1 /* $NetBSD: isa_dma.c,v 1.6 2007/03/06 14:12:10 tsutsui Exp $ */ 2 3 #define ISA_DMA_STATS 4 5 /*- 6 * Copyright (c) 1996, 1997, 1998 The NetBSD Foundation, Inc. 7 * All rights reserved. 8 * 9 * This code is derived from software contributed to The NetBSD Foundation 10 * by Charles M. Hannum and by Jason R. Thorpe of the Numerical Aerospace 11 * Simulation Facility, NASA Ames Research Center. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. All advertising materials mentioning features or use of this software 22 * must display the following acknowledgement: 23 * This product includes software developed by the NetBSD 24 * Foundation, Inc. and its contributors. 25 * 4. Neither the name of The NetBSD Foundation nor the names of its 26 * contributors may be used to endorse or promote products derived 27 * from this software without specific prior written permission. 28 * 29 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 30 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 31 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 32 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 33 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 34 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 35 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 36 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 37 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 38 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 39 * POSSIBILITY OF SUCH DAMAGE. 40 */ 41 42 #include <sys/cdefs.h> 43 __KERNEL_RCSID(0, "$NetBSD: isa_dma.c,v 1.6 2007/03/06 14:12:10 tsutsui Exp $"); 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/kernel.h> 48 #include <sys/syslog.h> 49 #include <sys/device.h> 50 #include <sys/malloc.h> 51 #include <sys/proc.h> 52 #include <sys/mbuf.h> 53 54 #define _ATARI_BUS_DMA_PRIVATE 55 #include <machine/bus.h> 56 57 #include <dev/isa/isareg.h> 58 #include <dev/isa/isavar.h> 59 60 #include <uvm/uvm_extern.h> 61 62 extern paddr_t avail_end; 63 64 /* 65 * Cookie used by ISA dma. A pointer to one of these it stashed in 66 * the DMA map. 67 */ 68 struct atari_isa_dma_cookie { 69 int id_flags; /* flags; see below */ 70 71 /* 72 * Information about the original buffer used during 73 * DMA map syncs. Note that origibuflen is only used 74 * for ID_BUFTYPE_LINEAR. 75 */ 76 void *id_origbuf; /* pointer to orig buffer if 77 bouncing */ 78 bus_size_t id_origbuflen; /* ...and size */ 79 int id_buftype; /* type of buffer */ 80 81 void *id_bouncebuf; /* pointer to the bounce buffer */ 82 bus_size_t id_bouncebuflen; /* ...and size */ 83 int id_nbouncesegs; /* number of valid bounce segs */ 84 bus_dma_segment_t id_bouncesegs[0]; /* array of bounce buffer 85 physical memory segments */ 86 }; 87 88 /* id_flags */ 89 #define ID_MIGHT_NEED_BOUNCE 0x01 /* map could need bounce buffers */ 90 #define ID_HAS_BOUNCE 0x02 /* map currently has bounce buffers */ 91 #define ID_IS_BOUNCING 0x04 /* map is bouncing current xfer */ 92 93 /* id_buftype */ 94 #define ID_BUFTYPE_INVALID 0 95 #define ID_BUFTYPE_LINEAR 1 96 #define ID_BUFTYPE_MBUF 2 97 #define ID_BUFTYPE_UIO 3 98 #define ID_BUFTYPE_RAW 