target/linux/adm8668/files/drivers/mtd/maps/adm8668.c

   1 /*
   2  *  Copyright (C) 2010 Scott Nicholas <neutronscott@scottn.us>
   3  *  Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org>
   4  *  Copyright (C) 2005 Waldemar Brodkorb <wbx@openwrt.org>
   5  *  Copyright (C) 2004 Florian Schirmer (jolt@tuxbox.org)
   6  *
   7  *  original functions for finding root filesystem from Mike Baker
   8  *
   9  *  This program is free software; you can redistribute  it and/or modify it
  10  *  under  the terms of  the GNU General  Public License as published by the
  11  *  Free Software Foundation;  either version 2 of the  License, or (at your
  12  *  option) any later version.
  13  *
  14  *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
  15  *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
  16  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
  17  *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
  18  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  19  *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
  20  *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
  21  *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
  22  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  23  *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  *
  25  *  You should have received a copy of the  GNU General Public License along
  26  *  with this program; if not, write  to the Free Software Foundation, Inc.,
  27  *  675 Mass Ave, Cambridge, MA 02139, USA.
  28  *
  29  *
  30  * Copyright 2004, Broadcom Corporation
  31  * All Rights Reserved.
  32  *
  33  * THIS SOFTWARE IS OFFERED "AS IS", AND BROADCOM GRANTS NO WARRANTIES OF ANY
  34  * KIND, EXPRESS OR IMPLIED, BY STATUTE, COMMUNICATION OR OTHERWISE. BROADCOM
  35  * SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
  36  * FOR A SPECIFIC PURPOSE OR NONINFRINGEMENT CONCERNING THIS SOFTWARE.
  37  *
  38  * Flash mapping for adm8668 boards
  39  *
  40  */
  41
  42 #include <linux/module.h>
  43 #include <linux/types.h>
  44 #include <linux/kernel.h>
  45 #include <linux/sched.h>
  46 #include <linux/wait.h>
  47 #include <linux/mtd/mtd.h>
  48 #include <linux/mtd/map.h>
  49 #include <linux/slab.h>
  50 #include <linux/mtd/partitions.h>
  51 #include <linux/crc32.h>
  52 #include <linux/magic.h>
  53 #include <asm/io.h>
  54
  55 #define WINDOW_ADDR     0x10000000
  56 #define WINDOW_SIZE     0x800000
  57 #define BANKWIDTH       2
  58
  59 /* first a little bit about the headers i need.. */
  60
  61 /* just interested in part of the full struct */
  62 struct squashfs_super_block {
  63         __le32  s_magic;
  64         __le32  pad0[9];        /* it's not really padding */
  65         __le64  bytes_used;
  66 };
  67
  68 #define IH_MAGIC        0x56190527      /* Image Magic Number           */
  69 struct uboot_header {
  70         uint32_t        ih_magic;       /* Image Header Magic Number    */
  71         uint32_t        ih_hcrc;        /* Image Header CRC Checksum    */
  72         uint32_t        ih_time;        /* Image Creation Timestamp     */
  73         uint32_t        ih_size;        /* Image Data Size              */
  74         uint32_t        ih_load;        /* Data  Load  Address          */
  75         uint32_t        ih_ep;          /* Entry Point Address          */
  76         uint32_t        ih_dcrc;        /* Image Data CRC Checksum      */
  77         uint8_t         ih_os;          /* Operating System             */
  78         uint8_t         ih_arch;        /* CPU architecture             */
  79         uint8_t         ih_type;        /* Image Type                   */
  80         uint8_t         ih_comp;        /* Compression Type             */
  81         char            ih_name[32];    /* image name */
  82 };
  83
  84 /************************************************/
  85
  86 static struct mtd_info *adm8668_mtd;
  87
  88 struct map_info adm8668_map = {
  89         name: "adm8668-nor",
  90         size: WINDOW_SIZE,
  91         phys: WINDOW_ADDR,
  92         bankwidth: BANKWIDTH,
  93 };
  94
  95 /*
  96  * Copied from mtdblock.c
  97  *
  98  * Cache stuff...
  99  *
 100  * Since typical flash erasable sectors are much larger than what Linux's
 101  * buffer cache can handle, we must implement read-modify-write on flash
 102  * sectors for each block write requests.  To avoid over-erasing flash sectors
 103  * and to speed things up, we locally cache a whole flash sector while it is
 104  * being written to until a different sector is required.
 105  */
 106
 107 static void erase_callback(struct erase_info *done)
 108 {
 109         wait_queue_head_t *wait_q = (wait_queue_head_t *)done->priv;
 110         wake_up(wait_q);
 111 }
 112
 113 static int erase_write (struct mtd_info *mtd, unsigned long pos,
 114                         int len, const char *buf)
 115 {
 116         struct erase_info erase;
 117         DECLARE_WAITQUEUE(wait, current);
 118         wait_queue_head_t wait_q;
 119         size_t retlen;
 120         int ret;
 121
 122         /*
 123          * First, let's erase the flash block.
