1 /* 2 ** PARISC 1.1 Dynamic DMA mapping support. 3 ** This implementation is for PA-RISC platforms that do not support 4 ** I/O TLBs (aka DMA address translation hardware). 5 ** See Documentation/PCI/PCI-DMA-mapping.txt for interface definitions. 6 ** 7 ** (c) Copyright 1999,2000 Hewlett-Packard Company 8 ** (c) Copyright 2000 Grant Grundler 9 ** (c) Copyright 2000 Philipp Rumpf <prumpf@tux.org> 10 ** (c) Copyright 2000 John Marvin 11 ** 12 ** "leveraged" from 2.3.47: arch/ia64/kernel/pci-dma.c. 13 ** (I assume it's from David Mosberger-Tang but there was no Copyright) 14 ** 15 ** AFAIK, all PA7100LC and PA7300LC platforms can use this code. 16 ** 17 ** - ggg 18 */ 19 20 #include <linux/init.h> 21 #include <linux/gfp.h> 22 #include <linux/mm.h> 23 #include <linux/pci.h> 24 #include <linux/proc_fs.h> 25 #include <linux/seq_file.h> 26 #include <linux/string.h> 27 #include <linux/types.h> 28 #include <linux/scatterlist.h> 29 30 #include <asm/cacheflush.h> 31 #include <asm/dma.h> /* for DMA_CHUNK_SIZE */ 32 #include <asm/io.h> 33 #include <asm/page.h> /* get_order */ 34 #include <asm/pgalloc.h> 35 #include <asm/uaccess.h> 36 #include <asm/tlbflush.h> /* for purge_tlb_*() macros */ 37 38 static struct proc_dir_entry * proc_gsc_root __read_mostly = NULL; 39 static unsigned long pcxl_used_bytes __read_mostly = 0; 40 static unsigned long pcxl_used_pages __read_mostly = 0; 41 42 extern unsigned long pcxl_dma_start; /* Start of pcxl dma mapping area */ 43 static spinlock_t pcxl_res_lock; 44 static char *pcxl_res_map; 45 static int pcxl_res_hint; 46 static int pcxl_res_size; 47 48 #ifdef DEBUG_PCXL_RESOURCE 49 #define DBG_RES(x...) printk(x) 50 #else 51 #define DBG_RES(x...) 52 #endif 53 54 55 /* 56 ** Dump a hex representation of the resource map. 57 */ 58 59 #ifdef DUMP_RESMAP 60 static 61 void dump_resmap(void) 62 { 63 u_long *res_ptr = (unsigned long *)pcxl_res_map; 64 u_long i = 0; 65 66 printk("res_map: "); 67 for(; i < (pcxl_res_size / sizeof(unsigned long)); ++i, ++res_ptr) 68 printk("%08lx ", *res_ptr); 69 70 printk("\n"); 71 } 72 #else 73 static inline void dump_resmap(void) {;} 74 #endif 75 76 static int pa11_dma_supported( struct device *dev, u64 mask) 77 { 78 return 1; 79 } 80 81 static inline int map_pte_uncached(pte_t * pte, 82 unsigned long vaddr, 83 unsigned long size, unsigned long *paddr_ptr) 84 { 85 unsigned long end; 86 unsigned long orig_vaddr = vaddr; 87 88 vaddr &= ~PMD_MASK; 89 end = vaddr + size; 90 if (end > PMD_SIZE) 91 end = PMD_SIZE; 92 do { 93 unsigned long flags; 94 95 if (!pte_none(*pte)) 96 printk(KERN_ERR "map_pte_uncached: page already exists\n"); 97 set_pte(pte, __mk_pte(*paddr_ptr, PAGE_KERNEL_UNC)); 98 purge_tlb_start(flags); 99 pdtlb_kernel(orig_vaddr); 100 purge_tlb_end(flags); 101 vaddr += PAGE_SIZE; 102 orig_vaddr += PAGE_SIZE; 103 (*paddr_ptr) += PAGE_SIZE; 104 pte++; 105 } while (vaddr < end); 106 return 0; 107 } 108 109 static inline int map_pmd_uncached(pmd_t * pmd, unsigned long vaddr, 110 unsigned long size, unsigned long *paddr_ptr) 111 { 112 unsigned long end; 113 unsigned long orig_vaddr = vaddr; 114 115 vaddr &= ~PGDIR_MASK; 116 end = vaddr + size; 117 if (end > PGDIR_SIZE) 118 end = PGDIR_SIZE; 119 do { 120 pte_t * pte = pte_alloc_kernel(pmd, vaddr); 121 if (!pte) 122 return -ENOMEM; 123 if (map_pte_uncached(pte, orig_vaddr, end - vaddr, paddr_ptr)) 124 return -ENOMEM; 125 vaddr = (vaddr + PMD_SIZE) & PMD_MASK; 