1 // SPDX-License-Identifier: GPL-2.0 2 /* iommu.c: Generic sparc64 IOMMU support. 3 * 4 * Copyright (C) 1999, 2007, 2008 David S. Miller (davem@davemloft.net) 5 * Copyright (C) 1999, 2000 Jakub Jelinek (jakub@redhat.com) 6 */ 7 8 #include <linux/kernel.h> 9 #include <linux/export.h> 10 #include <linux/slab.h> 11 #include <linux/delay.h> 12 #include <linux/device.h> 13 #include <linux/dma-mapping.h> 14 #include <linux/errno.h> 15 #include <linux/iommu-helper.h> 16 #include <linux/bitmap.h> 17 #include <asm/iommu-common.h> 18 19 #ifdef CONFIG_PCI 20 #include <linux/pci.h> 21 #endif 22 23 #include <asm/iommu.h> 24 25 #include "iommu_common.h" 26 #include "kernel.h" 27 28 #define STC_CTXMATCH_ADDR(STC, CTX) \ 29 ((STC)->strbuf_ctxmatch_base + ((CTX) << 3)) 30 #define STC_FLUSHFLAG_INIT(STC) \ 31 (*((STC)->strbuf_flushflag) = 0UL) 32 #define STC_FLUSHFLAG_SET(STC) \ 33 (*((STC)->strbuf_flushflag) != 0UL) 34 35 #define iommu_read(__reg) \ 36 ({ u64 __ret; \ 37 __asm__ __volatile__("ldxa [%1] %2, %0" \ 38 : "=r" (__ret) \ 39 : "r" (__reg), "i" (ASI_PHYS_BYPASS_EC_E) \ 40 : "memory"); \ 41 __ret; \ 42 }) 43 #define iommu_write(__reg, __val) \ 44 __asm__ __volatile__("stxa %0, [%1] %2" \ 45 : /* no outputs */ \ 46 : "r" (__val), "r" (__reg), \ 47 "i" (ASI_PHYS_BYPASS_EC_E)) 48 49 /* Must be invoked under the IOMMU lock. */ 50 static void iommu_flushall(struct iommu_map_table *iommu_map_table) 51 { 52 struct iommu *iommu = container_of(iommu_map_table, struct iommu, tbl); 53 if (iommu->iommu_flushinv) { 54 iommu_write(iommu->iommu_flushinv, ~(u64)0); 55 } else { 56 unsigned long tag; 57 int entry; 58 59 tag = iommu->iommu_tags; 60 for (entry = 0; entry < 16; entry++) { 61 iommu_write(tag, 0); 62 tag += 8; 63 } 64 65 /* Ensure completion of previous PIO writes. */ 66 (void) iommu_read(iommu->write_complete_reg); 67 } 68 } 69 70 #define IOPTE_CONSISTENT(CTX) \ 71 (IOPTE_VALID | IOPTE_CACHE | \ 72 (((CTX) << 47) & IOPTE_CONTEXT)) 73 74 #define IOPTE_STREAMING(CTX) \ 75 (IOPTE_CONSISTENT(CTX) | IOPTE_STBUF) 76 77 /* Existing mappings are never marked invalid, instead they 78 * are pointed to a dummy page. 79 */ 80 #define IOPTE_IS_DUMMY(iommu, iopte) \ 81 ((iopte_val(*iopte) & IOPTE_PAGE) == (iommu)->dummy_page_pa) 82 83 static inline void iopte_make_dummy(struct iommu *iommu, iopte_t *iopte) 84 { 85 unsigned long val = iopte_val(*iopte); 86 87 val &= ~IOPTE_PAGE; 88 val |= iommu->dummy_page_pa; 89 90 iopte_val(*iopte) = val; 91 } 92 93 int iommu_table_init(struct iommu *iommu, int tsbsize, 94 u32 dma_offset, u32 dma_addr_mask, 95 int numa_node) 96 { 97 unsigned long i, order, sz, num_tsb_entries; 98 struct page *page; 99 100 num_tsb_entries = tsbsize / sizeof(iopte_t); 101 102 /* Setup initial software IOMMU state. */ 103 spin_lock_init(&iommu->lock); 104 iommu->ctx_lowest_free = 1; 105 iommu->tbl.table_map_base = dma_offset; 106 iommu->dma_addr_mask = dma_addr_mask; 107 108 /* Allocate and initialize the free area map. */ 109 sz = num_tsb_entries / 8; 110 sz = (sz + 7UL) & ~7UL; 