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 <linux/cramfs_fs.h>
  28
  29 #include <asm/axisflashmap.h>
  30 #include <asm/mmu.h>
  31
  32 #define MEM_CSE0_SIZE (0x04000000)
  33 #define MEM_CSE1_SIZE (0x04000000)
  34
  35 #define FLASH_UNCACHED_ADDR  KSEG_E
  36 #define FLASH_CACHED_ADDR    KSEG_F
  37
  38 #define PAGESIZE (512)
  39
  40 #if CONFIG_ETRAX_FLASH_BUSWIDTH==1
  41 #define flash_data __u8
  42 #elif CONFIG_ETRAX_FLASH_BUSWIDTH==2
  43 #define flash_data __u16
  44 #elif CONFIG_ETRAX_FLASH_BUSWIDTH==4
  45 #define flash_data __u32
  46 #endif
  47
  48 /* From head.S */
  49 extern unsigned long romfs_in_flash; /* 1 when romfs_start, _length in flash */
  50 extern unsigned long romfs_start, romfs_length;
  51 extern unsigned long nand_boot; /* 1 when booted from nand flash */
  52
  53 struct partition_name {
  54         char name[6];
  55 };
  56
  57 /* The master mtd for the entire flash. */
  58 struct mtd_info* axisflash_mtd = NULL;
  59
  60 /* Map driver functions. */
  61
  62 static map_word flash_read(struct map_info *map, unsigned long ofs)
  63 {
  64         map_word tmp;
  65         tmp.x[0] = *(flash_data *)(map->map_priv_1 + ofs);
  66         return tmp;
  67 }
  68
  69 static void flash_copy_from(struct map_info *map, void *to,
  70                             unsigned long from, ssize_t len)
  71 {
  72         memcpy(to, (void *)(map->map_priv_1 + from), len);
  73 }
  74
  75 static void flash_write(struct map_info *map, map_word d, unsigned long adr)
  76 {
  77         *(flash_data *)(map->map_priv_1 + adr) = (flash_data)d.x[0];
  78 }
  79
  80 /*
  81  * The map for chip select e0.
  82  *
  83  * We run into tricky coherence situations if we mix cached with uncached
  84  * accesses to we only use the uncached version here.
  85  *
  86  * The size field is the total size where the flash chips may be mapped on the
  87  * chip select. MTD probes should find all devices there and it does not matter
  88  * if there are unmapped gaps or aliases (mirrors of flash devices). The MTD
  89  * probes will ignore them.
  90  *
  91  * The start address in map_priv_1 is in virtual memory so we cannot use
  92  * MEM_CSE0_START but must rely on that FLASH_UNCACHED_ADDR is the start
  93  * address of cse0.
  94  */
  95 static struct map_info map_cse0 = {
  96         .name = "cse0",
  97         .size = MEM_CSE0_SIZE,
  98         .bankwidth = CONFIG_ETRAX_FLASH_BUSWIDTH,
  99         .read = flash_read,
 100         .copy_from = flash_copy_from,
 101         .write = flash_write,
 102         .map_priv_1 = FLASH_UNCACHED_ADDR
 103 };
 104
 105 /*
 106  * The map for chip select e1.
 107  *
 108  * If there was a gap between cse0 and cse1, map_priv_1 would get the wrong
 109  * address, but there isn't.