126 orig_vaddr += PMD_SIZE; 127 pmd++; 128 } while (vaddr < end); 129 return 0; 130 } 131 132 static inline int map_uncached_pages(unsigned long vaddr, unsigned long size, 133 unsigned long paddr) 134 { 135 pgd_t * dir; 136 unsigned long end = vaddr + size; 137 138 dir = pgd_offset_k(vaddr); 139 do { 140 pmd_t *pmd; 141 142 pmd = pmd_alloc(NULL, dir, vaddr); 143 if (!pmd) 144 return -ENOMEM; 145 if (map_pmd_uncached(pmd, vaddr, end - vaddr, &paddr)) 146 return -ENOMEM; 147 vaddr = vaddr + PGDIR_SIZE; 148 dir++; 149 } while (vaddr && (vaddr < end)); 150 return 0; 151 } 152 153 static inline void unmap_uncached_pte(pmd_t * pmd, unsigned long vaddr, 154 unsigned long size) 155 { 156 pte_t * pte; 157 unsigned long end; 158 unsigned long orig_vaddr = vaddr; 159 160 if (pmd_none(*pmd)) 161 return; 162 if (pmd_bad(*pmd)) { 163 pmd_ERROR(*pmd); 164 pmd_clear(pmd); 165 return; 166 } 167 pte = pte_offset_map(pmd, vaddr); 168 vaddr &= ~PMD_MASK; 169 end = vaddr + size; 170 if (end > PMD_SIZE) 171 end = PMD_SIZE; 172 do { 173 unsigned long flags; 174 pte_t page = *pte; 175 176 pte_clear(&init_mm, vaddr, pte); 177 purge_tlb_start(flags); 178 pdtlb_kernel(orig_vaddr); 179 purge_tlb_end(flags); 180 vaddr += PAGE_SIZE; 181 orig_vaddr += PAGE_SIZE; 182 pte++; 183 if (pte_none(page) || pte_present(page)) 184 continue; 185 printk(KERN_CRIT "Whee.. Swapped out page in kernel page table\n"); 186 } while (vaddr < end); 187 } 188 189 static inline void unmap_uncached_pmd(pgd_t * dir, unsigned long vaddr, 190 unsigned long size) 191 { 192 pmd_t * pmd; 193 unsigned long end; 194 unsigned long orig_vaddr = vaddr; 195 196 if (pgd_none(*dir)) 197 return; 198 if (pgd_bad(*dir)) { 199 pgd_ERROR(*dir); 200 pgd_clear(dir); 201 return; 202 } 203 pmd = pmd_offset(dir, vaddr); 204 vaddr &= ~PGDIR_MASK; 205 end = vaddr + size; 206 if (end > PGDIR_SIZE) 207 end = PGDIR_SIZE; 208 do { 209 unmap_uncached_pte(pmd, orig_vaddr, end - vaddr); 210 vaddr = (vaddr + PMD_SIZE) & PMD_MASK; 211 orig_vaddr += PMD_SIZE; 212 pmd++; 213 } while (vaddr < end); 214 } 215 216 static void unmap_uncached_pages(unsigned long vaddr, unsigned long size) 217 { 218 pgd_t * dir; 219 unsigned long end = vaddr + size; 220 221 dir = pgd_offset_k(vaddr); 222 do { 223 unmap_uncached_pmd(dir, vaddr, end - vaddr); 224 vaddr = vaddr + PGDIR_SIZE; 225 dir++; 226 } while (vaddr && (vaddr < end)); 227 } 228 229 #define PCXL_SEARCH_LOOP(idx, mask, size) \ 230 for(; res_ptr < res_end; ++res_ptr) \ 231 { \ 232 if(0 == ((*res_ptr) & mask)) { \ 233 *res_ptr |= mask; \ 234 idx = (int)((u_long)res_ptr - (u_long)pcxl_res_map); \ 235 pcxl_res_hint = idx + (size >> 3); \ 236 goto resource_found; \ 237 } \ 238 } 239 240 #define PCXL_FIND_FREE_MAPPING(idx, mask, size) { \ 241 u##size *res_ptr = (u##size *)&(pcxl_res_map[pcxl_res_hint & ~((size >> 3) - 1)]); \ 242 u##size *res_end = (u##size *)&pcxl_res_map[pcxl_res_size]; \ 243 PCXL_SEARCH_LOOP(idx, mask, size); \ 244 res_ptr = (u##size *)&pcxl_res_map[0]; \ 245 PCXL_SEARCH_LOOP(idx, mask, size); \ 246 } 247 248 unsigned long 249 pcxl_alloc_range(size_t size) 250 { 251 int res_idx; 252 u_long mask, flags; 253 unsigned int pages_needed = size >> PAGE_SHIFT; 254 255 mask = (u_long) -1L; 256 mask >>= BITS_PER_LONG - pages_needed; 257 258 DBG_RES("pcxl_alloc_range() size: %d pages_needed %d pages_mask 0x%08lx\n", 259 size, pages_needed, mask); 260 261 spin_lock_irqsave(&pcxl_res_lock, flags); 262 263 if(pages_needed <= 8) { 264 PCXL_FIND_FREE_MAPPING(res_idx, mask, 8); 265 } else if(pages_needed <= 16) { 266 PCXL_FIND_FREE_MAPPING(res_idx, mask, 16); 267 } else if(pages_needed <= 32) { 268 PCXL_FIND_FREE_MAPPING(res_idx, mask, 32); 269 } else { 270 panic("%s: pcxl_alloc_range() Too many pages to map.