busdma_machdep.c revision 132544
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 132544 2004-07-22 15:46:51Z scottl $"); 29 30#include <sys/param.h> 31#include <sys/systm.h> 32#include <sys/malloc.h> 33#include <sys/bus.h> 34#include <sys/interrupt.h> 35#include <sys/kernel.h> 36#include <sys/lock.h> 37#include <sys/proc.h> 38#include <sys/mutex.h> 39#include <sys/mbuf.h> 40#include <sys/uio.h> 41#include <sys/sysctl.h> 42 43#include <vm/vm.h> 44#include <vm/vm_page.h> 45#include <vm/vm_map.h> 46 47#include <machine/atomic.h> 48#include <machine/bus.h> 49#include <machine/md_var.h> 50 51#define MAX_BPAGES 512 52 53struct bounce_page { 54 vm_offset_t vaddr; /* kva of bounce buffer */ 55 bus_addr_t busaddr; /* Physical address */ 56 vm_offset_t datavaddr; /* kva of client data */ 57 bus_size_t datacount; /* client data count */ 58 STAILQ_ENTRY(bounce_page) links; 59}; 60 61struct bus_dma_tag { 62 bus_dma_tag_t parent; 63 bus_size_t alignment; 64 bus_size_t boundary; 65 bus_addr_t lowaddr; 66 bus_addr_t highaddr; 67 bus_dma_filter_t *filter; 68 void *filterarg; 69 bus_size_t maxsize; 70 u_int nsegments; 71 bus_size_t maxsegsz; 72 int flags; 73 int ref_count; 74 int map_count; 75 bus_dma_lock_t *lockfunc; 76 void *lockfuncarg; 77 bus_dma_segment_t *segments; 78 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 79}; 80 81int busdma_swi_pending; 82 83/* 84 * In order to reduce extra lock/unlock sequences in the main bounce path, 85 * this lock covers the global bounce lists and the dmat bounce lists. 86 */ 87static struct mtx bounce_lock; 88static int free_bpages; 89static int reserved_bpages; 90static int active_bpages; 91static int total_bpages; 92static int total_bounced; 93static int total_deferred; 94static bus_addr_t bounce_lowaddr = BUS_SPACE_MAXADDR; 95 96SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 97SYSCTL_INT(_hw_busdma, OID_AUTO, free_bpages, CTLFLAG_RD, &free_bpages, 0, 98 "Free bounce pages"); 99SYSCTL_INT(_hw_busdma, OID_AUTO, reserved_bpages, CTLFLAG_RD, &reserved_bpages, 100 0, "Reserved bounce pages"); 101SYSCTL_INT(_hw_busdma, OID_AUTO, active_bpages, CTLFLAG_RD, &active_bpages, 0, 102 "Active bounce pages"); 103SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 104 "Total bounce pages"); 105SYSCTL_INT(_hw_busdma, OID_AUTO, total_bounced, CTLFLAG_RD, &total_bounced, 0, 106 "Total bounce requests"); 107SYSCTL_INT(_hw_busdma, OID_AUTO, total_deferred, CTLFLAG_RD, &total_deferred, 0, 108 "Total bounce requests that were deferred"); 109 110struct bus_dmamap { 111 struct bp_list bpages; 112 int pagesneeded; 113 int pagesreserved; 114 bus_dma_tag_t dmat; 115 void *buf; /* unmapped buffer pointer */ 116 bus_size_t buflen; /* unmapped buffer length */ 117 bus_dmamap_callback_t *callback; 118 void *callback_arg; 119 STAILQ_ENTRY(bus_dmamap) links; 120}; 121 122static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 123static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 124static struct bus_dmamap nobounce_dmamap; 125 126static void init_bounce_pages(void *dummy); 127static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 128static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 129 int commit); 130static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 131 vm_offset_t vaddr, bus_size_t size); 132static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 133static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr, 134 bus_size_t len, struct bus_dmamap *map); 135 136/* 137 * Return true if a match is made. 138 * 139 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'. 