arch/parisc/kernel/pci-dma.c

   1 /*
   2 ** Dynamic DMA mapping support.
   3 ** See Documentation/DMA-mapping.txt for interface definitions.
   4 **
   5 **      (c) Copyright 1999,2000 Hewlett-Packard Company
   6 **      (c) Copyright 2000 Grant Grundler
   7 **      (c) Copyright 2000 Philipp Rumpf <prumpf@tux.org>
   8 **      (c) Copyright 2000 John Marvin
   9 **
  10 ** This implementation is for PA-RISC platforms that do not support
  11 ** I/O TLBs (aka DMA address translation hardware).
  12 **
  13 ** "leveraged" from 2.3.47: arch/ia64/kernel/pci-dma.c.
  14 ** (I assume it's from David Mosberger-Tang but there was no Copyright)
  15 **
  16 ** AFAIK, all PA7100LC and PA7300LC platforms can use this code.
  17 ** All PA2.0 machines but V-class can alias xxx_alloc_consistent()
  18 ** to use regular cacheable memory.
  19 **
  20 ** - ggg
  21 */
  22
  23 #include <linux/types.h>
  24 #include <linux/mm.h>
  25 #include <linux/string.h>
  26 #include <linux/pci.h>
  27 #include <linux/init.h>
  28
  29 #include <linux/malloc.h>
  30 #include <linux/vmalloc.h>
  31
  32 #include <asm/uaccess.h>
  33 #include <asm/pgalloc.h>
  34
  35 #include <asm/io.h>
  36 #include <asm/page.h>   /* get_order */
  37 #include <asm/dma.h>    /* for DMA_CHUNK_SIZE */
  38
  39 #include <linux/proc_fs.h>
  40
  41 static struct proc_dir_entry * proc_gsc_root = NULL;
  42 static int pcxl_proc_info(char *buffer, char **start, off_t offset, int length);
  43 static unsigned long pcxl_used_bytes = 0;
  44 static unsigned long pcxl_used_pages = 0;
  45
  46 extern unsigned long pcxl_dma_start; /* Start of pcxl dma mapping area */
  47 static spinlock_t   pcxl_res_lock;
  48 static char    *pcxl_res_map;
  49 static int     pcxl_res_hint;
  50 static int     pcxl_res_size;
  51
  52 #ifdef DEBUG_PCXL_RESOURCE
  53 #define DBG_RES(x...)   printk(x)
  54 #else
  55 #define DBG_RES(x...)
  56 #endif
  57
  58
  59 /*
  60 ** Dump a hex representation of the resource map.
  61 */
  62
  63 #ifdef DUMP_RESMAP
  64 static
  65 void dump_resmap(void)
  66 {
  67         u_long *res_ptr = (unsigned long *)pcxl_res_map;
  68         u_long i = 0;
  69
  70         printk("res_map: ");
  71         for(; i < (pcxl_res_size / sizeof(unsigned long)); ++i, ++res_ptr)
  72                 printk("%08lx ", *res_ptr);
  73
  74         printk("\n");
  75 }
  76 #else
  77 static inline void dump_resmap(void) {;}
  78 #endif
  79
  80 static int pa11_dma_supported( struct pci_dev *dev, dma_addr_t mask)
  81 {
  82         return 1;
  83 }
  84
  85 static inline int map_pte_uncached(pte_t * pte,
  86                 unsigned long vaddr,
  87                 unsigned long size, unsigned long *paddr_ptr)
  88 {
  89         unsigned long end;
  90         unsigned long orig_vaddr = vaddr;
  91
  92         vaddr &= ~PMD_MASK;
  93         end = vaddr + size;
  94         if (end > PMD_SIZE)
  95                 end = PMD_SIZE;
  96         do {
  97                 if (!pte_none(*pte))
  98                         printk(KERN_ERR "map_pte_uncached: page already exists\n");
  99                 set_pte(pte, __mk_pte(*paddr_ptr, PAGE_KERNEL_UNC));
 100                 pdtlb_kernel(orig_vaddr);
 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_kernel(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(pmd, vaddr);
 168         vaddr &= ~PMD_MASK;
 169         end = vaddr + size;
 170         if (end > PMD_SIZE)