\n", 271 __FILE__); 272 } 273 274 dump_resmap(); 275 panic("%s: pcxl_alloc_range() out of dma mapping resources\n", 276 __FILE__); 277 278 resource_found: 279 280 DBG_RES("pcxl_alloc_range() res_idx %d mask 0x%08lx res_hint: %d\n", 281 res_idx, mask, pcxl_res_hint); 282 283 pcxl_used_pages += pages_needed; 284 pcxl_used_bytes += ((pages_needed >> 3) ? (pages_needed >> 3) : 1); 285 286 spin_unlock_irqrestore(&pcxl_res_lock, flags); 287 288 dump_resmap(); 289 290 /* 291 ** return the corresponding vaddr in the pcxl dma map 292 */ 293 return (pcxl_dma_start + (res_idx << (PAGE_SHIFT + 3))); 294 } 295 296 #define PCXL_FREE_MAPPINGS(idx, m, size) \ 297 u##size *res_ptr = (u##size *)&(pcxl_res_map[(idx) + (((size >> 3) - 1) & (~((size >> 3) - 1)))]); \ 298 /* BUG_ON((*res_ptr & m) != m); */ \ 299 *res_ptr &= ~m; 300 301 /* 302 ** clear bits in the pcxl resource map 303 */ 304 static void 305 pcxl_free_range(unsigned long vaddr, size_t size) 306 { 307 u_long mask, flags; 308 unsigned int res_idx = (vaddr - pcxl_dma_start) >> (PAGE_SHIFT + 3); 309 unsigned int pages_mapped = size >> PAGE_SHIFT; 310 311 mask = (u_long) -1L; 312 mask >>= BITS_PER_LONG - pages_mapped; 313 314 DBG_RES("pcxl_free_range() res_idx: %d size: %d pages_mapped %d mask 0x%08lx\n", 315 res_idx, size, pages_mapped, mask); 316 317 spin_lock_irqsave(&pcxl_res_lock, flags); 318 319 if(pages_mapped <= 8) { 320 PCXL_FREE_MAPPINGS(res_idx, mask, 8); 321 } else if(pages_mapped <= 16) { 322 PCXL_FREE_MAPPINGS(res_idx, mask, 16); 323 } else if(pages_mapped <= 32) { 324 PCXL_FREE_MAPPINGS(res_idx, mask, 32); 325 } else { 326 panic("%s: pcxl_free_range() Too many pages to unmap.\n", 327 __FILE__); 328 } 329 330 pcxl_used_pages -= (pages_mapped ? pages_mapped : 1); 331 pcxl_used_bytes -= ((pages_mapped >> 3) ? (pages_mapped >> 3) : 1); 332 333 spin_unlock_irqrestore(&pcxl_res_lock, flags); 334 335 dump_resmap(); 336 } 337 338 static int proc_pcxl_dma_show(struct seq_file *m, void *v) 339 { 340 #if 0 341 u_long i = 0; 342 unsigned long *res_ptr = (u_long *)pcxl_res_map; 343 #endif 344 unsigned long total_pages = pcxl_res_size << 3; /* 8 bits per byte */ 345 346 seq_printf(m, "\nDMA Mapping Area size : %d bytes (%ld pages)\n", 347 PCXL_DMA_MAP_SIZE, total_pages); 348 349 seq_printf(m, "Resource bitmap : %d bytes\n", pcxl_res_size); 350 351 seq_puts(m, " total: free: used: % used:\n"); 352 seq_printf(m, "blocks %8d %8ld %8ld %8ld%%\n", pcxl_res_size, 353 pcxl_res_size - pcxl_used_bytes, pcxl_used_bytes, 354 (pcxl_used_bytes * 100) / pcxl_res_size); 355 356 seq_printf(m, "pages %8ld %8ld %8ld %8ld%%\n", total_pages, 357 total_pages - pcxl_used_pages, pcxl_used_pages, 358 (pcxl_used_pages * 100 / total_pages)); 359 360 #if 0 361 seq_puts(m, "\nResource bitmap:"); 362 363 for(; i < (pcxl_res_size / sizeof(u_long)); ++i, ++res_ptr) { 364 if ((i & 7) == 0) 365 seq_puts(m,"\n "); 366 seq_printf(m, "%s %08lx", buf, *res_ptr); 367 } 368 #endif 369 seq_putc(m, '\n'); 370 return 0; 371 } 372 373 static int proc_pcxl_dma_open(struct inode *inode, struct file *file) 374 { 375 return single_open(file, proc_pcxl_dma_show, NULL); 