sys/platform/pc32/i386/busdma_machdep.c

   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  * $FreeBSD: src/sys/i386/i386/busdma_machdep.c,v 1.16.2.2 2003/01/23 00:55:27 scottl Exp $
  27  * $DragonFly: src/sys/platform/pc32/i386/busdma_machdep.c,v 1.23 2008/06/05 18:06:32 swildner Exp $
  28  */
  29
  30 #include <sys/param.h>
  31 #include <sys/systm.h>
  32 #include <sys/malloc.h>
  33 #include <sys/mbuf.h>
  34 #include <sys/uio.h>
  35 #include <sys/thread2.h>
  36 #include <sys/bus_dma.h>
  37 #include <sys/kernel.h>
  38 #include <sys/sysctl.h>
  39
  40 #include <vm/vm.h>
  41 #include <vm/vm_page.h>
  42
  43 /* XXX needed for to access pmap to convert per-proc virtual to physical */
  44 #include <sys/proc.h>
  45 #include <sys/lock.h>
  46 #include <vm/vm_map.h>
  47
  48 #include <machine/md_var.h>
  49
  50 #define MAX_BPAGES      1024
  51
  52 struct bounce_zone;
  53
  54 struct bus_dma_tag {
  55         bus_dma_tag_t   parent;
  56         bus_size_t      alignment;
  57         bus_size_t      boundary;
  58         bus_addr_t      lowaddr;
  59         bus_addr_t      highaddr;
  60         bus_dma_filter_t *filter;
  61         void            *filterarg;
  62         bus_size_t      maxsize;
  63         u_int           nsegments;
  64         bus_size_t      maxsegsz;
  65         int             flags;
  66         int             ref_count;
  67         int             map_count;
  68         bus_dma_segment_t *segments;
  69         struct bounce_zone *bounce_zone;
  70 };
  71
  72 /*
  73  * bus_dma_tag private flags
  74  */
  75 #define BUS_DMA_COULD_BOUNCE    BUS_DMA_BUS3
  76 #define BUS_DMA_MIN_ALLOC_COMP  BUS_DMA_BUS4
  77
  78 struct bounce_page {
  79         vm_offset_t     vaddr;          /* kva of bounce buffer */
  80         bus_addr_t      busaddr;        /* Physical address */
  81         vm_offset_t     datavaddr;      /* kva of client data */
  82         bus_size_t      datacount;      /* client data count */
  83         STAILQ_ENTRY(bounce_page) links;
  84 };
  85
  86 struct bounce_zone {
  87         STAILQ_ENTRY(bounce_zone) links;
  88         STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
  89         int             total_bpages;
  90         int             free_bpages;
  91         int             reserved_bpages;
  92         int             active_bpages;
  93         int             total_bounced;
  94         int             total_deferred;
  95         bus_size_t      alignment;
  96         bus_size_t      boundary;
  97         bus_addr_t      lowaddr;
  98         char            zoneid[8];
  99         char            lowaddrid[20];
 100         struct sysctl_ctx_list sysctl_ctx;
 101         struct sysctl_oid *sysctl_tree;
 102 };
 103
 104 static int busdma_zonecount;
 105 static STAILQ_HEAD(, bounce_zone) bounce_zone_list =
 106         STAILQ_HEAD_INITIALIZER(bounce_zone_list);
 107
 108 int busdma_swi_pending;
 109 static int total_bounce_pages;
 110 static bus_addr_t bounce_lowaddr = BUS_SPACE_MAXADDR;
 111
 112 struct bus_dmamap {
 113         struct bp_list  bpages;
 114         int             pagesneeded;
 115         int             pagesreserved;
 116         bus_dma_tag_t   dmat;
 117         void            *buf;           /* unmapped buffer pointer */
 118         bus_size_t      buflen;         /* unmapped buffer length */
 119         bus_dmamap_callback_t *callback;
 120         void            *callback_arg;
 121         STAILQ_ENTRY(bus_dmamap) links;
 122 };
 123
 124 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist =
 125         STAILQ_HEAD_INITIALIZER(bounce_map_waitinglist);
 126
 127 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist =
 128         STAILQ_HEAD_INITIALIZER(bounce_map_callbacklist);
 129
 130 static struct bus_dmamap nobounce_dmamap;
 131
 132 static int              alloc_bounce_zone(bus_dma_tag_t);
 133 static int              alloc_bounce_pages(bus_dma_tag_t, u_int);
 134 static int              reserve_bounce_pages(bus_dma_tag_t, bus_dmamap_t, int);
 135 static bus_addr_t       add_bounce_page(bus_dma_tag_t, bus_dmamap_t,
 136                             vm_offset_t, bus_size_t);
 137 static void             free_bounce_page(bus_dma_tag_t, struct bounce_page *);
 138
 139 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
 140 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bounce_pages,
 141            0, "Total bounce pages");
 142
 143 static __inline int
 144 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
 145 {
 146         int retval;
 147
 148         retval = 0;
 149         do {
 150                 if (paddr > dmat->lowaddr
 151                  && paddr <= dmat->highaddr
 152                  && (dmat->filter == NULL
 153                   || (*dmat->filter)(dmat->filterarg, paddr) != 0))
 154                         retval = 1;
 155
 156                 dmat = dmat->parent;
 157         } while (retval == 0 && dmat != NULL);
 158         return (retval);
 159 }
 160
 161 /*
 162  * Allocate a device specific dma_tag.