140 * 141 * If paddr is within the bounds of the dma tag then call the filter callback 142 * to check for a match, if there is no filter callback then assume a match. 143 */ 144static __inline int 145run_filter(bus_dma_tag_t dmat, bus_addr_t paddr, bus_size_t len, struct bus_dmamap *map) 146{ 147 bus_addr_t endaddr; 148 bus_size_t bndy; 149 int retval; 150 151 retval = 0; 152 bndy = dmat->boundary; 153 endaddr = paddr + len - 1; 154 155 do { 156 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) 157 || ((paddr & (dmat->alignment - 1)) != 0) 158 || ((paddr & bndy) != (endaddr & bndy))) 159 && (dmat->filter == NULL 160 || (*dmat->filter)(dmat->filterarg, paddr) != 0)) { 161 if ((paddr & (dmat->alignment - 1)) != 0) 162 printf("bouncing due alignment, paddr= 0x%lx, map= %p\n", (u_long)paddr, map); 163 if ((paddr & bndy) != (endaddr & bndy)) { 164 printf("bouncing due to boundary, paddr= 0x%lx, endaddr= 0x%lx, map= %p\n", (u_long)paddr, (u_long)endaddr, map); 165 printf("paddr & bndy = 0x%lx, paddr + len & bndy = 0x%lx\n", (u_long)(paddr & bndy), (u_long)(endaddr & bndy)); 166 } 167 retval = 1; 168 } 169 170 dmat = dmat->parent; 171 } while (retval == 0 && dmat != NULL); 172 return (retval); 173} 174 175/* 176 * Convenience function for manipulating driver locks from busdma (during 177 * busdma_swi, for example). Drivers that don't provide their own locks 178 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own 179 * non-mutex locking scheme don't have to use this at all. 180 */ 181void 182busdma_lock_mutex(void *arg, bus_dma_lock_op_t op) 183{ 184 struct mtx *dmtx; 185 186 dmtx = (struct mtx *)arg; 187 switch (op) { 188 case BUS_DMA_LOCK: 189 mtx_lock(dmtx); 190 break; 191 case BUS_DMA_UNLOCK: 192 mtx_unlock(dmtx); 193 break; 194 default: 195 panic("Unknown operation 0x%x for busdma_lock_mutex!", op); 196 } 197} 198 199/* 200 * dflt_lock should never get called. It gets put into the dma tag when 201 * lockfunc == NULL, which is only valid if the maps that are associated 202 * with the tag are meant to never be defered. 203 * XXX Should have a way to identify which driver is responsible here. 204 */ 205static void 206dflt_lock(void *arg, bus_dma_lock_op_t op) 207{ 208 panic("driver error: busdma dflt_lock called"); 209} 210 211#define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 212/* 213 * Allocate a device specific dma_tag. 214 */ 215int 216bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 217 bus_size_t boundary, bus_addr_t lowaddr, 218 bus_addr_t highaddr, bus_dma_filter_t *filter, 219 void *filterarg, bus_size_t maxsize, int nsegments, 220 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 221 void *lockfuncarg, bus_dma_tag_t *dmat) 222{ 223 bus_dma_tag_t newtag; 224 int error = 0; 225 226 /* Basic sanity checking */ 227 if (boundary != 0 && boundary < maxsegsz) 228 maxsegsz = boundary; 229 230 /* Return a NULL tag on failure */ 231 *dmat = NULL; 232 233 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, M_NOWAIT); 234 if (newtag == NULL) 235 return (ENOMEM); 236 237 STAILQ_INIT(&newtag->bounce_page_list); 238 newtag->parent = parent; 239 newtag->alignment = alignment; 240 newtag->boundary = boundary; 241 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 242 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + 243 (PAGE_SIZE - 1); 244 newtag->filter = filter; 245 newtag->filterarg = filterarg; 246 newtag->maxsize = maxsize; 247 newtag->nsegments = nsegments; 248 newtag->maxsegsz = maxsegsz; 249 newtag->flags = flags; 250 newtag->ref_count = 1; /* Count ourself */ 251 newtag->map_count = 0; 252 if (lockfunc != NULL) { 253 newtag->lockfunc = lockfunc; 254 newtag->lockfuncarg = lockfuncarg; 255 } else { 256 newtag->lockfunc = dflt_lock; 257 newtag->lockfuncarg = NULL; 258 } 259 newtag->segments = NULL; 260 261 /* Take into account any restrictions imposed by our parent tag */ 262 if (parent != NULL) { 263 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 264 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 265 /* 266 * XXX Not really correct??? Probably need to honor boundary 267 * all the way up the inheritence chain. 