376 } 377 378 static const struct file_operations proc_pcxl_dma_ops = { 379 .owner = THIS_MODULE, 380 .open = proc_pcxl_dma_open, 381 .read = seq_read, 382 .llseek = seq_lseek, 383 .release = single_release, 384 }; 385 386 static int __init 387 pcxl_dma_init(void) 388 { 389 if (pcxl_dma_start == 0) 390 return 0; 391 392 spin_lock_init(&pcxl_res_lock); 393 pcxl_res_size = PCXL_DMA_MAP_SIZE >> (PAGE_SHIFT + 3); 394 pcxl_res_hint = 0; 395 pcxl_res_map = (char *)__get_free_pages(GFP_KERNEL, 396 get_order(pcxl_res_size)); 397 memset(pcxl_res_map, 0, pcxl_res_size); 398 proc_gsc_root = proc_mkdir("gsc", NULL); 399 if (!proc_gsc_root) 400 printk(KERN_WARNING 401 "pcxl_dma_init: Unable to create gsc /proc dir entry\n"); 402 else { 403 struct proc_dir_entry* ent; 404 ent = proc_create("pcxl_dma", 0, proc_gsc_root, 405 &proc_pcxl_dma_ops); 406 if (!ent) 407 printk(KERN_WARNING 408 "pci-dma.c: Unable to create pcxl_dma /proc entry.\n"); 409 } 410 return 0; 411 } 412 413 __initcall(pcxl_dma_init); 414 415 static void * pa11_dma_alloc_consistent (struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t flag) 416 { 417 unsigned long vaddr; 418 unsigned long paddr; 419 int order; 420 421 order = get_order(size); 422 size = 1 << (order + PAGE_SHIFT); 423 vaddr = pcxl_alloc_range(size); 424 paddr = __get_free_pages(flag, order); 425 flush_kernel_dcache_range(paddr, size); 426 paddr = __pa(paddr); 427 map_uncached_pages(vaddr, size, paddr); 428 *dma_handle = (dma_addr_t) paddr; 429 430 #if 0 431 /* This probably isn't needed to support EISA cards. 432 ** ISA cards will certainly only support 24-bit DMA addressing. 433 ** Not clear if we can, want, or need to support ISA. 434 */ 435 if (!dev || *dev->coherent_dma_mask < 0xffffffff) 436 gfp |= GFP_DMA; 437 #endif 438 return (void *)vaddr; 439 } 440 441 static void pa11_dma_free_consistent (struct device *dev, size_t size, void *vaddr, dma_addr_t dma_handle) 442 { 443 int order; 444 445 order = get_order(size); 446 size = 1 << (order + PAGE_SHIFT); 447 unmap_uncached_pages((unsigned long)vaddr, size); 448 pcxl_free_range((unsigned long)vaddr, size); 449 free_pages((unsigned long)__va(dma_handle), order); 450 } 451 452 static dma_addr_t pa11_dma_map_single(struct device *dev, void *addr, size_t size, enum dma_data_direction direction) 453 { 454 BUG_ON(direction == DMA_NONE); 455 456 flush_kernel_dcache_range((unsigned long) addr, size); 457 return virt_to_phys(addr); 458 } 459 460 static void pa11_dma_unmap_single(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction direction) 461 { 462 BUG_ON(direction == DMA_NONE); 463 464 if (direction == DMA_TO_DEVICE) 465 return; 466 467 /* 468 * For PCI_DMA_FROMDEVICE this flush is not necessary for the 469 * simple map/unmap case. However, it IS necessary if if 470 * pci_dma_sync_single_* has been called and the buffer reused. 471 */ 472 473 flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle), size); 474 return; 475 } 476 477 static int pa11_dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction) 478 { 479 int i; 480 481 BUG_ON(direction == DMA_NONE); 482 483 for (i = 0; i < nents; i++, sglist++ ) { 484 unsigned long vaddr = sg_virt_addr(sglist); 485 sg_dma_address(sglist) = (dma_addr_t) virt_to_phys(vaddr); 486 sg_dma_len(sglist) = sglist->length; 487 flush_kernel_dcache_range(vaddr, sglist->length); 488 } 489 return nents; 490 } 491 492 static