 163  */
 164 int
 165 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
 166                    bus_size_t boundary, bus_addr_t lowaddr,
 167                    bus_addr_t highaddr, bus_dma_filter_t *filter,
 168                    void *filterarg, bus_size_t maxsize, int nsegments,
 169                    bus_size_t maxsegsz, int flags, bus_dma_tag_t *dmat)
 170 {
 171         bus_dma_tag_t newtag;
 172         int error = 0;
 173
 174         if (alignment == 0)
 175                 alignment = 1;
 176
 177         /* Return a NULL tag on failure */
 178         *dmat = NULL;
 179
 180         newtag = kmalloc(sizeof(*newtag), M_DEVBUF, M_INTWAIT);
 181
 182         newtag->parent = parent;
 183         newtag->alignment = alignment;
 184         newtag->boundary = boundary;
 185         newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
 186         newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
 187         newtag->filter = filter;
 188         newtag->filterarg = filterarg;
 189         newtag->maxsize = maxsize;
 190         newtag->nsegments = nsegments;
 191         newtag->maxsegsz = maxsegsz;
 192         newtag->flags = flags;
 193         newtag->ref_count = 1; /* Count ourself */
 194         newtag->map_count = 0;
 195         newtag->segments = NULL;
 196         newtag->bounce_zone = NULL;
 197
 198         /* Take into account any restrictions imposed by our parent tag */
 199         if (parent != NULL) {
 200                 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
 201                 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
 202
 203                 if (newtag->boundary == 0) {
 204                         newtag->boundary = parent->boundary;
 205                 } else if (parent->boundary != 0) {
 206                         newtag->boundary = MIN(parent->boundary,
 207                                                newtag->boundary);
 208                 }
 209
 210 #ifdef notyet
 211                 newtag->alignment = MAX(parent->alignment, newtag->alignment);
 212 #endif
 213
 214                 if (newtag->filter == NULL) {
 215                         /*
 216                          * Short circuit looking at our parent directly
 217                          * since we have encapsulated all of its information
 218                          */
 219                         newtag->filter = parent->filter;
 220                         newtag->filterarg = parent->filterarg;
 221                         newtag->parent = parent->parent;
 222                 }
 223                 if (newtag->parent != NULL)
 224                         parent->ref_count++;
 225         }
 226
 227         if (newtag->lowaddr < ptoa(Maxmem))
 228                 newtag->flags |= BUS_DMA_COULD_BOUNCE;
 229
 230         if ((newtag->flags & BUS_DMA_COULD_BOUNCE) &&
 231             (flags & BUS_DMA_ALLOCNOW) != 0) {
 232                 struct bounce_zone *bz;
 233
 234                 /* Must bounce */
 235
 236                 if (lowaddr > bounce_lowaddr) {
 237                         /*
 238                          * Go through the pool and kill any pages
 239                          * that don't reside below lowaddr.
 240                          */
 241                         panic("bus_dma_tag_create: page reallocation "
 242                               "not implemented");
 243                 }
 244
 245                 error = alloc_bounce_zone(newtag);
 246                 if (error)
 247                         goto back;
 248                 bz = newtag->bounce_zone;
 249
 250                 if (ptoa(bz->total_bpages) < maxsize) {
 251                         int pages;
 252
 253                         pages = atop(maxsize) - bz->total_bpages;
 254
 255                         /* Add pages to our bounce pool */
 256                         if (alloc_bounce_pages(newtag, pages) < pages)
 257                                 error = ENOMEM;
 258                 }
 259                 /* Performed initial allocation */
 260                 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
 261         }
 262 back:
 263         if (error)
 264                 kfree(newtag, M_DEVBUF);
 265         else
 266                 *dmat = newtag;
 267         return error;
 268 }
 269
 270 int
 271 bus_dma_tag_destroy(bus_dma_tag_t dmat)
 272 {
 273         if (dmat != NULL) {
 274                 if (dmat->map_count != 0)
 275                         return (EBUSY);
 276
 277                 while (dmat != NULL) {
 278                         bus_dma_tag_t parent;
 279
 280                         parent = dmat->parent;
 281                         dmat->ref_count--;
 282                         if (dmat->ref_count == 0) {
 283                                 if (dmat->segments != NULL)
 284                                         kfree(dmat->segments, M_DEVBUF);
 285                                 kfree(dmat, M_DEVBUF);
 286                                 /*
 287                                  * Last reference count, so
 288                                  * release our reference
 289                                  * count on our parent.
