1 /* $NetBSD: bus_dma.c,v 1.49 2002/04/26 04:15:18 thorpej Exp $ */ 2 3 /*- 4 * Copyright (c) 1997, 1998 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the NetBSD 22 * Foundation, Inc. and its contributors. 23 * 4. Neither the name of The NetBSD Foundation nor the names of its 24 * contributors may be used to endorse or promote products derived 25 * from this software without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 37 * POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40 #include <sys/cdefs.h> /* RCS ID & Copyright macro defns */ 41 42 __KERNEL_RCSID(0, "$NetBSD: bus_dma.c,v 1.49 2002/04/26 04:15:18 thorpej Exp $"); 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/kernel.h> 47 #include <sys/device.h> 48 #include <sys/malloc.h> 49 #include <sys/proc.h> 50 #include <sys/mbuf.h> 51 52 #include <uvm/uvm_extern.h> 53 54 #define _ALPHA_BUS_DMA_PRIVATE 55 #include <machine/bus.h> 56 #include <machine/intr.h> 57 58 int _bus_dmamap_load_buffer_direct(bus_dma_tag_t, 59 bus_dmamap_t, void *, bus_size_t, struct proc *, int, 60 paddr_t *, int *, int); 61 62 extern paddr_t avail_start, avail_end; /* from pmap.c */ 63 64 /* 65 * Common function for DMA map creation. May be called by bus-specific 66 * DMA map creation functions. 67 */ 68 int 69 _bus_dmamap_create(bus_dma_tag_t t, bus_size_t size, int nsegments, 70 bus_size_t maxsegsz, bus_size_t boundary, int flags, bus_dmamap_t *dmamp) 71 { 72 struct alpha_bus_dmamap *map; 73 void *mapstore; 74 size_t mapsize; 75 76 /* 77 * Allocate and initialize the DMA map. The end of the map 78 * is a variable-sized array of segments, so we allocate enough 79 * room for them in one shot. 80 * 81 * Note we don't preserve the WAITOK or NOWAIT flags. Preservation 82 * of ALLOCNOW notifes others that we've reserved these resources, 83 * and they are not to be freed. 84 * 85 * The bus_dmamap_t includes one bus_dma_segment_t, hence 86 * the (nsegments - 1). 87 */ 88 mapsize = sizeof(struct alpha_bus_dmamap) + 89 (sizeof(bus_dma_segment_t) * (nsegments - 1)); 90 if ((mapstore = malloc(mapsize, M_DMAMAP, 91 (flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK)) == NULL) 92 return (ENOMEM); 93 94 memset(mapstore, 0, mapsize); 95 map = (struct alpha_bus_dmamap *)mapstore; 96 map->_dm_size = size; 97 map->_dm_segcnt = nsegments; 98 map->_dm_maxsegsz = maxsegsz; 99 if (t->_boundary != 0 && t->_boundary < boundary) 100 map->_dm_boundary = t->_boundary; 101 else 102 map->_dm_boundary = boundary; 103 map->_dm_flags = flags & ~(BUS_DMA_WAITOK|BUS_DMA_NOWAIT); 104 map->dm_mapsize = 0; /* no valid mappings */ 105 map->dm_nsegs = 0; 106 map->_dm_window = NULL; 107 108 *dmamp = map; 109 return (0); 110 } 111 112 /* 113 * Common function for DMA map destruction. May be called by bus-specific 114 * DMA map destruction functions. 115 */ 116 void 117 _bus_dmamap_destroy(bus_dma_tag_t t, bus_dmamap_t map) 118 { 119 120 free(map, M_DMAMAP); 121 } 122 123 /* 124 * Utility function to load a linear buffer. lastaddrp holds state 125 * between invocations (for multiple-buffer loads). segp contains 126 * the starting segment on entrance, and the ending segment on exit. 127 * first indicates if this is the first invocation of this function. 