 110  */
 111 static struct map_info map_cse1 = {
 112         .name = "cse1",
 113         .size = MEM_CSE1_SIZE,
 114         .bankwidth = CONFIG_ETRAX_FLASH_BUSWIDTH,
 115         .read = flash_read,
 116         .copy_from = flash_copy_from,
 117         .write = flash_write,
 118         .map_priv_1 = FLASH_UNCACHED_ADDR + MEM_CSE0_SIZE
 119 };
 120
 121 #define MAX_PARTITIONS                  7
 122 #ifdef CONFIG_ETRAX_NANDBOOT
 123 #define NUM_DEFAULT_PARTITIONS          4
 124 #define DEFAULT_ROOTFS_PARTITION_NO     2
 125 #define DEFAULT_MEDIA_SIZE              0x2000000 /* 32 megs */
 126 #else
 127 #define NUM_DEFAULT_PARTITIONS          3
 128 #define DEFAULT_ROOTFS_PARTITION_NO     (-1)
 129 #define DEFAULT_MEDIA_SIZE              0x800000 /* 8 megs */
 130 #endif
 131
 132 #if (MAX_PARTITIONS < NUM_DEFAULT_PARTITIONS)
 133 #error MAX_PARTITIONS must be >= than NUM_DEFAULT_PARTITIONS
 134 #endif
 135
 136 /* Initialize the ones normally used. */
 137 static struct mtd_partition axis_partitions[MAX_PARTITIONS] = {
 138         {
 139                 .name = "part0",
 140                 .size = CONFIG_ETRAX_PTABLE_SECTOR,
 141                 .offset = 0
 142         },
 143         {
 144                 .name = "part1",
 145                 .size = 0,
 146                 .offset = 0
 147         },
 148         {
 149                 .name = "part2",
 150                 .size = 0,
 151                 .offset = 0
 152         },
 153         {
 154                 .name = "part3",
 155                 .size = 0,
 156                 .offset = 0
 157         },
 158         {
 159                 .name = "part4",
 160                 .size = 0,
 161                 .offset = 0
 162         },
 163         {
 164                 .name = "part5",
 165                 .size = 0,
 166                 .offset = 0
 167         },
 168         {
 169                 .name = "part6",
 170                 .size = 0,
 171                 .offset = 0
 172         },
 173 };
 174
 175
 176 /* If no partition-table was found, we use this default-set.
 177  * Default flash size is 8MB (NOR). CONFIG_ETRAX_PTABLE_SECTOR is most
 178  * likely the size of one flash block and "filesystem"-partition needs
 179  * to be >=5 blocks to be able to use JFFS.
 180  */
 181 static struct mtd_partition axis_default_partitions[NUM_DEFAULT_PARTITIONS] = {
 182         {
 183                 .name = "boot firmware",
 184                 .size = CONFIG_ETRAX_PTABLE_SECTOR,
 185                 .offset = 0
 186         },
 187         {
 188                 .name = "kernel",
 189                 .size = 10 * CONFIG_ETRAX_PTABLE_SECTOR,
 190                 .offset = CONFIG_ETRAX_PTABLE_SECTOR
 191         },
 192 #define FILESYSTEM_SECTOR (11 * CONFIG_ETRAX_PTABLE_SECTOR)
 193 #ifdef CONFIG_ETRAX_NANDBOOT
 194         {
 195                 .name = "rootfs",
 196                 .size = 10 * CONFIG_ETRAX_PTABLE_SECTOR,
 197                 .offset = FILESYSTEM_SECTOR
 198         },
 199 #undef FILESYSTEM_SECTOR
 200 #define FILESYSTEM_SECTOR (21 * CONFIG_ETRAX_PTABLE_SECTOR)
 201 #endif
 202         {
 203                 .name = "rwfs",
 204                 .size = DEFAULT_MEDIA_SIZE - FILESYSTEM_SECTOR,
 205                 .offset = FILESYSTEM_SECTOR
 206         }
 207 };
 208
 209 #ifdef CONFIG_ETRAX_AXISFLASHMAP_MTD0WHOLE
 210 /* Main flash device */
 211 static struct mtd_partition main_partition = {
 212         .name = "main",
 213         .size = 0,
 214         .offset = 0
 215 };
 216 #endif
 217
 218 /* Auxiliary partition if we find another flash */
 219 static struct mtd_partition aux_partition = {
 220         .name = "aux",
 221         .size = 0,
 222         .offset = 0
 223 };
 224
 225 /*
 226  * Probe a chip select for AMD-compatible (JEDEC) or CFI-compatible flash
 227  * chips in that order (because the amd_flash-driver is faster).
 228  */
 229 static struct mtd_info *probe_cs(struct map_info *map_cs)
 230 {
 231         struct mtd_info *mtd_cs = NULL;
 232
 233         printk(KERN_INFO
 234                "%s: Probing a 0x%08lx bytes large window at 0x%08lx.\n",
 235                map_cs->name, map_cs->size, map_cs->map_priv_1);
 236
 237 #ifdef CONFIG_MTD_CFI
 238         mtd_cs = do_map_probe("cfi_probe", map_cs);
 239 #endif
 240 #ifdef CONFIG_MTD_JEDECPROBE
 241         if (!mtd_cs)
 242                 mtd_cs = do_map_probe("jedec_probe", map_cs);
 243 #endif
 244
 245         return mtd_cs;
 246 }
 247
 248 /*
 249  * Probe each chip select individually for flash chips. If there are chips on
 250  * both cse0 and cse1, the mtd_info structs will be concatenated to one struct
 251  * so that MTD partitions can cross chip boundries.
