configure loading of bitstream at boot time

flake.nix

@@ -209,8 +209,18 @@
           extraModules = [
             "${patched-not-os}/zynq_image.nix"
           ] ++ pkgs.lib.optionals (board == "fast-servo") [
-            ({ config, pkgs, ... }: {
+            ({ config, pkgs, lib, ... }: {
               environment.systemPackages = [ linien-server ];
+              boot.postBootCommands = lib.mkAfter ''
+
+                # Program the FPGA
+                set +x
+                echo "Flashing bitstream..."
+                echo 0 > /sys/class/fpga_manager/fpga0/flags
+                mkdir -p /lib/firmware
+                cp ${fast-servo-gateware}/gateware.bin /lib/firmware/
+                echo gateware.bin > /sys/class/fpga_manager/fpga0/firmware
+              '';
             })];
           system = "x86_64-linux";
           inherit crossSystem;