268 */ 269 newtag->boundary = MAX(parent->boundary, newtag->boundary); 270 if (newtag->filter == NULL) { 271 /* 272 * Short circuit looking at our parent directly 273 * since we have encapsulated all of its information 274 */ 275 newtag->filter = parent->filter; 276 newtag->filterarg = parent->filterarg; 277 newtag->parent = parent->parent; 278 } 279 if (newtag->parent != NULL) 280 atomic_add_int(&parent->ref_count, 1); 281 } 282 283 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) && 284 (flags & BUS_DMA_ALLOCNOW) != 0) { 285 /* Must bounce */ 286 287 if (lowaddr > bounce_lowaddr) { 288 /* 289 * Go through the pool and kill any pages 290 * that don't reside below lowaddr. 291 */ 292 panic("bus_dma_tag_create: page reallocation " 293 "not implemented"); 294 } 295 if (ptoa(total_bpages) < maxsize) { 296 int pages; 297 298 pages = atop(maxsize) - total_bpages; 299 300 /* Add pages to our bounce pool */ 301 if (alloc_bounce_pages(newtag, pages) < pages) 302 error = ENOMEM; 303 } 304 /* Performed initial allocation */ 305 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 306 } 307 308 if (error != 0) { 309 free(newtag, M_DEVBUF); 310 } else { 311 *dmat = newtag; 312 } 313 return (error); 314} 315 316int 317bus_dma_tag_destroy(bus_dma_tag_t dmat) 318{ 319 if (dmat != NULL) { 320 321 if (dmat->map_count != 0) 322 return (EBUSY); 323 324 while (dmat != NULL) { 325 bus_dma_tag_t parent; 326 327 parent = dmat->parent; 328 atomic_subtract_int(&dmat->ref_count, 1); 329 if (dmat->ref_count == 0) { 330 if (dmat->segments != NULL) 331 free(dmat->segments, M_DEVBUF); 332 free(dmat, M_DEVBUF); 333 /* 334 * Last reference count, so 335 * release our reference 336 * count on our parent. 337 */ 338 dmat = parent; 339 } else 340 dmat = NULL; 341 } 342 } 343 return (0); 344} 345 346/* 347 * Allocate a handle for mapping from kva/uva/physical 348 * address space into bus device space. 349 */ 350int 351bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 352{ 353 int error; 354 355 error = 0; 356 357 if (dmat->segments == NULL) { 358 dmat->segments = (bus_dma_segment_t *)malloc( 359 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 360 M_NOWAIT); 361 if (dmat->segments == NULL) 362 return (ENOMEM); 363 } 364 365 /* 366 * Bouncing might be required if the driver asks for an active 367 * exclusion region, a data alignment that is stricter than 1, and/or 368 * an active address boundary. 369 */ 370 if (dmat->lowaddr < ptoa((vm_paddr_t)Maxmem) 371 || dmat->alignment > 1 || dmat->boundary > 0) { 372 /* Must bounce */ 373 int maxpages; 374 375 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF, 376 M_NOWAIT | M_ZERO); 377 if (*mapp == NULL) 378 return (ENOMEM); 379 380 /* Initialize the new map */ 381 STAILQ_INIT(&((*mapp)->bpages)); 382 383 /* 384 * Attempt to add pages to our pool on a per-instance 385 * basis up to a sane limit. 386 */ 387 maxpages = MIN(MAX_BPAGES, Maxmem - atop(dmat->lowaddr)); 388 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 389 || (dmat->map_count > 0 && total_bpages < maxpages)) { 390 int pages; 391 392 if (dmat->lowaddr > bounce_lowaddr) { 393 /* 394 * Go through the pool and kill any pages 395 * that don't reside below lowaddr. 