 252  *
 253  * The only known restriction to how you can mount your chips is that each
 254  * chip select must hold similar flash chips. But you need external hardware
 255  * to do that anyway and you can put totally different chips on cse0 and cse1
 256  * so it isn't really much of a restriction.
 257  */
 258 extern struct mtd_info* __init crisv32_nand_flash_probe (void);
 259 static struct mtd_info *flash_probe(void)
 260 {
 261         struct mtd_info *mtd_cse0;
 262         struct mtd_info *mtd_cse1;
 263         struct mtd_info *mtd_total;
 264         struct mtd_info *mtds[2];
 265         int count = 0;
 266
 267         if ((mtd_cse0 = probe_cs(&map_cse0)) != NULL)
 268                 mtds[count++] = mtd_cse0;
 269         if ((mtd_cse1 = probe_cs(&map_cse1)) != NULL)
 270                 mtds[count++] = mtd_cse1;
 271
 272         if (!mtd_cse0 && !mtd_cse1) {
 273                 /* No chip found. */
 274                 return NULL;
 275         }
 276
 277         if (count > 1) {
 278                 /* Since the concatenation layer adds a small overhead we
 279                  * could try to figure out if the chips in cse0 and cse1 are
 280                  * identical and reprobe the whole cse0+cse1 window. But since
 281                  * flash chips are slow, the overhead is relatively small.
 282                  * So we use the MTD concatenation layer instead of further
 283                  * complicating the probing procedure.
 284                  */
 285                 mtd_total = mtd_concat_create(mtds, count, "cse0+cse1");
 286                 if (!mtd_total) {
 287                         printk(KERN_ERR "%s and %s: Concatenation failed!\n",
 288                                 map_cse0.name, map_cse1.name);
 289
 290                         /* The best we can do now is to only use what we found
 291                          * at cse0. */
 292                         mtd_total = mtd_cse0;
 293                         map_destroy(mtd_cse1);
 294                 }
 295         } else
 296                 mtd_total = mtd_cse0 ? mtd_cse0 : mtd_cse1;
 297
 298         return mtd_total;
 299 }
 300
 301 /*
 302  * Probe the flash chip(s) and, if it succeeds, read the partition-table
 303  * and register the partitions with MTD.
 304  */
 305 static int __init init_axis_flash(void)
 306 {
 307         struct mtd_info *main_mtd;
 308         struct mtd_info *aux_mtd = NULL;
 309         int err = 0;
 310         int pidx = 0;
 311         struct partitiontable_head *ptable_head = NULL;
 312         struct partitiontable_entry *ptable;
 313         int ptable_ok = 0;
 314         static char page[PAGESIZE];
 315         size_t len;
 316         int ram_rootfs_partition = -1; /* -1 => no RAM rootfs partition */
 317         int part;
 318
 319         /* We need a root fs. If it resides in RAM, we need to use an
 320          * MTDRAM device, so it must be enabled in the kernel config,
 321          * but its size must be configured as 0 so as not to conflict
 322          * with our usage.
 323          */
 324 #if !defined(CONFIG_MTD_MTDRAM) || (CONFIG_MTDRAM_TOTAL_SIZE != 0) || (CONFIG_MTDRAM_ABS_POS != 0)
 325         if (!romfs_in_flash && !nand_boot) {
 326                 printk(KERN_EMERG "axisflashmap: Cannot create an MTD RAM "
 327                        "device; configure CONFIG_MTD_MTDRAM with size = 0!\n");
 328                 panic("This kernel cannot boot from RAM!\n");
 329         }
 330 #endif
 331
 332         main_mtd = flash_probe();
 333         if (main_mtd)
 334                 printk(KERN_INFO "%s: 0x%08x bytes of NOR flash memory.\n",
 335                        main_mtd->name, main_mtd->size);
 336
 337 #ifdef CONFIG_ETRAX_NANDFLASH
 338         aux_mtd = crisv32_nand_flash_probe();
 339         if (aux_mtd)
 340                 printk(KERN_INFO "%s: 0x%08x bytes of NAND flash memory.\n",
 341                         aux_mtd->name, aux_mtd->size);
 342
 343 #ifdef CONFIG_ETRAX_NANDBOOT
 344         {
 345                 struct mtd_info *tmp_mtd;
 346
 347                 printk(KERN_INFO "axisflashmap: Set to boot from NAND flash, "
 348                        "making NAND flash primary device.\n");
 349                 tmp_mtd = main_mtd;
 350                 main_mtd = aux_mtd;
 351                 aux_mtd = tmp_mtd;
 352         }
 353 #endif /* CONFIG_ETRAX_NANDBOOT */
 354 #endif /* CONFIG_ETRAX_NANDFLASH */
 355
 356         if (!main_mtd && !aux_mtd) {
 357                 /* There's no reason to use this module if no flash chip can
 358                  * be identified. Make sure that's understood.
