bus_dma.c revision 1.57
1/* $NetBSD: bus_dma.c,v 1.57 2005/03/09 19:04:43 matt 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 1.57 2005/03/09 19:04:43 matt 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 58int _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 62extern 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 */ 68int 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 notifies 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_maxmaxsegsz = 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_maxsegsz = maxsegsz; 105 map->dm_mapsize = 0; /* no valid mappings */ 106 map->dm_nsegs = 0; 107 map->_dm_window = NULL; 108 109 *dmamp = map; 110 return (0); 111} 112 113/* 114 * Common function for DMA map destruction. May be called by bus-specific 115 * DMA map destruction functions. 116 */ 117void 118_bus_dmamap_destroy(bus_dma_tag_t t, bus_dmamap_t map) 119{ 120 121 free(map, M_DMAMAP); 122} 123 124/* 125 * Utility function to load a linear buffer. lastaddrp holds state 126 * between invocations (for multiple-buffer loads). segp contains 127 * the starting segment on entrance, and the ending segment on exit. 128 * first indicates if this is the first invocation of this function. 129 */ 130int 131_bus_dmamap_load_buffer_direct(bus_dma_tag_t t, bus_dmamap_t map, 132 void *buf, size_t buflen, struct proc *p, int flags, paddr_t *lastaddrp, 133 int *segp, int first) 134{ 135 bus_size_t sgsize; 136 bus_addr_t curaddr, lastaddr, baddr, bmask; 137 vaddr_t vaddr = (vaddr_t)buf; 138 int seg; 139 140 lastaddr = *lastaddrp; 141 bmask = ~(map->_dm_boundary - 1); 142 143 for (seg = *segp; buflen > 0 ; ) { 144 /* 145 * Get the physical address for this segment. 146 */ 147 if (p != NULL) 148 (void) pmap_extract(p->p_vmspace->vm_map.pmap, 149 vaddr, &curaddr); 150 else 151 curaddr = vtophys(vaddr); 152 153 /* 154 * If we're beyond the current DMA window, indicate 155 * that and try to fall back into SGMAPs. 156 */ 157 if (t->_wsize != 0 && curaddr >= t->_wsize) 158 return (EINVAL); 159 160 curaddr |= t->_wbase; 161 162 /* 163 * Compute the segment size, and adjust counts. 164 */ 165 sgsize = PAGE_SIZE - ((u_long)vaddr & PGOFSET); 166 if (buflen < sgsize) 167 sgsize = buflen; 168 if (map->dm_maxsegsz < sgsize) 169 sgsize = map->dm_maxsegsz; 170 171 /* 172 * Make sure we don't cross any boundaries. 173 */ 174 if (map->_dm_boundary > 0) { 175 baddr = (curaddr + map->_dm_boundary) & bmask; 176 if (sgsize > (baddr - curaddr)) 177 sgsize = (baddr - curaddr); 178 } 179 180 /* 181 * Insert chunk into a segment, coalescing with 182 * the previous segment if possible. 183 */ 184 if (first) { 185 map->dm_segs[seg].ds_addr = curaddr; 186 map->dm_segs[seg].ds_len = sgsize; 187 first = 0; 188 } else { 189 if ((map->_dm_flags & DMAMAP_NO_COALESCE) == 0 && 190 curaddr == lastaddr && 191 (map->dm_segs[seg].ds_len + sgsize) <= 192 map->dm_maxsegsz && 193 (map->_dm_boundary == 0 || 194 (map->dm_segs[seg].ds_addr & bmask) == 195 (curaddr & bmask))) 196 map->dm_segs[seg].ds_len += sgsize; 197 else { 198 if (++seg >= map->_dm_segcnt) 199 break; 200 map->dm_segs[seg].ds_addr = curaddr; 201 map->dm_segs[seg].ds_len = sgsize; 202 } 203 } 204 205 lastaddr = curaddr + sgsize; 206 vaddr += sgsize; 207 buflen -= sgsize; 208 } 209 210 *segp = seg; 211 *lastaddrp = lastaddr; 212 213 /* 214 * Did we fit? 215 */ 216 if (buflen != 0) { 217 /* 218 * If there is a chained window, we will automatically 219 * fall back to it. 220 */ 221 return (EFBIG); /* XXX better return value here? */ 222 } 223 224 return (0); 225} 226 227/* 228 * Common function for loading a direct-mapped DMA map with a linear 229 * buffer. Called by bus-specific DMA map load functions with the 230 * OR value appropriate for indicating "direct-mapped" for that 231 * chipset. 