Redundancy - SOL-Space-Operating-Linux/meta-sol GitHub Wiki

Generalized boot concept for TX2/TX2i:

https://docs.nvidia.com/jetson/l4t/index.html#page/Tegra%2520Linux%2520Driver%2520Package%2520Development%2520Guide%2Fbootflow_tx2.html%23

This ends up being: SOCBootROM -> MB1 -> MB2 -> CBoot -> Uboot -> Kernel

With the NVIDIA built in redundancy, there is an _a and a _b side to mb1, mb2, cboot, uboot, kernel, dtb. Once past U-boot and DTB, however, there is generally no replication for rootfs. NVIDIA redundancy guide can be found here: https://docs.nvidia.com/jetson/l4t/index.html#page/Tegra%2520Linux%2520Driver%2520Package%2520Development%2520Guide%2Fbootloader_update_agx_tx2.html%23wwpID0E0AK0HA

meta-sol adds an additional rootfs partition and a capability to run completely out of a ram based file system. This ends up looking like:

Uboot -> /boot/initrd (initramfs)

  • create ramdisk
  • initramfs checks hash of roofts blob
  • if blob hash is correct, expand blob into ramdisk
  • if blob hash fails, check next partition and repeat
  • switch-root to ramdisk rootfs