 359                  */
 360                 printk(KERN_INFO "axisflashmap: Found no flash chip.\n");
 361         }
 362
 363 #if 0 /* Dump flash memory so we can see what is going on */
 364         if (main_mtd) {
 365                 int sectoraddr, i;
 366                 for (sectoraddr = 0; sectoraddr < 2*65536+4096;
 367                                 sectoraddr += PAGESIZE) {
 368                         main_mtd->read(main_mtd, sectoraddr, PAGESIZE, &len,
 369                                 page);
 370                         printk(KERN_INFO
 371                                "Sector at %d (length %d):\n",
 372                                sectoraddr, len);
 373                         for (i = 0; i < PAGESIZE; i += 16) {
 374                                 printk(KERN_INFO
 375                                        "%02x %02x %02x %02x "
 376                                        "%02x %02x %02x %02x "
 377                                        "%02x %02x %02x %02x "
 378                                        "%02x %02x %02x %02x\n",
 379                                        page[i] & 255, page[i+1] & 255,
 380                                        page[i+2] & 255, page[i+3] & 255,
 381                                        page[i+4] & 255, page[i+5] & 255,
 382                                        page[i+6] & 255, page[i+7] & 255,
 383                                        page[i+8] & 255, page[i+9] & 255,
 384                                        page[i+10] & 255, page[i+11] & 255,
 385                                        page[i+12] & 255, page[i+13] & 255,
 386                                        page[i+14] & 255, page[i+15] & 255);
 387                         }
 388                 }
 389         }
 390 #endif
 391
 392         if (main_mtd) {
 393                 main_mtd->owner = THIS_MODULE;
 394                 axisflash_mtd = main_mtd;
 395
 396                 loff_t ptable_sector = CONFIG_ETRAX_PTABLE_SECTOR;
 397
 398                 /* First partition (rescue) is always set to the default. */
 399                 pidx++;
 400 #ifdef CONFIG_ETRAX_NANDBOOT
 401                 /* We know where the partition table should be located,
 402                  * it will be in first good block after that.
 403                  */
 404                 int blockstat;
 405                 do {
 406                         blockstat = mtd_block_isbad(main_mtd, ptable_sector);
 407                         if (blockstat < 0)
 408                                 ptable_sector = 0; /* read error */
 409                         else if (blockstat)
 410                                 ptable_sector += main_mtd->erasesize;
 411                 } while (blockstat && ptable_sector);
 412 #endif
 413                 if (ptable_sector) {
 414                         mtd_read(main_mtd, ptable_sector, PAGESIZE, &len,
 415                                  page);
 416                         ptable_head = &((struct partitiontable *) page)->head;
 417                 }
 418
 419 #if 0 /* Dump partition table so we can see what is going on */
 420                 printk(KERN_INFO
 421                        "axisflashmap: flash read %d bytes at 0x%08x, data: "
 422                        "%02x %02x %02x %02x %02x %02x %02x %02x\n",
 423                        len, CONFIG_ETRAX_PTABLE_SECTOR,
 424                        page[0] & 255, page[1] & 255,
 425                        page[2] & 255, page[3] & 255,
 426                        page[4] & 255, page[5] & 255,
 427                        page[6] & 255, page[7] & 255);
 428                 printk(KERN_INFO
 429                        "axisflashmap: partition table offset %d, data: "
 430                        "%02x %02x %02x %02x %02x %02x %02x %02x\n",
 431                        PARTITION_TABLE_OFFSET,
 432                        page[PARTITION_TABLE_OFFSET+0] & 255,
 433                        page[PARTITION_TABLE_OFFSET+1] & 255,
 434                        page[PARTITION_TABLE_OFFSET+2] & 255,
 435                        page[PARTITION_TABLE_OFFSET+3] & 255,
 436                        page[PARTITION_TABLE_OFFSET+4] & 255,
 437                        page[PARTITION_TABLE_OFFSET+5] & 255,
 438                        page[PARTITION_TABLE_OFFSET+6] & 255,
 439                        page[PARTITION_TABLE_OFFSET+7] & 255);
 440 #endif
 441         }
 442
 443         if (ptable_head && (ptable_head->magic == PARTITION_TABLE_MAGIC)
 444             && (ptable_head->size <
 445                 (MAX_PARTITIONS * sizeof(struct partitiontable_entry) +
 446                 PARTITIONTABLE_END_MARKER_SIZE))
 447             && (*(unsigned long*)((void*)ptable_head + sizeof(*ptable_head) +
 448                                   ptable_head->size -
 449                                   PARTITIONTABLE_END_MARKER_SIZE)
 450                 == PARTITIONTABLE_END_MARKER)) {
 451                 /* Looks like a start, sane length and end of a
 452                  * partition table, lets check csum etc.