void pa11_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction) 493 { 494 int i; 495 496 BUG_ON(direction == DMA_NONE); 497 498 if (direction == DMA_TO_DEVICE) 499 return; 500 501 /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */ 502 503 for (i = 0; i < nents; i++, sglist++ ) 504 flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length); 505 return; 506 } 507 508 static void pa11_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, unsigned long offset, size_t size, enum dma_data_direction direction) 509 { 510 BUG_ON(direction == DMA_NONE); 511 512 flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle) + offset, size); 513 } 514 515 static void pa11_dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle, unsigned long offset, size_t size, enum dma_data_direction direction) 516 { 517 BUG_ON(direction == DMA_NONE); 518 519 flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle) + offset, size); 520 } 521 522 static void pa11_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction) 523 { 524 int i; 525 526 /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */ 527 528 for (i = 0; i < nents; i++, sglist++ ) 529 flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length); 530 } 531 532 static void pa11_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction) 533 { 534 int i; 535 536 /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */ 537 538 for (i = 0; i < nents; i++, sglist++ ) 539 flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length); 540 } 541 542 struct hppa_dma_ops pcxl_dma_ops = { 543 .dma_supported = pa11_dma_supported, 544 .alloc_consistent = pa11_dma_alloc_consistent, 545 .alloc_noncoherent = pa11_dma_alloc_consistent, 546 .free_consistent = pa11_dma_free_consistent, 547 .map_single = pa11_dma_map_single, 548 .unmap_single = pa11_dma_unmap_single, 549 .map_sg = pa11_dma_map_sg, 550 .unmap_sg = pa11_dma_unmap_sg, 551 .dma_sync_single_for_cpu = pa11_dma_sync_single_for_cpu, 552 .dma_sync_single_for_device = pa11_dma_sync_single_for_device, 553 .dma_sync_sg_for_cpu = pa11_dma_sync_sg_for_cpu, 554 .dma_sync_sg_for_device = pa11_dma_sync_sg_for_device, 555 }; 556 557 static void *fail_alloc_consistent(struct device *dev, size_t size, 558 dma_addr_t *dma_handle, gfp_t flag) 559 { 560 return NULL; 561 } 562 563 static void *pa11_dma_alloc_noncoherent(struct device *dev, size_t size, 564 dma_addr_t *dma_handle, gfp_t flag) 565 { 566 void *addr; 567 568 addr = (void *)__get_free_pages(flag, get_order(size)); 569 if (addr) 570 *dma_handle = (dma_addr_t)virt_to_phys(addr); 571 572 return addr; 573 } 574 575 static void pa11_dma_free_noncoherent(struct device *dev, size_t size, 576 void *vaddr, dma_addr_t iova) 577 { 578 free_pages((unsigned long)vaddr, get_order(size)); 579 return; 580 } 581 582 struct hppa_dma_ops pcx_dma_ops = { 583 .dma_supported = pa11_dma_supported, 584 .alloc_consistent = fail_alloc_consistent, 585 .alloc_noncoherent = pa11_dma_alloc_noncoherent, 586 .free_consistent = pa11_dma_free_noncoherent, 587 .map_single = pa11_dma_map_single, 588 .unmap_single = pa11_dma_unmap_single, 589 .map_sg = pa11_dma_map_sg, 590 .unmap_sg = pa11_dma_unmap_sg, 591 .dma_sync_single_for_cpu = pa11_dma_sync_single_for_cpu, 592 .dma_sync_single_for_device = pa11_dma_sync_single_for_device, 593 .dma_sync_sg_for_cpu = pa11_dma_sync_sg_for_cpu, 594 .dma_sync_sg_for_device = pa11_dma_sync_sg_for_device, 595 }; 596