 124          */
 125
 126         init_waitqueue_head(&wait_q);
 127         erase.mtd = mtd;
 128         erase.callback = erase_callback;
 129         erase.addr = pos;
 130         erase.len = len;
 131         erase.priv = (u_long)&wait_q;
 132
 133         set_current_state(TASK_INTERRUPTIBLE);
 134         add_wait_queue(&wait_q, &wait);
 135
 136         ret = mtd->erase(mtd, &erase);
 137         if (ret) {
 138                 set_current_state(TASK_RUNNING);
 139                 remove_wait_queue(&wait_q, &wait);
 140                 printk (KERN_WARNING "erase of region [0x%lx, 0x%x] "
 141                                      "on \"%s\" failed\n",
 142                         pos, len, mtd->name);
 143                 return ret;
 144         }
 145
 146         schedule();  /* Wait for erase to finish. */
 147         remove_wait_queue(&wait_q, &wait);
 148
 149         /*
 150          * Next, write data to flash.
 151          */
 152
 153         ret = mtd->write (mtd, pos, len, &retlen, buf);
 154         if (ret)
 155                 return ret;
 156         if (retlen != len)
 157                 return -EIO;
 158         return 0;
 159 }
 160
 161 /* decent defaults in case... shrug */
 162 static struct mtd_partition adm8668_parts[] = {
 163         { name: "linux",        offset: 0x40000,        size: WINDOW_SIZE-0x40000, },
 164         { name: "rootfs",       offset: 0xe0000,        size: 0x140000, },
 165         { name: "uboot_env",    offset: 0x20000,        size: 0x20000, },
 166         { name: NULL, },
 167 };
 168
 169 /* in case i wanna change stuff later, and to clarify the math section... */
 170 #define PART_LINUX      0
 171 #define PART_ROOTFS     1
 172 #define NR_PARTS        3
 173
 174 static int __init
 175 init_mtd_partitions(struct mtd_info *mtd, size_t size)
 176 {
 177         struct uboot_header uhdr;
 178         int off, blocksize;
 179         size_t len, linux_len;
 180         struct squashfs_super_block shdr;
 181
 182         blocksize = mtd->erasesize;
 183         if (blocksize < 0x10000)
 184                 blocksize = 0x10000;
 185
 186         /* now find squashfs */
 187         memset(&shdr, 0xe5, sizeof(shdr));
 188         for (off = adm8668_parts[PART_LINUX].offset; off < size; off += blocksize) {
 189                 /*
 190                  * Read into buffer
 191                  */
 192                 if (mtd->read(mtd, off, sizeof(shdr), &len, (char *)&shdr) ||
 193                     len != sizeof(shdr))
 194                         continue;
 195
 196                 if (shdr.s_magic == SQUASHFS_MAGIC) {
 197                         uint32_t fs_size = (uint32_t)shdr.bytes_used;
 198
 199                         printk(KERN_INFO "%s: Filesystem type: squashfs, size=%dkB\n",
 200                                 mtd->name, fs_size>>10);
 201
 202                         /* Update rootfs based on the superblock info, and
 203                          * stretch to end of MTD. rootfs_split will split it */
 204                         adm8668_parts[PART_ROOTFS].offset = off;
 205                         adm8668_parts[PART_ROOTFS].size = mtd->size -
 206                                 adm8668_parts[PART_ROOTFS].offset;
 207
 208                         /* kernel ends where rootfs starts
 209                          * but we'll keep it full-length for upgrades */
 210                         linux_len = adm8668_parts[PART_LINUX+1].offset -
 211                                 adm8668_parts[PART_LINUX].offset;
 212 #if 1
 213                         adm8668_parts[PART_LINUX].size = mtd->size -
 214                                 adm8668_parts[PART_LINUX].offset;
 215 #else
 216                         adm8668_parts[PART_LINUX].size = linux_len;
 217 #endif
 218                         goto found;
 219                 }
 220         }
 221
 222         printk(KERN_NOTICE
 223                "%s: Couldn't find root filesystem\n",
 224                mtd->name);
 225         return NR_PARTS;
 226
 227  found:
 228         if (mtd->read(mtd, adm8668_parts[PART_LINUX].offset, sizeof(uhdr), &len, (char *)&uhdr) ||
 229             len != sizeof(uhdr))