232 */ 233int 234_bus_dmamap_load_direct(bus_dma_tag_t t, bus_dmamap_t map, void *buf, 235 bus_size_t buflen, struct proc *p, int flags) 236{ 237 paddr_t lastaddr; 238 int seg, error; 239 240 /* 241 * Make sure that on error condition we return "no valid mappings". 242 */ 243 map->dm_mapsize = 0; 244 map->dm_nsegs = 0; 245 KASSERT(map->dm_maxsegsz <= map->_dm_maxmaxsegsz); 246 247 if (buflen > map->_dm_size) 248 return (EINVAL); 249 250 seg = 0; 251 error = _bus_dmamap_load_buffer_direct(t, map, buf, buflen, 252 p, flags, &lastaddr, &seg, 1); 253 if (error == 0) { 254 map->dm_mapsize = buflen; 255 map->dm_nsegs = seg + 1; 256 map->_dm_window = t; 257 } else if (t->_next_window != NULL) { 258 /* 259 * Give the next window a chance. 260 */ 261 error = bus_dmamap_load(t->_next_window, map, buf, buflen, 262 p, flags); 263 } 264 return (error); 265} 266 267/* 268 * Like _bus_dmamap_load_direct(), but for mbufs. 269 */ 270int 271_bus_dmamap_load_mbuf_direct(bus_dma_tag_t t, bus_dmamap_t map, 272 struct mbuf *m0, int flags) 273{ 274 paddr_t lastaddr; 275 int seg, error, first; 276 struct mbuf *m; 277 278 /* 279 * Make sure that on error condition we return "no valid mappings." 280 */ 281 map->dm_mapsize = 0; 282 map->dm_nsegs = 0; 283 KASSERT(map->dm_maxsegsz <= map->_dm_maxmaxsegsz); 284 285#ifdef DIAGNOSTIC 286 if ((m0->m_flags & M_PKTHDR) == 0) 287 panic("_bus_dmamap_load_mbuf_direct: no packet header"); 288#endif 289 290 if (m0->m_pkthdr.len > map->_dm_size) 291 return (EINVAL); 292 293 first = 1; 294 seg = 0; 295 error = 0; 296 for (m = m0; m != NULL && error == 0; m = m->m_next) { 297 if (m->m_len == 0) 298 continue; 299 /* XXX Could be better about coalescing. */ 300 /* XXX Doesn't check boundaries. */ 301 switch (m->m_flags & (M_EXT|M_EXT_CLUSTER)) { 302 case M_EXT|M_EXT_CLUSTER: 303 /* XXX KDASSERT */ 304 KASSERT(m->m_ext.ext_paddr != M_PADDR_INVALID); 305 lastaddr = m->m_ext.ext_paddr + 306 (m->m_data - m->m_ext.ext_buf); 307 have_addr: 308 if (first == 0 && 309 ++seg >= map->_dm_segcnt) { 310 error = EFBIG; 311 break; 312 } 313 314 /* 315 * If we're beyond the current DMA window, indicate 316 * that and try to fall back into SGMAPs. 317 */ 318 if (t->_wsize != 0 && lastaddr >= t->_wsize) { 319 error = EINVAL; 320 break; 321 } 322 lastaddr |= t->_wbase; 323 324 map->dm_segs[seg].ds_addr = lastaddr; 325 map->dm_segs[seg].ds_len = m->m_len; 326 lastaddr += m->m_len; 327 break; 328 329 case 0: 330 lastaddr = m->m_paddr + M_BUFOFFSET(m) + 331 (m->m_data - M_BUFADDR(m)); 332 goto have_addr; 333 334 default: 335 error = _bus_dmamap_load_buffer_direct(t, map, 336 m->m_data, m->m_len, NULL, flags, &lastaddr, 337 &seg, first); 338 } 339 first = 0; 340 } 341 if (error == 0) { 342 map->dm_mapsize = m0->m_pkthdr.len; 343 map->dm_nsegs = seg + 1; 344 map->_dm_window = t; 345 } else if (t->_next_window != NULL) { 346 /* 347 * Give the next window a chance. 348 */ 349 error = bus_dmamap_load_mbuf(t->_next_window, map, m0, flags); 350 } 351 return (error); 352} 353 354/* 355 * Like _bus_dmamap_load_direct(), but for uios. 356 */ 357int 358_bus_dmamap_load_uio_direct(bus_dma_tag_t t, bus_dmamap_t map, 359 struct uio *uio, int flags) 360{ 361 paddr_t lastaddr; 362 int seg, i, error, first; 363 bus_size_t minlen, resid; 364 struct proc *p = NULL; 365 struct iovec *iov; 366 caddr_t addr; 367 368 /* 369 * Make sure that on error condition we return "no valid mappings." 