128 */ 129 int 130 _bus_dmamap_load_buffer_direct(bus_dma_tag_t t, bus_dmamap_t map, 131 void *buf, size_t buflen, struct proc *p, int flags, paddr_t *lastaddrp, 132 int *segp, int first) 133 { 134 bus_size_t sgsize; 135 bus_addr_t curaddr, lastaddr, baddr, bmask; 136 vaddr_t vaddr = (vaddr_t)buf; 137 int seg; 138 139 lastaddr = *lastaddrp; 140 bmask = ~(map->_dm_boundary - 1); 141 142 for (seg = *segp; buflen > 0 ; ) { 143 /* 144 * Get the physical address for this segment. 145 */ 146 if (p != NULL) 147 (void) pmap_extract(p->p_vmspace->vm_map.pmap, 148 vaddr, &curaddr); 149 else 150 curaddr = vtophys(vaddr); 151 152 /* 153 * If we're beyond the current DMA window, indicate 154 * that and try to fall back into SGMAPs. 155 */ 156 if (t->_wsize != 0 && curaddr >= t->_wsize) 157 return (EINVAL); 158 159 curaddr |= t->_wbase; 160 161 /* 162 * Compute the segment size, and adjust counts. 163 */ 164 sgsize = NBPG - ((u_long)vaddr & PGOFSET); 165 if (buflen < sgsize) 166 sgsize = buflen; 167 if (map->_dm_maxsegsz < sgsize) 168 sgsize = map->_dm_maxsegsz; 169 170 /* 171 * Make sure we don't cross any boundaries. 172 */ 173 if (map->_dm_boundary > 0) { 174 baddr = (curaddr + map->_dm_boundary) & bmask; 175 if (sgsize > (baddr - curaddr)) 176 sgsize = (baddr - curaddr); 177 } 178 179 /* 180 * Insert chunk into a segment, coalescing with 181 * the previous segment if possible. 182 */ 183 if (first) { 184 map->dm_segs[seg].ds_addr = curaddr; 185 map->dm_segs[seg].ds_len = sgsize; 186 first = 0; 187 } else { 188 if ((map->_dm_flags & DMAMAP_NO_COALESCE) == 0 && 189 curaddr == lastaddr && 190 (map->dm_segs[seg].ds_len + sgsize) <= 191 map->_dm_maxsegsz && 192 (map->_dm_boundary == 0 || 193 (map->dm_segs[seg].ds_addr & bmask) == 194 (curaddr & bmask))) 195 map->dm_segs[seg].ds_len += sgsize; 196 else { 197 if (++seg >= map->_dm_segcnt) 198 break; 199 map->dm_segs[seg].ds_addr = curaddr; 200 map->dm_segs[seg].ds_len = sgsize; 201 } 202 } 203 204 lastaddr = curaddr + sgsize; 205 vaddr += sgsize; 206 buflen -= sgsize; 207 } 208 209 *segp = seg; 210 *lastaddrp = lastaddr; 211 212 /* 213 * Did we fit? 214 */ 215 if (buflen != 0) { 216 /* 217 * If there is a chained window, we will automatically 218 * fall back to it. 219 */ 220 return (EFBIG); /* XXX better return value here? */ 221 } 222 223 return (0); 224 } 225 226 /* 227 * Common function for loading a direct-mapped DMA map with a linear 228 * buffer. Called by bus-specific DMA map load functions with the 229 * OR value appropriate for indicating "direct-mapped" for that 230 * chipset. 231 */ 232 int 233 _bus_dmamap_load_direct(bus_dma_tag_t t, bus_dmamap_t map, void *buf, 234 bus_size_t buflen, struct proc *p, int flags) 235 { 236 paddr_t lastaddr; 237 int seg, error; 238 239 /* 240 * Make sure that on error condition we return "no valid mappings". 