4 99 100 int _isa_bus_dmamap_create __P((bus_dma_tag_t, bus_size_t, int, 101 bus_size_t, bus_size_t, int, bus_dmamap_t *)); 102 void _isa_bus_dmamap_destroy __P((bus_dma_tag_t, bus_dmamap_t)); 103 int _isa_bus_dmamap_load __P((bus_dma_tag_t, bus_dmamap_t, void *, 104 bus_size_t, struct proc *, int)); 105 int _isa_bus_dmamap_load_mbuf __P((bus_dma_tag_t, bus_dmamap_t, 106 struct mbuf *, int)); 107 int _isa_bus_dmamap_load_uio __P((bus_dma_tag_t, bus_dmamap_t, 108 struct uio *, int)); 109 int _isa_bus_dmamap_load_raw __P((bus_dma_tag_t, bus_dmamap_t, 110 bus_dma_segment_t *, int, bus_size_t, int)); 111 void _isa_bus_dmamap_unload __P((bus_dma_tag_t, bus_dmamap_t)); 112 void _isa_bus_dmamap_sync __P((bus_dma_tag_t, bus_dmamap_t, 113 bus_addr_t, bus_size_t, int)); 114 115 int _isa_bus_dmamem_alloc __P((bus_dma_tag_t, bus_size_t, bus_size_t, 116 bus_size_t, bus_dma_segment_t *, int, int *, int)); 117 118 int _isa_dma_alloc_bouncebuf __P((bus_dma_tag_t, bus_dmamap_t, 119 bus_size_t, int)); 120 void _isa_dma_free_bouncebuf __P((bus_dma_tag_t, bus_dmamap_t)); 121 122 /* 123 * Entry points for ISA DMA. These are mostly wrappers around 124 * the generic functions that understand how to deal with bounce 125 * buffers, if necessary. 126 */ 127 struct atari_bus_dma_tag isa_bus_dma_tag = { 128 ISA_DMA_BOUNCE_THRESHOLD, 129 0, 130 _isa_bus_dmamap_create, 131 _isa_bus_dmamap_destroy, 132 _isa_bus_dmamap_load, 133 _isa_bus_dmamap_load_mbuf, 134 _isa_bus_dmamap_load_uio, 135 _isa_bus_dmamap_load_raw, 136 _isa_bus_dmamap_unload, 137 _isa_bus_dmamap_sync, 138 }; 139 140 /********************************************************************** 141 * bus.h dma interface entry points 142 **********************************************************************/ 143 144 #ifdef ISA_DMA_STATS 145 #define STAT_INCR(v) (v)++ 146 #define STAT_DECR(v) do { \ 147 if ((v) == 0) \ 148 printf("%s:%d -- Already 0!\n", __FILE__, __LINE__); \ 149 else \ 150 (v)--; \ 151 } while (0) 152 u_long isa_dma_stats_loads; 153 u_long isa_dma_stats_bounces; 154 u_long isa_dma_stats_nbouncebufs; 155 #else 156 #define STAT_INCR(v) 157 #define STAT_DECR(v) 158 #endif 159 160 /* 161 * Create an ISA DMA map. 162 */ 163 int 164 _isa_bus_dmamap_create(t, size, nsegments, maxsegsz, boundary, flags, dmamp) 165 bus_dma_tag_t t; 166 bus_size_t size; 167 int nsegments; 168 bus_size_t maxsegsz; 169 bus_size_t boundary; 170 int flags; 171 bus_dmamap_t *dmamp; 172 { 173 struct atari_isa_dma_cookie *cookie; 174 bus_dmamap_t map; 175 int error, cookieflags; 176 void *cookiestore; 177 size_t cookiesize; 178 179 /* Call common function to create the basic map. */ 180 error = _bus_dmamap_create(t, size, nsegments, maxsegsz, boundary, 181 flags, dmamp); 182 if (error) 183 return (error); 184 185 map = *dmamp; 186 map->_dm_cookie = NULL; 187 188 cookiesize = sizeof(struct atari_isa_dma_cookie); 189 190 /* 191 * ISA only has 24-bits of address space. This means 192 * we can't DMA to pages over 16M. In order to DMA to 193 * arbitrary buffers, we use "bounce buffers" - pages 194 * in memory below the 16M boundary. On DMA reads, 195 * DMA happens to the bounce buffers, and is copied into 196 * the caller's buffer. On writes, data is copied into 197 * but bounce buffer, and the DMA happens from those 198 * pages. To software using the DMA mapping interface, 199 * this looks simply like a data cache. 