arch/cris/arch-v32/drivers/axisflashmap.c

   1 /*
   2  * Physical mapping layer for MTD using the Axis partitiontable format
   3  *
   4  * Copyright (c) 2001-2007 Axis Communications AB
   5  *
   6  * This file is under the GPL.
   7  *
   8  * First partition is always sector 0 regardless of if we find a partitiontable
   9  * or not. In the start of the next sector, there can be a partitiontable that
  10  * tells us what other partitions to define. If there isn't, we use a default
  11  * partition split defined below.
  12  *
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/types.h>
  17 #include <linux/kernel.h>
  18 #include <linux/init.h>
  19 #include <linux/slab.h>
  20
  21 #include <linux/mtd/concat.h>
  22 #include <linux/mtd/map.h>
  23 #include <linux/mtd/mtd.h>
  24 #include <linux/mtd/mtdram.h>
  25 #include <linux/mtd/partitions.h>
  26
  27 #include <asm/axisflashmap.h>
  28 #include <asm/mmu.h>
  29
  30 #define MEM_CSE0_SIZE (0x04000000)
  31 #define MEM_CSE1_SIZE (0x04000000)
  32
  33 #define FLASH_UNCACHED_ADDR  KSEG_E
  34 #define FLASH_CACHED_ADDR    KSEG_F
  35
  36 #define PAGESIZE (512)
  37
  38 #if CONFIG_ETRAX_FLASH_BUSWIDTH==1
  39 #define flash_data __u8
  40 #elif CONFIG_ETRAX_FLASH_BUSWIDTH==2
  41 #define flash_data __u16
  42 #elif CONFIG_ETRAX_FLASH_BUSWIDTH==4
  43 #define flash_data __u32
  44 #endif
  45
  46 /* From head.S */
  47 extern unsigned long romfs_in_flash; /* 1 when romfs_start, _length in flash */
  48 extern unsigned long romfs_start, romfs_length;
  49 extern unsigned long nand_boot; /* 1 when booted from nand flash */
  50
  51 struct partition_name {
  52         char name[6];
  53 };
  54
  55 /* The master mtd for the entire flash. */
  56 struct mtd_info* axisflash_mtd = NULL;
  57
  58 /* Map driver functions. */
  59
  60 static map_word flash_read(struct map_info *map, unsigned long ofs)
  61 {
  62         map_word tmp;
  63         tmp.x[0] = *(flash_data *)(map->map_priv_1 + ofs);
  64         return tmp;
  65 }
  66
  67 static void flash_copy_from(struct map_info *map, void *to,
  68                             unsigned long from, ssize_t len)
  69 {
  70         memcpy(to, (void *)(map->map_priv_1 + from), len);
  71 }
  72
  73 static void flash_write(struct map_info *map, map_word d, unsigned long adr)
  74 {
  75         *(flash_data *)(map->map_priv_1 + adr) = (flash_data)d.x[0];
  76 }
  77
  78 /*
  79  * The map for chip select e0.
  80  *
  81  * We run into tricky coherence situations if we mix cached with uncached
  82  * accesses to we only use the uncached version here.
  83  *
  84  * The size field is the total size where the flash chips may be mapped on the
  85  * chip select. MTD probes should find all devices there and it does not matter
  86  * if there are unmapped gaps or aliases (mirrors of flash devices). The MTD
  87  * probes will ignore them.
  88  *
  89  * The start address in map_priv_1 is in virtual memory so we cannot use
  90  * MEM_CSE0_START but must rely on that FLASH_UNCACHED_ADDR is the start
  91  * address of cse0.
  92  */
  93 static struct map_info map_cse0 = {
  94         .name = "cse0",
  95         .size = MEM_CSE0_SIZE,
  96         .bankwidth = CONFIG_ETRAX_FLASH_BUSWIDTH,
  97         .read = flash_read,
  98         .copy_from = flash_copy_from,
  99         .write = flash_write,
 100         .map_priv_1 = FLASH_UNCACHED_ADDR
 101 };
 102
 103 /*
 104  * The map for chip select e1.
 105  *
 106  * If there was a gap between cse0 and cse1, map_priv_1 would get the wrong
 107  * address, but there isn't.