396 */ 397 panic("bus_dmamap_create: page reallocation " 398 "not implemented"); 399 } 400 pages = MAX(atop(dmat->maxsize), 1); 401 pages = MIN(maxpages - total_bpages, pages); 402 if (alloc_bounce_pages(dmat, pages) < pages) 403 error = ENOMEM; 404 405 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 406 if (error == 0) 407 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 408 } else { 409 error = 0; 410 } 411 } 412 } else { 413 *mapp = NULL; 414 } 415 if (error == 0) 416 dmat->map_count++; 417 return (error); 418} 419 420/* 421 * Destroy a handle for mapping from kva/uva/physical 422 * address space into bus device space. 423 */ 424int 425bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 426{ 427 if (map != NULL && map != &nobounce_dmamap) { 428 if (STAILQ_FIRST(&map->bpages) != NULL) 429 return (EBUSY); 430 free(map, M_DEVBUF); 431 } 432 dmat->map_count--; 433 return (0); 434} 435 436 437/* 438 * Allocate a piece of memory that can be efficiently mapped into 439 * bus device space based on the constraints lited in the dma tag. 440 * A dmamap to for use with dmamap_load is also allocated. 441 */ 442int 443bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 444 bus_dmamap_t *mapp) 445{ 446 int mflags; 447 448 if (flags & BUS_DMA_NOWAIT) 449 mflags = M_NOWAIT; 450 else 451 mflags = M_WAITOK; 452 if (flags & BUS_DMA_ZERO) 453 mflags |= M_ZERO; 454 455 /* If we succeed, no mapping/bouncing will be required */ 456 *mapp = NULL; 457 458 if (dmat->segments == NULL) { 459 dmat->segments = (bus_dma_segment_t *)malloc( 460 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 461 M_NOWAIT); 462 if (dmat->segments == NULL) 463 return (ENOMEM); 464 } 465 466 if ((dmat->maxsize <= PAGE_SIZE) && 467 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) { 468 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags); 469 } else { 470 /* 471 * XXX Use Contigmalloc until it is merged into this facility 472 * and handles multi-seg allocations. Nobody is doing 473 * multi-seg allocations yet though. 474 * XXX Certain AGP hardware does. 475 */ 476 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 477 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul, 478 dmat->boundary); 479 } 480 if (*vaddr == NULL) 481 return (ENOMEM); 482 return (0); 483} 484 485/* 486 * Free a piece of memory and it's allociated dmamap, that was allocated 487 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 488 */ 489void 490bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 491{ 492 /* 493 * dmamem does not need to be bounced, so the map should be 494 * NULL 495 */ 496 if (map != NULL) 497 panic("bus_dmamem_free: Invalid map freed\n"); 498 if ((dmat->maxsize <= PAGE_SIZE) 499 && dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) 500 free(vaddr, M_DEVBUF); 501 else { 502 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 503 } 504} 505 506/* 507 * Utility function to load a linear buffer. lastaddrp holds state 508 * between invocations (for multiple-buffer loads). segp contains 509 * the starting segment on entrace, and the ending segment on exit. 510 * first indicates if this is the first invocation of this function. 511 */ 512static int 513_bus_dmamap_load_buffer(bus_dma_tag_t dmat, 514 bus_dmamap_t map, 515 void *buf, bus_size_t buflen, 516 struct thread *td, 517 int flags, 518 bus_addr_t *lastaddrp, 519 int *segp, 520 int first) 521{ 522 bus_dma_segment_t *segs; 523 bus_size_t sgsize; 524 bus_addr_t curaddr, lastaddr, baddr, bmask; 525 vm_offset_t vaddr; 526 bus_addr_t paddr; 527 int needbounce = 0; 528 int seg; 529 pmap_t pmap; 530 531 segs = dmat->segments; 532 533 if (map == NULL) 534 map = &nobounce_dmamap; 535 536 if (td != NULL) 537 pmap = vmspace_pmap(td->td_proc->p_vmspace); 