 290                                  */
 291                                 dmat = parent;
 292                         } else
 293                                 dmat = NULL;
 294                 }
 295         }
 296         return (0);
 297 }
 298
 299 /*
 300  * Allocate a handle for mapping from kva/uva/physical
 301  * address space into bus device space.
 302  */
 303 int
 304 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
 305 {
 306         int error;
 307
 308         error = 0;
 309
 310         if (dmat->segments == NULL) {
 311                 KKASSERT(dmat->nsegments && dmat->nsegments < 16384);
 312                 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) *
 313                                         dmat->nsegments, M_DEVBUF, M_INTWAIT);
 314         }
 315
 316         if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
 317                 struct bounce_zone *bz;
 318                 int maxpages;
 319
 320                 /* Must bounce */
 321
 322                 if (dmat->bounce_zone == NULL) {
 323                         error = alloc_bounce_zone(dmat);
 324                         if (error)
 325                                 return error;
 326                 }
 327                 bz = dmat->bounce_zone;
 328
 329                 *mapp = kmalloc(sizeof(**mapp), M_DEVBUF, M_INTWAIT | M_ZERO);
 330
 331                 /* Initialize the new map */
 332                 STAILQ_INIT(&((*mapp)->bpages));
 333                 /*
 334                  * Attempt to add pages to our pool on a per-instance
 335                  * basis up to a sane limit.
 336                  */
 337                 maxpages = MIN(MAX_BPAGES, Maxmem - atop(dmat->lowaddr));
 338                 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
 339                  || (dmat->map_count > 0
 340                   && bz->total_bpages < maxpages)) {
 341                         int pages;
 342
 343                         if (dmat->lowaddr > bounce_lowaddr) {
 344                                 /*
 345                                  * Go through the pool and kill any pages
 346                                  * that don't reside below lowaddr.
 347                                  */
 348                                 panic("bus_dmamap_create: page reallocation "
 349                                       "not implemented");
 350                         }
 351
 352                         pages = MAX(atop(dmat->maxsize), 1);
 353                         pages = MIN(maxpages - bz->total_bpages, pages);
 354                         pages = MAX(pages, 1);
 355                         if (alloc_bounce_pages(dmat, pages) < pages)
 356                                 error = ENOMEM;
 357
 358                         if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
 359                                 if (!error)
 360                                         dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
 361                         } else {
 362                                 error = 0;
 363                         }
 364                 }
 365         } else {
 366                 *mapp = NULL;
 367         }
 368         if (!error)
 369                 dmat->map_count++;
 370         return error;
 371 }
 372
 373 /*
 374  * Destroy a handle for mapping from kva/uva/physical
 375  * address space into bus device space.
 376  */
 377 int
 378 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
 379 {
 380         if (map != NULL) {
 381                 if (STAILQ_FIRST(&map->bpages) != NULL)
 382                         return (EBUSY);
 383                 kfree(map, M_DEVBUF);
 384         }
 385         dmat->map_count--;
 386         return (0);
 387 }
 388
 389 /*
 390  * Allocate a piece of memory that can be efficiently mapped into
 391  * bus device space based on the constraints lited in the dma tag.
 392  *
 393  * mapp is degenerate.  By definition this allocation should not require
 394  * bounce buffers so do not allocate a dma map.
 395  */
 396 int
 397 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
 398                  bus_dmamap_t *mapp)
 399 {
 400         int mflags;
 401
 402         /* If we succeed, no mapping/bouncing will be required */
 403         *mapp = NULL;
 404
 405         if (dmat->segments == NULL) {
 406                 KKASSERT(dmat->nsegments < 16384);
 407                 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) *
 408                                         dmat->nsegments, M_DEVBUF, M_INTWAIT);
 409         }
 410
 411         if (flags & BUS_DMA_NOWAIT)
 412                 mflags = M_NOWAIT;
 413         else
 414                 mflags = M_WAITOK;
 415         if (flags & BUS_DMA_ZERO)
 416                 mflags |= M_ZERO;
 417
 418         if ((dmat->maxsize <= PAGE_SIZE) &&
 419             dmat->lowaddr >= ptoa(Maxmem)) {
 420                 *vaddr = kmalloc(dmat->maxsize, M_DEVBUF, mflags);
 421                 /*
 422                  * XXX Check whether the allocation crossed a page boundary
 423                  * and retry with power-of-2 alignment in that case.
