1 /* iommu.c: Generic sparc64 IOMMU support. 2 * 3 * Copyright (C) 1999, 2007, 2008 David S. Miller (davem@davemloft.net) 4 * Copyright (C) 1999, 2000 Jakub Jelinek (jakub@redhat.com) 5 */ 6 7 #include <linux/kernel.h> 8 #include <linux/export.h> 9 #include <linux/slab.h> 10 #include <linux/delay.h> 11 #include <linux/device.h> 12 #include <linux/dma-mapping.h> 13 #include <linux/errno.h> 14 #include <linux/iommu-helper.h> 15 #include <linux/bitmap.h> 16 17 #ifdef CONFIG_PCI 18 #include <linux/pci.h> 19 #endif 20 21 #include <asm/iommu.h> 22 23 #include "iommu_common.h" 24 25 #define STC_CTXMATCH_ADDR(STC, CTX) \ 26 ((STC)->strbuf_ctxmatch_base + ((CTX) << 3)) 27 #define STC_FLUSHFLAG_INIT(STC) \ 28 (*((STC)->strbuf_flushflag) = 0UL) 29 #define STC_FLUSHFLAG_SET(STC) \ 30 (*((STC)->strbuf_flushflag) != 0UL) 31 32 #define iommu_read(__reg) \ 33 ({ u64 __ret; \ 34 __asm__ __volatile__("ldxa [%1] %2, %0" \ 35 : "=r" (__ret) \ 36 : "r" (__reg), "i" (ASI_PHYS_BYPASS_EC_E) \ 37 : "memory"); \ 38 __ret; \ 39 }) 40 #define iommu_write(__reg, __val) \ 41 __asm__ __volatile__("stxa %0, [%1] %2" \ 42 : /* no outputs */ \ 43 : "r" (__val), "r" (__reg), \ 44 "i" (ASI_PHYS_BYPASS_EC_E)) 45 46 /* Must be invoked under the IOMMU lock. */ 47 static void iommu_flushall(struct iommu *iommu) 48 { 49 if (iommu->iommu_flushinv) { 50 iommu_write(iommu->iommu_flushinv, ~(u64)0); 51 } else { 52 unsigned long tag; 53 int entry; 54 55 tag = iommu->iommu_tags; 56 for (entry = 0; entry < 16; entry++) { 57 iommu_write(tag, 0); 58 tag += 8; 59 } 60 61 /* Ensure completion of previous PIO writes. */ 62 (void) iommu_read(iommu->write_complete_reg); 63 } 64 } 65 66 #define IOPTE_CONSISTENT(CTX) \ 67 (IOPTE_VALID | IOPTE_CACHE | \ 68 (((CTX) << 47) & IOPTE_CONTEXT)) 69 70 #define IOPTE_STREAMING(CTX) \ 71 (IOPTE_CONSISTENT(CTX) | IOPTE_STBUF) 72 73 /* Existing mappings are never marked invalid, instead they 74 * are pointed to a dummy page. 75 */ 76 #define IOPTE_IS_DUMMY(iommu, iopte) \ 77 ((iopte_val(*iopte) & IOPTE_PAGE) == (iommu)->dummy_page_pa) 78 79 static inline void iopte_make_dummy(struct iommu *iommu, iopte_t *iopte) 80 { 81 unsigned long val = iopte_val(*iopte); 82 83 val &= ~IOPTE_PAGE; 84 val |= iommu->dummy_page_pa; 85 86 iopte_val(*iopte) = val; 87 } 88 89 /* Based almost entirely upon the ppc64 iommu allocator. If you use the 'handle' 90 * facility it must all be done in one pass while under the iommu lock. 91 * 92 * On sun4u platforms, we only flush the IOMMU once every time we've passed 93 * over the entire page table doing allocations. Therefore we only ever advance 94 * the hint and cannot backtrack it. 95 */ 96 unsigned long iommu_range_alloc(struct device *dev, 97 struct iommu *iommu, 98 unsigned long npages, 99 unsigned long *handle) 100 { 101 unsigned long n, end, start, limit, boundary_size; 102 struct iommu_arena *arena = &iommu->arena; 103 int pass = 0; 104 105 /* This