busdma_machdep.c revision 137142
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 137142 2004-11-02 23:52:58Z 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/ktr.h> 37#include <sys/lock.h> 38#include <sys/proc.h> 39#include <sys/mutex.h> 40#include <sys/mbuf.h> 41#include <sys/uio.h> 42#include <sys/sysctl.h> 43#include <sys/ktr.h> 44 45#include <vm/vm.h> 46#include <vm/vm_page.h> 47#include <vm/vm_map.h> 48 49#include <machine/atomic.h> 50#include <machine/bus.h> 51#include <machine/md_var.h> 52 53#define MAX_BPAGES 512 54 55struct bus_dma_tag { 56 bus_dma_tag_t parent; 57 bus_size_t alignment; 58 bus_size_t boundary; 59 bus_addr_t lowaddr; 60 bus_addr_t highaddr; 61 bus_dma_filter_t *filter; 62 void *filterarg; 63 bus_size_t maxsize; 64 u_int nsegments; 65 bus_size_t maxsegsz; 66 int flags; 67 int ref_count; 68 int map_count; 69 bus_dma_lock_t *lockfunc; 70 void *lockfuncarg; 71 bus_dma_segment_t *segments; 72}; 73 74struct bounce_page { 75 vm_offset_t vaddr; /* kva of bounce buffer */ 76 bus_addr_t busaddr; /* Physical address */ 77 vm_offset_t datavaddr; /* kva of client data */ 78 bus_size_t datacount; /* client data count */ 79 STAILQ_ENTRY(bounce_page) links; 80}; 81 82int busdma_swi_pending; 83 84static struct mtx bounce_lock; 85static STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 86static int free_bpages; 87static int reserved_bpages; 88static int active_bpages; 89static int total_bpages; 90static int total_bounced; 91static int total_deferred; 92static bus_addr_t bounce_lowaddr = BUS_SPACE_MAXADDR; 93 94SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 95SYSCTL_INT(_hw_busdma, OID_AUTO, free_bpages, CTLFLAG_RD, &free_bpages, 0, 96 "Free bounce pages"); 97SYSCTL_INT(_hw_busdma, OID_AUTO, reserved_bpages, CTLFLAG_RD, &reserved_bpages, 98 0, "Reserved bounce pages"); 99SYSCTL_INT(_hw_busdma, OID_AUTO, active_bpages, CTLFLAG_RD, &active_bpages, 0, 100 "Active bounce pages"); 101SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 102 "Total bounce pages"); 103SYSCTL_INT(_hw_busdma, OID_AUTO, total_bounced, CTLFLAG_RD, &total_bounced, 0, 104 "Total bounce requests"); 105SYSCTL_INT(_hw_busdma, OID_AUTO, total_deferred, CTLFLAG_RD, &total_deferred, 0, 106 "Total bounce requests that were deferred"); 107 108struct bus_dmamap { 109 struct bp_list bpages; 110 int pagesneeded; 111 int pagesreserved; 112 bus_dma_tag_t dmat; 113 void *buf; /* unmapped buffer pointer */ 114 bus_size_t buflen; /* unmapped buffer length */ 115 bus_dmamap_callback_t *callback; 116 void *callback_arg; 117 STAILQ_ENTRY(bus_dmamap) links; 118}; 119 120static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 121static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 122static struct bus_dmamap nobounce_dmamap; 123 124static void init_bounce_pages(void *dummy); 125static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 126static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 127 int commit); 128static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 129 vm_offset_t vaddr, bus_size_t size); 130static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 131static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr, 132 bus_size_t len); 133 134/* 135 * Return true if a match is made. 136 * 137 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'. 138 * 139 * If paddr is within the bounds of the dma tag then call the filter callback 140 * to check for a match, if there is no filter callback then assume a match. 