 424                  */
 425                 if ((((intptr_t)*vaddr) & PAGE_MASK) !=
 426                     (((intptr_t)*vaddr + dmat->maxsize) & PAGE_MASK)) {
 427                         size_t size;
 428
 429                         kfree(*vaddr, M_DEVBUF);
 430                         /* XXX check for overflow? */
 431                         for (size = 1; size <= dmat->maxsize; size <<= 1)
 432                                 ;
 433                         *vaddr = kmalloc(size, M_DEVBUF, mflags);
 434                 }
 435         } else {
 436                 /*
 437                  * XXX Use Contigmalloc until it is merged into this facility
 438                  *     and handles multi-seg allocations.  Nobody is doing
 439                  *     multi-seg allocations yet though.
 440                  */
 441                 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
 442                     0ul, dmat->lowaddr, dmat->alignment, dmat->boundary);
 443         }
 444         if (*vaddr == NULL)
 445                 return (ENOMEM);
 446         return (0);
 447 }
 448
 449 /*
 450  * Free a piece of memory and it's allociated dmamap, that was allocated
 451  * via bus_dmamem_alloc.  Make the same choice for free/contigfree.
 452  */
 453 void
 454 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
 455 {
 456         /*
 457          * dmamem does not need to be bounced, so the map should be
 458          * NULL
 459          */
 460         if (map != NULL)
 461                 panic("bus_dmamem_free: Invalid map freed\n");
 462         if ((dmat->maxsize <= PAGE_SIZE) &&
 463             dmat->lowaddr >= ptoa(Maxmem))
 464                 kfree(vaddr, M_DEVBUF);
 465         else
 466                 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
 467 }
 468
 469 static int
 470 _bus_dmamap_load_buffer2(bus_dma_tag_t dmat,
 471                         bus_dmamap_t map,
 472                         void *buf, bus_size_t buflen,
 473                         struct thread *td,
 474                         int flags,
 475                         vm_paddr_t *lastpaddrp,
 476                         int *segp,
 477                         int first)
 478 {
 479         vm_offset_t vaddr;
 480         vm_paddr_t paddr, nextpaddr;
 481         bus_dma_segment_t *sg;
 482         bus_addr_t bmask;
 483         int seg, error = 0;
 484
 485         if (map == NULL)
 486                 map = &nobounce_dmamap;
 487
 488         /*
 489          * If we are being called during a callback, pagesneeded will
 490          * be non-zero, so we can avoid doing the work twice.
 491          */
 492         if ((dmat->flags & BUS_DMA_COULD_BOUNCE) &&
 493             map != &nobounce_dmamap && map->pagesneeded == 0) {
 494                 vm_offset_t vendaddr;
 495
 496                 /*
 497                  * Count the number of bounce pages
 498                  * needed in order to complete this transfer
 499                  */
 500                 vaddr = (vm_offset_t)buf;
 501                 vendaddr = (vm_offset_t)buf + buflen;
 502
 503                 while (vaddr < vendaddr) {
 504                         paddr = pmap_kextract(vaddr);
 505                         if (run_filter(dmat, paddr) != 0)
 506                                 map->pagesneeded++;
 507                         vaddr += (PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK));
 508                 }
 509         }
 510
 511         /* Reserve Necessary Bounce Pages */
 512         if (map->pagesneeded != 0) {
 513                 crit_enter();
 514                 if (flags & BUS_DMA_NOWAIT) {
 515                         if (reserve_bounce_pages(dmat, map, 0) != 0) {
 516                                 crit_exit();
 517                                 return (ENOMEM);
 518                         }
 519                 } else {
 520                         if (reserve_bounce_pages(dmat, map, 1) != 0) {
 521                                 /* Queue us for resources */
 522                                 map->dmat = dmat;
 523                                 map->buf = buf;
 524                                 map->buflen = buflen;
 525
 526                                 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
 527                                                    map, links);
 528                                 crit_exit();
 529
 530                                 return (EINPROGRESS);
 531                         }
 532                 }
 533                 crit_exit();
 534         }
 535
 536         KKASSERT(*segp >= 1);
 537         seg = *segp;
 538         sg = &dmat->segments[seg - 1];
 539
 540         vaddr = (vm_offset_t)buf;
 541         nextpaddr = *lastpaddrp;
 542         bmask = ~(dmat->boundary - 1);  /* note: will be 0 if boundary is 0 */
 543
 544         /* force at least one segment */
 545         do {
 546                 bus_size_t size;
 547
 548                 /*
