, paddr) != 0) { 592 needbounce = 1; 593 map->pagesneeded++; 594 } 595 vaddr += PAGE_SIZE; 596 } 597 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 598 } 599 600 /* Reserve Necessary Bounce Pages */ 601 if (map->pagesneeded != 0) { 602 mtx_lock(&bounce_lock); 603 if (flags & BUS_DMA_NOWAIT) { 604 if (reserve_bounce_pages(dmat, map, 0) != 0) { 605 mtx_unlock(&bounce_lock); 606 return (ENOMEM); 607 } 608 } else { 609 if (reserve_bounce_pages(dmat, map, 1) != 0) { 610 /* Queue us for resources */ 611 map->dmat = dmat; 612 map->buf = buf; 613 map->buflen = buflen; 614 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, 615 map, links); 616 mtx_unlock(&bounce_lock); 617 return (EINPROGRESS); 618 } 619 } 620 mtx_unlock(&bounce_lock); 621 } 622 623 *nb = needbounce; 624 return (0); 625} 626 627/* 628 * Utility function to load a linear buffer. lastaddrp holds state 629 * between invocations (for multiple-buffer loads). segp contains 630 * the starting segment on entrace, and the ending segment on exit. 631 * first indicates if this is the first invocation of this function. 632 */ 633static __inline int 634_bus_dmamap_load_buffer(bus_dma_tag_t dmat, 635 bus_dmamap_t map, 636 void *buf, bus_size_t buflen, 637 pmap_t pmap, 638 int flags, 639 bus_addr_t *lastaddrp, 640 bus_dma_segment_t *segs, 641 int *segp, 642 int first) 643{ 644 bus_size_t sgsize; 645 bus_addr_t curaddr, lastaddr, baddr, bmask; 646 vm_offset_t vaddr; 647 int needbounce = 0; 648 int seg, error; 649 650 if (map == NULL) 651 map = &nobounce_dmamap; 652 653 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) { 654 error = _bus_dmamap_count_pages(dmat, map, buf, buflen, flags, 655 &needbounce); 656 if (error) 657 return (error); 658 } 659 660 vaddr = (vm_offset_t)buf; 661 lastaddr = *lastaddrp; 662 bmask = ~(dmat->boundary - 1); 663 664 for (seg = *segp; buflen > 0 ; ) { 665 /* 666 * Get the physical address for this segment. 667 */ 668 if (pmap) 669 curaddr = pmap_extract(pmap, vaddr); 670 else 671 curaddr = pmap_kextract(vaddr); 672 673 /* 674 * Compute the segment size, and adjust counts. 675 */ 676 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK); 677 if (buflen < sgsize) 678 sgsize = buflen; 679 680 /* 681 * Make sure we don't cross any boundaries. 682 */ 683 if (dmat->boundary > 0) { 684 baddr = (curaddr + dmat->boundary) & bmask; 685 if (sgsize > (baddr - curaddr)) 686 sgsize = (baddr - curaddr); 687 } 688 689 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) && 690 map->pagesneeded != 0 && run_filter(dmat, curaddr)) 691 curaddr = add_bounce_page(dmat, map, vaddr, sgsize); 692 693 /* 694 * Insert chunk into a segment, coalescing with 695 * previous segment if possible. 696 */ 697 if (first) { 698 segs[seg].ds_addr = curaddr; 699 segs[seg].ds_len = sgsize; 700 first = 0; 701 } else { 702 if (needbounce == 0 && curaddr == lastaddr && 703 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz && 704 (dmat->boundary == 0 || 705 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 706 segs[seg].ds_len += sgsize; 707 else { 708 if (++seg >= dmat->nsegments) 709 break; 710 segs[seg].ds_addr = curaddr; 711 segs[seg].ds_len = sgsize; 712 } 713 } 714 715 lastaddr = curaddr + sgsize; 716 vaddr += sgsize; 717 buflen -= sgsize; 718 } 719 720 *segp = seg; 721 *lastaddrp = lastaddr; 722 723 /* 724 * Did we fit? 725 */ 726 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 727} 728 729/* 730 * Map the buffer buf into bus space using the dmamap map. 731 */ 732int 733bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 734 bus_size_t buflen, bus_dmamap_callback_t *callback, 735 void *callback_arg, int flags) 736{ 737 bus_addr_t lastaddr = 0; 738 int error, nsegs = 0; 739 740 if (map != NULL) { 741 flags |= BUS_DMA_WAITOK; 742 map->callback = callback; 743 map->callback_arg = callback_arg; 744 } 745 746 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags, 747 &lastaddr, dmat->segments, &nsegs, 1); 748 749 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 750 __func__, dmat, dmat->flags, error, nsegs + 1); 751 752 if (error == EINPROGRESS) { 753 return (error); 754 } 755 756 if (error) 757 (*callback)(callback_arg, dmat->segments, 0, error); 758 else 759 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0); 760 761 /* 762 * Return ENOMEM to the caller so that it can pass it up the stack. 