 108  */
 109 static struct map_info map_cse1 = {
 110         .name = "cse1",
 111         .size = MEM_CSE1_SIZE,
 112         .bankwidth = CONFIG_ETRAX_FLASH_BUSWIDTH,
 113         .read = flash_read,
 114         .copy_from = flash_copy_from,
 115         .write = flash_write,
 116         .map_priv_1 = FLASH_UNCACHED_ADDR + MEM_CSE0_SIZE
 117 };
 118
 119 #define MAX_PARTITIONS                  7
 120 #ifdef CONFIG_ETRAX_NANDBOOT
 121 #define NUM_DEFAULT_PARTITIONS          4
 122 #define DEFAULT_ROOTFS_PARTITION_NO     2
 123 #define DEFAULT_MEDIA_SIZE              0x2000000 /* 32 megs */
 124 #else
 125 #define NUM_DEFAULT_PARTITIONS          3
 126 #define DEFAULT_ROOTFS_PARTITION_NO     (-1)
 127 #define DEFAULT_MEDIA_SIZE              0x800000 /* 8 megs */
 128 #endif
 129
 130 #if (MAX_PARTITIONS < NUM_DEFAULT_PARTITIONS)
 131 #error MAX_PARTITIONS must be >= than NUM_DEFAULT_PARTITIONS
 132 #endif
 133
 134 /* Initialize the ones normally used. */
 135 static struct mtd_partition axis_partitions[MAX_PARTITIONS] = {
 136         {
 137                 .name = "part0",
 138                 .size = CONFIG_ETRAX_PTABLE_SECTOR,
 139                 .offset = 0
 140         },
 141         {
 142                 .name = "part1",
 143                 .size = 0,
 144                 .offset = 0
 145         },
 146         {
 147                 .name = "part2",
 148                 .size = 0,
 149                 .offset = 0
 150         },
 151         {
 152                 .name = "part3",
 153                 .size = 0,
 154                 .offset = 0
 155         },
 156         {
 157                 .name = "part4",
 158                 .size = 0,
 159                 .offset = 0
 160         },
 161         {
 162                 .name = "part5",
 163                 .size = 0,
 164                 .offset = 0
 165         },
 166         {
 167                 .name = "part6",
 168                 .size = 0,
 169                 .offset = 0
 170         },
 171 };
 172
 173
 174 /* If no partition-table was found, we use this default-set.
 175  * Default flash size is 8MB (NOR). CONFIG_ETRAX_PTABLE_SECTOR is most
 176  * likely the size of one flash block and "filesystem"-partition needs
 177  * to be >=5 blocks to be able to use JFFS.
 178  */
 179 static struct mtd_partition axis_default_partitions[NUM_DEFAULT_PARTITIONS] = {
 180         {
 181                 .name = "boot firmware",
 182                 .size = CONFIG_ETRAX_PTABLE_SECTOR,
 183                 .offset = 0
 184         },
 185         {
 186                 .name = "kernel",
 187                 .size = 10 * CONFIG_ETRAX_PTABLE_SECTOR,
 188                 .offset = CONFIG_ETRAX_PTABLE_SECTOR
 189         },
 190 #define FILESYSTEM_SECTOR (11 * CONFIG_ETRAX_PTABLE_SECTOR)
 191 #ifdef CONFIG_ETRAX_NANDBOOT
 192         {
 193                 .name = "rootfs",
 194                 .size = 10 * CONFIG_ETRAX_PTABLE_SECTOR,
 195                 .offset = FILESYSTEM_SECTOR
 196         },
 197 #undef FILESYSTEM_SECTOR
 198 #define FILESYSTEM_SECTOR (21 * CONFIG_ETRAX_PTABLE_SECTOR)
 199 #endif
 200         {
 201                 .name = "rwfs",
 202                 .size = DEFAULT_MEDIA_SIZE - FILESYSTEM_SECTOR,
 203                 .offset = FILESYSTEM_SECTOR
 204         }
 205 };
 206
 207 #ifdef CONFIG_ETRAX_AXISFLASHMAP_MTD0WHOLE
 208 /* Main flash device */
 209 static struct mtd_partition main_partition = {
 210         .name = "main",
 211         .size = 0,
 212         .offset = 0
 213 };
 214 #endif
 215
 216 /* Auxiliary partition if we find another flash */
 217 static struct mtd_partition aux_partition = {
 218         .name = "aux",
 219         .size = 0,
 220         .offset = 0
 221 };
 222
 223 /*
 224  * Probe a chip select for AMD-compatible (JEDEC) or CFI-compatible flash
 225  * chips in that order (because the amd_flash-driver is faster).