141 */ 142static __inline int 143run_filter(bus_dma_tag_t dmat, bus_addr_t paddr, bus_size_t len) 144{ 145 bus_size_t bndy; 146 int retval; 147 148 retval = 0; 149 bndy = dmat->boundary; 150 151 do { 152 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) 153 || ((paddr & (dmat->alignment - 1)) != 0) 154 || ((paddr & bndy) != ((paddr + len) & bndy))) 155 && (dmat->filter == NULL 156 || (*dmat->filter)(dmat->filterarg, paddr) != 0)) 157 retval = 1; 158 159 dmat = dmat->parent; 160 } while (retval == 0 && dmat != NULL); 161 return (retval); 162} 163 164/* 165 * Convenience function for manipulating driver locks from busdma (during 166 * busdma_swi, for example). Drivers that don't provide their own locks 167 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own 168 * non-mutex locking scheme don't have to use this at all. 169 */ 170void 171busdma_lock_mutex(void *arg, bus_dma_lock_op_t op) 172{ 173 struct mtx *dmtx; 174 175 dmtx = (struct mtx *)arg; 176 switch (op) { 177 case BUS_DMA_LOCK: 178 mtx_lock(dmtx); 179 break; 180 case BUS_DMA_UNLOCK: 181 mtx_unlock(dmtx); 182 break; 183 default: 184 panic("Unknown operation 0x%x for busdma_lock_mutex!", op); 185 } 186} 187 188/* 189 * dflt_lock should never get called. It gets put into the dma tag when 190 * lockfunc == NULL, which is only valid if the maps that are associated 191 * with the tag are meant to never be defered. 192 * XXX Should have a way to identify which driver is responsible here. 193 */ 194static void 195dflt_lock(void *arg, bus_dma_lock_op_t op) 196{ 197 panic("driver error: busdma dflt_lock called"); 198} 199 200#define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 201/* 202 * Allocate a device specific dma_tag. 203 */ 204int 205bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 206 bus_size_t boundary, bus_addr_t lowaddr, 207 bus_addr_t highaddr, bus_dma_filter_t *filter, 208 void *filterarg, bus_size_t maxsize, int nsegments, 209 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 210 void *lockfuncarg, bus_dma_tag_t *dmat) 211{ 212 bus_dma_tag_t newtag; 213 int error = 0; 214 215 /* Basic sanity checking */ 216 if (boundary != 0 && boundary < maxsegsz) 217 maxsegsz = boundary; 218 219 /* Return a NULL tag on failure */ 220 *dmat = NULL; 221 222 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, M_NOWAIT); 223 if (newtag == NULL) { 224 CTR3(KTR_BUSDMA, "bus_dma_tag_create returned tag %p tag " 225 "flags 0x%x error %d", newtag, 0, error); 226 return (ENOMEM); 227 } 228 229 newtag->parent = parent; 230 newtag->alignment = alignment; 231 newtag->boundary = boundary; 232 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 233 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + 234 (PAGE_SIZE - 1); 235 newtag->filter = filter; 236 newtag->filterarg = filterarg; 237 newtag->maxsize = maxsize; 238 newtag->nsegments = nsegments; 239 newtag->maxsegsz = maxsegsz; 240 newtag->flags = flags; 241 newtag->ref_count = 1; /* Count ourself */ 242 newtag->map_count = 0; 243 if (lockfunc != NULL) { 244 newtag->lockfunc = lockfunc; 245 newtag->lockfuncarg = lockfuncarg; 246 } else { 247 newtag->lockfunc = dflt_lock; 248 newtag->lockfuncarg = NULL; 249 } 250 newtag->segments = NULL; 251 252 /* Take into account any restrictions imposed by our parent tag */ 253 if (parent != NULL) { 254 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 255 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 256 if (newtag->boundary == 0) 257 newtag->boundary = parent->boundary; 258 else if (parent->boundary != 0) 259 newtag->boundary = MIN(parent->boundary, 260 newtag->boundary); 261 if (newtag->filter == NULL) { 262 /* 263 * Short circuit looking at our parent directly 264 * since we have encapsulated all of its information 265 */ 266 newtag->filter = parent->filter; 267 newtag->filterarg = parent->filterarg; 268 newtag->parent = parent->parent; 269 } 270 if (newtag->parent != NULL) 271 atomic_add_int(&parent->ref_count, 1); 272 } 273 274 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) && 275 (flags & BUS_DMA_ALLOCNOW) != 0) { 276 /* Must bounce */ 277 278 if (lowaddr > bounce_lowaddr) { 279 /* 280 * Go through the pool and kill any pages 281 * that don't reside below lowaddr. 