 549                  * Per-page main loop
 550                  */
 551                 paddr = pmap_kextract(vaddr);
 552                 size = PAGE_SIZE - (paddr & PAGE_MASK);
 553                 if (size > buflen)
 554                         size = buflen;
 555                 if (map->pagesneeded != 0 && run_filter(dmat, paddr)) {
 556                         /*
 557                          * note: this paddr has the same in-page offset
 558                          * as vaddr and thus the paddr above, so the
 559                          * size does not have to be recalculated
 560                          */
 561                         paddr = add_bounce_page(dmat, map, vaddr, size);
 562                 }
 563
 564                 /*
 565                  * Fill in the bus_dma_segment
 566                  */
 567                 if (first) {
 568                         sg->ds_addr = paddr;
 569                         sg->ds_len = size;
 570                         first = 0;
 571                 } else if (paddr == nextpaddr) {
 572                         sg->ds_len += size;
 573                 } else {
 574                         sg++;
 575                         seg++;
 576                         if (seg > dmat->nsegments)
 577                                 break;
 578                         sg->ds_addr = paddr;
 579                         sg->ds_len = size;
 580                 }
 581                 nextpaddr = paddr + size;
 582
 583                 /*
 584                  * Handle maxsegsz and boundary issues with a nested loop
 585                  */
 586                 for (;;) {
 587                         bus_size_t tmpsize;
 588
 589                         /*
 590                          * Limit to the boundary and maximum segment size
 591                          */
 592                         if (((nextpaddr - 1) ^ sg->ds_addr) & bmask) {
 593                                 tmpsize = dmat->boundary -
 594                                           (sg->ds_addr & ~bmask);
 595                                 if (tmpsize > dmat->maxsegsz)
 596                                         tmpsize = dmat->maxsegsz;
 597                                 KKASSERT(tmpsize < sg->ds_len);
 598                         } else if (sg->ds_len > dmat->maxsegsz) {
 599                                 tmpsize = dmat->maxsegsz;
 600                         } else {
 601                                 break;
 602                         }
 603
 604                         /*
 605                          * Futz, split the data into a new segment.
 606                          */
 607                         if (seg >= dmat->nsegments)
 608                                 goto fail;
 609                         sg[1].ds_len = sg[0].ds_len - tmpsize;
 610                         sg[1].ds_addr = sg[0].ds_addr + tmpsize;
 611                         sg[0].ds_len = tmpsize;
 612                         sg++;
 613                         seg++;
 614                 }
 615
 616                 /*
 617                  * Adjust for loop
 618                  */
 619                 buflen -= size;
 620                 vaddr += size;
 621         } while (buflen > 0);
 622 fail:
 623         if (buflen != 0) {
 624                 kprintf("bus_dmamap_load: Too many segs! buf_len = 0x%lx\n",
 625                        (u_long)buflen);
 626                 error = EFBIG;
 627         }
 628
 629         *segp = seg;
 630         *lastpaddrp = nextpaddr;
 631
 632         return error;
 633 }
 634
 635 /*
 636  * Map the buffer buf into bus space using the dmamap map.
 637  */
 638 int
 639 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
 640                 bus_size_t buflen, bus_dmamap_callback_t *callback,
 641                 void *callback_arg, int flags)
 642 {
 643         vm_paddr_t lastaddr = 0;
 644         int error, nsegs = 1;
 645
 646         if (map != NULL) {
 647                 /*
 648                  * XXX
 649                  * Follow old semantics.  Once all of the callers are fixed,
 650                  * we should get rid of these internal flag "adjustment".
 651                  */
 652                 flags &= ~BUS_DMA_NOWAIT;
 653                 flags |= BUS_DMA_WAITOK;
 654
 655                 map->callback = callback;
 656                 map->callback_arg = callback_arg;
 657         }
 658
 659         error = _bus_dmamap_load_buffer2(dmat, map,
 660                         buf, buflen, NULL, flags, &lastaddr, &nsegs, 1);
 661         if (error == EINPROGRESS)
 662                 return error;
 663
 664         callback(callback_arg, dmat->segments, nsegs, error);
 665         return 0;
 666 }
 667
 668 /*
 669  * Utility function to load a linear buffer.  lastaddrp holds state
 670  * between invocations (for multiple-buffer loads).  segp contains
 671  * the starting segment on entrace, and the ending segment on exit.
 672  * first indicates if this is the first invocation of this function.