 171                 end = PMD_SIZE;
 172         do {
 173                 pte_t page = *pte;
 174                 pte_clear(pte);
 175                 pdtlb_kernel(orig_vaddr);
 176                 vaddr += PAGE_SIZE;
 177                 orig_vaddr += PAGE_SIZE;
 178                 pte++;
 179                 if (pte_none(page) || pte_present(page))
 180                         continue;
 181                 printk(KERN_CRIT "Whee.. Swapped out page in kernel page table\n");
 182         } while (vaddr < end);
 183 }
 184
 185 static inline void unmap_uncached_pmd(pgd_t * dir, unsigned long vaddr,
 186                 unsigned long size)
 187 {
 188         pmd_t * pmd;
 189         unsigned long end;
 190         unsigned long orig_vaddr = vaddr;
 191
 192         if (pgd_none(*dir))
 193                 return;
 194         if (pgd_bad(*dir)) {
 195                 pgd_ERROR(*dir);
 196                 pgd_clear(dir);
 197                 return;
 198         }
 199         pmd = pmd_offset(dir, vaddr);
 200         vaddr &= ~PGDIR_MASK;
 201         end = vaddr + size;
 202         if (end > PGDIR_SIZE)
 203                 end = PGDIR_SIZE;
 204         do {
 205                 unmap_uncached_pte(pmd, orig_vaddr, end - vaddr);
 206                 vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
 207                 orig_vaddr += PMD_SIZE;
 208                 pmd++;
 209         } while (vaddr < end);
 210 }
 211
 212 static void unmap_uncached_pages(unsigned long vaddr, unsigned long size)
 213 {
 214         pgd_t * dir;
 215         unsigned long end = vaddr + size;
 216
 217         dir = pgd_offset_k(vaddr);
 218         do {
 219                 unmap_uncached_pmd(dir, vaddr, end - vaddr);
 220                 vaddr = vaddr + PGDIR_SIZE;
 221                 dir++;
 222         } while (vaddr && (vaddr < end));
 223 }
 224
 225 #define PCXL_SEARCH_LOOP(idx, mask, size)  \
 226        for(; res_ptr < res_end; ++res_ptr) \
 227        { \
 228                if(0 == ((*res_ptr) & mask)) { \
 229                        *res_ptr |= mask; \
 230                        idx = (int)((u_long)res_ptr - (u_long)pcxl_res_map); \
 231                        pcxl_res_hint = idx + (size >> 3); \
 232                        goto resource_found; \
 233                } \
 234        }
 235
 236 #define PCXL_FIND_FREE_MAPPING(idx, mask, size)  { \
 237        u##size *res_ptr = (u##size *)&(pcxl_res_map[pcxl_res_hint & ~((size >> 3) - 1)]); \
 238        u##size *res_end = (u##size *)&pcxl_res_map[pcxl_res_size]; \
 239        PCXL_SEARCH_LOOP(idx, mask, size); \
 240        res_ptr = (u##size *)&pcxl_res_map[0]; \
 241        PCXL_SEARCH_LOOP(idx, mask, size); \
 242 }
 243
 244 unsigned long
 245 pcxl_alloc_range(size_t size)
 246 {
 247         int res_idx;
 248         u_long mask, flags;
 249         unsigned int pages_needed = size >> PAGE_SHIFT;
 250
 251         ASSERT(pages_needed);
 252         ASSERT((pages_needed * PAGE_SIZE) < DMA_CHUNK_SIZE);
 253         ASSERT(pages_needed < (BITS_PER_LONG - 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(__FILE__ ": pcxl_alloc_range() Too many pages to map.\n");
 271         }
 272
 273         dump_resmap();
 274         panic(__FILE__ ": pcxl_alloc_range() out of dma mapping resources\n");
 275
 276 resource_found:
 277
 278         DBG_RES("pcxl_alloc_range() res_idx %d mask 0x%08lx res_hint: %d\n",