282 */ 283 panic("bus_dma_tag_create: page reallocation " 284 "not implemented"); 285 } 286 if (ptoa(total_bpages) < maxsize) { 287 int pages; 288 289 pages = atop(maxsize) - total_bpages; 290 291 /* Add pages to our bounce pool */ 292 if (alloc_bounce_pages(newtag, pages) < pages) 293 error = ENOMEM; 294 } 295 /* Performed initial allocation */ 296 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 297 } 298 299 if (error != 0) { 300 free(newtag, M_DEVBUF); 301 } else { 302 *dmat = newtag; 303 } 304 CTR3(KTR_BUSDMA, "bus_dma_tag_create returned tag %p tag flags 0x%x " 305 "error %d", newtag, (newtag != NULL ? newtag->flags : 0), error); 306 return (error); 307} 308 309int 310bus_dma_tag_destroy(bus_dma_tag_t dmat) 311{ 312 bus_dma_tag_t dmat_copy; 313 int error; 314 315 error = 0; 316 dmat_copy = dmat; 317 318 if (dmat != NULL) { 319 320 if (dmat->map_count != 0) { 321 error = EBUSY; 322 goto out; 323 } 324 325 while (dmat != NULL) { 326 bus_dma_tag_t parent; 327 328 parent = dmat->parent; 329 atomic_subtract_int(&dmat->ref_count, 1); 330 if (dmat->ref_count == 0) { 331 if (dmat->segments != NULL) 332 free(dmat->segments, M_DEVBUF); 333 free(dmat, M_DEVBUF); 334 /* 335 * Last reference count, so 336 * release our reference 337 * count on our parent. 338 */ 339 dmat = parent; 340 } else 341 dmat = NULL; 342 } 343 } 344out: 345 CTR2(KTR_BUSDMA, "bus_dma_tag_destroy tag %p error %d", dmat_copy, 346 error); 347 return (error); 348} 349 350/* 351 * Allocate a handle for mapping from kva/uva/physical 352 * address space into bus device space. 353 */ 354int 355bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 356{ 357 int error; 358 359 error = 0; 360 361 if (dmat->segments == NULL) { 362 dmat->segments = (bus_dma_segment_t *)malloc( 363 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 364 M_NOWAIT); 365 if (dmat->segments == NULL) { 366 CTR2(KTR_BUSDMA, "bus_dmamap_create: tag %p error %d", 367 dmat, ENOMEM); 368 return (ENOMEM); 369 } 370 } 371 372 /* 373 * Bouncing might be required if the driver asks for an active 374 * exclusion region, a data alignment that is stricter than 1, and/or 375 * an active address boundary. 376 */ 377 if (dmat->lowaddr < ptoa((vm_paddr_t)Maxmem) 378 || dmat->alignment > 1 || dmat->boundary > 0) { 379 /* Must bounce */ 380 int maxpages; 381 382 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF, 383 M_NOWAIT | M_ZERO); 384 if (*mapp == NULL) { 385 CTR2(KTR_BUSDMA, "bus_dmamap_create: tag %p error %d", 386 dmat, ENOMEM); 387 return (ENOMEM); 388 } 389 390 /* Initialize the new map */ 391 STAILQ_INIT(&((*mapp)->bpages)); 392 393 /* 394 * Attempt to add pages to our pool on a per-instance 395 * basis up to a sane limit. 396 */ 397 maxpages = MIN(MAX_BPAGES, Maxmem - atop(dmat->lowaddr)); 398 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 399 || (dmat->map_count > 0 && total_bpages < maxpages)) { 400 int pages; 401 402 if (dmat->lowaddr > bounce_lowaddr) { 403 /* 404 * Go through the pool and kill any pages 405 * that don't reside below lowaddr. 406 */ 407 panic("bus_dmamap_create: page reallocation " 408 "not implemented"); 409 } 410 pages = MAX(atop(dmat->maxsize), 1); 411 pages = MIN(maxpages - total_bpages, pages); 412 if (alloc_bounce_pages(dmat, pages) < pages) 413 error = ENOMEM; 414 415 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 416 if (error == 0) 417 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 418 } else { 419 error = 0; 420 } 421 } 422 } else { 423 *mapp = NULL; 424 } 425 if (error == 0) 426 dmat->map_count++; 427 CTR3(KTR_BUSDMA, "bus_dmamap_create: tag %p tag flags 0x%x error %d", 428 dmat, dmat->flags, error); 429 return (error); 430} 431 432/* 433 * Destroy a handle for mapping from kva/uva/physical 434 * address space into bus device space. 