538 else 539 pmap = NULL; 540 541 if ((dmat->lowaddr < ptoa((vm_paddr_t)Maxmem) 542 || dmat->boundary > 0 || dmat->alignment > 1) 543 && map != &nobounce_dmamap && map->pagesneeded == 0) { 544 vm_offset_t vendaddr; 545 546 /* 547 * Count the number of bounce pages 548 * needed in order to complete this transfer 549 */ 550 vaddr = trunc_page((vm_offset_t)buf); 551 vendaddr = (vm_offset_t)buf + buflen; 552 553 while (vaddr < vendaddr) { 554 paddr = pmap_kextract(vaddr); 555 if (run_filter(dmat, paddr, PAGE_SIZE, map) != 0) { 556 needbounce = 1; 557 map->pagesneeded++; 558 } 559 vaddr += PAGE_SIZE; 560 } 561 } 562 563 vaddr = (vm_offset_t)buf; 564 565 /* Reserve Necessary Bounce Pages */ 566 if (map->pagesneeded != 0) { 567 mtx_lock(&bounce_lock); 568 if (flags & BUS_DMA_NOWAIT) { 569 if (reserve_bounce_pages(dmat, map, 0) != 0) { 570 mtx_unlock(&bounce_lock); 571 return (ENOMEM); 572 } 573 } else { 574 if (reserve_bounce_pages(dmat, map, 1) != 0) { 575 /* 576 * Queue us for resources. A future 577 * optimization might be to search other bounce 578 * lists for extra pages. 579 */ 580 map->dmat = dmat; 581 map->buf = buf; 582 map->buflen = buflen; 583 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, 584 map, links); 585 mtx_unlock(&bounce_lock); 586 return (EINPROGRESS); 587 } 588 } 589 mtx_unlock(&bounce_lock); 590 } 591 592 lastaddr = *lastaddrp; 593 bmask = ~(dmat->boundary - 1); 594 595 for (seg = *segp; buflen > 0 ; ) { 596 /* 597 * Get the physical address for this segment. 598 */ 599 if (pmap) 600 curaddr = pmap_extract(pmap, vaddr); 601 else 602 curaddr = pmap_kextract(vaddr); 603 604 /* 605 * Compute the segment size, and adjust counts. 606 */ 607 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK); 608 if (buflen < sgsize) 609 sgsize = buflen; 610 611 /* 612 * Make sure we don't cross any boundaries. 613 */ 614 if (dmat->boundary > 0) { 615 baddr = (curaddr + dmat->boundary) & bmask; 616 if (sgsize > (baddr - curaddr)) 617 sgsize = (baddr - curaddr); 618 } 619 620 if (map->pagesneeded != 0 && run_filter(dmat, curaddr, sgsize, map)) 621 curaddr = add_bounce_page(dmat, map, vaddr, sgsize); 622 623 /* 624 * Insert chunk into a segment, coalescing with 625 * previous segment if possible. 626 */ 627 if (first) { 628 segs[seg].ds_addr = curaddr; 629 segs[seg].ds_len = sgsize; 630 first = 0; 631 } else { 632 if (needbounce == 0 && curaddr == lastaddr && 633 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz && 634 (dmat->boundary == 0 || 635 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 636 segs[seg].ds_len += sgsize; 637 else { 638 if (++seg >= dmat->nsegments) 639 break; 640 segs[seg].ds_addr = curaddr; 641 segs[seg].ds_len = sgsize; 642 } 643 } 644 645 lastaddr = curaddr + sgsize; 646 vaddr += sgsize; 647 buflen -= sgsize; 648 } 649 650 *segp = seg; 651 *lastaddrp = lastaddr; 652 653 /* 654 * Did we fit? 655 */ 656 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 657} 658 659/* 660 * Map the buffer buf into bus space using the dmamap map. 661 */ 662int 663bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 664 bus_size_t buflen, bus_dmamap_callback_t *callback, 665 void *callback_arg, int flags) 666{ 667 bus_addr_t lastaddr = 0; 668 int error, nsegs = 0; 669 670 if (map != NULL) { 671 flags |= BUS_DMA_WAITOK; 672 map->callback = callback; 673 map->callback_arg = callback_arg; 674 } 675 676 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags, 677 &lastaddr, &nsegs, 1); 678 679 if (error == EINPROGRESS) 680 return (error); 681 682 if (error) 683 (*callback)(callback_arg, dmat->segments, 0, error); 684 else 685 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0); 686 687 return (0); 688} 689 690 691/* 692 * Like _bus_dmamap_load(), but for mbufs. 