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27 lines
1.1 KiB
27 lines
1.1 KiB
.. SPDX-License-Identifier: GPL-2.0 |
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Devicetree Dynamic Resolver Notes |
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This document describes the implementation of the in-kernel |
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DeviceTree resolver, residing in drivers/of/resolver.c |
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How the resolver works |
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---------------------- |
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The resolver is given as an input an arbitrary tree compiled with the |
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proper dtc option and having a /plugin/ tag. This generates the |
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appropriate __fixups__ & __local_fixups__ nodes. |
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In sequence the resolver works by the following steps: |
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1. Get the maximum device tree phandle value from the live tree + 1. |
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2. Adjust all the local phandles of the tree to resolve by that amount. |
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3. Using the __local__fixups__ node information adjust all local references |
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by the same amount. |
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4. For each property in the __fixups__ node locate the node it references |
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in the live tree. This is the label used to tag the node. |
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5. Retrieve the phandle of the target of the fixup. |
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6. For each fixup in the property locate the node:property:offset location |
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and replace it with the phandle value.
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