diff options
Diffstat (limited to 'kernel/Documentation/devicetree/dynamic-resolution-notes.txt')
| -rw-r--r-- | kernel/Documentation/devicetree/dynamic-resolution-notes.txt | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/kernel/Documentation/devicetree/dynamic-resolution-notes.txt b/kernel/Documentation/devicetree/dynamic-resolution-notes.txt new file mode 100644 index 000000000..083d23262 --- /dev/null +++ b/kernel/Documentation/devicetree/dynamic-resolution-notes.txt @@ -0,0 +1,25 @@ +Device Tree Dynamic Resolver Notes +---------------------------------- + +This document describes the implementation of the in-kernel +Device Tree resolver, residing in drivers/of/resolver.c and is a +companion document to Documentation/devicetree/dt-object-internal.txt[1] + +How the resolver works +---------------------- + +The resolver is given as an input an arbitrary tree compiled with the +proper dtc option and having a /plugin/ tag. This generates the +appropriate __fixups__ & __local_fixups__ nodes as described in [1]. + +In sequence the resolver works by the following steps: + +1. Get the maximum device tree phandle value from the live tree + 1. +2. Adjust all the local phandles of the tree to resolve by that amount. +3. Using the __local__fixups__ node information adjust all local references + by the same amount. +4. For each property in the __fixups__ node locate the node it references + in the live tree. This is the label used to tag the node. +5. Retrieve the phandle of the target of the fixup. +6. For each fixup in the property locate the node:property:offset location + and replace it with the phandle value. |