200 * 201 * If we have more than 16M of RAM in the system, we may 202 * need bounce buffers. We check and remember that here. 203 * 204 * There are exceptions, however. VLB devices can do 205 * 32-bit DMA, and indicate that here. 206 * 207 * ...or, there is an opposite case. The most segments 208 * a transfer will require is (maxxfer / PAGE_SIZE) + 1. If 209 * the caller can't handle that many segments (e.g. the 210 * ISA DMA controller), we may have to bounce it as well. 211 */ 212 if (avail_end <= t->_bounce_thresh || 213 (flags & ISABUS_DMA_32BIT) != 0) { 214 /* Bouncing not necessary due to memory size. */ 215 map->_dm_bounce_thresh = 0; 216 } 217 cookieflags = 0; 218 if (map->_dm_bounce_thresh != 0 || 219 ((map->_dm_size / PAGE_SIZE) + 1) > map->_dm_segcnt) { 220 cookieflags |= ID_MIGHT_NEED_BOUNCE; 221 cookiesize += (sizeof(bus_dma_segment_t) * map->_dm_segcnt); 222 } 223 224 /* 225 * Allocate our cookie. 226 */ 227 if ((cookiestore = malloc(cookiesize, M_DMAMAP, 228 (flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK)) == NULL) { 229 error = ENOMEM; 230 goto out; 231 } 232 memset(cookiestore, 0, cookiesize); 233 cookie = (struct atari_isa_dma_cookie *)cookiestore; 234 cookie->id_flags = cookieflags; 235 map->_dm_cookie = cookie; 236 237 if (cookieflags & ID_MIGHT_NEED_BOUNCE) { 238 /* 239 * Allocate the bounce pages now if the caller 240 * wishes us to do so. 241 */ 242 if ((flags & BUS_DMA_ALLOCNOW) == 0) 243 goto out; 244 245 error = _isa_dma_alloc_bouncebuf(t, map, size, flags); 246 } 247 248 out: 249 if (error) { 250 if (map->_dm_cookie != NULL) 251 free(map->_dm_cookie, M_DMAMAP); 252 _bus_dmamap_destroy(t, map); 253 } 254 return (error); 255 } 256 257 /* 258 * Destroy an ISA DMA map. 259 */ 260 void 261 _isa_bus_dmamap_destroy(t, map) 262 bus_dma_tag_t t; 263 bus_dmamap_t map; 264 { 265 struct atari_isa_dma_cookie *cookie = map->_dm_cookie; 266 267 /* 268 * Free any bounce pages this map might hold. 269 */ 270 if (cookie->id_flags & ID_HAS_BOUNCE) 271 _isa_dma_free_bouncebuf(t, map); 272 273 free(cookie, M_DMAMAP); 274 _bus_dmamap_destroy(t, map); 275 } 276 277 /* 278 * Load an ISA DMA map with a linear buffer. 279 */ 280 int 281 _isa_bus_dmamap_load(t, map, buf, buflen, p, flags) 282 bus_dma_tag_t t; 283 bus_dmamap_t map; 284 void *buf; 285 bus_size_t buflen; 286 struct proc *p; 287 int flags; 288 { 289 struct atari_isa_dma_cookie *cookie = map->_dm_cookie; 290 int error; 291 292 STAT_INCR(isa_dma_stats_loads); 293 294 /* 295 * Make sure that on error condition we return "no valid mappings." 296 */ 297 map->dm_mapsize = 0; 298 map->dm_nsegs = 0; 299 300 /* 301 * Try to load the map the normal way. If this errors out, 302 * and we can bounce, we will. 303 */ 304 error = _bus_dmamap_load(t, map, buf, buflen, p, flags); 305 if (error == 0 || 306 (error != 0 && (cookie->id_flags & ID_MIGHT_NEED_BOUNCE) == 0)) 307 return (error); 308 309 /* 310 * First attempt failed; bounce it. 311 */ 312 313 STAT_INCR(isa_dma_stats_bounces); 314 315 /* 316 * Allocate bounce pages, if necessary. 