{ lib, stdenvNoCC, dtc }: with lib; { applyOverlays = (base: overlays': stdenvNoCC.mkDerivation { name = "device-tree-overlays"; nativeBuildInputs = [ dtc ]; buildCommand = let overlays = toList overlays'; in '' mkdir -p $out cd "${base}" find . -type f -name '*.dtb' -print0 \ | xargs -0 cp -v --no-preserve=mode --target-directory "$out" --parents for dtb in $(find "$out" -type f -name '*.dtb'); do dtbCompat=$(fdtget -t s "$dtb" / compatible 2>/dev/null || true) # skip files without `compatible` string test -z "$dtbCompat" && continue ${flip (concatMapStringsSep "\n") overlays (o: '' overlayCompat="$(fdtget -t s "${o.dtboFile}" / compatible)" # skip incompatible and non-matching overlays if [[ ! "$dtbCompat" =~ "$overlayCompat" ]]; then echo -n "Skipping overlay ${o.name}: incompatible with $(basename "$dtb")" continue fi ${optionalString (o.filter != null) '' if [[ "''${dtb//${o.filter}/}" == "$dtb" ]]; then echo -n "Skipping overlay ${o.name}: filter does not match $(basename "$dtb")" continue fi ''} echo -n "Applying overlay ${o.name} to $(basename "$dtb")... " mv "$dtb"{,.in} fdtoverlay -o "$dtb" -i "$dtb.in" "${o.dtboFile}" echo "ok" rm "$dtb.in" '')} done ''; }); }