Add a git version check to the init scripts and make them work outside of the repo root. (#459)

* Fixes #453

- Update scripts/init-submodules-no-riscv-tools.sh to also work if you're in scripts/

- Provide a git version check to ensure the init scripts will work (>= 1.7.8)

- Update the documentation to be more explicit that the init script is also for updating.

* Update scripts/init-submodules-no-riscv-tools-nolog.sh

Co-Authored-By: Albert Ou <aou@eecs.berkeley.edu>

docs/Chipyard-Basics/Initial-Repo-Setup.rst

@@ -34,6 +34,9 @@ After cloning this repo, you will need to initialize all of the submodules.
     cd chipyard
     ./scripts/init-submodules-no-riscv-tools.sh
 
+When updating Chipyard to a new version, you will also want to rerun this script to update the submodules.
+Using git directly will try to initialize all submodules; this is not recommended unless you expressly desire this behavior.
+
 .. _build-toolchains:
 
 Building a Toolchain

scripts/init-submodules-no-riscv-tools-nolog.sh

@@ -4,6 +4,19 @@
 set -e
 set -o pipefail
 
+# Check that git version is at least 1.7.8
+MYGIT=$(git --version)
+MYGIT=${MYGIT#'git version '} # Strip prefix
+case ${MYGIT} in
+[1-9]*) ;;
+*) echo 'warning: unknown git version' ;;
+esac
+MINGIT="1.7.8"
+if [ "$MINGIT" != "$(echo -e "$MINGIT\n$MYGIT" | sort -V | head -n1)" ]; then
+  echo "This script requires git version $MINGIT or greater. Exiting."
+  false
+fi
+
 RDIR=$(git rev-parse --show-toplevel)
 
 # Ignore toolchain submodules
@@ -61,4 +74,3 @@ if [ ! -f $RDIR/software/firemarshal/marshal-config.yaml ]; then
   echo "firesim-dir: '../../sims/firesim/'" > $RDIR/software/firemarshal/marshal-config.yaml
 fi
 echo "PATH=\$( realpath \$(dirname "\${BASH_SOURCE[0]:-\${\(%\):-%x}}") )/software/firemarshal:\$PATH" >> $RDIR/env.sh
-

scripts/init-submodules-no-riscv-tools.sh

@@ -5,4 +5,7 @@
 set -e
 set -o pipefail
 
+RDIR=$(git rev-parse --show-toplevel)
+cd "$RDIR"
+
 ./scripts/init-submodules-no-riscv-tools-nolog.sh "$@" 2>&1 | tee init-submodules-no-riscv-tools.log