317 */ 318 if ((cookie->id_flags & ID_HAS_BOUNCE) == 0) { 319 error = _isa_dma_alloc_bouncebuf(t, map, buflen, flags); 320 if (error) 321 return (error); 322 } 323 324 /* 325 * Cache a pointer to the caller's buffer and load the DMA map 326 * with the bounce buffer. 327 */ 328 cookie->id_origbuf = buf; 329 cookie->id_origbuflen = buflen; 330 cookie->id_buftype = ID_BUFTYPE_LINEAR; 331 error = _bus_dmamap_load(t, map, cookie->id_bouncebuf, buflen, 332 p, flags); 333 if (error) { 334 /* 335 * Free the bounce pages, unless our resources 336 * are reserved for our exclusive use. 337 */ 338 if ((map->_dm_flags & BUS_DMA_ALLOCNOW) == 0) 339 _isa_dma_free_bouncebuf(t, map); 340 return (error); 341 } 342 343 /* ...so _isa_bus_dmamap_sync() knows we're bouncing */ 344 cookie->id_flags |= ID_IS_BOUNCING; 345 return (0); 346 } 347 348 /* 349 * Like _isa_bus_dmamap_load(), but for mbufs. 350 */ 351 int 352 _isa_bus_dmamap_load_mbuf(t, map, m0, flags) 353 bus_dma_tag_t t; 354 bus_dmamap_t map; 355 struct mbuf *m0; 356 int flags; 357 { 358 struct atari_isa_dma_cookie *cookie = map->_dm_cookie; 359 int error; 360 361 /* 362 * Make sure on error condition we return "no valid mappings." 363 */ 364 map->dm_mapsize = 0; 365 map->dm_nsegs = 0; 366 367 #ifdef DIAGNOSTIC 368 if ((m0->m_flags & M_PKTHDR) == 0) 369 panic("_isa_bus_dmamap_load_mbuf: no packet header"); 370 #endif 371 372 if (m0->m_pkthdr.len > map->_dm_size) 373 return (EINVAL); 374 375 /* 376 * Try to load the map the normal way. If this errors out, 377 * and we can bounce, we will. 378 */ 379 error = _bus_dmamap_load_mbuf(t, map, m0, flags); 380 if (error == 0 || 381 (error != 0 && (cookie->id_flags & ID_MIGHT_NEED_BOUNCE) == 0)) 382 return (error); 383 384 /* 385 * First attempt failed; bounce it. 386 */ 387 388 STAT_INCR(isa_dma_stats_bounces); 389 390 /* 391 * Allocate bounce pages, if necessary. 392 */ 393 if ((cookie->id_flags & ID_HAS_BOUNCE) == 0) { 394 error = _isa_dma_alloc_bouncebuf(t, map, m0->m_pkthdr.len, 395 flags); 396 if (error) 397 return (error); 398 } 399 400 /* 401 * Cache a pointer to the caller's buffer and load the DMA map 402 * with the bounce buffer. 403 */ 404 cookie->id_origbuf = m0; 405 cookie->id_origbuflen = m0->m_pkthdr.len; /* not really used */ 406 cookie->id_buftype = ID_BUFTYPE_MBUF; 407 error = _bus_dmamap_load(t, map, cookie->id_bouncebuf, 408 m0->m_pkthdr.len, NULL, flags); 409 if (error) { 410 /* 411 * Free the bounce pages, unless our resources 412 * are reserved for our exclusive use. 413 */ 414 if ((map->_dm_flags & BUS_DMA_ALLOCNOW) == 0) 415 _isa_dma_free_bouncebuf(t, map); 416 return (error); 417 } 418 419 /* ...so _isa_bus_dmamap_sync() knows we're bouncing */ 420 cookie->id_flags |= ID_IS_BOUNCING; 421 return (0); 422 } 423 424 /* 425 * Like _isa_bus_dmamap_load(), but for uios. 426 */ 427 int 428 _isa_bus_dmamap_load_uio(t, map, uio, flags) 429 bus_dma_tag_t t; 430 bus_dmamap_t map; 431 struct uio *uio; 432 int flags; 433 { 434 435 panic("_isa_bus_dmamap_load_uio: not implemented"); 436 } 437 438 /* 439 * Like _isa_bus_dmamap_load(), but for raw memory allocated with 440 * bus_dmamem_alloc(). 