 226  */
 227 static struct mtd_info *probe_cs(struct map_info *map_cs)
 228 {
 229         struct mtd_info *mtd_cs = NULL;
 230
 231         printk(KERN_INFO
 232                "%s: Probing a 0x%08lx bytes large window at 0x%08lx.\n",
 233                map_cs->name, map_cs->size, map_cs->map_priv_1);
 234
 235 #ifdef CONFIG_MTD_CFI
 236         mtd_cs = do_map_probe("cfi_probe", map_cs);
 237 #endif
 238 #ifdef CONFIG_MTD_JEDECPROBE
 239         if (!mtd_cs)
 240                 mtd_cs = do_map_probe("jedec_probe", map_cs);
 241 #endif
 242
 243         return mtd_cs;
 244 }
 245
 246 /*
 247  * Probe each chip select individually for flash chips. If there are chips on
 248  * both cse0 and cse1, the mtd_info structs will be concatenated to one struct
 249  * so that MTD partitions can cross chip boundaries.
 250  *
 251  * The only known restriction to how you can mount your chips is that each
 252  * chip select must hold similar flash chips. But you need external hardware
 253  * to do that anyway and you can put totally different chips on cse0 and cse1
 254  * so it isn't really much of a restriction.
 255  */
 256 extern struct mtd_info* __init crisv32_nand_flash_probe (void);
 257 static struct mtd_info *flash_probe(void)
 258 {
 259         struct mtd_info *mtd_cse0;
 260         struct mtd_info *mtd_cse1;
 261         struct mtd_info *mtd_total;
 262         struct mtd_info *mtds[2];
 263         int count = 0;
 264
 265         if ((mtd_cse0 = probe_cs(&map_cse0)) != NULL)
 266                 mtds[count++] = mtd_cse0;
 267         if ((mtd_cse1 = probe_cs(&map_cse1)) != NULL)
 268                 mtds[count++] = mtd_cse1;
 269
 270         if (!mtd_cse0 && !mtd_cse1) {
 271                 /* No chip found. */
 272                 return NULL;
 273         }
 274
 275         if (count > 1) {
 276                 /* Since the concatenation layer adds a small overhead we
 277                  * could try to figure out if the chips in cse0 and cse1 are
 278                  * identical and reprobe the whole cse0+cse1 window. But since
 279                  * flash chips are slow, the overhead is relatively small.
 280                  * So we use the MTD concatenation layer instead of further
 281                  * complicating the probing procedure.
 282                  */
 283                 mtd_total = mtd_concat_create(mtds, count, "cse0+cse1");
 284                 if (!mtd_total) {
 285                         printk(KERN_ERR "%s and %s: Concatenation failed!\n",
 286                                 map_cse0.name, map_cse1.name);
 287
 288                         /* The best we can do now is to only use what we found
 289                          * at cse0. */
 290                         mtd_total = mtd_cse0;
 291                         map_destroy(mtd_cse1);
 292                 }
 293         } else
 294                 mtd_total = mtd_cse0 ? mtd_cse0 : mtd_cse1;
 295
 296         return mtd_total;
 297 }
 298
 299 /*
 300  * Probe the flash chip(s) and, if it succeeds, read the partition-table
 301  * and register the partitions with MTD.
 302  */
 303 static int __init init_axis_flash(void)
 304 {
 305         struct mtd_info *main_mtd;
 306         struct mtd_info *aux_mtd = NULL;
 307         int err = 0;
 308         int pidx = 0;
 309         struct partitiontable_head *ptable_head = NULL;
 310         struct partitiontable_entry *ptable;
 311         int ptable_ok = 0;
 312         static char page[PAGESIZE];
 313         size_t len;
 314         int ram_rootfs_partition = -1; /* -1 => no RAM rootfs partition */
 315         int part;
 316         struct mtd_partition *partition;
 317
 318         /* We need a root fs. If it resides in RAM, we need to use an
 319          * MTDRAM device, so it must be enabled in the kernel config,
 320          * but its size must be configured as 0 so as not to conflict
 321          * with our usage.
