====
Boot
====

The general boot chain and boot-time assets that don't belong to a single
loader stage: verified boot and image signing, the boot image (kernel/DTB/
ramdisk) and its recovery-image twin, the SoC register-level view of the
hand-off below UEFI, the base device tree, USB/QUP transport, and the
device-tree-overlay resources applied at boot. The two named loader
stages have their own sections: :doc:`/xbl/index` (PBL→XBL, XBL→ABL hand-off)
and :doc:`/abl/index` (the application bootloader itself, fastboot, AVB). The
boot splash shown during this whole sequence is documented next to the rest
of the display pipeline, in :doc:`/display/splash`.

.. toctree::
   :maxdepth: 1

   boot-chain
   secure-boot
   boot-image
   recovery
   keys
   below-uefi
   base-dtb
   usb-transport
   qup-buses
   dtbo