441 */ 442 int 443 _isa_bus_dmamap_load_raw(t, map, segs, nsegs, size, flags) 444 bus_dma_tag_t t; 445 bus_dmamap_t map; 446 bus_dma_segment_t *segs; 447 int nsegs; 448 bus_size_t size; 449 int flags; 450 { 451 452 panic("_isa_bus_dmamap_load_raw: not implemented"); 453 } 454 455 /* 456 * Unload an ISA DMA map. 457 */ 458 void 459 _isa_bus_dmamap_unload(t, map) 460 bus_dma_tag_t t; 461 bus_dmamap_t map; 462 { 463 struct atari_isa_dma_cookie *cookie = map->_dm_cookie; 464 465 /* 466 * If we have bounce pages, free them, unless they're 467 * reserved for our exclusive use. 468 */ 469 if ((cookie->id_flags & ID_HAS_BOUNCE) && 470 (map->_dm_flags & BUS_DMA_ALLOCNOW) == 0) 471 _isa_dma_free_bouncebuf(t, map); 472 473 cookie->id_flags &= ~ID_IS_BOUNCING; 474 cookie->id_buftype = ID_BUFTYPE_INVALID; 475 476 /* 477 * Do the generic bits of the unload. 478 */ 479 _bus_dmamap_unload(t, map); 480 } 481 482 /* 483 * Synchronize an ISA DMA map. 484 */ 485 void 486 _isa_bus_dmamap_sync(t, map, offset, len, ops) 487 bus_dma_tag_t t; 488 bus_dmamap_t map; 489 bus_addr_t offset; 490 bus_size_t len; 491 int ops; 492 { 493 struct atari_isa_dma_cookie *cookie = map->_dm_cookie; 494 495 /* 496 * Mixing PRE and POST operations is not allowed. 497 */ 498 if ((ops & (BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE)) != 0 && 499 (ops & (BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE)) != 0) 500 panic("_isa_bus_dmamap_sync: mix PRE and POST"); 501 502 #ifdef DIAGNOSTIC 503 if ((ops & (BUS_DMASYNC_PREWRITE|BUS_DMASYNC_POSTREAD)) != 0) { 504 if (offset >= map->dm_mapsize) 505 panic("_isa_bus_dmamap_sync: bad offset"); 506 if (len == 0 || (offset + len) > map->dm_mapsize) 507 panic("_isa_bus_dmamap_sync: bad length"); 508 } 509 #endif 510 511 /* 512 * If we're not bouncing, just return; nothing to do. 513 */ 514 if ((cookie->id_flags & ID_IS_BOUNCING) == 0) 515 return; 516 517 switch (cookie->id_buftype) { 518 case ID_BUFTYPE_LINEAR: 519 /* 520 * Nothing to do for pre-read. 521 */ 522 523 if (ops & BUS_DMASYNC_PREWRITE) { 524 /* 525 * Copy the caller's buffer to the bounce buffer. 526 */ 527 memcpy((char *)cookie->id_bouncebuf + offset, 528 (char *)cookie->id_origbuf + offset, len); 529 } 530 531 if (ops & BUS_DMASYNC_POSTREAD) { 532 /* 533 * Copy the bounce buffer to the caller's buffer. 534 */ 535 memcpy((char *)cookie->id_origbuf + offset, 536 (char *)cookie->id_bouncebuf + offset, len); 537 } 538 539 /* 540 * Nothing to do for post-write. 541 */ 542 break; 543 544 case ID_BUFTYPE_MBUF: 545 { 546 struct mbuf *m, *m0 = cookie->id_origbuf; 547 bus_size_t minlen, moff; 548 549 /* 550 * Nothing to do for pre-read. 551 */ 552 553 if (ops & BUS_DMASYNC_PREWRITE) { 554 /* 555 * Copy the caller's buffer to the bounce buffer. 556 */ 557 m_copydata(m0, offset, len, 558 (char *)cookie->id_bouncebuf + offset); 559 } 560 561 if (ops & BUS_DMASYNC_POSTREAD) { 562 /* 563 * Copy the bounce buffer to the caller's buffer. 