 279                 res_idx, mask, pcxl_res_hint);
 280
 281         pcxl_used_pages += pages_needed;
 282         pcxl_used_bytes += ((pages_needed >> 3) ? (pages_needed >> 3) : 1);
 283
 284         spin_unlock_irqrestore(&pcxl_res_lock, flags);
 285
 286         dump_resmap();
 287
 288         /*
 289         ** return the corresponding vaddr in the pcxl dma map
 290         */
 291         return (pcxl_dma_start + (res_idx << (PAGE_SHIFT + 3)));
 292 }
 293
 294 #define PCXL_FREE_MAPPINGS(idx, m, size) \
 295                 u##size *res_ptr = (u##size *)&(pcxl_res_map[(idx) + (((size >> 3) - 1) & (~((size >> 3) - 1)))]); \
 296                 ASSERT((*res_ptr & m) == m); \
 297                 *res_ptr &= ~m;
 298
 299 /*
 300 ** clear bits in the pcxl resource map
 301 */
 302 static void
 303 pcxl_free_range(unsigned long vaddr, size_t size)
 304 {
 305         u_long mask, flags;
 306         unsigned int res_idx = (vaddr - pcxl_dma_start) >> (PAGE_SHIFT + 3);
 307         unsigned int pages_mapped = size >> PAGE_SHIFT;
 308
 309         ASSERT(pages_mapped);
 310         ASSERT((pages_mapped * PAGE_SIZE) < DMA_CHUNK_SIZE);
 311         ASSERT(pages_mapped < (BITS_PER_LONG - PAGE_SHIFT));
 312
 313         mask = (u_long) -1L;
 314         mask >>= BITS_PER_LONG - pages_mapped;
 315
 316         DBG_RES("pcxl_free_range() res_idx: %d size: %d pages_mapped %d mask 0x%08lx\n",
 317                 res_idx, size, pages_mapped, mask);
 318
 319         spin_lock_irqsave(&pcxl_res_lock, flags);
 320
 321         if(pages_mapped <= 8) {
 322                 PCXL_FREE_MAPPINGS(res_idx, mask, 8);
 323         } else if(pages_mapped <= 16) {
 324                 PCXL_FREE_MAPPINGS(res_idx, mask, 16);
 325         } else if(pages_mapped <= 32) {
 326                 PCXL_FREE_MAPPINGS(res_idx, mask, 32);
 327         } else {
 328                 panic(__FILE__ ": pcxl_free_range() Too many pages to unmap.\n");
 329         }
 330
 331         pcxl_used_pages -= (pages_mapped ? pages_mapped : 1);
 332         pcxl_used_bytes -= ((pages_mapped >> 3) ? (pages_mapped >> 3) : 1);
 333
 334         spin_unlock_irqrestore(&pcxl_res_lock, flags);
 335
 336         dump_resmap();
 337 }
 338
 339 static int __init
 340 pcxl_dma_init(void)
 341 {
 342     if (pcxl_dma_start == 0)
 343         return 0;
 344
 345     spin_lock_init(&pcxl_res_lock);
 346     pcxl_res_size = PCXL_DMA_MAP_SIZE >> (PAGE_SHIFT + 3);
 347     pcxl_res_hint = 0;
 348     pcxl_res_map = (char *)__get_free_pages(GFP_KERNEL,
 349                                             get_order(pcxl_res_size));
 350
 351     proc_gsc_root = proc_mkdir("gsc", 0);
 352     create_proc_info_entry("dino", 0, proc_gsc_root, pcxl_proc_info);
 353     return 0;
 354 }
 355
 356 __initcall(pcxl_dma_init);
 357
 358 static void * pa11_dma_alloc_consistent (struct pci_dev *hwdev, size_t size, dma_addr_t *dma_handle)
 359 {
 360         unsigned long vaddr;
 361         unsigned long paddr;
 362         int order;
 363
 364         order = get_order(size);
 365         size = 1 << (order + PAGE_SHIFT);
 366         vaddr = pcxl_alloc_range(size);
 367         paddr = __get_free_pages(GFP_ATOMIC, order);
 368         flush_kernel_dcache_range(paddr, size);
 369         paddr = __pa(paddr);
 370         map_uncached_pages(vaddr, size, paddr);
 371         *dma_handle = (dma_addr_t) paddr;
 372
 373 #if 0
 374 /* This probably isn't needed to support EISA cards.