435 */ 436int 437bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 438{ 439 if (map != NULL && map != &nobounce_dmamap) { 440 if (STAILQ_FIRST(&map->bpages) != NULL) { 441 CTR2(KTR_BUSDMA, "bus_dmamap_destroy: tag %p error %d", 442 dmat, EBUSY); 443 return (EBUSY); 444 } 445 free(map, M_DEVBUF); 446 } 447 dmat->map_count--; 448 CTR1(KTR_BUSDMA, "bus_dmamap_destroy: tag %p error 0", dmat); 449 return (0); 450} 451 452 453/* 454 * Allocate a piece of memory that can be efficiently mapped into 455 * bus device space based on the constraints lited in the dma tag. 456 * A dmamap to for use with dmamap_load is also allocated. 457 */ 458int 459bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 460 bus_dmamap_t *mapp) 461{ 462 int mflags; 463 464 if (flags & BUS_DMA_NOWAIT) 465 mflags = M_NOWAIT; 466 else 467 mflags = M_WAITOK; 468 if (flags & BUS_DMA_ZERO) 469 mflags |= M_ZERO; 470 471 /* If we succeed, no mapping/bouncing will be required */ 472 *mapp = NULL; 473 474 if (dmat->segments == NULL) { 475 dmat->segments = (bus_dma_segment_t *)malloc( 476 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 477 M_NOWAIT); 478 if (dmat->segments == NULL) { 479 CTR3(KTR_BUSDMA, "bus_dmamem_alloc: tag %p tag " 480 "flags 0x%x error %d", dmat, dmat->flags, ENOMEM); 481 return (ENOMEM); 482 } 483 } 484 485 if ((dmat->maxsize <= PAGE_SIZE) && 486 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) { 487 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags); 488 } else { 489 /* 490 * XXX Use Contigmalloc until it is merged into this facility 491 * and handles multi-seg allocations. Nobody is doing 492 * multi-seg allocations yet though. 493 * XXX Certain AGP hardware does. 494 */ 495 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 496 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul, 497 dmat->boundary); 498 } 499 if (*vaddr == NULL) { 500 CTR3(KTR_BUSDMA, "bus_dmamem_alloc: tag %p tag flags 0x%x " 501 "error %d", dmat, dmat->flags, ENOMEM); 502 return (ENOMEM); 503 } 504 CTR3(KTR_BUSDMA, "bus_dmamem_alloc: tag %p tag flags 0x%x error %d", 505 dmat, dmat->flags, ENOMEM); 506 return (0); 507} 508 509/* 510 * Free a piece of memory and it's allociated dmamap, that was allocated 511 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 512 */ 513void 514bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 515{ 516 /* 517 * dmamem does not need to be bounced, so the map should be 518 * NULL 519 */ 520 if (map != NULL) 521 panic("bus_dmamem_free: Invalid map freed\n"); 522 if ((dmat->maxsize <= PAGE_SIZE) 523 && dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) 524 free(vaddr, M_DEVBUF); 525 else { 526 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 527 } 528 CTR2(KTR_BUSDMA, "bus_dmamem_free: tag %p flags 0x%x", dmat, 529 dmat->flags); 530} 531 532/* 533 * Utility function to load a linear buffer. lastaddrp holds state 534 * between invocations (for multiple-buffer loads). segp contains 535 * the starting segment on entrace, and the ending segment on exit. 536 * first indicates if this is the first invocation of this function. 537 */ 538static __inline int 539_bus_dmamap_load_buffer(bus_dma_tag_t dmat, 540 bus_dmamap_t map, 541 void *buf, bus_size_t buflen, 542 pmap_t pmap, 543 int flags, 544 bus_addr_t *lastaddrp, 545 int *segp, 546 int first) 547{ 548 bus_dma_segment_t *segs; 549 bus_size_t sgsize; 550 bus_addr_t curaddr, lastaddr, baddr, bmask; 551 vm_offset_t vaddr; 552 bus_addr_t paddr; 553 int needbounce = 0; 554 int seg; 555 556 segs = dmat->segments; 557 558 if (map == NULL) 559 map = &nobounce_dmamap; 560 561 if ((map != &nobounce_dmamap && map->pagesneeded == 0) 562 && (dmat->lowaddr < ptoa((vm_paddr_t)Maxmem) 563 || dmat->boundary > 0 || dmat->alignment > 1)) { 564 vm_offset_t vendaddr; 565 566 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 