target/linux/ramips/patches-3.8/0208-owrt-mtd-split.patch

   1 From 2a295753a10823a47542c779a25bbb1f52c71281 Mon Sep 17 00:00:00 2001
   2 From: John Crispin <blogic@openwrt.org>
   3 Date: Fri, 3 Aug 2012 10:27:13 +0200
   4 Subject: [PATCH 19/25] owrt mtd split
   5
   6 ---
   7  .../mips/include/asm/mach-lantiq/xway/lantiq_soc.h |    1 +
   8  arch/mips/lantiq/setup.c                           |    7 +
   9  drivers/mtd/Kconfig                                |    4 +
  10  drivers/mtd/mtdpart.c                              |  173 +++++++++++++++++++-
  11  4 files changed, 184 insertions(+), 1 deletions(-)
  12
  13 --- a/drivers/mtd/Kconfig
  14 +++ b/drivers/mtd/Kconfig
  15 @@ -31,6 +31,10 @@ config MTD_ROOTFS_SPLIT
  16         bool "Automatically split 'rootfs' partition for squashfs"
  17         default y
  18
  19 +config MTD_UIMAGE_SPLIT
  20 +       bool "Automatically split 'linux' partition into 'kernel' and 'rootfs'"
  21 +       default y
  22 +
  23  config MTD_REDBOOT_PARTS
  24         tristate "RedBoot partition table parsing"
  25         ---help---
  26 --- a/drivers/mtd/mtdpart.c
  27 +++ b/drivers/mtd/mtdpart.c
  28 @@ -833,6 +833,99 @@ static int refresh_rootfs_split(struct m
  29  }
  30  #endif /* CONFIG_MTD_ROOTFS_SPLIT */
  31
  32 +#ifdef CONFIG_MTD_UIMAGE_SPLIT
  33 +static unsigned long find_uimage_size(struct mtd_info *mtd,
  34 +                                     unsigned long offset)
  35 +{
  36 +#define UBOOT_MAGIC    0x56190527
  37 +       unsigned long magic = 0;
  38 +       unsigned long temp;
  39 +       size_t len;
  40 +       int ret;
  41 +
  42 +       ret = mtd_read(mtd, offset, 4, &len, (void *)&magic);
  43 +       if (ret || len != sizeof(magic))
  44 +               return 0;
  45 +
  46 +       if (le32_to_cpu(magic) != UBOOT_MAGIC)
  47 +               return 0;
  48 +
  49 +       ret = mtd_read(mtd, offset + 12, 4, &len, (void *)&temp);
  50 +       if (ret || len != sizeof(temp))
  51 +               return 0;
  52 +
  53 +       return be32_to_cpu(temp) + 0x40;
  54 +}
  55 +
  56 +static int detect_squashfs_partition(struct mtd_info *mtd, unsigned long offset)
  57 +{
  58 +       unsigned long temp;
  59 +       size_t len;
  60 +       int ret;
  61 +
  62 +       ret = mtd_read(mtd, offset, 4, &len, (void *)&temp);
  63 +       if (ret || len != sizeof(temp))
  64 +               return 0;
  65 +
  66 +       return le32_to_cpu(temp) == SQUASHFS_MAGIC;
  67 +}
  68 +
  69 +static unsigned long find_squashfs_offset(struct mtd_info *mtd, unsigned long _offset)
  70 +{
  71 +       /* scan the first 2MB at 64K offsets */
  72 +       int i;
  73 +
  74 +       for (i = 0; i < 32; i++) {
  75 +               unsigned long offset = i * 64 * 1024;
  76 +               if (detect_squashfs_partition(mtd, _offset + offset))
  77 +                       return offset;
  78 +       }
  79 +       return 0;
  80 +}
  81 +
  82 +static int split_uimage(struct mtd_info *mtd,
  83 +                       const struct mtd_partition *part)
  84 +{
  85 +       static struct mtd_partition split_partitions[] = {
  86 +               {
  87 +                       .name = "kernel",
  88 +                       .offset = 0x0,
  89 +                       .size = 0x0,
  90 +               }, {
  91 +                       .name = "rootfs",
  92 +                       .offset = 0x0,
  93 +                       .size = 0x0,
  94 +               },
  95 +       };
  96 +
  97 +       split_partitions[0].size = find_uimage_size(mtd, part->offset);
  98 +       if (!split_partitions[0].size) {
  99 +               split_partitions[0].size = find_squashfs_offset(mtd, part->offset);
 100 +               if (!split_partitions[0].size) {
 101 +                       pr_err("failed to split firmware partition\n");
 102 +                       return -1;
 103 +               }
 104 +       }
 105 +
 106 +       if (!detect_squashfs_partition(mtd,
 107 +                                      part->offset
 108 +                                      + split_partitions[0].size)) {
 109 +               split_partitions[0].size &= ~(mtd->erasesize - 1);
 110 +               split_partitions[0].size += mtd->erasesize;
 111 +       } else {
 112 +               pr_info("found squashfs behind kernel\n");
 113 +       }
 114 +
 115 +       split_partitions[0].offset = part->offset;
 116 +       split_partitions[1].offset = part->offset + split_partitions[0].size;
 117 +       split_partitions[1].size = part->size - split_partitions[0].size;
 118 +
 119 +       add_mtd_partitions(mtd, split_partitions, 2);
 120 +
 121 +       return 0;
 122 +}
 123 +#endif
 124 +
 125  /*
 126   * This function, given a master MTD object and a partition table, creates
 127   * and registers slave MTD objects which are bound to the master according to
 128 @@ -849,7 +942,7 @@ int add_mtd_partitions(struct mtd_info *
 129         struct mtd_part *slave;
 130         uint64_t cur_offset = 0;
 131         int i;
 132 -#ifdef CONFIG_MTD_ROOTFS_SPLIT
 133 +#if defined(CONFIG_MTD_ROOTFS_SPLIT) || defined(CONFIG_MTD_UIMAGE_SPLIT)
 134         int ret;
 135  #endif
 136
 137 @@ -866,6 +959,14 @@ int add_mtd_partitions(struct mtd_info *
 138
 139                 add_mtd_device(&slave->mtd);
 140
 141 +#ifdef CONFIG_MTD_UIMAGE_SPLIT
 142 +               if (!strcmp(parts[i].name, "firmware")) {
 143 +                       ret = split_uimage(master, &parts[i]);
 144 +                       if (ret)
 145 +                               printk(KERN_WARNING "Can't split firmware partition\n");
 146 +               }
 147 +#endif
 148 +
 149                 if (!strcmp(parts[i].name, "rootfs")) {
 150  #ifdef CONFIG_MTD_ROOTFS_ROOT_DEV
 151                         if (ROOT_DEV == 0) {