allocator was derived from x86_64's bit string search */ 106 107 /* Sanity check */ 108 if (unlikely(npages == 0)) { 109 if (printk_ratelimit()) 110 WARN_ON(1); 111 return DMA_ERROR_CODE; 112 } 113 114 if (handle && *handle) 115 start = *handle; 116 else 117 start = arena->hint; 118 119 limit = arena->limit; 120 121 /* The case below can happen if we have a small segment appended 122 * to a large, or when the previous alloc was at the very end of 123 * the available space. If so, go back to the beginning and flush. 124 */ 125 if (start >= limit) { 126 start = 0; 127 if (iommu->flush_all) 128 iommu->flush_all(iommu); 129 } 130 131 again: 132 133 if (dev) 134 boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1, 135 1 << IO_PAGE_SHIFT); 136 else 137 boundary_size = ALIGN(1UL << 32, 1 << IO_PAGE_SHIFT); 138 139 n = iommu_area_alloc(arena->map, limit, start, npages, 140 iommu->page_table_map_base >> IO_PAGE_SHIFT, 141 boundary_size >> IO_PAGE_SHIFT, 0); 142 if (n == -1) { 143 if (likely(pass < 1)) { 144 /* First failure, rescan from the beginning. */ 145 start = 0; 146 if (iommu->flush_all) 147 iommu->flush_all(iommu); 148 pass++; 149 goto again; 150 } else { 151 /* Second failure, give up */ 152 return DMA_ERROR_CODE; 153 } 154 } 155 156 end = n + npages; 157 158 arena->hint = end; 159 160 /* Update handle for SG allocations */ 161 if (handle) 162 *handle = end; 163 164 return n; 165 } 166 167 void iommu_range_free(struct iommu *iommu, dma_addr_t dma_addr, unsigned long npages) 168 { 169 struct iommu_arena *arena = &iommu->arena; 170 unsigned long entry; 171 172 entry = (dma_addr - iommu->page_table_map_base) >> IO_PAGE_SHIFT; 173 174 bitmap_clear(arena->map, entry, npages); 175 } 176 177 int iommu_table_init(struct iommu *iommu, int tsbsize, 178 u32 dma_offset, u32 dma_addr_mask, 179 int numa_node) 180 { 181 unsigned long i, order, sz, num_tsb_entries; 182 struct page *page; 183 184 num_tsb_entries = tsbsize / sizeof(iopte_t); 185 186 /* Setup initial software IOMMU state. */ 187 spin_lock_init(&iommu->lock); 188 iommu->ctx_lowest_free = 1; 189 iommu->page_table_map_base = dma_offset; 190 iommu->dma_addr_mask = dma_addr_mask; 191 192 /* Allocate and initialize the free area map. */ 193 sz = num_tsb_entries / 8; 194 sz = (sz + 7UL) & ~7UL; 195 iommu->arena.map = kmalloc_node(sz, GFP_KERNEL, numa_node); 196 if (!iommu->arena.map) { 197 printk(KERN_ERR "IOMMU: Error, kmalloc(arena.map) failed.\n"); 198 return -ENOMEM; 199 } 200 memset(iommu->arena.map, 0, sz); 201 iommu->arena.limit = num_tsb_entries; 202 203 if (tlb_type != hypervisor) 204 iommu->flush_all = iommu_flushall; 205 206 /* Allocate and initialize the dummy page which we 207 * set inactive IO PTEs to point to. 208 */ 209 page = alloc_pages_node(numa_node, GFP_KERNEL, 0); 210 if (!page) { 211 printk(KERN_ERR "IOMMU: Error, gfp(dummy_page) failed.