241 */ 242 map->dm_mapsize = 0; 243 map->dm_nsegs = 0; 244 245 if (buflen > map->_dm_size) 246 return (EINVAL); 247 248 seg = 0; 249 error = _bus_dmamap_load_buffer_direct(t, map, buf, buflen, 250 p, flags, &lastaddr, &seg, 1); 251 if (error == 0) { 252 map->dm_mapsize = buflen; 253 map->dm_nsegs = seg + 1; 254 map->_dm_window = t; 255 } else if (t->_next_window != NULL) { 256 /* 257 * Give the next window a chance. 258 */ 259 error = bus_dmamap_load(t->_next_window, map, buf, buflen, 260 p, flags); 261 } 262 return (error); 263 } 264 265 /* 266 * Like _bus_dmamap_load_direct(), but for mbufs. 267 */ 268 int 269 _bus_dmamap_load_mbuf_direct(bus_dma_tag_t t, bus_dmamap_t map, 270 struct mbuf *m0, int flags) 271 { 272 paddr_t lastaddr; 273 int seg, error, first; 274 struct mbuf *m; 275 276 /* 277 * Make sure that on error condition we return "no valid mappings." 278 */ 279 map->dm_mapsize = 0; 280 map->dm_nsegs = 0; 281 282 #ifdef DIAGNOSTIC 283 if ((m0->m_flags & M_PKTHDR) == 0) 284 panic("_bus_dmamap_load_mbuf_direct: no packet header"); 285 #endif 286 287 if (m0->m_pkthdr.len > map->_dm_size) 288 return (EINVAL); 289 290 first = 1; 291 seg = 0; 292 error = 0; 293 for (m = m0; m != NULL && error == 0; m = m->m_next) { 294 error = _bus_dmamap_load_buffer_direct(t, map, 295 m->m_data, m->m_len, NULL, flags, &lastaddr, &seg, first); 296 first = 0; 297 } 298 if (error == 0) { 299 map->dm_mapsize = m0->m_pkthdr.len; 300 map->dm_nsegs = seg + 1; 301 map->_dm_window = t; 302 } else if (t->_next_window != NULL) { 303 /* 304 * Give the next window a chance. 305 */ 306 error = bus_dmamap_load_mbuf(t->_next_window, map, m0, flags); 307 } 308 return (error); 309 } 310 311 /* 312 * Like _bus_dmamap_load_direct(), but for uios. 313 */ 314 int 315 _bus_dmamap_load_uio_direct(bus_dma_tag_t t, bus_dmamap_t map, 316 struct uio *uio, int flags) 317 { 318 paddr_t lastaddr; 319 int seg, i, error, first; 320 bus_size_t minlen, resid; 321 struct proc *p = NULL; 322 struct iovec *iov; 323 caddr_t addr; 324 325 /* 326 * Make sure that on error condition we return "no valid mappings." 327 */ 328 map->dm_mapsize = 0; 329 map->dm_nsegs = 0; 330 331 resid = uio->uio_resid; 332 iov = uio->uio_iov; 333 334 if (uio->uio_segflg == UIO_USERSPACE) { 335 p = uio->uio_procp; 336 #ifdef DIAGNOSTIC 337 if (p == NULL) 338 panic("_bus_dmamap_load_uio_direct: " 339 "USERSPACE but no proc"); 340 #endif 341 } 342 343 first = 1; 344 seg = 0; 345 error = 0; 346 for (i = 0; i < uio->uio_iovcnt && resid != 0 && error == 0; i++) { 347 /* 348 * Now at the first iovec to load. Load each iovec 349 * until we have exhausted the residual count. 350 */ 351 minlen = resid < iov[i].iov_len ? resid : iov[i].iov_len; 352 addr = (caddr_t)iov[i].iov_base; 353 354 error = _bus_dmamap_load_buffer_direct(t, map, 355 addr, minlen, p, flags, &lastaddr, &seg, first); 356 first = 0; 357 358 resid -= minlen; 359 } 360 if (error == 0) { 361 map->dm_mapsize = uio->uio_resid; 362 map->dm_nsegs = seg + 1; 363 map->_dm_window = t; 364 } else if (t->_next_window != NULL) { 365 /* 366 * Give the next window a chance. 367 */ 368 error = bus_dmamap_load_uio(t->_next_window, map, uio, flags); 369 } 370 return (error); 371 } 372 373 /* 374 * Like _bus_dmamap_load_direct(), but for raw memory. 