diff --git a/build.sh b/build.sh
index 9f5b78a..1fde564 100755
--- a/build.sh
+++ b/build.sh
@@ -8,6 +8,7 @@ PACKAGE_FILE_NAME="sc64-extra"
 
 TOP_FILES=(
     "./fw/ftdi/ft232h_config.xml"
+    "./fw/project/lcmxo2/impl1/fpga_max_frequency.txt"
     "./sw/tools/primer.py"
     "./sw/tools/requirements.txt"
     "./sc64-firmware-${SC64_VERSION}.bin"
@@ -90,6 +91,7 @@ build_update () {
         rm -f ../../sc64-firmware-*.bin
     fi
     GIT_INFO=""
+    GIT_INFO+=$'\n'"freq: $(cat ../../fw/project/lcmxo2/impl1/fpga_max_frequency.txt)"
     if [ ! -z "${SC64_VERSION}" ]; then GIT_INFO+=$'\n'"ver: $SC64_VERSION"; fi
     if [ ! -z "${GIT_BRANCH}" ]; then GIT_INFO+=$'\n'"branch: $GIT_BRANCH"; fi
     if [ ! -z "${GIT_TAG}" ]; then GIT_INFO+=$'\n'"tag: $GIT_TAG"; fi
diff --git a/fw/project/lcmxo2/build.sh b/fw/project/lcmxo2/build.sh
index 35a8b44..ebe6849 100755
--- a/fw/project/lcmxo2/build.sh
+++ b/fw/project/lcmxo2/build.sh
@@ -1,5 +1,31 @@
 #!/bin/bash
 
+set -e
+
 source $bindir/diamond_env
 
 diamondc build.tcl
+
+MINIMUM_FREQ=$(cat impl1/sc64_impl1.twr \
+    | grep 'Preference: FREQUENCY NET "clk"' \
+    | head -1 \
+    | awk -F ' ' '{print $5}' \
+)
+
+DESIGN_FREQ=$(cat impl1/sc64_impl1.twr \
+    | sed -n '/Preference: FREQUENCY NET "clk"/,$p' \
+    | grep 'is the maximum frequency for this preference' \
+    | head -1 \
+    | awk -F ' ' '{print $2}' \
+    | sed 's/MHz//' \
+)
+
+echo "Minimum required frequency: $MINIMUM_FREQ MHz"
+echo "Maximum design frequency:   $DESIGN_FREQ MHz"
+
+if (( $(echo "$DESIGN_FREQ < $MINIMUM_FREQ" | bc -l) )); then
+    echo "Timing error detected, build failed"
+    exit 1
+fi
+
+echo -n "$DESIGN_FREQ MHz" > impl1/fpga_max_frequency.txt