111 iommu->tbl.map = kzalloc_node(sz, GFP_KERNEL, numa_node); 112 if (!iommu->tbl.map) 113 return -ENOMEM; 114 115 iommu_tbl_pool_init(&iommu->tbl, num_tsb_entries, IO_PAGE_SHIFT, 116 (tlb_type != hypervisor ? iommu_flushall : NULL), 117 false, 1, false); 118 119 /* Allocate and initialize the dummy page which we 120 * set inactive IO PTEs to point to. 121 */ 122 page = alloc_pages_node(numa_node, GFP_KERNEL, 0); 123 if (!page) { 124 printk(KERN_ERR "IOMMU: Error, gfp(dummy_page) failed.\n"); 125 goto out_free_map; 126 } 127 iommu->dummy_page = (unsigned long) page_address(page); 128 memset((void *)iommu->dummy_page, 0, PAGE_SIZE); 129 iommu->dummy_page_pa = (unsigned long) __pa(iommu->dummy_page); 130 131 /* Now allocate and setup the IOMMU page table itself. */ 132 order = get_order(tsbsize); 133 page = alloc_pages_node(numa_node, GFP_KERNEL, order); 134 if (!page) { 135 printk(KERN_ERR "IOMMU: Error, gfp(tsb) failed.\n"); 136 goto out_free_dummy_page; 137 } 138 iommu->page_table = (iopte_t *)page_address(page); 139 140 for (i = 0; i < num_tsb_entries; i++) 141 iopte_make_dummy(iommu, &iommu->page_table[i]); 142 143 return 0; 144 145 out_free_dummy_page: 146 free_page(iommu->dummy_page); 147 iommu->dummy_page = 0UL; 148 149 out_free_map: 150 kfree(iommu->tbl.map); 151 iommu->tbl.map = NULL; 152 153 return -ENOMEM; 154 } 155 156 static inline iopte_t *alloc_npages(struct device *dev, 157 struct iommu *iommu, 158 unsigned long npages) 159 { 160 unsigned long entry; 161 162 entry = iommu_tbl_range_alloc(dev, &iommu->tbl, npages, NULL, 163 (unsigned long)(-1), 0); 164 if (unlikely(entry == IOMMU_ERROR_CODE)) 165 return NULL; 166 167 return iommu->page_table + entry; 168 } 169 170 static int iommu_alloc_ctx(struct iommu *iommu) 171 { 172 int lowest = iommu->ctx_lowest_free; 173 int n = find_next_zero_bit(iommu->ctx_bitmap, IOMMU_NUM_CTXS, lowest); 174 175 if (unlikely(n == IOMMU_NUM_CTXS)) { 176 n = find_next_zero_bit(iommu->ctx_bitmap, lowest, 1); 177 if (unlikely(n == lowest)) { 178 printk(KERN_WARNING "IOMMU: Ran out of contexts.\n"); 179 n = 0; 180 } 181 } 182 if (n) 183 __set_bit(n, iommu->ctx_bitmap); 184 185 return n; 186 } 187 188 static inline void iommu_free_ctx(struct iommu *iommu, int ctx) 189 { 190 if (likely(ctx)) { 191 __clear_bit(ctx, iommu->ctx_bitmap); 192 if (ctx < iommu->ctx_lowest_free) 193 iommu->ctx_lowest_free = ctx; 194 } 195 } 196 197 static void *dma_4u_alloc_coherent(struct device *dev, size_t size, 198 dma_addr_t *dma_addrp, gfp_t gfp, 199 unsigned long attrs) 200 { 201 unsigned long order, first_page; 202 struct iommu *iommu; 203 struct page *page; 204 int npages, nid; 205 iopte_t *iopte; 206 void *ret; 207 208 size = IO_PAGE_ALIGN(size); 209 order = get_order(size); 210 if (order >= 10) 211 return NULL; 212 213 nid = dev->archdata.numa_node; 214 page = alloc_pages_node(nid, gfp, order); 215 if (unlikely(!page)) 216 return NULL; 217 218 first_page = (unsigned long) page_address(page); 219 memset((char *)first_page, 0, PAGE_SIZE << order); 