1.. SPDX-License-Identifier: GPL-2.0 2 3================================= 4Devicetree Dynamic Resolver Notes 5================================= 6 7This document describes the implementation of the in-kernel 8DeviceTree resolver, residing in drivers/of/resolver.c 9 10How the resolver works 11---------------------- 12 13The resolver is given as an input an arbitrary tree compiled with the 14proper dtc option and having a /plugin/ tag. This generates the 15appropriate __fixups__ & __local_fixups__ nodes. 16 17In sequence the resolver works by the following steps: 18 191. Get the maximum device tree phandle value from the live tree + 1. 202. Adjust all the local phandles of the tree to resolve by that amount. 213. Using the __local__fixups__ node information adjust all local references 22 by the same amount. 234. For each property in the __fixups__ node locate the node it references 24 in the live tree. This is the label used to tag the node. 255. Retrieve the phandle of the target of the fixup. 266. For each fixup in the property locate the node:property:offset location 27 and replace it with the phandle value. 28