nixos/uvesafb: init

Signed-off-by: lucasew <[e-mail]>

nixos/modules/module-list.nix

···
   ./system/boot/systemd/user.nix
   ./system/boot/timesyncd.nix
   ./system/boot/tmp.nix
+  ./system/boot/uvesafb.nix
   ./system/etc/etc-activation.nix
   ./tasks/auto-upgrade.nix
   ./tasks/bcache.nix

nixos/modules/system/boot/uvesafb.nix

···
+{ config, lib, pkgs, ... }:
+let
+  cfg = config.boot.uvesafb;
+  inherit (lib) mkIf mkEnableOption mkOption mdDoc types;
+in {
+  options = {
+    boot.uvesafb = {
+      enable = mkEnableOption (mdDoc "uvesafb");
+
+      gfx-mode = mkOption {
+        type = types.str;
+        default = "1024x768-32";
+        description = mdDoc "Screen resolution in modedb format. See [uvesafb](https://docs.kernel.org/fb/uvesafb.html) and [modedb](https://docs.kernel.org/fb/modedb.html) documentation for more details. The default value is a sensible default but may be not ideal for all setups.";
+      };
+
+      v86d.package = mkOption {
+        type = types.package;
+        description = mdDoc "Which v86d package to use with uvesafb";
+        defaultText = ''config.boot.kernelPackages.v86d.overrideAttrs (old: {
+          hardeningDisable = [ "all" ];
+        })'';
+        default = config.boot.kernelPackages.v86d.overrideAttrs (old: {
+          hardeningDisable = [ "all" ];
+        });
+      };
+    };
+  };
+  config = mkIf cfg.enable {
+    boot.initrd = {
+      kernelModules = [ "uvesafb" ];
+      extraFiles."/usr/v86d".source = cfg.v86d.package;
+    };
+
+    boot.kernelParams = [
+      "video=uvesafb:mode:${cfg.gfx-mode},mtrr:3,ywrap"
+      ''uvesafb.v86d="${cfg.v86d.package}/bin/v86d"''
+    ];
+  };
+}