220 221 iommu = dev->archdata.iommu; 222 223 iopte = alloc_npages(dev, iommu, size >> IO_PAGE_SHIFT); 224 225 if (unlikely(iopte == NULL)) { 226 free_pages(first_page, order); 227 return NULL; 228 } 229 230 *dma_addrp = (iommu->tbl.table_map_base + 231 ((iopte - iommu->page_table) << IO_PAGE_SHIFT)); 232 ret = (void *) first_page; 233 npages = size >> IO_PAGE_SHIFT; 234 first_page = __pa(first_page); 235 while (npages--) { 236 iopte_val(*iopte) = (IOPTE_CONSISTENT(0UL) | 237 IOPTE_WRITE | 238 (first_page & IOPTE_PAGE)); 239 iopte++; 240 first_page += IO_PAGE_SIZE; 241 } 242 243 return ret; 244 } 245 246 static void dma_4u_free_coherent(struct device *dev, size_t size, 247 void *cpu, dma_addr_t dvma, 248 unsigned long attrs) 249 { 250 struct iommu *iommu; 251 unsigned long order, npages; 252 253 npages = IO_PAGE_ALIGN(size) >> IO_PAGE_SHIFT; 254 iommu = dev->archdata.iommu; 255 256 iommu_tbl_range_free(&iommu->tbl, dvma, npages, IOMMU_ERROR_CODE); 257 258 order = get_order(size); 259 if (order < 10) 260 free_pages((unsigned long)cpu, order); 261 } 262 263 static dma_addr_t dma_4u_map_page(struct device *dev, struct page *page, 264 unsigned long offset, size_t sz, 265 enum dma_data_direction direction, 266 unsigned long attrs) 267 { 268 struct iommu *iommu; 269 struct strbuf *strbuf; 270 iopte_t *base; 271 unsigned long flags, npages, oaddr; 272 unsigned long i, base_paddr, ctx; 273 u32 bus_addr, ret; 274 unsigned long iopte_protection; 275 276 iommu = dev->archdata.iommu; 277 strbuf = dev->archdata.stc; 278 279 if (unlikely(direction == DMA_NONE)) 280 goto bad_no_ctx; 281 282 oaddr = (unsigned long)(page_address(page) + offset); 283 npages = IO_PAGE_ALIGN(oaddr + sz) - (oaddr & IO_PAGE_MASK); 284 npages >>= IO_PAGE_SHIFT; 285 286 base = alloc_npages(dev, iommu, npages); 287 spin_lock_irqsave(&iommu->lock, flags); 288 ctx = 0; 289 if (iommu->iommu_ctxflush) 290 ctx = iommu_alloc_ctx(iommu); 291 spin_unlock_irqrestore(&iommu->lock, flags); 292 293 if (unlikely(!base)) 294 goto bad; 295 296 bus_addr = (iommu->tbl.table_map_base + 297 ((base - iommu->page_table) << IO_PAGE_SHIFT)); 298 ret = bus_addr | (oaddr & ~IO_PAGE_MASK); 299 base_paddr = __pa(oaddr & IO_PAGE_MASK); 300 if (strbuf->strbuf_enabled) 301 iopte_protection = IOPTE_STREAMING(ctx); 302 else 303 iopte_protection = IOPTE_CONSISTENT(ctx); 304 if (direction != DMA_TO_DEVICE) 305 iopte_protection |= IOPTE_WRITE; 306 307 for (i = 0; i < npages; i++, base++, base_paddr += IO_PAGE_SIZE) 308 iopte_val(*base) = iopte_protection | base_paddr; 309 310 return ret; 311 312 bad: 313 iommu_free_ctx(iommu, ctx); 314 bad_no_ctx: 315 if (printk_ratelimit()) 316 WARN_ON(1); 317 return DMA_MAPPING_ERROR; 318 } 319 320 static void strbuf_flush(struct strbuf *strbuf, struct iommu *iommu, 321 u32 vaddr, unsigned long ctx, unsigned long npages, 322 enum dma_data_direction direction) 323 { 324 int limit; 325 326 if (strbuf->strbuf_ctxflush && 327 iommu->iommu_ctxflush) { 328 unsigned long matchreg, flushreg; 329 u64 val; 330 