NixOS on RISCV/VisionFive 2: Difference between revisions

@@ Line 86: / Line 86: @@
        });
 }
+</nowiki>}}
+If you want to use an alternative filesystem for system root, for example [[Btrfs]], you could change the <code>sdImage</code>-part to this. Currently [https://github.com/NixOS/nixpkgs/pull/434122 this patch] is required to produce a functioning btrfs image.
+{{file|flake.nix|nix|<nowiki>
+sdImage = {
+  compressImage = false;
+  rootFilesystemCreator = "${pkgs.path}/nixos/lib/make-btrfs-fs.nix";
+  # do this manually as replacing the resize2fs string in postBootCommands
+  # might be too complex. btrfs uses its own resize command.
+  expandOnBoot = false;
+};
+nixpkgs.overlays = [
+  (final: prev: {
+    ubootVisionFive2 = prev.ubootVisionFive2.overrideAttrs (oldAttrs: {
+      extraConfig = (oldAttrs.extraConfig or "") + ''
+        CONFIG_FS_BTRFS=y
+        CONFIG_CMD_BTRFS=y
+      '';
+    });
+  })
+];
+fileSystems."/" = {
+  fsType = lib.mkForce "btrfs";
+  options = [
+    "compress=zstd"
+    "noatime"
+  ];
+};
 </nowiki>}}