29 lines
1.2 KiB
Plaintext
29 lines
1.2 KiB
Plaintext
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What: /sys/firmware/devicetree/*
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Date: November 2013
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Contact: Grant Likely <grant.likely@linaro.org>
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Description:
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When using OpenFirmware or a Flattened Device Tree to enumerate
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hardware, the device tree structure will be exposed in this
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directory.
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It is possible for multiple device-tree directories to exist.
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Some device drivers use a separate detached device tree which
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have no attachment to the system tree and will appear in a
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different subdirectory under /sys/firmware/devicetree.
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Userspace must not use the /sys/firmware/devicetree/base
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path directly, but instead should follow /proc/device-tree
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symlink. It is possible that the absolute path will change
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in the future, but the symlink is the stable ABI.
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The /proc/device-tree symlink replaces the devicetree /proc
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filesystem support, and has largely the same semantics and
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should be compatible with existing userspace.
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The contents of /sys/firmware/devicetree/ is a
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hierarchy of directories, one per device tree node. The
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directory name is the resolved path component name (node
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name plus address). Properties are represented as files
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in the directory. The contents of each file is the exact
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binary data from the device tree.
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