\n"); 212 goto out_free_map; 213 } 214 iommu->dummy_page = (unsigned long) page_address(page); 215 memset((void *)iommu->dummy_page, 0, PAGE_SIZE); 216 iommu->dummy_page_pa = (unsigned long) __pa(iommu->dummy_page); 217 218 /* Now allocate and setup the IOMMU page table itself. */ 219 order = get_order(tsbsize); 220 page = alloc_pages_node(numa_node, GFP_KERNEL, order); 221 if (!page) { 222 printk(KERN_ERR "IOMMU: Error, gfp(tsb) failed.\n"); 223 goto out_free_dummy_page; 224 } 225 iommu->page_table = (iopte_t *)page_address(page); 226 227 for (i = 0; i < num_tsb_entries; i++) 228 iopte_make_dummy(iommu, &iommu->page_table[i]); 229 230 return 0; 231 232 out_free_dummy_page: 233 free_page(iommu->dummy_page); 234 iommu->dummy_page = 0UL; 235 236 out_free_map: 237 kfree(iommu->arena.map); 238 iommu->arena.map = NULL; 239 240 return -ENOMEM; 241 } 242 243 static inline iopte_t *alloc_npages(struct device *dev, struct iommu *iommu, 244 unsigned long npages) 245 { 246 unsigned long entry; 247 248 entry = iommu_range_alloc(dev, iommu, npages, NULL); 249 if (unlikely(entry == DMA_ERROR_CODE)) 250 return NULL; 251 252 return iommu->page_table + entry; 253 } 254 255 static int iommu_alloc_ctx(struct iommu *iommu) 256 { 257 int lowest = iommu->ctx_lowest_free; 258 int n = find_next_zero_bit(iommu->ctx_bitmap, IOMMU_NUM_CTXS, lowest); 259 260 if (unlikely(n == IOMMU_NUM_CTXS)) { 261 n = find_next_zero_bit(iommu->ctx_bitmap, lowest, 1); 262 if (unlikely(n == lowest)) { 263 printk(KERN_WARNING "IOMMU: Ran out of contexts.\n"); 264 n = 0; 265 } 266 } 267 if (n) 268 __set_bit(n, iommu->ctx_bitmap); 269 270 return n; 271 } 272 273 static inline void iommu_free_ctx(struct iommu *iommu, int ctx) 274 { 275 if (likely(ctx)) { 276 __clear_bit(ctx, iommu->ctx_bitmap); 277 if (ctx < iommu->ctx_lowest_free) 278 iommu->ctx_lowest_free = ctx; 279 } 280 } 281 282 static void *dma_4u_alloc_coherent(struct device *dev, size_t size, 283 dma_addr_t *dma_addrp, gfp_t gfp, 284 struct dma_attrs *attrs) 285 { 286 unsigned long flags, order, first_page; 287 struct iommu *iommu; 288 struct page *page; 289 int npages, nid; 290 iopte_t *iopte; 291 void *ret; 292 293 size = IO_PAGE_ALIGN(size); 294 order = get_order(size); 295 if (order >= 10) 296 return NULL; 297 298 nid = dev->archdata.numa_node; 299 page = alloc_pages_node(nid, gfp, order); 300 if (unlikely(!page)) 301 return NULL; 302 303 first_page = (unsigned long) page_address(page); 304 memset((char *)first_page, 0, PAGE_SIZE << order); 305 306 iommu = dev->archdata.iommu; 307 308 spin_lock_irqsave(&iommu->lock, flags); 309 iopte = alloc_npages(dev, iommu, size >> IO_PAGE_SHIFT); 310 spin_unlock_irqrestore(&iommu->lock, flags); 311 312 if (unlikely(iopte == NULL)) { 313 free_pages(first_page, order); 314 return NULL; 315 } 316 317 *dma_addrp = (iommu->page_table_map_base + 318 ((iopte - iommu->page_table) << IO_PAGE_SHIFT)); 319 ret = (void *) first_page; 320 npages = size >> IO_PAGE_SHIFT; 