567 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem), 568 dmat->boundary, dmat->alignment); 569 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 570 map, &nobounce_dmamap, map->pagesneeded); 571 /* 572 * Count the number of bounce pages 573 * needed in order to complete this transfer 574 */ 575 vaddr = trunc_page((vm_offset_t)buf); 576 vendaddr = (vm_offset_t)buf + buflen; 577 578 while (vaddr < vendaddr) { 579 paddr = pmap_kextract(vaddr); 580 if (run_filter(dmat, paddr, 0) != 0) { 581 needbounce = 1; 582 map->pagesneeded++; 583 } 584 vaddr += PAGE_SIZE; 585 } 586 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 587 } 588 589 /* Reserve Necessary Bounce Pages */ 590 if (map->pagesneeded != 0) { 591 mtx_lock(&bounce_lock); 592 if (flags & BUS_DMA_NOWAIT) { 593 if (reserve_bounce_pages(dmat, map, 0) != 0) { 594 mtx_unlock(&bounce_lock); 595 return (ENOMEM); 596 } 597 } else { 598 if (reserve_bounce_pages(dmat, map, 1) != 0) { 599 /* Queue us for resources */ 600 map->dmat = dmat; 601 map->buf = buf; 602 map->buflen = buflen; 603 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, 604 map, links); 605 mtx_unlock(&bounce_lock); 606 return (EINPROGRESS); 607 } 608 } 609 mtx_unlock(&bounce_lock); 610 } 611 612 vaddr = (vm_offset_t)buf; 613 lastaddr = *lastaddrp; 614 bmask = ~(dmat->boundary - 1); 615 616 for (seg = *segp; buflen > 0 ; ) { 617 /* 618 * Get the physical address for this segment. 619 */ 620 if (pmap) 621 curaddr = pmap_extract(pmap, vaddr); 622 else 623 curaddr = pmap_kextract(vaddr); 624 625 /* 626 * Compute the segment size, and adjust counts. 627 */ 628 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK); 629 if (buflen < sgsize) 630 sgsize = buflen; 631 632 /* 633 * Make sure we don't cross any boundaries. 634 */ 635 if (dmat->boundary > 0) { 636 baddr = (curaddr + dmat->boundary) & bmask; 637 if (sgsize > (baddr - curaddr)) 638 sgsize = (baddr - curaddr); 639 } 640 641 if (map->pagesneeded != 0 && run_filter(dmat, curaddr, sgsize)) 642 curaddr = add_bounce_page(dmat, map, vaddr, sgsize); 643 644 /* 645 * Insert chunk into a segment, coalescing with 646 * previous segment if possible. 647 */ 648 if (first) { 649 segs[seg].ds_addr = curaddr; 650 segs[seg].ds_len = sgsize; 651 first = 0; 652 } else { 653 if (needbounce == 0 && curaddr == lastaddr && 654 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz && 655 (dmat->boundary == 0 || 656 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 657 segs[seg].ds_len += sgsize; 658 else { 659 if (++seg >= dmat->nsegments) 660 break; 661 segs[seg].ds_addr = curaddr; 662 segs[seg].ds_len = sgsize; 663 } 664 } 665 666 lastaddr = curaddr + sgsize; 667 vaddr += sgsize; 668 buflen -= sgsize; 669 } 670 671 *segp = seg; 672 *lastaddrp = lastaddr; 673 674 /* 675 * Did we fit? 676 */ 677 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 678} 679 680/* 681 * Map the buffer buf into bus space using the dmamap map. 682 */ 683int 684bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 685 bus_size_t buflen, bus_dmamap_callback_t *callback, 686 void *callback_arg, int flags) 687{ 688 bus_addr_t lastaddr = 0; 689 int error, nsegs = 0; 690 691 if (map != NULL) { 692 flags |= BUS_DMA_WAITOK; 693 map->callback = callback; 694 map->callback_arg = callback_arg; 695 } 696 697 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags, 698 &lastaddr, &nsegs, 1); 699 700 if (error == EINPROGRESS) { 701 CTR3(KTR_BUSDMA, "bus_dmamap_load: tag %p tag flags 0x%x " 702 "error %d", dmat, dmat->flags, error); 703 return (error); 704 } 705 706 if (error) 707 (*callback)(callback_arg, dmat->segments, 0, error); 708 else 709 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0); 710 711 CTR2(KTR_BUSDMA, "bus_dmamap_load: tag %p tag flags 0x%x error 0", 712 dmat, dmat->flags); 713 return (0); 714} 715 716 717/* 718 * Like _bus_dmamap_load(), but for mbufs. 