 673  */
 674 static int
 675 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
 676                         void *buf, bus_size_t buflen,
 677                         struct thread *td,
 678                         int flags,
 679                         vm_offset_t *lastaddrp,
 680                         int *segp,
 681                         int first)
 682 {
 683         bus_dma_segment_t *segs;
 684         bus_size_t sgsize;
 685         bus_addr_t curaddr, lastaddr, baddr, bmask;
 686         vm_offset_t vaddr = (vm_offset_t)buf;
 687         int seg;
 688         pmap_t pmap;
 689
 690         if (td->td_proc != NULL)
 691                 pmap = vmspace_pmap(td->td_proc->p_vmspace);
 692         else
 693                 pmap = NULL;
 694
 695         segs = dmat->segments;
 696         lastaddr = *lastaddrp;
 697         bmask  = ~(dmat->boundary - 1);
 698
 699         for (seg = *segp; buflen > 0 ; ) {
 700                 /*
 701                  * Get the physical address for this segment.
 702                  */
 703                 if (pmap)
 704                         curaddr = pmap_extract(pmap, vaddr);
 705                 else
 706                         curaddr = pmap_kextract(vaddr);
 707
 708                 /*
 709                  * Compute the segment size, and adjust counts.
 710                  */
 711                 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK);
 712                 if (buflen < sgsize)
 713                         sgsize = buflen;
 714
 715                 /*
 716                  * Make sure we don't cross any boundaries.
 717                  */
 718                 if (dmat->boundary > 0) {
 719                         baddr = (curaddr + dmat->boundary) & bmask;
 720                         if (sgsize > (baddr - curaddr))
 721                                 sgsize = (baddr - curaddr);
 722                 }
 723
 724                 /*
 725                  * Insert chunk into a segment, coalescing with
 726                  * previous segment if possible.
 727                  */
 728                 if (first) {
 729                         segs[seg].ds_addr = curaddr;
 730                         segs[seg].ds_len = sgsize;
 731                         first = 0;
 732                 } else {
 733                         if (curaddr == lastaddr &&
 734                             (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
 735                             (dmat->boundary == 0 ||
 736                              (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
 737                                 segs[seg].ds_len += sgsize;
 738                         else {
 739                                 if (++seg >= dmat->nsegments)
 740                                         break;
 741                                 segs[seg].ds_addr = curaddr;
 742                                 segs[seg].ds_len = sgsize;
 743                         }
 744                 }
 745
 746                 lastaddr = curaddr + sgsize;
 747                 vaddr += sgsize;
 748                 buflen -= sgsize;
 749         }
 750
 751         *segp = seg;
 752         *lastaddrp = lastaddr;
 753
 754         /*
 755          * Did we fit?
 756          */
 757         return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
 758 }
 759
 760 /*
 761  * Like _bus_dmamap_load(), but for mbufs.
 762  */
 763 int
 764 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
 765                      struct mbuf *m0,
 766                      bus_dmamap_callback2_t *callback, void *callback_arg,
 767                      int flags)
 768 {
 769         int nsegs, error;
 770
 771         M_ASSERTPKTHDR(m0);
 772
 773         /*
 774          * XXX
 775          * Follow old semantics.  Once all of the callers are fixed,
 776          * we should get rid of these internal flag "adjustment".
 777          */
 778         flags &= ~BUS_DMA_WAITOK;
 779         flags |= BUS_DMA_NOWAIT;
 780
 781         if (m0->m_pkthdr.len <= dmat->maxsize) {
 782                 int first = 1;
 783                 vm_paddr_t lastaddr = 0;
 784                 struct mbuf *m;
 785
 786                 nsegs = 1;
 787                 error = 0;
 788                 for (m = m0; m != NULL && error == 0; m = m->m_next) {
 789                         if (m->m_len == 0)
 790                                 continue;
 791
 792                         error = _bus_dmamap_load_buffer2(dmat, map,
 793                                         m->m_data, m->m_len,
 794                                         NULL, flags, &lastaddr,
 795                                         &nsegs, first);
 796                         first = 0;
 797                 }
 798         } else {
 799                 nsegs = 0;
 800                 error = EINVAL;
 801         }
 802
 803         if (error) {
 804                 /* force "no valid mappings" in callback */
 805                 callback(callback_arg, dmat->segments, 0, 0, error);
 806         } else {
 807                 callback(callback_arg, dmat->segments, nsegs,
 808                          m0->m_pkthdr.len, error);
 809         }
 810         return error;
 811 }
 812
 813 /*
 814  * Like _bus_dmamap_load(), but for uios.