763 * This error only happens when NOWAIT is set, so deferal is disabled. 764 */ 765 if (error == ENOMEM) 766 return (error); 767 768 return (0); 769} 770 771 772/* 773 * Like _bus_dmamap_load(), but for mbufs. 774 */ 775static __inline int 776_bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, 777 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, 778 int flags) 779{ 780 int error; 781 782 M_ASSERTPKTHDR(m0); 783 784 flags |= BUS_DMA_NOWAIT; 785 *nsegs = 0; 786 error = 0; 787 if (m0->m_pkthdr.len <= dmat->maxsize) { 788 int first = 1; 789 bus_addr_t lastaddr = 0; 790 struct mbuf *m; 791 792 for (m = m0; m != NULL && error == 0; m = m->m_next) { 793 if (m->m_len > 0) { 794 error = _bus_dmamap_load_buffer(dmat, map, 795 m->m_data, m->m_len, 796 NULL, flags, &lastaddr, 797 segs, nsegs, first); 798 first = 0; 799 } 800 } 801 } else { 802 error = EINVAL; 803 } 804 805 /* XXX FIXME: Having to increment nsegs is really annoying */ 806 ++*nsegs; 807 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 808 __func__, dmat, dmat->flags, error, *nsegs); 809 return (error); 810} 811 812int 813bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 814 struct mbuf *m0, 815 bus_dmamap_callback2_t *callback, void *callback_arg, 816 int flags) 817{ 818 int nsegs, error; 819 820 error = _bus_dmamap_load_mbuf_sg(dmat, map, m0, dmat->segments, &nsegs, 821 flags); 822 823 if (error) { 824 /* force "no valid mappings" in callback */ 825 (*callback)(callback_arg, dmat->segments, 0, 0, error); 826 } else { 827 (*callback)(callback_arg, dmat->segments, 828 nsegs, m0->m_pkthdr.len, error); 829 } 830 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 831 __func__, dmat, dmat->flags, error, nsegs); 832 return (error); 833} 834 835int 836bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, 837 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, 838 int flags) 839{ 840 return (_bus_dmamap_load_mbuf_sg(dmat, map, m0, segs, nsegs, flags)); 841} 842 843/* 844 * Like _bus_dmamap_load(), but for uios. 845 */ 846int 847bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 848 struct uio *uio, 849 bus_dmamap_callback2_t *callback, void *callback_arg, 850 int flags) 851{ 852 bus_addr_t lastaddr; 853 int nsegs, error, first, i; 854 bus_size_t resid; 855 struct iovec *iov; 856 pmap_t pmap; 857 858 flags |= BUS_DMA_NOWAIT; 859 resid = uio->uio_resid; 860 iov = uio->uio_iov; 861 862 if (uio->uio_segflg == UIO_USERSPACE) { 863 KASSERT(uio->uio_td != NULL, 864 ("bus_dmamap_load_uio: USERSPACE but no proc")); 865 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace); 866 } else 867 pmap = NULL; 868 869 nsegs = 0; 870 error = 0; 871 first = 1; 872 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 873 /* 874 * Now at the first iovec to load. Load each iovec 875 * until we have exhausted the residual count. 876 */ 877 bus_size_t minlen = 878 resid < iov[i].iov_len ? resid : iov[i].iov_len; 879 caddr_t addr = (caddr_t) iov[i].iov_base; 880 881 if (minlen > 0) { 882 error = _bus_dmamap_load_buffer(dmat, map, 883 addr, minlen, pmap, flags, &lastaddr, 884 dmat->segments, &nsegs, first); 885 first = 0; 886 887 resid -= minlen; 888 } 889 } 890 891 if (error) { 892 /* force "no valid mappings" in callback */ 893 (*callback)(callback_arg, dmat->segments, 0, 0, error); 894 } else { 895 (*callback)(callback_arg, dmat->segments, 896 nsegs+1, uio->uio_resid, error); 897 } 898 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 899 __func__, dmat, dmat->flags, error, nsegs + 1); 900 return (error); 901} 902 903/* 904 * Release the mapping held by map. 905 */ 906void 907_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 908{ 909 struct bounce_page *bpage; 910 911 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 912 STAILQ_REMOVE_HEAD(&map->bpages, links); 913 free_bounce_page(dmat, bpage); 914 } 915} 916 917void 918_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 919{ 920 struct bounce_page *bpage; 921 922 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 