719 */ 720int 721bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 722 struct mbuf *m0, 723 bus_dmamap_callback2_t *callback, void *callback_arg, 724 int flags) 725{ 726 int nsegs, error; 727 728 M_ASSERTPKTHDR(m0); 729 730 flags |= BUS_DMA_NOWAIT; 731 nsegs = 0; 732 error = 0; 733 if (m0->m_pkthdr.len <= dmat->maxsize) { 734 int first = 1; 735 bus_addr_t lastaddr = 0; 736 struct mbuf *m; 737 738 for (m = m0; m != NULL && error == 0; m = m->m_next) { 739 if (m->m_len > 0) { 740 error = _bus_dmamap_load_buffer(dmat, map, 741 m->m_data, m->m_len, 742 NULL, flags, &lastaddr, 743 &nsegs, first); 744 first = 0; 745 } 746 } 747 } else { 748 error = EINVAL; 749 } 750 751 if (error) { 752 /* force "no valid mappings" in callback */ 753 (*callback)(callback_arg, dmat->segments, 0, 0, error); 754 } else { 755 (*callback)(callback_arg, dmat->segments, 756 nsegs+1, m0->m_pkthdr.len, error); 757 } 758 CTR3(KTR_BUSDMA, "bus_dmamap_load_mbuf: tag %p tag flags 0x%x " 759 "error %d", dmat, dmat->flags, error); 760 return (error); 761} 762 763/* 764 * Like _bus_dmamap_load(), but for uios. 765 */ 766int 767bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 768 struct uio *uio, 769 bus_dmamap_callback2_t *callback, void *callback_arg, 770 int flags) 771{ 772 bus_addr_t lastaddr; 773 int nsegs, error, first, i; 774 bus_size_t resid; 775 struct iovec *iov; 776 pmap_t pmap; 777 778 flags |= BUS_DMA_NOWAIT; 779 resid = uio->uio_resid; 780 iov = uio->uio_iov; 781 782 if (uio->uio_segflg == UIO_USERSPACE) { 783 KASSERT(uio->uio_td != NULL, 784 ("bus_dmamap_load_uio: USERSPACE but no proc")); 785 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace); 786 } else 787 pmap = NULL; 788 789 nsegs = 0; 790 error = 0; 791 first = 1; 792 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 793 /* 794 * Now at the first iovec to load. Load each iovec 795 * until we have exhausted the residual count. 796 */ 797 bus_size_t minlen = 798 resid < iov[i].iov_len ? resid : iov[i].iov_len; 799 caddr_t addr = (caddr_t) iov[i].iov_base; 800 801 if (minlen > 0) { 802 error = _bus_dmamap_load_buffer(dmat, map, 803 addr, minlen, 804 pmap, flags, &lastaddr, &nsegs, first); 805 first = 0; 806 807 resid -= minlen; 808 } 809 } 810 811 if (error) { 812 /* force "no valid mappings" in callback */ 813 (*callback)(callback_arg, dmat->segments, 0, 0, error); 814 } else { 815 (*callback)(callback_arg, dmat->segments, 816 nsegs+1, uio->uio_resid, error); 817 } 818 CTR3(KTR_BUSDMA, "bus_dmamap_load_uio: tag %p tag flags 0x%x " 819 "error %d", dmat, dmat->flags, error); 820 return (error); 821} 822 823/* 824 * Release the mapping held by map. 825 */ 826void 827_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 828{ 829 struct bounce_page *bpage; 830 831 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 832 STAILQ_REMOVE_HEAD(&map->bpages, links); 833 free_bounce_page(dmat, bpage); 834 } 835} 836 837void 838_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 839{ 840 struct bounce_page *bpage; 841 842 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 843 /* 844 * Handle data bouncing. We might also 845 * want to add support for invalidating 846 * the caches on broken hardware 847 */ 848 total_bounced++; 849 CTR3(KTR_BUSDMA, "_bus_dmamap_sync: tag %p tag flags 0x%x " 850 "op 0x%x performing bounce", op, dmat, dmat->flags); 851 852 if (op & BUS_DMASYNC_PREWRITE) { 853 while (bpage != NULL) { 854 bcopy((void *)bpage->datavaddr, 855 (void *)bpage->vaddr, 856 bpage->datacount); 857 bpage = STAILQ_NEXT(bpage, links); 858 } 859 } 860 861 if (op & BUS_DMASYNC_POSTREAD) { 862 while (bpage != NULL) { 863 bcopy((void *)bpage->vaddr, 864 (void *)bpage->datavaddr, 865 bpage->datacount); 866 bpage = STAILQ_NEXT(bpage, links); 867 } 868 } 869 } 870} 871 872static void 