 815  */
 816 int
 817 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
 818                     struct uio *uio,
 819                     bus_dmamap_callback2_t *callback, void *callback_arg,
 820                     int flags)
 821 {
 822         vm_offset_t lastaddr = 0;
 823         int nsegs, error, first, i;
 824         bus_size_t resid;
 825         struct iovec *iov;
 826         struct thread *td = NULL;
 827
 828         KASSERT(dmat->lowaddr >= ptoa(Maxmem) || map != NULL,
 829                 ("bus_dmamap_load_uio: No support for bounce pages!"));
 830
 831         resid = uio->uio_resid;
 832         iov = uio->uio_iov;
 833
 834         if (uio->uio_segflg == UIO_USERSPACE) {
 835                 td = uio->uio_td;
 836                 KASSERT(td != NULL && td->td_proc != NULL,
 837                         ("bus_dmamap_load_uio: USERSPACE but no proc"));
 838         }
 839
 840         nsegs = 0;
 841         error = 0;
 842         first = 1;
 843         for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
 844                 /*
 845                  * Now at the first iovec to load.  Load each iovec
 846                  * until we have exhausted the residual count.
 847                  */
 848                 bus_size_t minlen =
 849                         resid < iov[i].iov_len ? resid : iov[i].iov_len;
 850                 caddr_t addr = (caddr_t) iov[i].iov_base;
 851
 852                 error = _bus_dmamap_load_buffer(dmat,
 853                                 addr, minlen,
 854                                 td, flags, &lastaddr, &nsegs, first);
 855                 first = 0;
 856
 857                 resid -= minlen;
 858         }
 859
 860         if (error) {
 861                 /* force "no valid mappings" in callback */
 862                 (*callback)(callback_arg, dmat->segments, 0, 0, error);
 863         } else {
 864                 (*callback)(callback_arg, dmat->segments,
 865                             nsegs+1, uio->uio_resid, error);
 866         }
 867         return (error);
 868 }
 869
 870 /*
 871  * Release the mapping held by map.
 872  */
 873 void
 874 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
 875 {
 876         struct bounce_page *bpage;
 877
 878         while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
 879                 STAILQ_REMOVE_HEAD(&map->bpages, links);
 880                 free_bounce_page(dmat, bpage);
 881         }
 882 }
 883
 884 void
 885 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
 886 {
 887         struct bounce_page *bpage;
 888
 889         if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
 890                 /*
 891                  * Handle data bouncing.  We might also
 892                  * want to add support for invalidating
 893                  * the caches on broken hardware
 894                  */
 895                 switch (op) {
 896                 case BUS_DMASYNC_PREWRITE:
 897                         while (bpage != NULL) {
 898                                 bcopy((void *)bpage->datavaddr,
 899                                       (void *)bpage->vaddr,
 900                                       bpage->datacount);
 901                                 bpage = STAILQ_NEXT(bpage, links);
 902                         }
 903                         dmat->bounce_zone->total_bounced++;
 904                         break;
 905
 906                 case BUS_DMASYNC_POSTREAD:
 907                         while (bpage != NULL) {
 908                                 bcopy((void *)bpage->vaddr,
 909                                       (void *)bpage->datavaddr,
 910                                       bpage->datacount);
 911                                 bpage = STAILQ_NEXT(bpage, links);
 912                         }
 913                         dmat->bounce_zone->total_bounced++;
 914                         break;
 915
 916                 case BUS_DMASYNC_PREREAD:
 917                 case BUS_DMASYNC_POSTWRITE:
 918                         /* No-ops */
 919                         break;
 920                 }
 921         }
 922 }
 923
 924 static int
 925 alloc_bounce_zone(bus_dma_tag_t dmat)
 926 {
 927         struct bounce_zone *bz;
 928
 929         KASSERT(dmat->bounce_zone == NULL,
 930                 ("bounce zone was already assigned\n"));
 931
 932         /* Check to see if we already have a suitable zone */
 933         STAILQ_FOREACH(bz, &bounce_zone_list, links) {
 934                 if (dmat->alignment <= bz->alignment &&
 935                     dmat->boundary <= bz->boundary &&
 936                     dmat->lowaddr >= bz->lowaddr) {
 937                         dmat->bounce_zone = bz;
 938                         return 0;
 939                 }
 940         }
 941
 942         bz = kmalloc(sizeof(*bz), M_DEVBUF, M_INTWAIT | M_ZERO);
 943
 944         STAILQ_INIT(&bz->bounce_page_list);
 945         bz->free_bpages = 0;
 946         bz->reserved_bpages = 0;
 947         bz->active_bpages = 0;
 948         bz->lowaddr = dmat->lowaddr;
 949         bz->alignment = dmat->alignment;
 950         bz->boundary = dmat->boundary;
 951         ksnprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
 952         busdma_zonecount++;
 953         ksnprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
 954         STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
 955         dmat->bounce_zone = bz;
 956
 957         sysctl_ctx_init(&bz->sysctl_ctx);
 958         bz->sysctl_tree = SYSCTL_ADD_NODE(&bz->sysctl_ctx,
 959             SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
 960             CTLFLAG_RD, 0, "");
 961         if (bz->sysctl_tree == NULL) {
 962                 sysctl_ctx_free(&bz->sysctl_ctx);
 963                 return 0;       /* XXX error code? */
 964         }
 965
 966         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 967             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 968             "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
 969             "Total bounce pages");
 970         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 971             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 972             "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
