Pre's flash disk

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The Pre's flash disk appears to the device as a MMC and uses the standard fdisk partition scheme, with a MBR-like structure in the first block. There are three partitions:

  1. type 0xf0 start 0x00000400 size 0x00002000 NVRAM and Tokens
  2. type 0x83 start 0x00002400 size 0x00010000 /boot (ext3)
  3. type 0x8e start 0x00012400 size 0x00f3dc00 Logical Volumes

The space between the MBR and the first partition are used to store the bootloader (Bootie). The /boot partition contains the linux kernel (in uImage format), a copy of the bootloader and the minimal userland required to start the LVM and to pivot the root to /dev/mapper/store-root and perform the "real" boot from there.

webos 1.4.5 Pre

The first 512K contains the MBR and Bootie.

The Flash is set up as follows:

  • MBR - 512 Bytes
  • Bootie Size - 4 Bytes
  • Load Address - 4 Bytes
  • Bootie - ~54K for Pre, ~105K for Pixi
  • ??? - Rest of 512K space before first partition
  • partition 1 (NVRM) - 4M
  • partition 2 (/boot) - 32M
  • partition 3 (LVM) - rest of Flash


  1. type 0xf0 start 0x00080000 size 0x00400000 NVRAM and Tokens
  2. type 0x83 start 0x00480000 size 0x02000000 /boot (ext3)
  3. type 0x8e start 0x02480000 size 0x1e7b8000 Logical Volumes