nerves_system_rpi

#
# Firmware metadata
#

# All of these can be overriden using environment variables of the same name.
#
#  Run 'fwup -m' to query values in a .fw file.
#  Use 'fw_printenv' to query values on the target.
#
# These are used by Nerves libraries to introspect.
define(NERVES_FW_PRODUCT, "Nerves Firmware")
define(NERVES_FW_DESCRIPTION, "")
define(NERVES_FW_VERSION, "${NERVES_SDK_VERSION}")
define(NERVES_FW_PLATFORM, "rpi")
define(NERVES_FW_ARCHITECTURE, "arm")
define(NERVES_FW_AUTHOR, "The Nerves Team")

define(NERVES_FW_DEVPATH, "/dev/mmcblk0")
define(NERVES_FW_APPLICATION_PART0_DEVPATH, "/dev/mmcblk0p3") # Linux part number is 1-based
define(NERVES_FW_APPLICATION_PART0_FSTYPE, "ext4")
define(NERVES_FW_APPLICATION_PART0_TARGET, "/root")
define(NERVES_PROVISIONING, "${NERVES_SYSTEM}/images/fwup_include/provisioning.conf")

# Default paths if not specified via the commandline
define(ROOTFS, "${NERVES_SYSTEM}/images/rootfs.squashfs")

# This configuration file will create an image that has an MBR and the
# following 3 partitions:
#
# +----------------------------+
# | MBR                        |
# +----------------------------+
# | Firmware configuration data|
# | (formatted as uboot env)   |
# +----------------------------+
# | p0*: Boot A (FAT32)        |
# | zImage, bootcode.bin,      |
# | config.txt, etc.           |
# +----------------------------+
# | p0*: Boot B (FAT32)        |
# +----------------------------+
# | p1*: Rootfs A (squashfs)   |
# +----------------------------+
# | p1*: Rootfs B (squashfs)   |
# +----------------------------+
# | p2: Application (ext4)     |
# +----------------------------+
#
# The p0/p1 partition points to whichever of configurations A or B that is
# active.
#
# The image is sized to be less than 1 GB so that it fits on nearly any SDCard
# around. If you have a larger SDCard and need more space, feel free to bump
# the partition sizes below.

# The Raspberry Pi is incredibly picky on the partition sizes and in ways that
# I don't understand. Test changes one at a time to make sure that they boot.
# (Sizes are in 512 byte blocks)
define(UBOOT_ENV_OFFSET, 16)
define(UBOOT_ENV_COUNT, 16)  # 8 KB

define(BOOT_A_PART_OFFSET, 63)
define(BOOT_A_PART_COUNT, 38630)
define-eval(BOOT_B_PART_OFFSET, "${BOOT_A_PART_OFFSET} + ${BOOT_A_PART_COUNT}")
define(BOOT_B_PART_COUNT, ${BOOT_A_PART_COUNT})

# Let the rootfs have room to grow up to 128 MiB and align it to the nearest 1
# MB boundary
define(ROOTFS_A_PART_OFFSET, 77324)
define(ROOTFS_A_PART_COUNT, 289044)
define-eval(ROOTFS_B_PART_OFFSET, "${ROOTFS_A_PART_OFFSET} + ${ROOTFS_A_PART_COUNT}")
define(ROOTFS_B_PART_COUNT, ${ROOTFS_A_PART_COUNT})

# Application partition. This partition can occupy all of the remaining space.
# Size it to fit the destination.
define-eval(APP_PART_OFFSET, "${ROOTFS_B_PART_OFFSET} + ${ROOTFS_B_PART_COUNT}")
define(APP_PART_COUNT, 1048576)

# Firmware archive metadata
meta-product = ${NERVES_FW_PRODUCT}
meta-description = ${NERVES_FW_DESCRIPTION}
meta-version = ${NERVES_FW_VERSION}
meta-platform = ${NERVES_FW_PLATFORM}
meta-architecture = ${NERVES_FW_ARCHITECTURE}
meta-author = ${NERVES_FW_AUTHOR}
meta-vcs-identifier = ${NERVES_FW_VCS_IDENTIFIER}
meta-misc = ${NERVES_FW_MISC}

mbr mbr-a {
    partition 0 {
        block-offset = ${BOOT_A_PART_OFFSET}
        block-count = ${BOOT_A_PART_COUNT}
        type = 0xc # FAT32
        boot = true
    }
    partition 1 {
        block-offset = ${ROOTFS_A_PART_OFFSET}
        block-count = ${ROOTFS_A_PART_COUNT}
        type = 0x83 # Linux
    }
    partition 2 {
        block-offset = ${APP_PART_OFFSET}
        block-count = ${APP_PART_COUNT}
        type = 0x83 # Linux
        expand = true
    }
    # partition 3 is unused
}

mbr mbr-b {
    partition 0 {
        block-offset = ${BOOT_B_PART_OFFSET}
        block-count = ${BOOT_B_PART_COUNT}
        type = 0xc # FAT32
        boot = true
    }
    partition 1 {
        block-offset = ${ROOTFS_B_PART_OFFSET}
        block-count = ${ROOTFS_B_PART_COUNT}
        type = 0x83 # Linux
    }
    partition 2 {
        block-offset = ${APP_PART_OFFSET}
        block-count = ${APP_PART_COUNT}
        type = 0x83 # Linux
        expand = true
    }
    # partition 3 is unused
}

# Location where installed firmware information is stored.
# While this is called "u-boot", u-boot isn't involved in this
# setup. It just provides a convenient key/value store format.
uboot-environment uboot-env {
    block-offset = ${UBOOT_ENV_OFFSET}
    block-count = ${UBOOT_ENV_COUNT}
}