From: Ahmad Fatoum <[email protected]> global.of.overlay.path may point at a FIT image instead of a directory, but the documentation doesn't say which of its configurations are applied or how they are verified.
Let's add a short section on that. Unlike overlay files in a directory, the FIT is verified according to global.bootm.verify. Assisted-by: Claude:opus-5.5 Signed-off-by: Ahmad Fatoum <[email protected]> --- Documentation/user/devicetree.rst | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/Documentation/user/devicetree.rst b/Documentation/user/devicetree.rst index 5d26524809db..d8648d293e06 100644 --- a/Documentation/user/devicetree.rst +++ b/Documentation/user/devicetree.rst @@ -140,3 +140,18 @@ For upstream device trees, this is currently done on a case-by-case basis in the Makefiles:: DTC_FLAGS_bcm2711-rpi-4-b := -@ + +.. _of_overlay_fit: + +Overlays in a FIT image +^^^^^^^^^^^^^^^^^^^^^^^ + +If :ref:`global.of.overlay.path <magicvar_global_of_overlay_path>` points at a +file, barebox opens it as a FIT image and applies, in order, the first ``fdt`` +image of each configuration that has neither ``kernel`` nor ``firmware``. +:ref:`global.of.overlay.pattern <magicvar_global_of_overlay_pattern>` is +matched against the configuration name, not the image name. The FIT is +verified according to +:ref:`global.bootm.verify <magicvar_global_bootm_verify>`; overlays in a +directory are not verified at all. Processing stops at the first configuration +that fails to verify or apply, but the kernel is still booted. -- 2.47.3