693 */ 694int 695bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 696 struct mbuf *m0, 697 bus_dmamap_callback2_t *callback, void *callback_arg, 698 int flags) 699{ 700 int nsegs, error; 701 702 M_ASSERTPKTHDR(m0); 703 704 flags |= BUS_DMA_NOWAIT; 705 nsegs = 0; 706 error = 0; 707 if (m0->m_pkthdr.len <= dmat->maxsize) { 708 int first = 1; 709 bus_addr_t lastaddr = 0; 710 struct mbuf *m; 711 712 for (m = m0; m != NULL && error == 0; m = m->m_next) { 713 if (m->m_len > 0) { 714 error = _bus_dmamap_load_buffer(dmat, map, 715 m->m_data, m->m_len, 716 NULL, flags, &lastaddr, 717 &nsegs, first); 718 first = 0; 719 } 720 } 721 } else { 722 error = EINVAL; 723 } 724 725 if (error) { 726 /* force "no valid mappings" in callback */ 727 (*callback)(callback_arg, dmat->segments, 0, 0, error); 728 } else { 729 (*callback)(callback_arg, dmat->segments, 730 nsegs+1, m0->m_pkthdr.len, error); 731 } 732 return (error); 733} 734 735/* 736 * Like _bus_dmamap_load(), but for uios. 737 */ 738int 739bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 740 struct uio *uio, 741 bus_dmamap_callback2_t *callback, void *callback_arg, 742 int flags) 743{ 744 bus_addr_t lastaddr; 745 int nsegs, error, first, i; 746 bus_size_t resid; 747 struct iovec *iov; 748 struct thread *td = NULL; 749 750 flags |= BUS_DMA_NOWAIT; 751 resid = uio->uio_resid; 752 iov = uio->uio_iov; 753 754 if (uio->uio_segflg == UIO_USERSPACE) { 755 td = uio->uio_td; 756 KASSERT(td != NULL, 757 ("bus_dmamap_load_uio: USERSPACE but no proc")); 758 } 759 760 nsegs = 0; 761 error = 0; 762 first = 1; 763 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 764 /* 765 * Now at the first iovec to load. Load each iovec 766 * until we have exhausted the residual count. 767 */ 768 bus_size_t minlen = 769 resid < iov[i].iov_len ? resid : iov[i].iov_len; 770 caddr_t addr = (caddr_t) iov[i].iov_base; 771 772 if (minlen > 0) { 773 error = _bus_dmamap_load_buffer(dmat, map, 774 addr, minlen, 775 td, flags, &lastaddr, &nsegs, first); 776 first = 0; 777 778 resid -= minlen; 779 } 780 } 781 782 if (error) { 783 /* force "no valid mappings" in callback */ 784 (*callback)(callback_arg, dmat->segments, 0, 0, error); 785 } else { 786 (*callback)(callback_arg, dmat->segments, 787 nsegs+1, uio->uio_resid, error); 788 } 789 return (error); 790} 791 792/* 793 * Release the mapping held by map. 794 */ 795void 796_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 797{ 798 struct bounce_page *bpage; 799 800 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 801 STAILQ_REMOVE_HEAD(&map->bpages, links); 802 free_bounce_page(dmat, bpage); 803 } 804} 805 806void 807_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 808{ 809 struct bounce_page *bpage; 810 811 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 812 /* 813 * Handle data bouncing. We might also 814 * want to add support for invalidating 815 * the caches on broken hardware 816 */ 817 total_bounced++; 818 819 if (op & BUS_DMASYNC_PREWRITE) { 820 while (bpage != NULL) { 821 bcopy((void *)bpage->datavaddr, 822 (void *)bpage->vaddr, 823 bpage->datacount); 824 bpage = STAILQ_NEXT(bpage, links); 825 } 826 } 827 828 if (op & BUS_DMASYNC_POSTREAD) { 829 while (bpage != NULL) { 830 bcopy((void *)bpage->vaddr, 831 (void *)bpage->datavaddr, 832 bpage->datacount); 833 bpage = STAILQ_NEXT(bpage, links); 834 } 835 } 836 } 837} 838 839static void 840init_bounce_pages(void *dummy __unused) 841{ 842 843 free_bpages = 0; 844 reserved_bpages = 0; 845 active_bpages = 0; 846 total_bpages = 0; 847 STAILQ_INIT(&bounce_map_waitinglist); 