321 first_page = __pa(first_page); 322 while (npages--) { 323 iopte_val(*iopte) = (IOPTE_CONSISTENT(0UL) | 324 IOPTE_WRITE | 325 (first_page & IOPTE_PAGE)); 326 iopte++; 327 first_page += IO_PAGE_SIZE; 328 } 329 330 return ret; 331 } 332 333 static void dma_4u_free_coherent(struct device *dev, size_t size, 334 void *cpu, dma_addr_t dvma, 335 struct dma_attrs *attrs) 336 { 337 struct iommu *iommu; 338 unsigned long flags, order, npages; 339 340 npages = IO_PAGE_ALIGN(size) >> IO_PAGE_SHIFT; 341 iommu = dev->archdata.iommu; 342 343 spin_lock_irqsave(&iommu->lock, flags); 344 345 iommu_range_free(iommu, dvma, npages); 346 347 spin_unlock_irqrestore(&iommu->lock, flags); 348 349 order = get_order(size); 350 if (order < 10) 351 free_pages((unsigned long)cpu, order); 352 } 353 354 static dma_addr_t dma_4u_map_page(struct device *dev, struct page *page, 355 unsigned long offset, size_t sz, 356 enum dma_data_direction direction, 357 struct dma_attrs *attrs) 358 { 359 struct iommu *iommu; 360 struct strbuf *strbuf; 361 iopte_t *base; 362 unsigned long flags, npages, oaddr; 363 unsigned long i, base_paddr, ctx; 364 u32 bus_addr, ret; 365 unsigned long iopte_protection; 366 367 iommu = dev->archdata.iommu; 368 strbuf = dev->archdata.stc; 369 370 if (unlikely(direction == DMA_NONE)) 371 goto bad_no_ctx; 372 373 oaddr = (unsigned long)(page_address(page) + offset); 374 npages = IO_PAGE_ALIGN(oaddr + sz) - (oaddr & IO_PAGE_MASK); 375 npages >>= IO_PAGE_SHIFT; 376 377 spin_lock_irqsave(&iommu->lock, flags); 378 base = alloc_npages(dev, iommu, npages); 379 ctx = 0; 380 if (iommu->iommu_ctxflush) 381 ctx = iommu_alloc_ctx(iommu); 382 spin_unlock_irqrestore(&iommu->lock, flags); 383 384 if (unlikely(!base)) 385 goto bad; 386 387 bus_addr = (iommu->page_table_map_base + 388 ((base - iommu->page_table) << IO_PAGE_SHIFT)); 389 ret = bus_addr | (oaddr & ~IO_PAGE_MASK); 390 base_paddr = __pa(oaddr & IO_PAGE_MASK); 391 if (strbuf->strbuf_enabled) 392 iopte_protection = IOPTE_STREAMING(ctx); 393 else 394 iopte_protection = IOPTE_CONSISTENT(ctx); 395 if (direction != DMA_TO_DEVICE) 396 iopte_protection |= IOPTE_WRITE; 397 398 for (i = 0; i < npages; i++, base++, base_paddr += IO_PAGE_SIZE) 399 iopte_val(*base) = iopte_protection | base_paddr; 400 401 return ret; 402 403 bad: 404 iommu_free_ctx(iommu, ctx); 405 bad_no_ctx: 406 if (printk_ratelimit()) 407 WARN_ON(1); 408 return DMA_ERROR_CODE; 409 } 410 411 static void strbuf_flush(struct strbuf *strbuf, struct iommu *iommu, 412 u32 vaddr, unsigned long ctx, unsigned long npages, 413 enum dma_data_direction direction) 414 { 415 int limit; 416 417 if (strbuf->strbuf_ctxflush && 418 iommu->iommu_ctxflush) { 419 unsigned long matchreg, flushreg; 420 u64 val; 421 422 flushreg = strbuf->strbuf_ctxflush; 423 matchreg = STC_CTXMATCH_ADDR(strbuf, ctx); 424 425 iommu_write(flushreg, ctx); 426 val = iommu_read(matchreg); 427 val &= 0xffff; 428 if (!val) 429 goto do_flush_sync; 430 431 while (val) { 432 if (val & 0x1) 433 iommu_write(flushreg, ctx); 434 val >>= 1; 435 } 436 val = iommu_read(matchreg); 437 if (unlikely(val)) { 438 printk(KERN_WARNING "strbuf_flush: ctx flush " 439 "timeout matchreg[%llx] ctx[%lx]\n", 440 val, ctx); 441 goto do_page_flush; 442 } 443 } else { 444 unsigned long i; 445 446 do_page_flush: 447 for (i = 0; i < npages; i++, vaddr += IO_PAGE_SIZE) 448 iommu_write(strbuf->strbuf_pflush, vaddr); 449 } 450 451 do_flush_sync: 452 /* If the device could not have possibly put dirty data into 453 * the streaming cache, no flush-flag synchronization needs 454 * to be performed. 455 */ 456 if (direction == DMA_TO_DEVICE) 457 return; 458 459 STC_FLUSHFLAG_INIT(strbuf); 460 iommu_write(strbuf->strbuf_fsync, strbuf->strbuf_flushflag_pa); 461 (void) iommu_read(iommu->write_complete_reg); 462 463 limit = 100000; 464 while (!STC_FLUSHFLAG_SET(strbuf)) { 465 limit--; 466 if (!limit) 467 break; 468 udelay(1); 469 rmb(); 470 } 471 if (!limit) 472 printk(KERN_WARNING "strbuf_flush: flushflag timeout " 473 "vaddr[%08x] ctx[%lx] npages[%ld]\n", 474 vaddr, ctx, npages); 475 } 476 477 static void dma_4u_unmap_page(struct device *dev, dma_addr_t bus_addr, 478 size_t sz, enum dma_data_direction direction, 479 struct dma_attrs *attrs) 480 { 481 struct iommu *iommu; 482 struct strbuf *strbuf; 483 iopte_t *base; 484 unsigned long flags, npages, ctx, i; 485 486 if (unlikely(direction == DMA_NONE)) { 487 if (printk_ratelimit()) 488 WARN_ON(1); 489 return; 490 } 491 492 iommu = dev->archdata.iommu; 493 strbuf = dev->archdata.stc; 494 495 npages = IO_PAGE_ALIGN(bus_addr + sz) - (bus_addr & IO_PAGE_MASK); 496 npages >>= IO_PAGE_SHIFT; 497 base = iommu->page_table + 498 ((bus_addr - iommu->page_table_map_base) >> IO_PAGE_SHIFT); 499 bus_addr &= IO_PAGE_MASK; 500 501 spin_lock_irqsave(&iommu->lock, flags); 502 503 /* Record the context, if any. */ 504 ctx = 0; 505 if (iommu->iommu_ctxflush) 506 ctx = (iopte_val(*base) & IOPTE_CONTEXT) >> 47UL; 507 508 /* Step 1: Kick data out of streaming buffers if necessary. */ 509 if (strbuf->strbuf_enabled) 510 strbuf_flush(strbuf, iommu, bus_addr, ctx, 511 npages, direction); 512 513 /* Step 2: Clear out TSB entries. */ 514 for (i = 0; i < npages; i++) 515 iopte_make_dummy(iommu, base + i); 516 517 iommu_range_free(iommu, bus_addr, npages); 518 519 iommu_free_ctx(iommu, ctx); 520 521 spin_unlock_irqrestore(&iommu->lock, flags); 522 } 523 524 static int dma_4u_map_sg(struct device *dev, struct scatterlist *sglist, 525 int nelems, enum dma_data_direction direction, 526 struct dma_attrs *attrs) 527 { 528 struct scatterlist *s, *outs, *segstart; 529 unsigned long flags, handle, prot, ctx; 530 dma_addr_t dma_next = 0, dma_addr; 531 unsigned int max_seg_size; 532 unsigned long seg_boundary_size; 533 int outcount, incount, i; 534 struct strbuf *strbuf; 535 struct iommu *iommu; 536 