370 */ 371 map->dm_mapsize = 0; 372 map->dm_nsegs = 0; 373 KASSERT(map->dm_maxsegsz <= map->_dm_maxmaxsegsz); 374 375 resid = uio->uio_resid; 376 iov = uio->uio_iov; 377 378 if (uio->uio_segflg == UIO_USERSPACE) { 379 p = uio->uio_procp; 380#ifdef DIAGNOSTIC 381 if (p == NULL) 382 panic("_bus_dmamap_load_uio_direct: " 383 "USERSPACE but no proc"); 384#endif 385 } 386 387 first = 1; 388 seg = 0; 389 error = 0; 390 for (i = 0; i < uio->uio_iovcnt && resid != 0 && error == 0; i++) { 391 /* 392 * Now at the first iovec to load. Load each iovec 393 * until we have exhausted the residual count. 394 */ 395 minlen = resid < iov[i].iov_len ? resid : iov[i].iov_len; 396 addr = (caddr_t)iov[i].iov_base; 397 398 error = _bus_dmamap_load_buffer_direct(t, map, 399 addr, minlen, p, flags, &lastaddr, &seg, first); 400 first = 0; 401 402 resid -= minlen; 403 } 404 if (error == 0) { 405 map->dm_mapsize = uio->uio_resid; 406 map->dm_nsegs = seg + 1; 407 map->_dm_window = t; 408 } else if (t->_next_window != NULL) { 409 /* 410 * Give the next window a chance. 411 */ 412 error = bus_dmamap_load_uio(t->_next_window, map, uio, flags); 413 } 414 return (error); 415} 416 417/* 418 * Like _bus_dmamap_load_direct(), but for raw memory. 419 */ 420int 421_bus_dmamap_load_raw_direct(bus_dma_tag_t t, bus_dmamap_t map, 422 bus_dma_segment_t *segs, int nsegs, bus_size_t size, int flags) 423{ 424 425 panic("_bus_dmamap_load_raw_direct: not implemented"); 426} 427 428/* 429 * Common function for unloading a DMA map. May be called by 430 * chipset-specific DMA map unload functions. 431 */ 432void 433_bus_dmamap_unload(bus_dma_tag_t t, bus_dmamap_t map) 434{ 435 436 /* 437 * No resources to free; just mark the mappings as 438 * invalid. 439 */ 440 map->dm_maxsegsz = map->_dm_maxmaxsegsz; 441 map->dm_mapsize = 0; 442 map->dm_nsegs = 0; 443 map->_dm_window = NULL; 444} 445 446/* 447 * Common function for DMA map synchronization. May be called 448 * by chipset-specific DMA map synchronization functions. 449 */ 450void 451_bus_dmamap_sync(bus_dma_tag_t t, bus_dmamap_t map, bus_addr_t offset, 452 bus_size_t len, int ops) 453{ 454 455 /* 456 * Flush the store buffer. 457 */ 458 alpha_mb(); 459} 460 461/* 462 * Common function for DMA-safe memory allocation. May be called 463 * by bus-specific DMA memory allocation functions. 464 */ 465int 466_bus_dmamem_alloc(bus_dma_tag_t t, bus_size_t size, bus_size_t alignment, 467 bus_size_t boundary, bus_dma_segment_t *segs, int nsegs, int *rsegs, 468 int flags) 469{ 470 471 return (_bus_dmamem_alloc_range(t, size, alignment, boundary, 472 segs, nsegs, rsegs, flags, 0, trunc_page(avail_end))); 473} 474 475/* 476 * Allocate physical memory from the given physical address range. 477 * Called by DMA-safe memory allocation methods. 478 */ 479int 480_bus_dmamem_alloc_range(bus_dma_tag_t t, bus_size_t size, bus_size_t alignment, 481 bus_size_t boundary, bus_dma_segment_t *segs, int nsegs, int *rsegs, 482 int flags, paddr_t low, paddr_t high) 483{ 484 paddr_t curaddr, lastaddr; 485 struct vm_page *m; 486 struct pglist mlist; 487 int curseg, error; 488 489 /* Always round the size. */ 490 size = round_page(size); 491 492 /* 493 * Allocate pages from the VM system. 