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authorAnders Roxell <anders.roxell@linaro.org>2015-03-20 21:04:04 +0100
committerAnders Roxell <anders.roxell@linaro.org>2015-03-20 21:04:04 +0100
commit82fc0deb5fb5067c5207ace309b4e3af3eeec17b (patch)
treeb74cc762f65e4e8957098767b07e423f62cc38a4 /Documentation/ABI/testing/sysfs-firmware-ofw
parente20e8b472345ea5babd805db6726d1a7000f7673 (diff)
parent5210951a4876a42856434546d2789838d3e35f34 (diff)
Merge branch 'linux-linaro-lsk-v3.14' into linux-linaro-lsk-v3.14-rtlsk-v3.14-15.03-rt
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+What: /sys/firmware/devicetree/*
+Date: November 2013
+Contact: Grant Likely <grant.likely@linaro.org>
+Description:
+ When using OpenFirmware or a Flattened Device Tree to enumerate
+ hardware, the device tree structure will be exposed in this
+ directory.
+
+ It is possible for multiple device-tree directories to exist.
+ Some device drivers use a separate detached device tree which
+ have no attachment to the system tree and will appear in a
+ different subdirectory under /sys/firmware/devicetree.
+
+ Userspace must not use the /sys/firmware/devicetree/base
+ path directly, but instead should follow /proc/device-tree
+ symlink. It is possible that the absolute path will change
+ in the future, but the symlink is the stable ABI.
+
+ The /proc/device-tree symlink replaces the devicetree /proc
+ filesystem support, and has largely the same semantics and
+ should be compatible with existing userspace.
+
+ The contents of /sys/firmware/devicetree/ is a
+ hierarchy of directories, one per device tree node. The
+ directory name is the resolved path component name (node
+ name plus address). Properties are represented as files
+ in the directory. The contents of each file is the exact
+ binary data from the device tree.