331 flushreg = strbuf->strbuf_ctxflush; 332 matchreg = STC_CTXMATCH_ADDR(strbuf, ctx); 333 334 iommu_write(flushreg, ctx); 335 val = iommu_read(matchreg); 336 val &= 0xffff; 337 if (!val) 338 goto do_flush_sync; 339 340 while (val) { 341 if (val & 0x1) 342 iommu_write(flushreg, ctx); 343 val >>= 1; 344 } 345 val = iommu_read(matchreg); 346 if (unlikely(val)) { 347 printk(KERN_WARNING "strbuf_flush: ctx flush " 348 "timeout matchreg[%llx] ctx[%lx]\n", 349 val, ctx); 350 goto do_page_flush; 351 } 352 } else { 353 unsigned long i; 354 355 do_page_flush: 356 for (i = 0; i < npages; i++, vaddr += IO_PAGE_SIZE) 357 iommu_write(strbuf->strbuf_pflush, vaddr); 358 } 359 360 do_flush_sync: 361 /* If the device could not have possibly put dirty data into 362 * the streaming cache, no flush-flag synchronization needs 363 * to be performed. 364 */ 365 if (direction == DMA_TO_DEVICE) 366 return; 367 368 STC_FLUSHFLAG_INIT(strbuf); 369 iommu_write(strbuf->strbuf_fsync, strbuf->strbuf_flushflag_pa); 370 (void) iommu_read(iommu->write_complete_reg); 371 372 limit = 100000; 373 while (!STC_FLUSHFLAG_SET(strbuf)) { 374 limit--; 375 if (!limit) 376 break; 377 udelay(1); 378 rmb(); 379 } 380 if (!limit) 381 printk(KERN_WARNING "strbuf_flush: flushflag timeout " 382 "vaddr[%08x] ctx[%lx] npages[%ld]\n", 383 vaddr, ctx, npages); 384 } 385 386 static void dma_4u_unmap_page(struct device *dev, dma_addr_t bus_addr, 387 size_t sz, enum dma_data_direction direction, 388 unsigned long attrs) 389 { 390 struct iommu *iommu; 391 struct strbuf *strbuf; 392 iopte_t *base; 393 unsigned long flags, npages, ctx, i; 394 395 if (unlikely(direction == DMA_NONE)) { 396 if (printk_ratelimit()) 397 WARN_ON(1); 398 return; 399 } 400 401 iommu = dev->archdata.iommu; 402 strbuf = dev->archdata.stc; 403 404 npages = IO_PAGE_ALIGN(bus_addr + sz) - (bus_addr & IO_PAGE_MASK); 405 npages >>= IO_PAGE_SHIFT; 406 base = iommu->page_table + 407 ((bus_addr - iommu->tbl.table_map_base) >> IO_PAGE_SHIFT); 408 bus_addr &= IO_PAGE_MASK; 409 410 spin_lock_irqsave(&iommu->lock, flags); 411 412 /* Record the context, if any. */ 413 ctx = 0; 414 if (iommu->iommu_ctxflush) 415 ctx = (iopte_val(*base) & IOPTE_CONTEXT) >> 47UL; 416 417 /* Step 1: Kick data out of streaming buffers if necessary. */ 418 if (strbuf->strbuf_enabled && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) 419 strbuf_flush(strbuf, iommu, bus_addr, ctx, 420 npages, direction); 421 422 /* Step 2: Clear out TSB entries. */ 423 for (i = 0; i < npages; i++) 424 iopte_make_dummy(iommu, base + i); 425 426 iommu_free_ctx(iommu, ctx); 427 spin_unlock_irqrestore(&iommu->lock, flags); 428 429 iommu_tbl_range_free(&iommu->tbl, bus_addr, npages, IOMMU_ERROR_CODE); 430 } 431 432 static int dma_4u_map_sg(struct device *dev, struct scatterlist *sglist, 433 int nelems, enum dma_data_direction direction, 434 unsigned long attrs) 435 { 436 struct scatterlist *s, *outs, *segstart; 437 unsigned long flags, handle, prot, ctx; 438 dma_addr_t dma_next = 0, dma_addr; 439 unsigned