375 */ 376 int 377 _bus_dmamap_load_raw_direct(bus_dma_tag_t t, bus_dmamap_t map, 378 bus_dma_segment_t *segs, int nsegs, bus_size_t size, int flags) 379 { 380 381 panic("_bus_dmamap_load_raw_direct: not implemented"); 382 } 383 384 /* 385 * Common function for unloading a DMA map. May be called by 386 * chipset-specific DMA map unload functions. 387 */ 388 void 389 _bus_dmamap_unload(bus_dma_tag_t t, bus_dmamap_t map) 390 { 391 392 /* 393 * No resources to free; just mark the mappings as 394 * invalid. 395 */ 396 map->dm_mapsize = 0; 397 map->dm_nsegs = 0; 398 map->_dm_window = NULL; 399 } 400 401 /* 402 * Common function for DMA map synchronization. May be called 403 * by chipset-specific DMA map synchronization functions. 404 */ 405 void 406 _bus_dmamap_sync(bus_dma_tag_t t, bus_dmamap_t map, bus_addr_t offset, 407 bus_size_t len, int ops) 408 { 409 410 /* 411 * Flush the store buffer. 412 */ 413 alpha_mb(); 414 } 415 416 /* 417 * Common function for DMA-safe memory allocation. May be called 418 * by bus-specific DMA memory allocation functions. 419 */ 420 int 421 _bus_dmamem_alloc(bus_dma_tag_t t, bus_size_t size, bus_size_t alignment, 422 bus_size_t boundary, bus_dma_segment_t *segs, int nsegs, int *rsegs, 423 int flags) 424 { 425 426 return (_bus_dmamem_alloc_range(t, size, alignment, boundary, 427 segs, nsegs, rsegs, flags, 0, trunc_page(avail_end))); 428 } 429 430 /* 431 * Allocate physical memory from the given physical address range. 432 * Called by DMA-safe memory allocation methods. 433 */ 434 int 435 _bus_dmamem_alloc_range(bus_dma_tag_t t, bus_size_t size, bus_size_t alignment, 436 bus_size_t boundary, bus_dma_segment_t *segs, int nsegs, int *rsegs, 437 int flags, paddr_t low, paddr_t high) 438 { 439 paddr_t curaddr, lastaddr; 440 struct vm_page *m; 441 struct pglist mlist; 442 int curseg, error; 443 444 /* Always round the size. */ 445 size = round_page(size); 446 447 high = avail_end - PAGE_SIZE; 448 449 /* 450 * Allocate pages from the VM system. 451 */ 452 TAILQ_INIT(&mlist); 453 error = uvm_pglistalloc(size, low, high, alignment, boundary, 454 &mlist, nsegs, (flags & BUS_DMA_NOWAIT) == 0); 455 if (error) 456 return (error); 457 458 /* 459 * Compute the location, size, and number of segments actually 460 * returned by the VM code. 461 */ 462 m = mlist.tqh_first; 463 curseg = 0; 464 lastaddr = segs[curseg].ds_addr = VM_PAGE_TO_PHYS(m); 465 segs[curseg].ds_len = PAGE_SIZE; 466 m = m->pageq.tqe_next; 467 468 for (; m != NULL; m = m->pageq.tqe_next) { 469 curaddr = VM_PAGE_TO_PHYS(m); 470 #ifdef DIAGNOSTIC 471 if (curaddr < avail_start || curaddr >= high) { 472 printf("uvm_pglistalloc returned non-sensical" 473 " address 0x%lx\n", curaddr); 474 panic("_bus_dmamem_alloc"); 475 } 476 #endif 477 if (curaddr == (lastaddr + PAGE_SIZE)) 478 segs[curseg].ds_len += PAGE_SIZE; 479 else { 480 curseg++; 481 segs[curseg].ds_addr = curaddr; 482 segs[curseg].ds_len = PAGE_SIZE; 483 } 484 lastaddr = curaddr; 485 } 486 487 *rsegs = curseg + 1; 488 489 return (0); 490 } 491 492 /* 493 * Common function for freeing DMA-safe memory. May be called by 494 * bus-specific DMA memory free functions. 