build: Updated development utilities for AArch64

Updated Dockerfile to work with multiple architectures.
Updated dev_cli.sh to:
1. Build container image before AArch64 image is ready in public.
2. Adjust default feature collection on AArch64.
3. Workaround a build problem with musl on AArch64.

Signed-off-by: Michael Zhao <michael.zhao@arm.com>

resources/Dockerfile

@@ -1,5 +1,6 @@
 FROM ubuntu:18.04 as dev
 
+ARG TARGETARCH="x86_64"
 ARG RUST_TOOLCHAIN="1.42.0"
 ARG CLH_SRC_DIR="/cloud-hypervisor"
 ARG CLH_BUILD_DIR="$CLH_SRC_DIR/build"
@@ -11,9 +12,9 @@ ENV RUSTUP_HOME=$CARGO_HOME
 ENV PATH="$PATH:$CARGO_HOME/bin"
 
 # Install all CI dependencies
-RUN apt-get update
-RUN apt-get -yq upgrade
-RUN DEBIAN_FRONTEND=noninteractive apt-get install -yq \
+RUN apt-get update \
+	&& apt-get -yq upgrade \
+	&& DEBIAN_FRONTEND=noninteractive apt-get install -yq \
 	build-essential \
 	bc \
 	docker.io \
@@ -37,22 +38,29 @@ RUN DEBIAN_FRONTEND=noninteractive apt-get install -yq \
 	dosfstools \
 	cpio \
 	bsdtar \
-	gcc-multilib \
+	libfdt-dev \
     && apt-get clean \
     && rm -rf /var/lib/apt/lists/*
 
+RUN if [ "$TARGETARCH" = "x86_64" ]; then \
+	apt-get update \
+	&& apt-get -yq upgrade \
+	&& DEBIAN_FRONTEND=noninteractive apt-get install -yq gcc-multilib \
+	&& apt-get clean \
+    && rm -rf /var/lib/apt/lists/*;	fi
+
 # Fix the libssl-dev install
-RUN cp /usr/include/x86_64-linux-gnu/openssl/opensslconf.h /usr/include/openssl/
-ENV OPENSSL_DIR=/usr/lib/x86_64-linux-gnu/
-ENV OPENSSL_LIB_DIR=/usr/lib/x86_64-linux-gnu/
+RUN cp /usr/include/"$TARGETARCH"-linux-gnu/openssl/opensslconf.h /usr/include/openssl/
+ENV OPENSSL_DIR=/usr/lib/"$TARGETARCH"-linux-gnu/
+ENV OPENSSL_LIB_DIR=/usr/lib/"$TARGETARCH"-linux-gnu/
 ENV OPENSSL_INCLUDE_DIR=/usr/include/
 
 # Install the rust toolchain
 RUN nohup curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --default-toolchain "$RUST_TOOLCHAIN" \
-    && rustup target add x86_64-unknown-linux-musl --toolchain "$RUST_TOOLCHAIN" \
-    && rustup toolchain add $RUST_TOOLCHAIN-x86_64-unknown-linux-musl \
-    && rustup component add rustfmt \
-    && rustup component add clippy \
+    && rustup target add $TARGETARCH-unknown-linux-musl --toolchain "$RUST_TOOLCHAIN" \
+    && if [ "$TARGETARCH" = "x86_64" ]; then rustup toolchain add $RUST_TOOLCHAIN-x86_64-unknown-linux-musl; fi \
+    && if [ "$TARGETARCH" = "x86_64" ]; then rustup component add rustfmt; fi \
+    && if [ "$TARGETARCH" = "x86_64" ]; then rustup component add clippy; fi \
     && cargo install cargo-audit \
     && rm -rf "$CARGO_HOME/registry" \
     && ln -s "$CARGO_REGISTRY_DIR" "$CARGO_HOME/registry" \

scripts/dev_cli.sh

@@ -200,6 +200,13 @@ cmd_build() {
     cargo_args=("$@")
     [ $build = "release" ] && cargo_args+=("--release")
     cargo_args+=(--target "$target")
+    [ $(uname -m) = "aarch64" ] && cargo_args+=("--no-default-features")
+    [ $(uname -m) = "aarch64" ] && cargo_args+=(--features "mmio")
+
+    rustflags=""
+    if [ $(uname -m) = "aarch64" ] && [ $libc = "musl" ] ; then
+        rustflags="-C link-arg=-lgcc"
+    fi
 
     $DOCKER_RUNTIME run \
 	   --user "$(id -u):$(id -g)" \
@@ -207,6 +214,7 @@ cmd_build() {
 	   --rm \
 	   --volume /dev:/dev \
 	   --volume "$CLH_ROOT_DIR:$CTR_CLH_ROOT_DIR" \
+	   --env RUSTFLAGS="$rustflags" \
 	   "$CTR_IMAGE" \
 	   cargo build \
 	         --target-dir "$CTR_CLH_CARGO_TARGET" \
@@ -336,6 +344,7 @@ cmd_build-container() {
 	   --target $container_type \
 	   -t $CTR_IMAGE \
 	   -f $BUILD_DIR/Dockerfile \
+	   --build-arg TARGETARCH="$(uname -m)" \
 	   $BUILD_DIR
 }
 
@@ -365,6 +374,13 @@ cmd=cmd_$1
 shift
 
 ensure_build_dir
-ensure_latest_ctr
+if [ $(uname -m) = "x86_64" ]; then
+    ensure_latest_ctr
+fi
+
+# Before a public image for AArch64 ready, we build the container if needed.
+if [ $(uname -m) = "aarch64" ]; then
+    cmd_build-container
+fi
 
 $cmd "$@"