 322          */
 323 #if !defined(CONFIG_MTD_MTDRAM) || (CONFIG_MTDRAM_TOTAL_SIZE != 0) || (CONFIG_MTDRAM_ABS_POS != 0)
 324         if (!romfs_in_flash && !nand_boot) {
 325                 printk(KERN_EMERG "axisflashmap: Cannot create an MTD RAM "
 326                        "device; configure CONFIG_MTD_MTDRAM with size = 0!\n");
 327                 panic("This kernel cannot boot from RAM!\n");
 328         }
 329 #endif
 330
 331         main_mtd = flash_probe();
 332         if (main_mtd)
 333                 printk(KERN_INFO "%s: 0x%08llx bytes of NOR flash memory.\n",
 334                        main_mtd->name, main_mtd->size);
 335
 336 #ifdef CONFIG_ETRAX_NANDFLASH
 337         aux_mtd = crisv32_nand_flash_probe();
 338         if (aux_mtd)
 339                 printk(KERN_INFO "%s: 0x%08x bytes of NAND flash memory.\n",
 340                         aux_mtd->name, aux_mtd->size);
 341
 342 #ifdef CONFIG_ETRAX_NANDBOOT
 343         {
 344                 struct mtd_info *tmp_mtd;
 345
 346                 printk(KERN_INFO "axisflashmap: Set to boot from NAND flash, "
 347                        "making NAND flash primary device.\n");
 348                 tmp_mtd = main_mtd;
 349                 main_mtd = aux_mtd;
 350                 aux_mtd = tmp_mtd;
 351         }
 352 #endif /* CONFIG_ETRAX_NANDBOOT */
 353 #endif /* CONFIG_ETRAX_NANDFLASH */
 354
 355         if (!main_mtd && !aux_mtd) {
 356                 /* There's no reason to use this module if no flash chip can
 357                  * be identified. Make sure that's understood.
 358                  */
 359                 printk(KERN_INFO "axisflashmap: Found no flash chip.\n");
 360         }
 361
 362 #if 0 /* Dump flash memory so we can see what is going on */
 363         if (main_mtd) {
 364                 int sectoraddr;
 365                 for (sectoraddr = 0; sectoraddr < 2*65536+4096;
 366                                 sectoraddr += PAGESIZE) {
 367                         main_mtd->read(main_mtd, sectoraddr, PAGESIZE, &len,
 368                                 page);
 369                         printk(KERN_INFO
 370                                "Sector at %d (length %d):\n",
 371                                sectoraddr, len);
 372                         print_hex_dump(KERN_INFO, "", DUMP_PREFIX_NONE, 16, 1, page, PAGESIZE, false);
 373                 }
 374         }
 375 #endif
 376
 377         if (main_mtd) {
 378                 loff_t ptable_sector = CONFIG_ETRAX_PTABLE_SECTOR;
 379                 main_mtd->owner = THIS_MODULE;
 380                 axisflash_mtd = main_mtd;
 381
 382
 383                 /* First partition (rescue) is always set to the default. */
 384                 pidx++;
 385 #ifdef CONFIG_ETRAX_NANDBOOT
 386                 /* We know where the partition table should be located,
 387                  * it will be in first good block after that.
 388                  */
 389                 int blockstat;
 390                 do {
 391                         blockstat = mtd_block_isbad(main_mtd, ptable_sector);
 392                         if (blockstat < 0)
 393                                 ptable_sector = 0; /* read error */
 394                         else if (blockstat)
 395                                 ptable_sector += main_mtd->erasesize;
 396                 } while (blockstat && ptable_sector);
 397 #endif
 398                 if (ptable_sector) {
 399                         mtd_read(main_mtd, ptable_sector, PAGESIZE, &len,
 400                                  page);
 401                         ptable_head = &((struct partitiontable *) page)->head;
 402                 }
 403
 404 #if 0 /* Dump partition table so we can see what is going on */
 405                 printk(KERN_INFO
 406                        "axisflashmap: flash read %d bytes at 0x%08x, data: %8ph\n",
 407                        len, CONFIG_ETRAX_PTABLE_SECTOR, page);
 408                 printk(KERN_INFO
 409                        "axisflashmap: partition table offset %d, data: %8ph\n",
 410                        PARTITION_TABLE_OFFSET, page + PARTITION_TABLE_OFFSET);
 411 #endif
 412         }
 413
 414         if (ptable_head && (ptable_head->magic == PARTITION_TABLE_MAGIC)
 415             && (ptable_head->size <
 416                 (MAX_PARTITIONS * sizeof(struct partitiontable_entry) +
 417                 PARTITIONTABLE_END_MARKER_SIZE))
 418             && (*(unsigned long*)((void*)ptable_head + sizeof(*ptable_head) +
 419                                   ptable_head->size -
 420                                   PARTITIONTABLE_END_MARKER_SIZE)
 421                 == PARTITIONTABLE_END_MARKER)) {
 422                 /* Looks like a start, sane length and end of a
 423                  * partition table, lets check csum etc.
