5. chumbyone Chumby Industrie’s Falconwing

This device is also known as “chumby one” (http://www.chumby.com/)

This CPU card is based on a Freescale i.MX23 CPU. The card is shipped with:

  • 64 MiB synchronous dynamic RAM (DDR type)

Memory layout when barebox is running:

  • 0x40000000 start of SDRAM
  • 0x40000100 start of kernel’s boot parameters
    • below malloc area: stack area
    • below barebox: malloc area
  • 0x42000000 start of barebox

5.1. How to get the bootloader binary image

Using the default configuration:

make ARCH=arm chumbyone_defconfig

Build the bootloader binary image:

make ARCH=arm CROSS_COMPILE=armv5compiler

NOTE: replace the armv5compiler with your ARM v5 cross compiler.

5.2. How to prepare an MCI card to boot the “chumby one” with barebox

  • Create four primary partitions on the MCI card
    • the first one for the bootlets (about 256 kiB)
    • the second one for the persistant environment (size is up to you, at least 256k)
    • the third one for the kernel (2 MiB ... 4 MiB in size)
    • the fourth one for the root filesystem which can fill the rest of the available space
  • Mark the first partition with the partition ID “53” and copy the bootlets into this partition (currently not part of barebox!).
  • Copy the default barebox environment into the second partition (no filesystem required).
  • Copy the kernel into the third partition (no filesystem required).
  • Create the root filesystem in the fourth partition. You may copy an image into this partition or you can do it in the classic way: mkfs on it, mount it and copy all required data and programs into it.