564 */ 565 for (moff = offset, m = m0; m != NULL && len != 0; 566 m = m->m_next) { 567 /* Find the beginning mbuf. */ 568 if (moff >= m->m_len) { 569 moff -= m->m_len; 570 continue; 571 } 572 573 /* 574 * Now at the first mbuf to sync; nail 575 * each one until we have exhausted the 576 * length. 577 */ 578 minlen = len < m->m_len - moff ? 579 len : m->m_len - moff; 580 581 memcpy(mtod(m, char *) + moff, 582 (char *)cookie->id_bouncebuf + offset, 583 minlen); 584 585 moff = 0; 586 len -= minlen; 587 offset += minlen; 588 } 589 } 590 591 /* 592 * Nothing to do for post-write. 593 */ 594 break; 595 } 596 597 case ID_BUFTYPE_UIO: 598 panic("_isa_bus_dmamap_sync: ID_BUFTYPE_UIO"); 599 break; 600 601 case ID_BUFTYPE_RAW: 602 panic("_isa_bus_dmamap_sync: ID_BUFTYPE_RAW"); 603 break; 604 605 case ID_BUFTYPE_INVALID: 606 panic("_isa_bus_dmamap_sync: ID_BUFTYPE_INVALID"); 607 break; 608 609 default: 610 printf("unknown buffer type %d\n", cookie->id_buftype); 611 panic("_isa_bus_dmamap_sync"); 612 } 613 } 614 615 /* 616 * Allocate memory safe for ISA DMA. 617 */ 618 int 619 _isa_bus_dmamem_alloc(t, size, alignment, boundary, segs, nsegs, rsegs, flags) 620 bus_dma_tag_t t; 621 bus_size_t size, alignment, boundary; 622 bus_dma_segment_t *segs; 623 int nsegs; 624 int *rsegs; 625 int flags; 626 { 627 paddr_t high; 628 629 if (avail_end > ISA_DMA_BOUNCE_THRESHOLD) 630 high = trunc_page(ISA_DMA_BOUNCE_THRESHOLD); 631 else 632 high = trunc_page(avail_end); 633 634 return (bus_dmamem_alloc_range(t, size, alignment, boundary, 635 segs, nsegs, rsegs, flags, 0, high)); 636 } 637 638 /********************************************************************** 639 * ISA DMA utility functions 640 **********************************************************************/ 641 642 int 643 _isa_dma_alloc_bouncebuf(t, map, size, flags) 644 bus_dma_tag_t t; 645 bus_dmamap_t map; 646 bus_size_t size; 647 int flags; 648 { 649 struct atari_isa_dma_cookie *cookie = map->_dm_cookie; 650 int error = 0; 651 652 cookie->id_bouncebuflen = round_page(size); 653 error = _isa_bus_dmamem_alloc(t, cookie->id_bouncebuflen, 654 PAGE_SIZE, map->_dm_boundary, cookie->id_bouncesegs, 655 map->_dm_segcnt, &cookie->id_nbouncesegs, flags); 656 if (error) 657 goto out; 658 error = bus_dmamem_map(t, cookie->id_bouncesegs, 659 cookie->id_nbouncesegs, cookie->id_bouncebuflen, 660 (void **)&cookie->id_bouncebuf, flags); 661 662 out: 663 if (error) { 664 bus_dmamem_free(t, cookie->id_bouncesegs, 665 cookie->id_nbouncesegs); 666 cookie->id_bouncebuflen = 0; 667 cookie->id_nbouncesegs = 0; 668 } else { 669 cookie->id_flags |= ID_HAS_BOUNCE; 670 STAT_INCR(isa_dma_stats_nbouncebufs); 671 } 672 673 return (error); 674 } 675 676 void 677 _isa_dma_free_bouncebuf(t, map) 678 bus_dma_tag_t t; 679 bus_dmamap_t map; 680 { 681 struct atari_isa_dma_cookie *cookie = map->_dm_cookie; 682 683 STAT_DECR(isa_dma_stats_nbouncebufs); 684 685 bus_dmamem_unmap(t, cookie->id_bouncebuf, 686 cookie->id_bouncebuflen); 687 bus_dmamem_free(t, cookie->id_bouncesegs, 688 cookie->id_nbouncesegs); 689 cookie->id_bouncebuflen = 0; 690 cookie->id_nbouncesegs = 0; 691 cookie->id_flags &= ~ID_HAS_BOUNCE; 692 } 693