From 7c6320f66dce97927d6959aba19dc3f762eda6a5 Mon Sep 17 00:00:00 2001
From: Florian Agbuya <fa@m-labs.ph>
Date: Fri, 5 Apr 2024 15:22:13 +0800
Subject: [PATCH] configure loading of bitstream at boot time

---
 flake.nix | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/flake.nix b/flake.nix
index 3330a6b..bda13f9 100644
--- a/flake.nix
+++ b/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;