Basic alpine chroot

makefile

@@ -39,3 +39,21 @@ itb: fit-build
 		--build-arg DEVICE_TREE_TARGET=$(DEVICE_TREE_TARGET) \
 		--output type=local,dest=./out \
 	-t $(DOCKER_IMAGE_ROOT)/itb:$(TAG) .
+
+buildenv-alpine: build-base
+	docker build \
+	-f docker/alpine.Dockerfile \
+		--build-arg DOCKER_IMAGE_ROOT=$(DOCKER_IMAGE_ROOT) \
+		--build-arg TAG=$(TAG) \
+		--build-arg ALPINE_ARCH=$(ALPINE_ARCH) \
+		--build-arg ALPINE_VER=$(ALPINE_VER) \
+	-t $(DOCKER_IMAGE_ROOT)/buildenv-alpine:$(TAG) .
+
+alpine-rootfs: buildenv-alpine
+	docker run --rm -it \
+		--privileged \
+		-v /cache/apk:/var/cache/apk \
+		-v /cache/artifacts:/artifacts \
+		-e ROOTFS=/out/rootfs \
+		$(DOCKER_IMAGE_ROOT)/buildenv-alpine:$(TAG) \
+		bash -lc '/prepare-chroot.sh && /build-rootfs.sh'