int max_seg_size; 440 unsigned long seg_boundary_size; 441 int outcount, incount, i; 442 struct strbuf *strbuf; 443 struct iommu *iommu; 444 unsigned long base_shift; 445 446 BUG_ON(direction == DMA_NONE); 447 448 iommu = dev->archdata.iommu; 449 strbuf = dev->archdata.stc; 450 if (nelems == 0 || !iommu) 451 return 0; 452 453 spin_lock_irqsave(&iommu->lock, flags); 454 455 ctx = 0; 456 if (iommu->iommu_ctxflush) 457 ctx = iommu_alloc_ctx(iommu); 458 459 if (strbuf->strbuf_enabled) 460 prot = IOPTE_STREAMING(ctx); 461 else 462 prot = IOPTE_CONSISTENT(ctx); 463 if (direction != DMA_TO_DEVICE) 464 prot |= IOPTE_WRITE; 465 466 outs = s = segstart = &sglist[0]; 467 outcount = 1; 468 incount = nelems; 469 handle = 0; 470 471 /* Init first segment length for backout at failure */ 472 outs->dma_length = 0; 473 474 max_seg_size = dma_get_max_seg_size(dev); 475 seg_boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1, 476 IO_PAGE_SIZE) >> IO_PAGE_SHIFT; 477 base_shift = iommu->tbl.table_map_base >> IO_PAGE_SHIFT; 478 for_each_sg(sglist, s, nelems, i) { 479 unsigned long paddr, npages, entry, out_entry = 0, slen; 480 iopte_t *base; 481 482 slen = s->length; 483 /* Sanity check */ 484 if (slen == 0) { 485 dma_next = 0; 486 continue; 487 } 488 /* Allocate iommu entries for that segment */ 489 paddr = (unsigned long) SG_ENT_PHYS_ADDRESS(s); 490 npages = iommu_num_pages(paddr, slen, IO_PAGE_SIZE); 491 entry = iommu_tbl_range_alloc(dev, &iommu->tbl, npages, 492 &handle, (unsigned long)(-1), 0); 493 494 /* Handle failure */ 495 if (unlikely(entry == IOMMU_ERROR_CODE)) { 496 if (printk_ratelimit()) 497 printk(KERN_INFO "iommu_alloc failed, iommu %p paddr %lx" 498 " npages %lx\n", iommu, paddr, npages); 499 goto iommu_map_failed; 500 } 501 502 base = iommu->page_table + entry; 503 504 /* Convert entry to a dma_addr_t */ 505 dma_addr = iommu->tbl.table_map_base + 506 (entry << IO_PAGE_SHIFT); 507 dma_addr |= (s->offset & ~IO_PAGE_MASK); 508 509 /* Insert into HW table */ 510 paddr &= IO_PAGE_MASK; 511 while (npages--) { 512 iopte_val(*base) = prot | paddr; 513 base++; 514 paddr += IO_PAGE_SIZE; 515 } 516 517 /* If we are in an open segment, try merging */ 518 if (segstart != s) { 519 /* We cannot merge if: 520 * - allocated dma_addr isn't contiguous to previous allocation 521 */ 522 if ((dma_addr != dma_next) || 523 (outs->dma_length + s->length > max_seg_size) || 524 (is_span_boundary(out_entry, base_shift, 525 seg_boundary_size, outs, s))) { 526 /* Can't merge: create a new segment */ 527 segstart = s; 528 outcount++; 529 outs = sg_next(outs); 530 } else { 531 outs->dma_length += s->length; 532 } 533 } 534 535 if (segstart == s) { 536 /* This is a new segment, fill entries */ 537 outs->dma_address = dma_addr; 538 outs->dma_length = slen; 539 out_entry = entry; 540 } 541 542 /* Calculate next page pointer for contiguous check */ 543 dma_next = dma_addr + slen; 544 } 545 546 spin_unlock_irqrestore(&iommu->lock, flags); 547 548 if (outcount < incount) { 549 outs = sg_next(outs); 