From cb8f383995a98768f53194361bc88506ee07c73e Mon Sep 17 00:00:00 2001
From: Josh Buker <git-commit@joshbuker.com>
Date: Mon, 26 Jan 2026 15:32:14 -0800
Subject: [PATCH 01/12] Add ODroid M1

Based on @KhashayarDanesh's work in #1269, which is also based on the
work of @sstent and @povik.

Closes #1269
---
 README.md                                     |  1 +
 flake.nix                                     |  1 +
 hardkernel/odroid-m1/default.nix              | 31 ++++++++
 hardkernel/odroid-m1/kboot-conf/default.nix   | 73 ++++++++++++++++++
 .../kboot-conf/generate-kboot-conf.sh         | 76 +++++++++++++++++++
 5 files changed, 182 insertions(+)
 create mode 100644 hardkernel/odroid-m1/default.nix
 create mode 100644 hardkernel/odroid-m1/kboot-conf/default.nix
 create mode 100644 hardkernel/odroid-m1/kboot-conf/generate-kboot-conf.sh

diff --git a/README.md b/README.md
index 4c9bcb8..4f7d2e2 100644
--- a/README.md
+++ b/README.md
@@ -400,6 +400,7 @@ See code for all available configurations.
 | [Hardkernel Odroid HC4](hardkernel/odroid-hc4/default.nix)                        | `<nixos-hardware/hardkernel/odroid-hc4>`                | `hardkernel-odroid-hc4`                |
 | [Hardkernel Odroid H3](hardkernel/odroid-h3/default.nix)                          | `<nixos-hardware/hardkernel/odroid-h3>`                 | `hardkernel-odroid-h3`                 |
 | [Hardkernel Odroid H4](hardkernel/odroid-h4/default.nix)                          | `<nixos-hardware/hardkernel/odroid-h4>`                 | `hardkernel-odroid-h4`                 |
+| [Hardkernel Odroid M1](hardkernel/odroid-m1/default.nix)                          | `<nixos-hardware/hardkernel/odroid-m1>`                 | `hardkernel-odroid-m1`                 |
 | [Olimex TERES-I](olimex/teres_i)                                                  | `<nixos-hardware/olimex/teres_i>`                       | `olimex-teres_i`                       |
 | [Omen 14-fb0798ng](omen/14-fb0798ng)                                              | `<nixos-hardware/omen/14-fb0798ng>`                     | `omen-14-fb0798ng`                     |
 | [Omen 15-ce002ns](omen/15-ce002ns)                                                | `<nixos-hardware/omen/15-ce002ns>`                      | `omen-15-ce002ns`                      |
diff --git a/flake.nix b/flake.nix
index eade087..46f0e54 100644
--- a/flake.nix
+++ b/flake.nix
@@ -374,6 +374,7 @@
           hardkernel-odroid-hc4 = import ./hardkernel/odroid-hc4;
           hardkernel-odroid-h3 = import ./hardkernel/odroid-h3;
           hardkernel-odroid-h4 = import ./hardkernel/odroid-h4;
+          hardkernel-odroid-m1 = import ./hardkernel/odroid-m1;
           omen-14-fb0798ng = import ./omen/14-fb0798ng;
           omen-15-ce002ns = import ./omen/15-ce002ns;
           omen-15-en0010ca = import ./omen/15-en0010ca;
diff --git a/hardkernel/odroid-m1/default.nix b/hardkernel/odroid-m1/default.nix
new file mode 100644
index 0000000..067c50a
--- /dev/null
+++ b/hardkernel/odroid-m1/default.nix
@@ -0,0 +1,31 @@
+# Based on kboot-conf by original authors povik and sstent.
+# I'm just porting things over. the original work can be viewed at:
+# https://github.com/sstent/nixos-on-odroid-m1
+# https://github.com/povik/nixos-on-odroid-n2
+{ config, pkgs, lib, ... }:
+
+{
+  imports = [
+    ./kboot-conf
+  ];
+
+  #boot.loader.grub.enable = false;
+  boot.loader.kboot-conf.enable = true;
+  # Use kernel >6.6 The devicetree is missing from kernel versions older than this.
+  boot.kernelPackages = lib.mkIf (lib.versionOlder pkgs.linux.version "6.6") (lib.mkDefault pkgs.linuxPackages_latest);
+  boot.supportedFilesystems = lib.mkForce ["btrfs" "cifs" "f2fs" "jfs" "ntfs" "reiserfs" "vfat" "xfs"];
+  # I'm not completely sure if some of these could be omitted,
+  # but want to make sure disk access works
+  boot.initrd.availableKernelModules = [
+    "nvme"
+    "nvme-core"
+    "phy-rockchip-naneng-combphy"
+    "phy-rockchip-snps-pcie3"
+  ];
+
+  # Petitboot uses this port and baud rate on the boards serial port,
+  # it's probably good to keep the options same for the running
+  # kernel for serial console access to work well
+  boot.kernelParams = ["console=ttyS2,1500000"];
+  hardware.deviceTree.name = "rockchip/rk3568-odroid-m1.dtb";
+}
diff --git a/hardkernel/odroid-m1/kboot-conf/default.nix b/hardkernel/odroid-m1/kboot-conf/default.nix
new file mode 100644
index 0000000..9d714a0
--- /dev/null
+++ b/hardkernel/odroid-m1/kboot-conf/default.nix
@@ -0,0 +1,73 @@
+{ config, lib, pkgs, ... }:
+
+let
+  cfg = config.boot.loader.kboot-conf;
+
+  # The builder used to write during system activation
+  builder = pkgs.replaceVarsWith {
+    src = ./generate-kboot-conf.sh;
+    replacements = {
+      bash = pkgs.bash;
+      path = lib.makeBinPath [
+        pkgs.coreutils
+        pkgs.gnused
+        pkgs.gnugrep
+      ];
+    };
+    name = "system-activation-generate-kboot-conf";
+    isExecutable = true;
+  };
+  # The builder exposed in populateCmd, which runs when building the sdImage
+  populateBuilder = pkgs.buildPackages.replaceVarsWith {
+    src = ./generate-kboot-conf.sh;
+    replacements = {
+      bash = pkgs.buildPackages.bash;
+      path = lib.makeBinPath [
+        pkgs.buildPackages.coreutils
+        pkgs.buildPackages.gnused
+        pkgs.buildPackages.gnugrep
+      ];
+    };
+    name = "build-image-generate-kboot-conf";
+    isExecutable = true;
+  };
+in
+{
+  options = {
+    boot.loader.kboot-conf = {
+      enable = lib.mkOption {
+        default = false;
+        type = lib.types.bool;
+        description = ''
+          Whether to create petitboot-compatible /kboot.conf
+        '';
+      };
+      configurationLimit = lib.mkOption {
+        default = 10;
+        example = 5;
+        type = lib.types.int;
+        description = ''
+          Maximum number of configurations in the generated kboot.conf.
+        '';
+      };
+      populateCmd = lib.mkOption {
+        type = lib.types.str;
+        readOnly = true;
+        description = ''
+          Contains the builder command used to populate an image,
+          honoring all options except the <literal>-c &lt;path-to-default-configuration&gt;</literal>
+          argument.
+          Useful to have for sdImage.populateRootCommands
+        '';
+      };
+    };
+  };
+  config = let
+    args = "-g ${toString cfg.configurationLimit} -n ${config.hardware.deviceTree.name}";
+  in
+    lib.mkIf cfg.enable {
+      system.build.installBootLoader = lib.mkForce "${builder} ${args} -c";
+      system.boot.loader.id = "kboot-conf";
+      boot.loader.kboot-conf.populateCmd = "${populateBuilder} ${args}";
+    };
+}
diff --git a/hardkernel/odroid-m1/kboot-conf/generate-kboot-conf.sh b/hardkernel/odroid-m1/kboot-conf/generate-kboot-conf.sh
new file mode 100644
index 0000000..b1f9ad7
--- /dev/null
+++ b/hardkernel/odroid-m1/kboot-conf/generate-kboot-conf.sh
@@ -0,0 +1,76 @@
+#! @bash@/bin/bash -e
+
+shopt -s nullglob
+
+export PATH="/empty:@path@"
+
+usage() {
+    echo "usage: $0 -c <path-to-default-configuration> -n <dtbName> [-g <num-generations>] [-d <target>]" >&2
+    exit 1
+}
+
+target=/kboot.conf
+default=                # Default configuration
+numGenerations=0        # Number of other generations to include in the menu
+
+while getopts "t:c:d:g:n:" opt; do
+    case "$opt" in
+        c) default="$OPTARG" ;;
+        g) numGenerations="$OPTARG" ;;
+        d) target="$OPTARG" ;;
+        n) dtbName="$OPTARG" ;;
+        \?) usage ;;
+    esac
+done
+
+[ "$default" = "" -o "$dtbName" = "" ] && usage
+
+tmp=$target.tmp
+
+# Echo out an kboot.conf menu entry
+addEntry() {
+    local path=$(readlink -f "$1")
+    local tag="$2" # Generation number or 'default'
+
+    if ! test -e $path/kernel -a -e $path/initrd; then
+        return
+    fi
+
+    timestampEpoch=$(stat -L -c '%Z' $path)
+    timestamp=$(date "+%Y-%m-%d %H:%M" -d @$timestampEpoch)
+    nixosLabel="$(cat $path/nixos-version)"
+    extraParams="$(cat $path/kernel-params)"
+
+    local kernel=$(readlink -f "$path/kernel")
+    local initrd=$(readlink -f "$path/initrd")
+    local dtbs=$(readlink -f "$path/dtbs")
+
+    local id="nixos-$tag--$nixosLabel"
+
+    if [ "$tag" = "default" ]; then
+        echo "default=$id"
+    fi
+
+    echo -n "$id='"
+    echo -n "$kernel initrd=$initrd dtb=$dtbs/$dtbName "
+    echo -n "systemConfig=$path init=$path/init $extraParams"
+    echo "'"
+}
+
+echo "# Auto-generated by generate-kboot-conf.sh, do not edit" > $tmp
+addEntry $default default >> $tmp
+
+if [ "$numGenerations" -gt 0 ]; then
+    # Add up to $numGenerations generations of the system profile to the menu,
+    # in reverse (most recent to least recent) order.
+    for generation in $(
+            (cd /nix/var/nix/profiles && ls -d system-*-link) \
+            | sed 's/system-\([0-9]\+\)-link/\1/' \
+            | sort -n -r \
+            | head -n $numGenerations); do
+        link=/nix/var/nix/profiles/system-$generation-link
+        addEntry $link $generation
+    done >> $tmp
+fi
+
+mv -f $tmp $target