923 /* 924 * Handle data bouncing. We might also 925 * want to add support for invalidating 926 * the caches on broken hardware 927 */ 928 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 929 "performing bounce", __func__, op, dmat, dmat->flags); 930 931 if (op & BUS_DMASYNC_PREWRITE) { 932 while (bpage != NULL) { 933 bcopy((void *)bpage->datavaddr, 934 (void *)bpage->vaddr, 935 bpage->datacount); 936 bpage = STAILQ_NEXT(bpage, links); 937 } 938 dmat->bounce_zone->total_bounced++; 939 } 940 941 if (op & BUS_DMASYNC_POSTREAD) { 942 while (bpage != NULL) { 943 bcopy((void *)bpage->vaddr, 944 (void *)bpage->datavaddr, 945 bpage->datacount); 946 bpage = STAILQ_NEXT(bpage, links); 947 } 948 dmat->bounce_zone->total_bounced++; 949 } 950 } 951} 952 953static void 954init_bounce_pages(void *dummy __unused) 955{ 956 957 total_bpages = 0; 958 STAILQ_INIT(&bounce_zone_list); 959 STAILQ_INIT(&bounce_map_waitinglist); 960 STAILQ_INIT(&bounce_map_callbacklist); 961 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 962} 963SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 964 965static struct sysctl_ctx_list * 966busdma_sysctl_tree(struct bounce_zone *bz) 967{ 968 return (&bz->sysctl_tree); 969} 970 971static struct sysctl_oid * 972busdma_sysctl_tree_top(struct bounce_zone *bz) 973{ 974 return (bz->sysctl_tree_top); 975} 976 977static int 978alloc_bounce_zone(bus_dma_tag_t dmat) 979{ 980 struct bounce_zone *bz; 981 982 /* Check to see if we already have a suitable zone */ 983 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 984 if ((dmat->alignment <= bz->alignment) 985 && (dmat->boundary <= bz->boundary) 986 && (dmat->lowaddr >= bz->lowaddr)) { 987 dmat->bounce_zone = bz; 988 return (0); 989 } 990 } 991 992 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 993 M_NOWAIT | M_ZERO)) == NULL) 994 return (ENOMEM); 995 996 STAILQ_INIT(&bz->bounce_page_list); 997 bz->free_bpages = 0; 998 bz->reserved_bpages = 0; 999 bz->active_bpages = 0; 1000 bz->lowaddr = dmat->lowaddr; 1001 bz->alignment = dmat->alignment; 1002 bz->boundary = dmat->boundary; 1003 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 1004 busdma_zonecount++; 1005 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 1006 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 1007 dmat->bounce_zone = bz; 1008 1009 sysctl_ctx_init(&bz->sysctl_tree); 1010 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 1011 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1012 CTLFLAG_RD, 0, ""); 1013 if (bz->sysctl_tree_top == NULL) { 1014 sysctl_ctx_free(&bz->sysctl_tree); 1015 return (0); /* XXX error code? */ 1016 } 1017 1018 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1019 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1020 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1021 "Total bounce pages"); 1022 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1023 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1024 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1025 "Free bounce pages"); 1026 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1027 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1028 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1029 "Reserved bounce pages"); 1030 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1031 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1032 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1033 "Active bounce pages"); 1034 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1035 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1036 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1037 "Total bounce requests"); 1038 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1039 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1040 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1041 "Total bounce requests that were deferred"); 1042 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1043 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1044 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1045 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1046 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1047 "alignment", CTLFLAG_RD, &bz->alignment, 0, ""); 1048 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1049 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1050 "boundary", CTLFLAG_RD, &bz->boundary, 0, ""); 1051 1052 return (0); 1053} 1054 1055static int 1056alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1057{ 1058 struct bounce_zone *bz; 1059 int count; 1060 1061 bz = dmat->bounce_zone; 1062 count = 0; 1063 while (numpages > 0) { 1064 struct bounce_page *bpage; 1065 1066 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 1067 M_NOWAIT | M_ZERO); 1068 1069 if (bpage == NULL) 1070 break; 1071 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1072 M_NOWAIT, 0ul, 1073 bz->lowaddr, 1074 PAGE_SIZE, 1075 bz->boundary); 1076 if (bpage->vaddr == 0) { 1077 free(bpage, M_DEVBUF); 1078 break; 1079 } 1080 bpage->busaddr = pmap_kextract(bpage->vaddr); 1081 mtx_lock(&bounce_lock); 1082 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1083 total_bpages++; 1084 bz->total_bpages++; 1085 bz->free_bpages++; 1086 mtx_unlock(&bounce_lock); 1087 count++; 1088 numpages--; 1089 } 1090 return (count); 1091} 1092 1093static int 1094reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1095{ 1096 struct bounce_zone *bz; 1097 int pages; 1098 1099 mtx_assert(&bounce_lock, MA_OWNED); 1100 bz = dmat->bounce_zone; 1101 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1102 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1103 return (map->pagesneeded - (map->pagesreserved + pages)); 1104 bz->free_bpages -= pages; 1105 bz->reserved_bpages += pages; 1106 map->pagesreserved += pages; 1107 pages = map->pagesneeded - map->pagesreserved; 1108 1109 return (pages); 1110} 1111 1112static bus_addr_t 1113add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1114 bus_size_t size) 1115{ 1116 struct bounce_zone *bz; 1117 struct bounce_page *bpage; 1118 1119 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1120 KASSERT(map != NULL && map != &nobounce_dmamap, 1121 ("add_bounce_page: bad map %p", map)); 1122 1123 bz = dmat->bounce_zone; 1124 if (map->pagesneeded == 0) 1125 panic("add_bounce_page: map doesn't need any pages"); 1126 map->pagesneeded--; 1127 1128 if (map->pagesreserved == 0) 1129 panic("add_bounce_page: map doesn't need any pages"); 1130 map->pagesreserved--; 1131 1132 mtx_lock(&bounce_lock); 1133 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1134 if (bpage == NULL) 1135 panic("add_bounce_page: free page list is empty"); 1136 1137 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1138 bz->reserved_bpages--; 1139 bz->active_bpages++; 1140 mtx_unlock(&bounce_lock); 1141 1142 bpage->datavaddr = vaddr; 1143 bpage->datacount = size; 1144 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1145 return (bpage->busaddr); 1146} 1147 1148static void 1149free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1150{ 1151 struct bus_dmamap *map; 1152 struct bounce_zone *bz; 1153 1154 bz = dmat->bounce_zone; 1155 bpage->datavaddr = 0; 1156 bpage->datacount = 0; 1157 1158 mtx_lock(&bounce_lock); 1159 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1160 bz->free_bpages++; 1161 bz->active_bpages--; 1162 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1163 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1164 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1165 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1166 map, links); 1167 busdma_swi_pending = 1; 1168 bz->total_deferred++; 1169 swi_sched(vm_ih, 0); 1170 } 1171 } 1172 mtx_unlock(&bounce_lock); 1173} 1174 1175void 1176busdma_swi(void) 1177{ 1178 bus_dma_tag_t dmat; 1179 struct bus_dmamap *map; 1180 1181 mtx_lock(&bounce_lock); 1182 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1183 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1184 mtx_unlock(&bounce_lock); 1185 dmat = map->dmat; 1186 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK); 1187 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1188 map->callback, map->callback_arg, /*flags*/0); 1189 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK); 1190 mtx_lock(&bounce_lock); 1191 } 1192 mtx_unlock(&bounce_lock); 1193} 1194