 375 ** ISA cards will certainly only support 24-bit DMA addressing.
 376 ** Not clear if we can, want, or need to support ISA.
 377 */
 378         if (!hwdev || hwdev->dma_mask != 0xffffffff)
 379                 gfp |= GFP_DMA;
 380 #endif
 381         return (void *)vaddr;
 382 }
 383
 384 static void pa11_dma_free_consistent (struct pci_dev *hwdev, size_t size, void *vaddr, dma_addr_t dma_handle)
 385 {
 386         int order;
 387
 388         order = get_order(size);
 389         size = 1 << (order + PAGE_SHIFT);
 390         unmap_uncached_pages((unsigned long)vaddr, size);
 391         pcxl_free_range((unsigned long)vaddr, size);
 392         free_pages((unsigned long)__va(dma_handle), order);
 393 }
 394
 395 static dma_addr_t pa11_dma_map_single(struct pci_dev *dev, void *addr, size_t size, int direction)
 396 {
 397         if (direction == PCI_DMA_NONE) {
 398                 printk(KERN_ERR "pa11_dma_map_single(PCI_DMA_NONE) called by %p\n", __builtin_return_address(0));
 399                 BUG();
 400         }
 401
 402         flush_kernel_dcache_range((unsigned long) addr, size);
 403         return virt_to_phys(addr);
 404 }
 405
 406 static void pa11_dma_unmap_single(struct pci_dev *dev, dma_addr_t dma_handle, size_t size, int direction)
 407 {
 408         if (direction == PCI_DMA_NONE) {
 409                 printk(KERN_ERR "pa11_dma_unmap_single(PCI_DMA_NONE) called by %p\n", __builtin_return_address(0));
 410                 BUG();
 411         }
 412
 413         if (direction == PCI_DMA_TODEVICE)
 414             return;
 415
 416         /*
 417          * For PCI_DMA_FROMDEVICE this flush is not necessary for the
 418          * simple map/unmap case. However, it IS necessary if if
 419          * pci_dma_sync_single has been called and the buffer reused.
 420          */
 421
 422         flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle), size);
 423         return;
 424 }
 425
 426 static int pa11_dma_map_sg(struct pci_dev *dev, struct scatterlist *sglist, int nents, int direction)
 427 {
 428         int i;
 429
 430         if (direction == PCI_DMA_NONE)
 431             BUG();
 432
 433         for (i = 0; i < nents; i++, sglist++ ) {
 434                 sg_dma_address(sglist) = (dma_addr_t) virt_to_phys(sglist->address);
 435                 sg_dma_len(sglist) = sglist->length;
 436                 flush_kernel_dcache_range((unsigned long)sglist->address,
 437                                 sglist->length);
 438         }
 439         return nents;
 440 }
 441
 442 static void pa11_dma_unmap_sg(struct pci_dev *dev, struct scatterlist *sglist, int nents, int direction)
 443 {
 444         int i;
 445
 446         if (direction == PCI_DMA_NONE)
 447             BUG();
 448
 449         if (direction == PCI_DMA_TODEVICE)
 450             return;
 451
 452         /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
 453
 454         for (i = 0; i < nents; i++, sglist++ )
 455                 flush_kernel_dcache_range((unsigned long) sglist->address, sglist->length);
 456         return;
 457 }
 458
 459 static void pa11_dma_sync_single(struct pci_dev *dev, dma_addr_t dma_handle, size_t size, int direction)
 460 {
 461         if (direction == PCI_DMA_NONE)
 462             BUG();
 463
 464         flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle), size);
 465 }
 466
 467 static void pa11_dma_sync_sg(struct pci_dev *dev, struct scatterlist *sglist, int nents, int direction)