873init_bounce_pages(void *dummy __unused) 874{ 875 876 free_bpages = 0; 877 reserved_bpages = 0; 878 active_bpages = 0; 879 total_bpages = 0; 880 STAILQ_INIT(&bounce_page_list); 881 STAILQ_INIT(&bounce_map_waitinglist); 882 STAILQ_INIT(&bounce_map_callbacklist); 883 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 884} 885SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 886 887static int 888alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 889{ 890 int count; 891 892 count = 0; 893 while (numpages > 0) { 894 struct bounce_page *bpage; 895 896 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 897 M_NOWAIT | M_ZERO); 898 899 if (bpage == NULL) 900 break; 901 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 902 M_NOWAIT, 0ul, 903 dmat->lowaddr, 904 PAGE_SIZE, 905 dmat->boundary); 906 if (bpage->vaddr == 0) { 907 free(bpage, M_DEVBUF); 908 break; 909 } 910 bpage->busaddr = pmap_kextract(bpage->vaddr); 911 mtx_lock(&bounce_lock); 912 STAILQ_INSERT_TAIL(&bounce_page_list, bpage, links); 913 total_bpages++; 914 free_bpages++; 915 mtx_unlock(&bounce_lock); 916 count++; 917 numpages--; 918 } 919 return (count); 920} 921 922static int 923reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 924{ 925 int pages; 926 927 mtx_assert(&bounce_lock, MA_OWNED); 928 pages = MIN(free_bpages, map->pagesneeded - map->pagesreserved); 929 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 930 return (map->pagesneeded - (map->pagesreserved + pages)); 931 free_bpages -= pages; 932 reserved_bpages += pages; 933 map->pagesreserved += pages; 934 pages = map->pagesneeded - map->pagesreserved; 935 936 return (pages); 937} 938 939static bus_addr_t 940add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 941 bus_size_t size) 942{ 943 struct bounce_page *bpage; 944 945 KASSERT(map != NULL && map != &nobounce_dmamap, 946 ("add_bounce_page: bad map %p", map)); 947 948 if (map->pagesneeded == 0) 949 panic("add_bounce_page: map doesn't need any pages"); 950 map->pagesneeded--; 951 952 if (map->pagesreserved == 0) 953 panic("add_bounce_page: map doesn't need any pages"); 954 map->pagesreserved--; 955 956 mtx_lock(&bounce_lock); 957 bpage = STAILQ_FIRST(&bounce_page_list); 958 if (bpage == NULL) 959 panic("add_bounce_page: free page list is empty"); 960 961 STAILQ_REMOVE_HEAD(&bounce_page_list, links); 962 reserved_bpages--; 963 active_bpages++; 964 mtx_unlock(&bounce_lock); 965 966 bpage->datavaddr = vaddr; 967 bpage->datacount = size; 968 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 969 return (bpage->busaddr); 970} 971 972static void 973free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 974{ 975 struct bus_dmamap *map; 976 977 bpage->datavaddr = 0; 978 bpage->datacount = 0; 979 980 mtx_lock(&bounce_lock); 981 STAILQ_INSERT_HEAD(&bounce_page_list, bpage, links); 982 free_bpages++; 983 active_bpages--; 984 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 985 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 986 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 987 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 988 map, links); 989 busdma_swi_pending = 1; 990 total_deferred++; 991 swi_sched(vm_ih, 0); 992 } 993 } 994 mtx_unlock(&bounce_lock); 995} 996 997void 998busdma_swi(void) 999{ 1000 bus_dma_tag_t dmat; 1001 struct bus_dmamap *map; 1002 1003 mtx_lock(&bounce_lock); 1004 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1005 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1006 mtx_unlock(&bounce_lock); 1007 dmat = map->dmat; 1008 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK); 1009 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1010 map->callback, map->callback_arg, /*flags*/0); 1011 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK); 1012 mtx_lock(&bounce_lock); 1013 } 1014 mtx_unlock(&bounce_lock); 1015} 1016