495 */ 496 void 497 _bus_dmamem_free(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs) 498 { 499 struct vm_page *m; 500 bus_addr_t addr; 501 struct pglist mlist; 502 int curseg; 503 504 /* 505 * Build a list of pages to free back to the VM system. 506 */ 507 TAILQ_INIT(&mlist); 508 for (curseg = 0; curseg < nsegs; curseg++) { 509 for (addr = segs[curseg].ds_addr; 510 addr < (segs[curseg].ds_addr + segs[curseg].ds_len); 511 addr += PAGE_SIZE) { 512 m = PHYS_TO_VM_PAGE(addr); 513 TAILQ_INSERT_TAIL(&mlist, m, pageq); 514 } 515 } 516 517 uvm_pglistfree(&mlist); 518 } 519 520 /* 521 * Common function for mapping DMA-safe memory. May be called by 522 * bus-specific DMA memory map functions. 523 */ 524 int 525 _bus_dmamem_map(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs, 526 size_t size, caddr_t *kvap, int flags) 527 { 528 vaddr_t va; 529 bus_addr_t addr; 530 int curseg; 531 532 /* 533 * If we're only mapping 1 segment, use K0SEG, to avoid 534 * TLB thrashing. 535 */ 536 if (nsegs == 1) { 537 *kvap = (caddr_t)ALPHA_PHYS_TO_K0SEG(segs[0].ds_addr); 538 return (0); 539 } 540 541 size = round_page(size); 542 543 va = uvm_km_valloc(kernel_map, size); 544 545 if (va == 0) 546 return (ENOMEM); 547 548 *kvap = (caddr_t)va; 549 550 for (curseg = 0; curseg < nsegs; curseg++) { 551 for (addr = segs[curseg].ds_addr; 552 addr < (segs[curseg].ds_addr + segs[curseg].ds_len); 553 addr += NBPG, va += NBPG, size -= NBPG) { 554 if (size == 0) 555 panic("_bus_dmamem_map: size botch"); 556 pmap_enter(pmap_kernel(), va, addr, 557 VM_PROT_READ | VM_PROT_WRITE, 558 PMAP_WIRED | VM_PROT_READ | VM_PROT_WRITE); 559 } 560 } 561 pmap_update(pmap_kernel()); 562 563 return (0); 564 } 565 566 /* 567 * Common function for unmapping DMA-safe memory. May be called by 568 * bus-specific DMA memory unmapping functions. 569 */ 570 void 571 _bus_dmamem_unmap(bus_dma_tag_t t, caddr_t kva, size_t size) 572 { 573 574 #ifdef DIAGNOSTIC 575 if ((u_long)kva & PGOFSET) 576 panic("_bus_dmamem_unmap"); 577 #endif 578 579 /* 580 * Nothing to do if we mapped it with K0SEG. 581 */ 582 if (kva >= (caddr_t)ALPHA_K0SEG_BASE && 583 kva <= (caddr_t)ALPHA_K0SEG_END) 584 return; 585 586 size = round_page(size); 587 uvm_km_free(kernel_map, (vaddr_t)kva, size); 588 } 589 590 /* 591 * Common functin for mmap(2)'ing DMA-safe memory. May be called by 592 * bus-specific DMA mmap(2)'ing functions. 593 */ 594 paddr_t 595 _bus_dmamem_mmap(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs, 596 off_t off, int prot, int flags) 597 { 598 int i; 599 600 for (i = 0; i < nsegs; i++) { 601 #ifdef DIAGNOSTIC 602 if (off & PGOFSET) 603 panic("_bus_dmamem_mmap: offset unaligned"); 604 if (segs[i].ds_addr & PGOFSET) 605 panic("_bus_dmamem_mmap: segment unaligned"); 606 if (segs[i].ds_len & PGOFSET) 607 panic("_bus_dmamem_mmap: segment size not multiple" 608 " of page size"); 609 #endif 610 if (off >= segs[i].ds_len) { 611 off -= segs[i].ds_len; 612 continue; 613 } 614 615 return (alpha_btop((caddr_t)segs[i].ds_addr + off)); 616 } 617 618 /* Page not found. */ 619 return (-1); 620 } 621