unsigned long base_shift; 537 538 BUG_ON(direction == DMA_NONE); 539 540 iommu = dev->archdata.iommu; 541 strbuf = dev->archdata.stc; 542 if (nelems == 0 || !iommu) 543 return 0; 544 545 spin_lock_irqsave(&iommu->lock, flags); 546 547 ctx = 0; 548 if (iommu->iommu_ctxflush) 549 ctx = iommu_alloc_ctx(iommu); 550 551 if (strbuf->strbuf_enabled) 552 prot = IOPTE_STREAMING(ctx); 553 else 554 prot = IOPTE_CONSISTENT(ctx); 555 if (direction != DMA_TO_DEVICE) 556 prot |= IOPTE_WRITE; 557 558 outs = s = segstart = &sglist[0]; 559 outcount = 1; 560 incount = nelems; 561 handle = 0; 562 563 /* Init first segment length for backout at failure */ 564 outs->dma_length = 0; 565 566 max_seg_size = dma_get_max_seg_size(dev); 567 seg_boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1, 568 IO_PAGE_SIZE) >> IO_PAGE_SHIFT; 569 base_shift = iommu->page_table_map_base >> IO_PAGE_SHIFT; 570 for_each_sg(sglist, s, nelems, i) { 571 unsigned long paddr, npages, entry, out_entry = 0, slen; 572 iopte_t *base; 573 574 slen = s->length; 575 /* Sanity check */ 576 if (slen == 0) { 577 dma_next = 0; 578 continue; 579 } 580 /* Allocate iommu entries for that segment */ 581 paddr = (unsigned long) SG_ENT_PHYS_ADDRESS(s); 582 npages = iommu_num_pages(paddr, slen, IO_PAGE_SIZE); 583 entry = iommu_range_alloc(dev, iommu, npages, &handle); 584 585 /* Handle failure */ 586 if (unlikely(entry == DMA_ERROR_CODE)) { 587 if (printk_ratelimit()) 588 printk(KERN_INFO "iommu_alloc failed, iommu %p paddr %lx" 589 " npages %lx\n", iommu, paddr, npages); 590 goto iommu_map_failed; 591 } 592 593 base = iommu->page_table + entry; 594 595 /* Convert entry to a dma_addr_t */ 596 dma_addr = iommu->page_table_map_base + 597 (entry << IO_PAGE_SHIFT); 598 dma_addr |= (s->offset & ~IO_PAGE_MASK); 599 600 /* Insert into HW table */ 601 paddr &= IO_PAGE_MASK; 602 while (npages--) { 603 iopte_val(*base) = prot | paddr; 604 base++; 605 paddr += IO_PAGE_SIZE; 606 } 607 608 /* If we are in an open segment, try merging */ 609 if (segstart != s) { 610 /* We cannot merge if: 611 * - allocated dma_addr isn't contiguous to previous allocation 612 */ 613 if ((dma_addr != dma_next) || 614 (outs->dma_length + s->length > max_seg_size) || 615 (is_span_boundary(out_entry, base_shift, 616 seg_boundary_size, outs, s))) { 617 /* Can't merge: create a new segment */ 618 segstart = s; 619 outcount++; 620 outs = sg_next(outs); 621 } else { 622 outs->dma_length += s->length; 623 } 624 } 625 626 if (segstart == s) { 627 /* This is a new segment, fill entries */ 628 outs->dma_address = dma_addr; 629 outs->dma_length = slen; 630 out_entry = entry; 631 } 632 633 /* Calculate next page pointer for contiguous check */ 634 dma_next = dma_addr + slen; 635 } 636 637 spin_unlock_irqrestore(&iommu->lock, flags); 638 639 if (outcount < incount) { 640 outs = sg_next(outs); 641 outs->dma_address = DMA_ERROR_CODE; 642 outs->dma_length = 0; 643 } 644 