 424                  */
 425                 struct partitiontable_entry *max_addr =
 426                         (struct partitiontable_entry *)
 427                         ((unsigned long)ptable_head + sizeof(*ptable_head) +
 428                          ptable_head->size);
 429                 unsigned long offset = CONFIG_ETRAX_PTABLE_SECTOR;
 430                 unsigned char *p;
 431                 unsigned long csum = 0;
 432
 433                 ptable = (struct partitiontable_entry *)
 434                         ((unsigned long)ptable_head + sizeof(*ptable_head));
 435
 436                 /* Lets be PARANOID, and check the checksum. */
 437                 p = (unsigned char*) ptable;
 438
 439                 while (p <= (unsigned char*)max_addr) {
 440                         csum += *p++;
 441                         csum += *p++;
 442                         csum += *p++;
 443                         csum += *p++;
 444                 }
 445                 ptable_ok = (csum == ptable_head->checksum);
 446
 447                 /* Read the entries and use/show the info.  */
 448                 printk(KERN_INFO "axisflashmap: "
 449                        "Found a%s partition table at 0x%p-0x%p.\n",
 450                        (ptable_ok ? " valid" : "n invalid"), ptable_head,
 451                        max_addr);
 452
 453                 /* We have found a working bootblock.  Now read the
 454                  * partition table.  Scan the table.  It ends with 0xffffffff.
 455                  */
 456                 while (ptable_ok
 457                        && ptable->offset != PARTITIONTABLE_END_MARKER
 458                        && ptable < max_addr
 459                        && pidx < MAX_PARTITIONS - 1) {
 460
 461                         axis_partitions[pidx].offset = offset + ptable->offset;
 462 #ifdef CONFIG_ETRAX_NANDFLASH
 463                         if (main_mtd->type == MTD_NANDFLASH) {
 464                                 axis_partitions[pidx].size =
 465                                         (((ptable+1)->offset ==
 466                                           PARTITIONTABLE_END_MARKER) ?
 467                                           main_mtd->size :
 468                                           ((ptable+1)->offset + offset)) -
 469                                         (ptable->offset + offset);
 470
 471                         } else
 472 #endif /* CONFIG_ETRAX_NANDFLASH */
 473                                 axis_partitions[pidx].size = ptable->size;
 474 #ifdef CONFIG_ETRAX_NANDBOOT
 475                         /* Save partition number of jffs2 ro partition.
 476                          * Needed if RAM booting or root file system in RAM.
 477                          */
 478                         if (!nand_boot &&
 479                             ram_rootfs_partition < 0 && /* not already set */
 480                             ptable->type == PARTITION_TYPE_JFFS2 &&
 481                             (ptable->flags & PARTITION_FLAGS_READONLY_MASK) ==
 482                                 PARTITION_FLAGS_READONLY)
 483                                 ram_rootfs_partition = pidx;
 484 #endif /* CONFIG_ETRAX_NANDBOOT */
 485                         pidx++;
 486                         ptable++;
 487                 }
 488         }
 489
 490         /* Decide whether to use default partition table. */
 491         /* Only use default table if we actually have a device (main_mtd) */
 492
 493         partition = &axis_partitions[0];
 494         if (main_mtd && !ptable_ok) {
 495                 memcpy(axis_partitions, axis_default_partitions,
 496                        sizeof(axis_default_partitions));
 497                 pidx = NUM_DEFAULT_PARTITIONS;
 498                 ram_rootfs_partition = DEFAULT_ROOTFS_PARTITION_NO;
 499         }
 500
 501         /* Add artificial partitions for rootfs if necessary */
 502         if (romfs_in_flash) {
 503                 /* rootfs is in directly accessible flash memory = NOR flash.