550 outs->dma_address = DMA_MAPPING_ERROR; 551 outs->dma_length = 0; 552 } 553 554 return outcount; 555 556 iommu_map_failed: 557 for_each_sg(sglist, s, nelems, i) { 558 if (s->dma_length != 0) { 559 unsigned long vaddr, npages, entry, j; 560 iopte_t *base; 561 562 vaddr = s->dma_address & IO_PAGE_MASK; 563 npages = iommu_num_pages(s->dma_address, s->dma_length, 564 IO_PAGE_SIZE); 565 566 entry = (vaddr - iommu->tbl.table_map_base) 567 >> IO_PAGE_SHIFT; 568 base = iommu->page_table + entry; 569 570 for (j = 0; j < npages; j++) 571 iopte_make_dummy(iommu, base + j); 572 573 iommu_tbl_range_free(&iommu->tbl, vaddr, npages, 574 IOMMU_ERROR_CODE); 575 576 s->dma_address = DMA_MAPPING_ERROR; 577 s->dma_length = 0; 578 } 579 if (s == outs) 580 break; 581 } 582 spin_unlock_irqrestore(&iommu->lock, flags); 583 584 return 0; 585 } 586 587 /* If contexts are being used, they are the same in all of the mappings 588 * we make for a particular SG. 589 */ 590 static unsigned long fetch_sg_ctx(struct iommu *iommu, struct scatterlist *sg) 591 { 592 unsigned long ctx = 0; 593 594 if (iommu->iommu_ctxflush) { 595 iopte_t *base; 596 u32 bus_addr; 597 struct iommu_map_table *tbl = &iommu->tbl; 598 599 bus_addr = sg->dma_address & IO_PAGE_MASK; 600 base = iommu->page_table + 601 ((bus_addr - tbl->table_map_base) >> IO_PAGE_SHIFT); 602 603 ctx = (iopte_val(*base) & IOPTE_CONTEXT) >> 47UL; 604 } 605 return ctx; 606 } 607 608 static void dma_4u_unmap_sg(struct device *dev, struct scatterlist *sglist, 609 int nelems, enum dma_data_direction direction, 610 unsigned long attrs) 611 { 612 unsigned long flags, ctx; 613 struct scatterlist *sg; 614 struct strbuf *strbuf; 615 struct iommu *iommu; 616 617 BUG_ON(direction == DMA_NONE); 618 619 iommu = dev->archdata.iommu; 620 strbuf = dev->archdata.stc; 621 622 ctx = fetch_sg_ctx(iommu, sglist); 623 624 spin_lock_irqsave(&iommu->lock, flags); 625 626 sg = sglist; 627 while (nelems--) { 628 dma_addr_t dma_handle = sg->dma_address; 629 unsigned int len = sg->dma_length; 630 unsigned long npages, entry; 631 iopte_t *base; 632 int i; 633 634 if (!len) 635 break; 636 npages = iommu_num_pages(dma_handle, len, IO_PAGE_SIZE); 637 638 entry = ((dma_handle - iommu->tbl.table_map_base) 639 >> IO_PAGE_SHIFT); 640 base = iommu->page_table + entry; 641 642 dma_handle &= IO_PAGE_MASK; 643 if (strbuf->strbuf_enabled && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) 644 strbuf_flush(strbuf, iommu, dma_handle, ctx, 645 npages, direction); 646 647 for (i = 0; i < npages; i++) 648 iopte_make_dummy(iommu, base + i); 649 650 iommu_tbl_range_free(&iommu->tbl, dma_handle, npages, 651 IOMMU_ERROR_CODE); 652 sg = sg_next(sg); 653 } 654 655 iommu_free_ctx(iommu, ctx); 656 657 spin_unlock_irqrestore(&iommu->lock, flags); 658 } 659 660 static void dma_4u_sync_single_for_cpu(struct device *dev, 661 dma_addr_t bus_addr, size_t sz, 662 enum dma_data_direction direction) 663 { 664 struct iommu *iommu; 665 struct strbuf *strbuf; 666 unsigned long flags, ctx, npages; 667 668 