 453                  */
 454                 struct partitiontable_entry *max_addr =
 455                         (struct partitiontable_entry *)
 456                         ((unsigned long)ptable_head + sizeof(*ptable_head) +
 457                          ptable_head->size);
 458                 unsigned long offset = CONFIG_ETRAX_PTABLE_SECTOR;
 459                 unsigned char *p;
 460                 unsigned long csum = 0;
 461
 462                 ptable = (struct partitiontable_entry *)
 463                         ((unsigned long)ptable_head + sizeof(*ptable_head));
 464
 465                 /* Lets be PARANOID, and check the checksum. */
 466                 p = (unsigned char*) ptable;
 467
 468                 while (p <= (unsigned char*)max_addr) {
 469                         csum += *p++;
 470                         csum += *p++;
 471                         csum += *p++;
 472                         csum += *p++;
 473                 }
 474                 ptable_ok = (csum == ptable_head->checksum);
 475
 476                 /* Read the entries and use/show the info.  */
 477                 printk(KERN_INFO "axisflashmap: "
 478                        "Found a%s partition table at 0x%p-0x%p.\n",
 479                        (ptable_ok ? " valid" : "n invalid"), ptable_head,
 480                        max_addr);
 481
 482                 /* We have found a working bootblock.  Now read the
 483                  * partition table.  Scan the table.  It ends with 0xffffffff.
 484                  */
 485                 while (ptable_ok
 486                        && ptable->offset != PARTITIONTABLE_END_MARKER
 487                        && ptable < max_addr
 488                        && pidx < MAX_PARTITIONS - 1) {
 489
 490                         axis_partitions[pidx].offset = offset + ptable->offset;
 491 #ifdef CONFIG_ETRAX_NANDFLASH
 492                         if (main_mtd->type == MTD_NANDFLASH) {
 493                                 axis_partitions[pidx].size =
 494                                         (((ptable+1)->offset ==
 495                                           PARTITIONTABLE_END_MARKER) ?
 496                                           main_mtd->size :
 497                                           ((ptable+1)->offset + offset)) -
 498                                         (ptable->offset + offset);
 499
 500                         } else
 501 #endif /* CONFIG_ETRAX_NANDFLASH */
 502                                 axis_partitions[pidx].size = ptable->size;
 503 #ifdef CONFIG_ETRAX_NANDBOOT
 504                         /* Save partition number of jffs2 ro partition.
 505                          * Needed if RAM booting or root file system in RAM.
 506                          */
 507                         if (!nand_boot &&
 508                             ram_rootfs_partition < 0 && /* not already set */
 509                             ptable->type == PARTITION_TYPE_JFFS2 &&
 510                             (ptable->flags & PARTITION_FLAGS_READONLY_MASK) ==
 511                                 PARTITION_FLAGS_READONLY)
 512                                 ram_rootfs_partition = pidx;
 513 #endif /* CONFIG_ETRAX_NANDBOOT */
 514                         pidx++;
 515                         ptable++;
 516                 }
 517         }
 518
 519         /* Decide whether to use default partition table. */
 520         /* Only use default table if we actually have a device (main_mtd) */
 521
 522         struct mtd_partition *partition = &axis_partitions[0];
 523         if (main_mtd && !ptable_ok) {
 524                 memcpy(axis_partitions, axis_default_partitions,
 525                        sizeof(axis_default_partitions));
 526                 pidx = NUM_DEFAULT_PARTITIONS;
 527                 ram_rootfs_partition = DEFAULT_ROOTFS_PARTITION_NO;
 528         }
 529
 530         /* Add artificial partitions for rootfs if necessary */
 531         if (romfs_in_flash) {
 532                 /* rootfs is in directly accessible flash memory = NOR flash.
