| 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. |