iommu = dev->archdata.iommu; 669 strbuf = dev->archdata.stc; 670 671 if (!strbuf->strbuf_enabled) 672 return; 673 674 spin_lock_irqsave(&iommu->lock, flags); 675 676 npages = IO_PAGE_ALIGN(bus_addr + sz) - (bus_addr & IO_PAGE_MASK); 677 npages >>= IO_PAGE_SHIFT; 678 bus_addr &= IO_PAGE_MASK; 679 680 /* Step 1: Record the context, if any. */ 681 ctx = 0; 682 if (iommu->iommu_ctxflush && 683 strbuf->strbuf_ctxflush) { 684 iopte_t *iopte; 685 struct iommu_map_table *tbl = &iommu->tbl; 686 687 iopte = iommu->page_table + 688 ((bus_addr - tbl->table_map_base)>>IO_PAGE_SHIFT); 689 ctx = (iopte_val(*iopte) & IOPTE_CONTEXT) >> 47UL; 690 } 691 692 /* Step 2: Kick data out of streaming buffers. */ 693 strbuf_flush(strbuf, iommu, bus_addr, ctx, npages, direction); 694 695 spin_unlock_irqrestore(&iommu->lock, flags); 696 } 697 698 static void dma_4u_sync_sg_for_cpu(struct device *dev, 699 struct scatterlist *sglist, int nelems, 700 enum dma_data_direction direction) 701 { 702 struct iommu *iommu; 703 struct strbuf *strbuf; 704 unsigned long flags, ctx, npages, i; 705 struct scatterlist *sg, *sgprv; 706 u32 bus_addr; 707 708 iommu = dev->archdata.iommu; 709 strbuf = dev->archdata.stc; 710 711 if (!strbuf->strbuf_enabled) 712 return; 713 714 spin_lock_irqsave(&iommu->lock, flags); 715 716 /* Step 1: Record the context, if any. */ 717 ctx = 0; 718 if (iommu->iommu_ctxflush && 719 strbuf->strbuf_ctxflush) { 720 iopte_t *iopte; 721 struct iommu_map_table *tbl = &iommu->tbl; 722 723 iopte = iommu->page_table + ((sglist[0].dma_address - 724 tbl->table_map_base) >> IO_PAGE_SHIFT); 725 ctx = (iopte_val(*iopte) & IOPTE_CONTEXT) >> 47UL; 726 } 727 728 /* Step 2: Kick data out of streaming buffers. */ 729 bus_addr = sglist[0].dma_address & IO_PAGE_MASK; 730 sgprv = NULL; 731 for_each_sg(sglist, sg, nelems, i) { 732 if (sg->dma_length == 0) 733 break; 734 sgprv = sg; 735 } 736 737 npages = (IO_PAGE_ALIGN(sgprv->dma_address + sgprv->dma_length) 738 - bus_addr) >> IO_PAGE_SHIFT; 739 strbuf_flush(strbuf, iommu, bus_addr, ctx, npages, direction); 740 741 spin_unlock_irqrestore(&iommu->lock, flags); 742 } 743 744 static int dma_4u_supported(struct device *dev, u64 device_mask) 745 { 746 struct iommu *iommu = dev->archdata.iommu; 747 748 if (device_mask > DMA_BIT_MASK(32)) 749 return 0; 750 if ((device_mask & iommu->dma_addr_mask) == iommu->dma_addr_mask) 751 return 1; 752 #ifdef CONFIG_PCI 753 if (dev_is_pci(dev)) 754 return pci64_dma_supported(to_pci_dev(dev), device_mask); 755 #endif 756 return 0; 757 } 758 759 static const struct dma_map_ops sun4u_dma_ops = { 760 .alloc = dma_4u_alloc_coherent, 761 .free = dma_4u_free_coherent, 762 .map_page = dma_4u_map_page, 763 .unmap_page = dma_4u_unmap_page, 764 .map_sg = dma_4u_map_sg, 765 .unmap_sg = dma_4u_unmap_sg, 766 .sync_single_for_cpu = dma_4u_sync_single_for_cpu, 767 .sync_sg_for_cpu = dma_4u_sync_sg_for_cpu, 768 .dma_supported = dma_4u_supported, 769 }; 770 771 const struct dma_map_ops *dma_ops = &sun4u_dma_ops; 772 EXPORT_SYMBOL(dma_ops); 773