494 */ 495 error = uvm_pglistalloc(size, low, high, alignment, boundary, 496 &mlist, nsegs, (flags & BUS_DMA_NOWAIT) == 0); 497 if (error) 498 return (error); 499 500 /* 501 * Compute the location, size, and number of segments actually 502 * returned by the VM code. 503 */ 504 m = mlist.tqh_first; 505 curseg = 0; 506 lastaddr = segs[curseg].ds_addr = VM_PAGE_TO_PHYS(m); 507 segs[curseg].ds_len = PAGE_SIZE; 508 m = m->pageq.tqe_next; 509 510 for (; m != NULL; m = m->pageq.tqe_next) { 511 curaddr = VM_PAGE_TO_PHYS(m); 512#ifdef DIAGNOSTIC 513 if (curaddr < avail_start || curaddr >= high) { 514 printf("uvm_pglistalloc returned non-sensical" 515 " address 0x%lx\n", curaddr); 516 panic("_bus_dmamem_alloc"); 517 } 518#endif 519 if (curaddr == (lastaddr + PAGE_SIZE)) 520 segs[curseg].ds_len += PAGE_SIZE; 521 else { 522 curseg++; 523 segs[curseg].ds_addr = curaddr; 524 segs[curseg].ds_len = PAGE_SIZE; 525 } 526 lastaddr = curaddr; 527 } 528 529 *rsegs = curseg + 1; 530 531 return (0); 532} 533 534/* 535 * Common function for freeing DMA-safe memory. May be called by 536 * bus-specific DMA memory free functions. 537 */ 538void 539_bus_dmamem_free(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs) 540{ 541 struct vm_page *m; 542 bus_addr_t addr; 543 struct pglist mlist; 544 int curseg; 545 546 /* 547 * Build a list of pages to free back to the VM system. 548 */ 549 TAILQ_INIT(&mlist); 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 += PAGE_SIZE) { 554 m = PHYS_TO_VM_PAGE(addr); 555 TAILQ_INSERT_TAIL(&mlist, m, pageq); 556 } 557 } 558 559 uvm_pglistfree(&mlist); 560} 561 562/* 563 * Common function for mapping DMA-safe memory. May be called by 564 * bus-specific DMA memory map functions. 565 */ 566int 567_bus_dmamem_map(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs, 568 size_t size, caddr_t *kvap, int flags) 569{ 570 vaddr_t va; 571 bus_addr_t addr; 572 int curseg; 573 574 /* 575 * If we're only mapping 1 segment, use K0SEG, to avoid 576 * TLB thrashing. 577 */ 578 if (nsegs == 1) { 579 *kvap = (caddr_t)ALPHA_PHYS_TO_K0SEG(segs[0].ds_addr); 580 return (0); 581 } 582 583 size = round_page(size); 584 585 va = uvm_km_valloc(kernel_map, size); 586 587 if (va == 0) 588 return (ENOMEM); 589 590 *kvap = (caddr_t)va; 591 592 for (curseg = 0; curseg < nsegs; curseg++) { 593 for (addr = segs[curseg].ds_addr; 594 addr < (segs[curseg].ds_addr + segs[curseg].ds_len); 595 addr += PAGE_SIZE, va += PAGE_SIZE, size -= PAGE_SIZE) { 596 if (size == 0) 597 panic("_bus_dmamem_map: size botch"); 598 pmap_enter(pmap_kernel(), va, addr, 599 VM_PROT_READ | VM_PROT_WRITE, 600 PMAP_WIRED | VM_PROT_READ | VM_PROT_WRITE); 601 } 602 } 603 pmap_update(pmap_kernel()); 604 605 return (0); 606} 607 608/* 609 * Common function for unmapping DMA-safe memory. May be called by 610 * bus-specific DMA memory unmapping functions. 611 */ 612void 613_bus_dmamem_unmap(bus_dma_tag_t t, caddr_t kva, size_t size) 614{ 615 616#ifdef DIAGNOSTIC 617 if ((u_long)kva & PGOFSET) 618 panic("_bus_dmamem_unmap"); 619#endif 620 621 /* 622 * Nothing to do if we mapped it with K0SEG. 623 */ 624 if (kva >= (caddr_t)ALPHA_K0SEG_BASE && 625 kva <= (caddr_t)ALPHA_K0SEG_END) 626 return; 627 628 size = round_page(size); 629 uvm_km_free(kernel_map, (vaddr_t)kva, size); 630} 631 632/* 633 * Common functin for mmap(2)'ing DMA-safe memory. May be called by 634 * bus-specific DMA mmap(2)'ing functions. 635 */ 636paddr_t 637_bus_dmamem_mmap(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs, 638 off_t off, int prot, int flags) 639{ 640 int i; 641 642 for (i = 0; i < nsegs; i++) { 643#ifdef DIAGNOSTIC 644 if (off & PGOFSET) 645 panic("_bus_dmamem_mmap: offset unaligned"); 646 if (segs[i].ds_addr & PGOFSET) 647 panic("_bus_dmamem_mmap: segment unaligned"); 648 if (segs[i].ds_len & PGOFSET) 649 panic("_bus_dmamem_mmap: segment size not multiple" 650 " of page size"); 651#endif 652 if (off >= segs[i].ds_len) { 653 off -= segs[i].ds_len; 654 continue; 655 } 656 657 return (alpha_btop((caddr_t)segs[i].ds_addr + off)); 658 } 659 660 /* Page not found. */ 661 return (-1); 662} 663