848 STAILQ_INIT(&bounce_map_callbacklist); 849 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 850} 851SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 852 853static int 854alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 855{ 856 int count; 857 858 count = 0; 859 while (numpages > 0) { 860 struct bounce_page *bpage; 861 862 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 863 M_NOWAIT | M_ZERO); 864 865 if (bpage == NULL) 866 break; 867 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 868 M_NOWAIT, 0ul, 869 dmat->lowaddr, 870 dmat->alignment? 871 dmat->alignment : 1ul, 872 dmat->boundary); 873 if (bpage->vaddr == 0) { 874 free(bpage, M_DEVBUF); 875 break; 876 } 877 bpage->busaddr = pmap_kextract(bpage->vaddr); 878 mtx_lock(&bounce_lock); 879 STAILQ_INSERT_TAIL(&dmat->bounce_page_list, bpage, links); 880 total_bpages++; 881 free_bpages++; 882 mtx_unlock(&bounce_lock); 883 count++; 884 numpages--; 885 } 886 return (count); 887} 888 889static int 890reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 891{ 892 int pages; 893 894 mtx_assert(&bounce_lock, MA_OWNED); 895 pages = MIN(free_bpages, map->pagesneeded - map->pagesreserved); 896 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 897 return (map->pagesneeded - (map->pagesreserved + pages)); 898 free_bpages -= pages; 899 reserved_bpages += pages; 900 map->pagesreserved += pages; 901 pages = map->pagesneeded - map->pagesreserved; 902 903 return (pages); 904} 905 906static bus_addr_t 907add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 908 bus_size_t size) 909{ 910 struct bounce_page *bpage; 911 912 KASSERT(map != NULL && map != &nobounce_dmamap, 913 ("add_bounce_page: bad map %p", map)); 914 915 if (map->pagesneeded == 0) 916 panic("add_bounce_page: map doesn't need any pages"); 917 map->pagesneeded--; 918 919 if (map->pagesreserved == 0) 920 panic("add_bounce_page: map doesn't need any pages"); 921 map->pagesreserved--; 922 923 mtx_lock(&bounce_lock); 924 bpage = STAILQ_FIRST(&dmat->bounce_page_list); 925 if (bpage == NULL) 926 panic("add_bounce_page: free page list is empty"); 927 928 STAILQ_REMOVE_HEAD(&dmat->bounce_page_list, links); 929 reserved_bpages--; 930 active_bpages++; 931 mtx_unlock(&bounce_lock); 932 933 bpage->datavaddr = vaddr; 934 bpage->datacount = size; 935 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 936 return (bpage->busaddr); 937} 938 939static void 940free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 941{ 942 struct bus_dmamap *map; 943 944 bpage->datavaddr = 0; 945 bpage->datacount = 0; 946 947 mtx_lock(&bounce_lock); 948 STAILQ_INSERT_HEAD(&dmat->bounce_page_list, bpage, links); 949 free_bpages++; 950 active_bpages--; 951 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 952 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 953 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 954 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 955 map, links); 956 busdma_swi_pending = 1; 957 total_deferred++; 958 swi_sched(vm_ih, 0); 959 } 960 } 961 mtx_unlock(&bounce_lock); 962} 963 964void 965busdma_swi(void) 966{ 967 bus_dma_tag_t dmat; 968 struct bus_dmamap *map; 969 970 mtx_lock(&bounce_lock); 971 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 972 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 973 mtx_unlock(&bounce_lock); 974 dmat = map->dmat; 975 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK); 976 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 977 map->callback, map->callback_arg, /*flags*/0); 978 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK); 979 mtx_lock(&bounce_lock); 980 } 981 mtx_unlock(&bounce_lock); 982} 983