 468 {
 469         int i;
 470
 471         /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
 472
 473         for (i = 0; i < nents; i++, sglist++ )
 474                 flush_kernel_dcache_range((unsigned long) sglist->address, sglist->length);
 475 }
 476
 477 struct pci_dma_ops pcxl_dma_ops = {
 478         pa11_dma_supported,                     /* dma_support */
 479         pa11_dma_alloc_consistent,
 480         pa11_dma_free_consistent,
 481         pa11_dma_map_single,                    /* map_single */
 482         pa11_dma_unmap_single,                  /* unmap_single */
 483         pa11_dma_map_sg,                        /* map_sg */
 484         pa11_dma_unmap_sg,                      /* unmap_sg */
 485         pa11_dma_sync_single,                   /* dma_sync_single */
 486         pa11_dma_sync_sg                        /* dma_sync_sg */
 487 };
 488
 489 static void *fail_alloc_consistent(struct pci_dev *hwdev, size_t size,
 490                 dma_addr_t *dma_handle)
 491 {
 492         return NULL;
 493 }
 494
 495 static void fail_free_consistent(struct pci_dev *dev, size_t size,
 496                 void *vaddr, dma_addr_t iova)
 497 {
 498         return;
 499 }
 500
 501 struct pci_dma_ops pcx_dma_ops = {
 502         pa11_dma_supported,                     /* dma_support */
 503         fail_alloc_consistent,
 504         fail_free_consistent,
 505         pa11_dma_map_single,                    /* map_single */
 506         pa11_dma_unmap_single,                  /* unmap_single */
 507         pa11_dma_map_sg,                        /* map_sg */
 508         pa11_dma_unmap_sg,                      /* unmap_sg */
 509         pa11_dma_sync_single,                   /* dma_sync_single */
 510         pa11_dma_sync_sg                        /* dma_sync_sg */
 511 };
 512
 513 struct pci_dma_ops *hppa_dma_ops;
 514
 515 static int pcxl_proc_info(char *buf, char **start, off_t offset, int len)
 516 {
 517         u_long i = 0;
 518         unsigned long *res_ptr = (u_long *)pcxl_res_map;
 519         unsigned long total_pages = pcxl_res_size << 3;        /* 8 bits per byte */
 520
 521         sprintf(buf, "\nDMA Mapping Area size    : %d bytes (%d pages)\n",
 522                 PCXL_DMA_MAP_SIZE,
 523                 (pcxl_res_size << 3) ); /* 1 bit per page */
 524
 525         sprintf(buf, "%sResource bitmap : %d bytes (%d pages)\n",
 526                 buf, pcxl_res_size, pcxl_res_size << 3);   /* 8 bits per byte */
 527
 528         strcat(buf,  "            total:    free:    used:   % used:\n");
 529         sprintf(buf, "%sblocks  %8d %8ld %8ld %8ld%%\n", buf, pcxl_res_size,
 530                 pcxl_res_size - pcxl_used_bytes, pcxl_used_bytes,
 531                 (pcxl_used_bytes * 100) / pcxl_res_size);
 532
 533         sprintf(buf, "%spages   %8ld %8ld %8ld %8ld%%\n", buf, total_pages,
 534                 total_pages - pcxl_used_pages, pcxl_used_pages,
 535                 (pcxl_used_pages * 100 / total_pages));
 536
 537         strcat(buf, "\nResource bitmap:");
 538
 539         for(; i < (pcxl_res_size / sizeof(u_long)); ++i, ++res_ptr) {
 540                 if ((i & 7) == 0)
 541                     strcat(buf,"\n   ");
 542                 sprintf(buf, "%s %08lx", buf, *res_ptr);
 543         }
 544         strcat(buf, "\n");
 545         return strlen(buf);
 546 }
 547