Revised the build system so that all packages that are to be automatically
downloaded and installed are done during "make" instead of during
"configure". This includes moving URLs into the Makefile, moving actions
like untarring into the download script, and replacing the "information"
file for the PDK with a custom download script.
diff --git a/sky130/custom/scripts/pdk_download.sh b/sky130/custom/scripts/pdk_download.sh
new file mode 100755
index 0000000..70f9ae0
--- /dev/null
+++ b/sky130/custom/scripts/pdk_download.sh
@@ -0,0 +1,32 @@
+#!/bin/sh
+#
+# pdk_download.sh --
+#
+# Download and install a PDK from git
+# (mainly for use with the Google/SkyWater SKY130 PDK)
+#
+# Usage: pdk_download.sh <url> <destination>
+#
+
+pdir=`dirname $2`
+mkdir -p $pdir
+cd $pdir
+
+# Clone repository
+
+echo "Cloning PDK repository"
+git clone $1 $2
+
+# Get submodules
+
+echo "Getting PDK library submodules"
+cd $2
+for i in $(git submodule | grep /latest | awk '{print $2}'); do
+ git submodule init $i
+done
+git submodule update
+
+# Generate liberty files
+
+echo "Building liberty timing files"
+make timing