 504                    Add an overlapping device for the rootfs partition. */
 505                 printk(KERN_INFO "axisflashmap: Adding partition for "
 506                        "overlapping root file system image\n");
 507                 axis_partitions[pidx].size = romfs_length;
 508                 axis_partitions[pidx].offset = romfs_start - FLASH_CACHED_ADDR;
 509                 axis_partitions[pidx].name = "romfs";
 510                 axis_partitions[pidx].mask_flags |= MTD_WRITEABLE;
 511                 ram_rootfs_partition = -1;
 512                 pidx++;
 513         } else if (romfs_length && !nand_boot) {
 514                 /* romfs exists in memory, but not in flash, so must be in RAM.
 515                  * Configure an MTDRAM partition. */
 516                 if (ram_rootfs_partition < 0) {
 517                         /* None set yet, put it at the end */
 518                         ram_rootfs_partition = pidx;
 519                         pidx++;
 520                 }
 521                 printk(KERN_INFO "axisflashmap: Adding partition for "
 522                        "root file system image in RAM\n");
 523                 axis_partitions[ram_rootfs_partition].size = romfs_length;
 524                 axis_partitions[ram_rootfs_partition].offset = romfs_start;
 525                 axis_partitions[ram_rootfs_partition].name = "romfs";
 526                 axis_partitions[ram_rootfs_partition].mask_flags |=
 527                         MTD_WRITEABLE;
 528         }
 529
 530 #ifdef CONFIG_ETRAX_AXISFLASHMAP_MTD0WHOLE
 531         if (main_mtd) {
 532                 main_partition.size = main_mtd->size;
 533                 err = mtd_device_register(main_mtd, &main_partition, 1);
 534                 if (err)
 535                         panic("axisflashmap: Could not initialize "
 536                               "partition for whole main mtd device!\n");
 537         }
 538 #endif
 539
 540         /* Now, register all partitions with mtd.
 541          * We do this one at a time so we can slip in an MTDRAM device
 542          * in the proper place if required. */
 543
 544         for (part = 0; part < pidx; part++) {
 545                 if (part == ram_rootfs_partition) {
 546                         /* add MTDRAM partition here */
 547                         struct mtd_info *mtd_ram;
 548
 549                         mtd_ram = kmalloc(sizeof(struct mtd_info), GFP_KERNEL);
 550                         if (!mtd_ram)
 551                                 panic("axisflashmap: Couldn't allocate memory "
 552                                       "for mtd_info!\n");
 553                         printk(KERN_INFO "axisflashmap: Adding RAM partition "
 554                                "for rootfs image.\n");
 555                         err = mtdram_init_device(mtd_ram,
 556                                                  (void *)(u_int32_t)partition[part].offset,
 557                                                  partition[part].size,
 558                                                  partition[part].name);
 559                         if (err)
 560                                 panic("axisflashmap: Could not initialize "
 561                                       "MTD RAM device!\n");
 562                         /* JFFS2 likes to have an erasesize. Keep potential
 563                          * JFFS2 rootfs happy by providing one. Since image
 564                          * was most likely created for main mtd, use that
 565                          * erasesize, if available. Otherwise, make a guess. */
 566                         mtd_ram->erasesize = (main_mtd ? main_mtd->erasesize :
 567                                 CONFIG_ETRAX_PTABLE_SECTOR);
 568                 } else {
 569                         err = mtd_device_register(main_mtd, &partition[part],
 570                                                   1);
 571                         if (err)
 572                                 panic("axisflashmap: Could not add mtd "
 573                                         "partition %d\n", part);
 574                 }
 575         }
 576
 577         if (aux_mtd) {
 578                 aux_partition.size = aux_mtd->size;
 579                 err = mtd_device_register(aux_mtd, &aux_partition, 1);
 580                 if (err)
 581                         panic("axisflashmap: Could not initialize "
 582                               "aux mtd device!\n");
 583
 584         }
 585
 586         return err;
 587 }
 588
 589 /* This adds the above to the kernels init-call chain. */
 590 module_init(init_axis_flash);
 591
 592 EXPORT_SYMBOL(axisflash_mtd);