 973             "Free bounce pages");
 974         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 975             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 976             "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
 977             "Reserved bounce pages");
 978         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 979             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 980             "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
 981             "Active bounce pages");
 982         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 983             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 984             "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
 985             "Total bounce requests");
 986         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 987             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 988             "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
 989             "Total bounce requests that were deferred");
 990         SYSCTL_ADD_STRING(&bz->sysctl_ctx,
 991             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 992             "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
 993         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 994             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 995             "alignment", CTLFLAG_RD, &bz->alignment, 0, "");
 996         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 997             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 998             "boundary", CTLFLAG_RD, &bz->boundary, 0, "");
 999
1000         return 0;
1001 }
1002
1003 static int
1004 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1005 {
1006         struct bounce_zone *bz = dmat->bounce_zone;
1007         int count = 0;
1008
1009         while (numpages > 0) {
1010                 struct bounce_page *bpage;
1011
1012                 bpage = kmalloc(sizeof(*bpage), M_DEVBUF, M_INTWAIT | M_ZERO);
1013
1014                 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1015                                                          M_NOWAIT, 0ul,
1016                                                          dmat->lowaddr,
1017                                                          PAGE_SIZE,
1018                                                          0);
1019                 if (bpage->vaddr == 0) {
1020                         kfree(bpage, M_DEVBUF);
1021                         break;
1022                 }
1023                 bpage->busaddr = pmap_kextract(bpage->vaddr);
1024
1025                 crit_enter();
1026                 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1027                 total_bounce_pages++;
1028                 bz->total_bpages++;
1029                 bz->free_bpages++;
1030                 crit_exit();
1031
1032                 count++;
1033                 numpages--;
1034         }
1035         return count;
1036 }
1037
1038 static int
1039 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1040 {
1041         struct bounce_zone *bz = dmat->bounce_zone;
1042         int pages;
1043
1044         pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1045         if (!commit && map->pagesneeded > (map->pagesreserved + pages))
1046                 return (map->pagesneeded - (map->pagesreserved + pages));
1047         bz->free_bpages -= pages;
1048         bz->reserved_bpages += pages;
1049         map->pagesreserved += pages;
1050         pages = map->pagesneeded - map->pagesreserved;
1051
1052         return pages;
1053 }
1054
1055 static bus_addr_t
1056 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1057                 bus_size_t size)
1058 {
1059         struct bounce_zone *bz = dmat->bounce_zone;
1060         struct bounce_page *bpage;
1061
1062         if (map->pagesneeded == 0)
1063                 panic("add_bounce_page: map doesn't need any pages");
1064         map->pagesneeded--;
1065
1066         if (map->pagesreserved == 0)
1067                 panic("add_bounce_page: map doesn't need any pages");
1068         map->pagesreserved--;
1069
1070         crit_enter();
1071         bpage = STAILQ_FIRST(&bz->bounce_page_list);
1072         if (bpage == NULL)
1073                 panic("add_bounce_page: free page list is empty");
1074
1075         STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1076         bz->reserved_bpages--;
1077         bz->active_bpages++;
1078         crit_exit();
1079
1080         bpage->datavaddr = vaddr;
1081         bpage->datacount = size;
1082         STAILQ_INSERT_TAIL(&map->bpages, bpage, links);
1083         return bpage->busaddr;
1084 }
1085
1086 static void
1087 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1088 {
1089         struct bounce_zone *bz = dmat->bounce_zone;
1090         struct bus_dmamap *map;
1091
1092         bpage->datavaddr = 0;
1093         bpage->datacount = 0;
1094
1095         crit_enter();
1096         STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1097         bz->free_bpages++;
1098         bz->active_bpages--;
1099         if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1100                 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1101                         STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1102                         STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1103                                            map, links);
1104                         busdma_swi_pending = 1;
1105                         bz->total_deferred++;
1106                         setsoftvm();
1107                 }
1108         }
1109         crit_exit();
1110 }
1111
1112 void
1113 busdma_swi(void)
1114 {
1115         struct bus_dmamap *map;
1116
1117         crit_enter();
1118         while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1119                 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1120                 crit_exit();
1121                 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
1122                                 map->callback, map->callback_arg, /*flags*/0);
1123                 crit_enter();
1124         }
1125         crit_exit();
1126 }