From ea116654aaef4b3a7aaa3c2736f7ec5cf438a8a9 Mon Sep 17 00:00:00 2001
From: Jared Baur <jaredbaur@fastmail.com>
Date: Thu, 2 Jan 2025 11:30:45 -0800
Subject: [PATCH] nixos/initrd: add extraFirmwarePaths option

(cherry picked from commit 488d4316b9e1510c9b4a2eeb8d7e2cc66839a1fc)
---
 nixos/modules/system/boot/stage-1.nix         | 9 +++++++++
 nixos/modules/system/boot/systemd/initrd.nix  | 1 +
 pkgs/build-support/kernel/modules-closure.nix | 2 ++
 pkgs/build-support/kernel/modules-closure.sh  | 9 +++++++++
 pkgs/top-level/all-packages.nix               | 4 ++--
 5 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/nixos/modules/system/boot/stage-1.nix b/nixos/modules/system/boot/stage-1.nix
index ff7cf4777ddf..1aab9548a595 100644
--- a/nixos/modules/system/boot/stage-1.nix
+++ b/nixos/modules/system/boot/stage-1.nix
@@ -19,6 +19,7 @@ let
     kernel = config.system.modulesTree;
     firmware = config.hardware.firmware;
     allowMissing = false;
+    inherit (config.boot.initrd) extraFirmwarePaths;
   };
 
 
@@ -484,6 +485,14 @@ in
       '';
     };
 
+    boot.initrd.extraFirmwarePaths = mkOption {
+      default = [ ];
+      type = types.listOf types.str;
+      description = ''
+        Other firmware files (relative to `"''${config.hardware.firmware}/lib/firmware"`) to include in the final initrd we are building.
+      '';
+    };
+
     boot.initrd.checkJournalingFS = mkOption {
       default = true;
       type = types.bool;
diff --git a/nixos/modules/system/boot/systemd/initrd.nix b/nixos/modules/system/boot/systemd/initrd.nix
index 472c72fb3889..e56fb3702911 100644
--- a/nixos/modules/system/boot/systemd/initrd.nix
+++ b/nixos/modules/system/boot/systemd/initrd.nix
@@ -105,6 +105,7 @@ let
     kernel = config.system.modulesTree;
     firmware = config.hardware.firmware;
     allowMissing = false;
+    inherit (config.boot.initrd) extraFirmwarePaths;
   };
 
   initrdBinEnv = pkgs.buildEnv {
diff --git a/pkgs/build-support/kernel/modules-closure.nix b/pkgs/build-support/kernel/modules-closure.nix
index a830c97eea9a..611c01abe018 100644
--- a/pkgs/build-support/kernel/modules-closure.nix
+++ b/pkgs/build-support/kernel/modules-closure.nix
@@ -11,6 +11,7 @@
   rootModules,
   kmod,
   allowMissing ? false,
+  extraFirmwarePaths ? [ ],
 }:
 
 stdenvNoCC.mkDerivation {
@@ -25,6 +26,7 @@ stdenvNoCC.mkDerivation {
     firmware
     rootModules
     allowMissing
+    extraFirmwarePaths
     ;
   allowedReferences = [ "out" ];
 }
diff --git a/pkgs/build-support/kernel/modules-closure.sh b/pkgs/build-support/kernel/modules-closure.sh
index b53c64e30525..45423d21a570 100644
--- a/pkgs/build-support/kernel/modules-closure.sh
+++ b/pkgs/build-support/kernel/modules-closure.sh
@@ -87,6 +87,15 @@ for module in $(< ~-/closure); do
     done || :
 done
 
+for path in $extraFirmwarePaths; do
+    mkdir -p $(dirname $out/lib/firmware/$path)
+    for name in "$path" "$path.xz" "$path.zst" ""; do
+        if cp -v --parents --no-preserve=mode lib/firmware/$name "$out" 2>/dev/null; then
+            break
+        fi
+    done
+done
+
 if test -e lib/firmware/edid ; then
     echo "lib/firmware/edid found, copying."
     mkdir -p "$out/lib/firmware"
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index db392a2b84ea..569f3c2af566 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -709,9 +709,9 @@ with pkgs;
 
   compressFirmwareZstd = callPackage ../build-support/kernel/compress-firmware.nix { type = "zstd"; };
 
-  makeModulesClosure = { kernel, firmware, rootModules, allowMissing ? false }:
+  makeModulesClosure = { kernel, firmware, rootModules, allowMissing ? false, extraFirmwarePaths ? [ ] }:
     callPackage ../build-support/kernel/modules-closure.nix {
-      inherit kernel firmware rootModules allowMissing;
+      inherit kernel firmware rootModules allowMissing extraFirmwarePaths;
     };
 
   mkBinaryCache = callPackage ../build-support/binary-cache { };