 533                    Add an overlapping device for the rootfs partition. */
 534                 printk(KERN_INFO "axisflashmap: Adding partition for "
 535                        "overlapping root file system image\n");
 536                 axis_partitions[pidx].size = romfs_length;
 537                 axis_partitions[pidx].offset = romfs_start - FLASH_CACHED_ADDR;
 538                 axis_partitions[pidx].name = "romfs";
 539                 axis_partitions[pidx].mask_flags |= MTD_WRITEABLE;
 540                 ram_rootfs_partition = -1;
 541                 pidx++;
 542         } else if (romfs_length && !nand_boot) {
 543                 /* romfs exists in memory, but not in flash, so must be in RAM.
 544                  * Configure an MTDRAM partition. */
 545                 if (ram_rootfs_partition < 0) {
 546                         /* None set yet, put it at the end */
 547                         ram_rootfs_partition = pidx;
 548                         pidx++;
 549                 }
 550                 printk(KERN_INFO "axisflashmap: Adding partition for "
 551                        "root file system image in RAM\n");
 552                 axis_partitions[ram_rootfs_partition].size = romfs_length;
 553                 axis_partitions[ram_rootfs_partition].offset = romfs_start;
 554                 axis_partitions[ram_rootfs_partition].name = "romfs";
 555                 axis_partitions[ram_rootfs_partition].mask_flags |=
 556                         MTD_WRITEABLE;
 557         }
 558
 559 #ifdef CONFIG_ETRAX_AXISFLASHMAP_MTD0WHOLE
 560         if (main_mtd) {
 561                 main_partition.size = main_mtd->size;
 562                 err = mtd_device_register(main_mtd, &main_partition, 1);
 563                 if (err)
 564                         panic("axisflashmap: Could not initialize "
 565                               "partition for whole main mtd device!\n");
 566         }
 567 #endif
 568
 569         /* Now, register all partitions with mtd.
 570          * We do this one at a time so we can slip in an MTDRAM device
 571          * in the proper place if required. */
 572
 573         for (part = 0; part < pidx; part++) {
 574                 if (part == ram_rootfs_partition) {
 575                         /* add MTDRAM partition here */
 576                         struct mtd_info *mtd_ram;
 577
 578                         mtd_ram = kmalloc(sizeof(struct mtd_info), GFP_KERNEL);
 579                         if (!mtd_ram)
 580                                 panic("axisflashmap: Couldn't allocate memory "
 581                                       "for mtd_info!\n");
 582                         printk(KERN_INFO "axisflashmap: Adding RAM partition "
 583                                "for rootfs image.\n");
 584                         err = mtdram_init_device(mtd_ram,
 585                                                  (void *)partition[part].offset,
 586                                                  partition[part].size,
 587                                                  partition[part].name);
 588                         if (err)
 589                                 panic("axisflashmap: Could not initialize "
 590                                       "MTD RAM device!\n");
 591                         /* JFFS2 likes to have an erasesize. Keep potential
 592                          * JFFS2 rootfs happy by providing one. Since image
 593                          * was most likely created for main mtd, use that
 594                          * erasesize, if available. Otherwise, make a guess. */
 595                         mtd_ram->erasesize = (main_mtd ? main_mtd->erasesize :
 596                                 CONFIG_ETRAX_PTABLE_SECTOR);
 597                 } else {
 598                         err = mtd_device_register(main_mtd, &partition[part],
 599                                                   1);
 600                         if (err)
 601                                 panic("axisflashmap: Could not add mtd "
 602                                         "partition %d\n", part);
 603                 }
 604         }
 605
 606         if (aux_mtd) {
 607                 aux_partition.size = aux_mtd->size;
 608                 err = mtd_device_register(aux_mtd, &aux_partition, 1);
 609                 if (err)
 610                         panic("axisflashmap: Could not initialize "
 611                               "aux mtd device!\n");
 612
 613         }
 614
 615         return err;
 616 }
 617
 618 /* This adds the above to the kernels init-call chain. */
 619 module_init(init_axis_flash);
 620
 621 EXPORT_SYMBOL(axisflash_mtd);