645 return outcount; 646 647 iommu_map_failed: 648 for_each_sg(sglist, s, nelems, i) { 649 if (s->dma_length != 0) { 650 unsigned long vaddr, npages, entry, j; 651 iopte_t *base; 652 653 vaddr = s->dma_address & IO_PAGE_MASK; 654 npages = iommu_num_pages(s->dma_address, s->dma_length, 655 IO_PAGE_SIZE); 656 iommu_range_free(iommu, vaddr, npages); 657 658 entry = (vaddr - iommu->page_table_map_base) 659 >> IO_PAGE_SHIFT; 660 base = iommu->page_table + entry; 661 662 for (j = 0; j < npages; j++) 663 iopte_make_dummy(iommu, base + j); 664 665 s->dma_address = DMA_ERROR_CODE; 666 s->dma_length = 0; 667 } 668 if (s == outs) 669 break; 670 } 671 spin_unlock_irqrestore(&iommu->lock, flags); 672 673 return 0; 674 } 675 676 /* If contexts are being used, they are the same in all of the mappings 677 * we make for a particular SG. 678 */ 679 static unsigned long fetch_sg_ctx(struct iommu *iommu, struct scatterlist *sg) 680 { 681 unsigned long ctx = 0; 682 683 if (iommu->iommu_ctxflush) { 684 iopte_t *base; 685 u32 bus_addr; 686 687 bus_addr = sg->dma_address & IO_PAGE_MASK; 688 base = iommu->page_table + 689 ((bus_addr - iommu->page_table_map_base) >> IO_PAGE_SHIFT); 690 691 ctx = (iopte_val(*base) & IOPTE_CONTEXT) >> 47UL; 692 } 693 return ctx; 694 } 695 696 static void dma_4u_unmap_sg(struct device *dev, struct scatterlist *sglist, 697 int nelems, enum dma_data_direction direction, 698 struct dma_attrs *attrs) 699 { 700 unsigned long flags, ctx; 701 struct scatterlist *sg; 702 struct strbuf *strbuf; 703 struct iommu *iommu; 704 705 BUG_ON(direction == DMA_NONE); 706 707 iommu = dev->archdata.iommu; 708 strbuf = dev->archdata.stc; 709 710 ctx = fetch_sg_ctx(iommu, sglist); 711 712 spin_lock_irqsave(&iommu->lock, flags); 713 714 sg = sglist; 715 while (nelems--) { 716 dma_addr_t dma_handle = sg->dma_address; 717 unsigned int len = sg->dma_length; 718 unsigned long npages, entry; 719 iopte_t *base; 720 int i; 721 722 if (!len) 723 break; 724 npages = iommu_num_pages(dma_handle, len, IO_PAGE_SIZE); 725 iommu_range_free(iommu, dma_handle, npages); 726 727 entry = ((dma_handle - iommu->page_table_map_base) 728 >> IO_PAGE_SHIFT); 729 base = iommu->page_table + entry; 730 731 dma_handle &= IO_PAGE_MASK; 732 if (strbuf->strbuf_enabled) 733 strbuf_flush(strbuf, iommu, dma_handle, ctx, 734 npages, direction); 735 736 for (i = 0; i < npages; i++) 737 iopte_make_dummy(iommu, base + i); 738 739 sg = sg_next(sg); 740 } 741 742 iommu_free_ctx(iommu, ctx); 743 744 spin_unlock_irqrestore(&iommu->lock, flags); 745 } 746 747 static void dma_4u_sync_single_for_cpu(struct device *dev, 748 dma_addr_t bus_addr, size_t sz, 749 enum dma_data_direction direction) 750 { 751 struct iommu *iommu; 752 struct strbuf *strbuf; 753 unsigned long flags, ctx, npages; 754 755 iommu = dev->archdata.iommu; 756 strbuf = dev->archdata.stc; 757 758 if (!strbuf->strbuf_enabled) 759 return; 760 761 