initrd-kernel: Allows embedding modules.

modules/initrd-kernel.nix

@@ -0,0 +1,82 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+with import ./initrd-order.nix;
+
+let
+  cfg = config.mobile.boot.stage-1.kernel;
+  device_config = config.mobile.device;
+
+  inherit (device_config.info) kernel;
+  modulesClosure = pkgs.makeModulesClosure {
+    inherit kernel;
+    allowMissing = true;
+    rootModules = cfg.modules ++ cfg.additional_modules;
+    firmware = cfg.firmwares;
+  };
+in
+{
+  options.mobile.boot.stage-1.kernel = {
+    modular = mkOption {
+      type = types.bool;
+      default = false;
+      description = ''
+        Whether the kernel is built with modules or not.
+        This will enable modules closure generation and listing modules
+        to bundle and load.
+      '';
+    };
+    modules = mkOption {
+      type = types.listOf types.string;
+      default = [
+      ];
+      description = ''
+        Module names to add to the closure.
+        They will be modprobed.
+      '';
+    };
+    additional_modules = mkOption {
+      type = types.listOf types.string;
+      default = [
+      ];
+      description = ''
+        Module names to add to the closure.
+        They will not be modprobed.
+      '';
+    };
+    firmwares = mkOption {
+      type = types.listOf types.string;
+      default = [];
+      description = ''
+        Firmwares to add to the cloure.
+      '';
+    };
+  };
+
+  config.mobile.boot.stage-1 = mkIf cfg.modular {
+    contents = [ { object = modulesClosure; symlink = "/.kernel-modules"; } ];
+    init = lib.mkOrder BEFORE_DEVICE_INIT ''
+      mkdir -p /lib
+      ln -s ${modulesClosure}/lib/modules/ lib/modules
+      ln -s ${modulesClosure}/lib/firmware/ lib/firmware
+
+      ${
+        lib.concatMapStringsSep "\n" (mod: ''modprobe ${mod}'') cfg.modules
+      }
+    '';
+    kernel.modules = [
+      # Basic always-needed kernel modules.
+      "loop"
+
+      # Filesystems
+      "nls_cp437"
+      "nls_iso8859-1"
+      "fat"
+      "vfat"
+
+      "ext4"
+      "crc32c"
+    ];
+  };
+}
+

modules/module-list.nix

@@ -11,6 +11,7 @@
   ./initrd-base.nix
   ./initrd-devices.nix
   ./initrd-framebuffer.nix
+  ./initrd-kernel.nix
   ./initrd-logger.nix
   ./initrd-loop.nix
   ./initrd-nc-shell.nix