 230                 return NR_PARTS;
 231
 232         /* that's odd. how'd ya boot it then */
 233         if (uhdr.ih_magic != IH_MAGIC)
 234                 return NR_PARTS;
 235
 236         if (be32_to_cpu(uhdr.ih_size) != (linux_len - sizeof(uhdr))) {
 237                 unsigned char *block, *data;
 238                 unsigned int offset;
 239
 240                 offset = adm8668_parts[PART_LINUX].offset +
 241                          sizeof(struct uboot_header);
 242                 data = (unsigned char *)(WINDOW_ADDR | 0xA0000000 | offset);
 243
 244                 printk(KERN_NOTICE "Updating U-boot image:\n");
 245                 printk(KERN_NOTICE "  old: [size: %8d crc32: 0x%08x]\n",
 246                         be32_to_cpu(uhdr.ih_size), be32_to_cpu(uhdr.ih_dcrc));
 247
 248                 /* Update the data length & crc32 */
 249                 uhdr.ih_size = cpu_to_be32(linux_len - sizeof(uhdr));
 250                 uhdr.ih_dcrc = crc32_le(~0, data, linux_len - sizeof(uhdr)) ^ (~0);
 251                 uhdr.ih_dcrc = cpu_to_be32(uhdr.ih_dcrc);
 252
 253                 printk(KERN_NOTICE "  new: [size: %8d crc32: 0x%08x]\n",
 254                         be32_to_cpu(uhdr.ih_size), be32_to_cpu(uhdr.ih_dcrc));
 255
 256                 /* update header's crc... */
 257                 uhdr.ih_hcrc = 0;
 258                 uhdr.ih_hcrc = crc32_le(~0, (unsigned char *)&uhdr,
 259                                 sizeof(uhdr)) ^ (~0);
 260                 uhdr.ih_hcrc = cpu_to_be32(uhdr.ih_hcrc);
 261
 262                 /* read first eraseblock from the image */
 263                 block = kmalloc(mtd->erasesize, GFP_KERNEL);
 264                 if (mtd->read(mtd, adm8668_parts[PART_LINUX].offset, mtd->erasesize, &len, block) || len != mtd->erasesize) {
 265                         printk("Error copying first eraseblock\n");
 266                         return 0;
 267                 }
 268
 269                 /* Write updated header to the flash */
 270                 memcpy(block, &uhdr, sizeof(uhdr));
 271                 if (mtd->unlock)
 272                         mtd->unlock(mtd, off, mtd->erasesize);
 273                 erase_write(mtd, adm8668_parts[PART_LINUX].offset, mtd->erasesize, block);
 274                 if (mtd->sync)
 275                         mtd->sync(mtd);
 276                 kfree(block);
 277                 printk(KERN_NOTICE "Done\n");
 278         }
 279
 280         return NR_PARTS;
 281 }
 282
 283 int __init init_adm8668_map(void)
 284 {
 285         int nr_parts, ret;
 286
 287         adm8668_map.virt = ioremap(WINDOW_ADDR, WINDOW_SIZE);
 288
 289         if (!adm8668_map.virt) {
 290                 printk(KERN_ERR "Failed to ioremap\n");
 291                 return -EIO;
 292         }
 293
 294         simple_map_init(&adm8668_map);
 295         if (!(adm8668_mtd = do_map_probe("cfi_probe", &adm8668_map))) {
 296                 printk(KERN_ERR "cfi_probe failed\n");
 297                 iounmap((void *)adm8668_map.virt);
 298                 return -ENXIO;
 299         }
 300
 301         adm8668_mtd->owner = THIS_MODULE;
 302
 303         nr_parts = init_mtd_partitions(adm8668_mtd, adm8668_mtd->size);
 304         ret = mtd_device_register(adm8668_mtd, adm8668_parts, nr_parts);
 305         if (ret) {
 306                 printk(KERN_ERR "Flash: mtd_device_register failed\n");
 307                 goto fail;
 308         }
 309
 310         return 0;
 311
 312  fail:
 313         if (adm8668_mtd)
 314                 map_destroy(adm8668_mtd);
 315         if (adm8668_map.virt)
 316                 iounmap((void *) adm8668_map.virt);
 317         adm8668_map.virt = 0;
 318         return ret;
 319 }
 320
 321 void __exit cleanup_adm8668_map(void)
 322 {
 323         mtd_device_unregister(adm8668_mtd);
 324         map_destroy(adm8668_mtd);
 325         iounmap((void *) adm8668_map.virt);
 326         adm8668_map.virt = 0;
 327 }
 328
 329 module_init(init_adm8668_map);
 330 module_exit(cleanup_adm8668_map);
 331
 332 MODULE_LICENSE("GPL");
 333 MODULE_AUTHOR("Scott Nicholas <neutronscott@scottn.us>");
 334 MODULE_DESCRIPTION("MTD map driver for ADM8668 NOR Flash");