spin_lock_irqsave(&iommu->lock, flags); 762 763 npages = IO_PAGE_ALIGN(bus_addr + sz) - (bus_addr & IO_PAGE_MASK); 764 npages >>= IO_PAGE_SHIFT; 765 bus_addr &= IO_PAGE_MASK; 766 767 /* Step 1: Record the context, if any. */ 768 ctx = 0; 769 if (iommu->iommu_ctxflush && 770 strbuf->strbuf_ctxflush) { 771 iopte_t *iopte; 772 773 iopte = iommu->page_table + 774 ((bus_addr - iommu->page_table_map_base)>>IO_PAGE_SHIFT); 775 ctx = (iopte_val(*iopte) & IOPTE_CONTEXT) >> 47UL; 776 } 777 778 /* Step 2: Kick data out of streaming buffers. */ 779 strbuf_flush(strbuf, iommu, bus_addr, ctx, npages, direction); 780 781 spin_unlock_irqrestore(&iommu->lock, flags); 782 } 783 784 static void dma_4u_sync_sg_for_cpu(struct device *dev, 785 struct scatterlist *sglist, int nelems, 786 enum dma_data_direction direction) 787 { 788 struct iommu *iommu; 789 struct strbuf *strbuf; 790 unsigned long flags, ctx, npages, i; 791 struct scatterlist *sg, *sgprv; 792 u32 bus_addr; 793 794 iommu = dev->archdata.iommu; 795 strbuf = dev->archdata.stc; 796 797 if (!strbuf->strbuf_enabled) 798 return; 799 800 spin_lock_irqsave(&iommu->lock, flags); 801 802 /* Step 1: Record the context, if any. */ 803 ctx = 0; 804 if (iommu->iommu_ctxflush && 805 strbuf->strbuf_ctxflush) { 806 iopte_t *iopte; 807 808 iopte = iommu->page_table + 809 ((sglist[0].dma_address - iommu->page_table_map_base) >> IO_PAGE_SHIFT); 810 ctx = (iopte_val(*iopte) & IOPTE_CONTEXT) >> 47UL; 811 } 812 813 /* Step 2: Kick data out of streaming buffers. */ 814 bus_addr = sglist[0].dma_address & IO_PAGE_MASK; 815 sgprv = NULL; 816 for_each_sg(sglist, sg, nelems, i) { 817 if (sg->dma_length == 0) 818 break; 819 sgprv = sg; 820 } 821 822 npages = (IO_PAGE_ALIGN(sgprv->dma_address + sgprv->dma_length) 823 - bus_addr) >> IO_PAGE_SHIFT; 824 strbuf_flush(strbuf, iommu, bus_addr, ctx, npages, direction); 825 826 spin_unlock_irqrestore(&iommu->lock, flags); 827 } 828 829 static struct dma_map_ops sun4u_dma_ops = { 830 .alloc = dma_4u_alloc_coherent, 831 .free = dma_4u_free_coherent, 832 .map_page = dma_4u_map_page, 833 .unmap_page = dma_4u_unmap_page, 834 .map_sg = dma_4u_map_sg, 835 .unmap_sg = dma_4u_unmap_sg, 836 .sync_single_for_cpu = dma_4u_sync_single_for_cpu, 837 .sync_sg_for_cpu = dma_4u_sync_sg_for_cpu, 838 }; 839 840 struct dma_map_ops *dma_ops = &sun4u_dma_ops; 841 EXPORT_SYMBOL(dma_ops); 842 843 extern int pci64_dma_supported(struct pci_dev *pdev, u64 device_mask); 844 845 int dma_supported(struct device *dev, u64 device_mask) 846 { 847 struct iommu *iommu = dev->archdata.iommu; 848 u64 dma_addr_mask = iommu->dma_addr_mask; 849 850 if (device_mask >= (1UL << 32UL)) 851 return 0; 852 853 if ((device_mask & dma_addr_mask) == dma_addr_mask) 854 return 1; 855 856 #ifdef CONFIG_PCI 857 if (dev->bus == &pci_bus_type) 858 return pci64_dma_supported(to_pci_dev(dev), device_mask); 859 #endif 860 861 return 0; 862 } 863 EXPORT_SYMBOL(dma_supported); 864