dtmerge is a tool for applying pre-compiled overlays (*.dtbo files) to a
base Device Tree file (*.dtb).
dtoverlay is a tool for applying pre-compiled overlays to a live system. dtparam is a tool for applying paramaters of the base Device Tree of a live system.
Build Instructions
Install the prerequisites with "sudo apt install cmake libfdt-dev" - you need at least version 3.10 of cmake. Run the following commands here, or in the top-level directory to build and install all the utilities:
- cmake .
- make
- sudo make install
Usage
Usage:
dtmerge [<options] <base dtb> <merged dtb> - [param=value] ...
to apply a parameter to the base dtb (like dtparam)
dtmerge [<options] <base dtb> <merged dtb> <overlay dtb> [param=value] ...
to apply an overlay with parameters (like dtoverlay)
where <options> is any of:
-d Enable debug output
-h Show this help message
Usage:
dtoverlay <overlay> [<param>=<val>...]
Add an overlay (with parameters)
dtoverlay -D Dry-run (prepare overlay, but don't apply -
save it as dry-run.dtbo)
dtoverlay -r [<overlay>] Remove an overlay (by name, index or the last)
dtoverlay -R [<overlay>] Remove from an overlay (by name, index or all)
dtoverlay -l List active overlays/params
dtoverlay -a List all overlays (marking the active)
dtoverlay -h Show this usage message
dtoverlay -h <overlay> Display help on an overlay
dtoverlay -h <overlay> <param>.. Or its parameters
where <overlay> is the name of an overlay or 'dtparam' for dtparams
Options applicable to most variants:
-d <dir> Specify an alternate location for the overlays
(defaults to /boot/overlays or /flash/overlays)
-p <string> Force a compatible string for the platform
-v Verbose operation
Adding or removing overlays and parameters requires root privileges.
Usage:
dtparam Display help on all parameters
dtparam <param>=<val>...
Add an overlay (with parameters)
dtparam -D Dry-run (prepare overlay, but don't apply -
save it as dry-run.dtbo)
dtparam -r [<idx>] Remove an overlay (by index, or the last)
dtparam -R [<idx>] Remove from an overlay (by index, or all)
dtparam -l List active overlays/dtparams
dtparam -a List all overlays/dtparams (marking the active)
dtparam -h Show this usage message
dtparam -h <param>... Display help on the listed parameters
Options applicable to most variants:
-d <dir> Specify an alternate location for the overlays
(defaults to /boot/overlays or /flash/overlays)
-p <string> Force a compatible string for the platform
-v Verbose operation
Adding or removing overlays and parameters requires root privileges.