From 1e1205f6f7664cd900d4f3946570a5f9ee979fbc Mon Sep 17 00:00:00 2001
From: Josh Buker <git-commit@joshbuker.com>
Date: Wed, 28 Jan 2026 22:53:01 -0800
Subject: [PATCH 02/12] Rename kboot-conf to petitboot and simplify a few
 things

---
 hardkernel/odroid-m1/default.nix              | 35 +++++----
 hardkernel/odroid-m1/kboot-conf/default.nix   | 73 ------------------
 hardkernel/odroid-m1/petitboot/default.nix    | 75 +++++++++++++++++++
 .../install-petitboot.sh}                     |  2 +-
 4 files changed, 96 insertions(+), 89 deletions(-)
 delete mode 100644 hardkernel/odroid-m1/kboot-conf/default.nix
 create mode 100644 hardkernel/odroid-m1/petitboot/default.nix
 rename hardkernel/odroid-m1/{kboot-conf/generate-kboot-conf.sh => petitboot/install-petitboot.sh} (96%)

diff --git a/hardkernel/odroid-m1/default.nix b/hardkernel/odroid-m1/default.nix
index 067c50a..bde34d4 100644
--- a/hardkernel/odroid-m1/default.nix
+++ b/hardkernel/odroid-m1/default.nix
@@ -1,31 +1,36 @@
-# Based on kboot-conf by original authors povik and sstent.
-# I'm just porting things over. the original work can be viewed at:
-# https://github.com/sstent/nixos-on-odroid-m1
-# https://github.com/povik/nixos-on-odroid-n2
 { config, pkgs, lib, ... }:
 
 {
   imports = [
-    ./kboot-conf
+    ./petitboot
   ];
 
-  #boot.loader.grub.enable = false;
-  boot.loader.kboot-conf.enable = true;
+  boot.loader.petitboot.enable = lib.mkForce true;
+
+  # Fails to rebuild unless grub is explicitly disabled
+  boot.loader.grub.enable = lib.mkForce false;
+
+  # TODO: Can this be removed? Presumably anything built with 25.11 / unstable
+  #       or later will be on a kernel >6.6
   # Use kernel >6.6 The devicetree is missing from kernel versions older than this.
   boot.kernelPackages = lib.mkIf (lib.versionOlder pkgs.linux.version "6.6") (lib.mkDefault pkgs.linuxPackages_latest);
+
+  # TODO: Debug why removing this breaks booting from petitboot
   boot.supportedFilesystems = lib.mkForce ["btrfs" "cifs" "f2fs" "jfs" "ntfs" "reiserfs" "vfat" "xfs"];
-  # I'm not completely sure if some of these could be omitted,
-  # but want to make sure disk access works
+
+  # TODO: Some of these could potentially be omitted, check which ones are
+  #       actually necessary for disk access to function
   boot.initrd.availableKernelModules = [
+    # Only nvme emitted when using nixos-generate-config on my odroid-m1
     "nvme"
-    "nvme-core"
-    "phy-rockchip-naneng-combphy"
-    "phy-rockchip-snps-pcie3"
+    # "nvme-core"
+    # "phy-rockchip-naneng-combphy"
+    # "phy-rockchip-snps-pcie3"
   ];
 
-  # Petitboot uses this port and baud rate on the boards serial port,
-  # it's probably good to keep the options same for the running
-  # kernel for serial console access to work well
+  # Petitboot uses this port and baud rate on the board's serial port. It's
+  # probably good to keep the options same for the running kernel for serial
+  # console access to work well.
   boot.kernelParams = ["console=ttyS2,1500000"];
   hardware.deviceTree.name = "rockchip/rk3568-odroid-m1.dtb";
 }
diff --git a/hardkernel/odroid-m1/kboot-conf/default.nix b/hardkernel/odroid-m1/kboot-conf/default.nix
deleted file mode 100644
index 9d714a0..0000000
--- a/hardkernel/odroid-m1/kboot-conf/default.nix
+++ /dev/null
@@ -1,73 +0,0 @@
-{ config, lib, pkgs, ... }:
-
-let
-  cfg = config.boot.loader.kboot-conf;
-
-  # The builder used to write during system activation
-  builder = pkgs.replaceVarsWith {
-    src = ./generate-kboot-conf.sh;
-    replacements = {
-      bash = pkgs.bash;
-      path = lib.makeBinPath [
-        pkgs.coreutils
-        pkgs.gnused
-        pkgs.gnugrep
-      ];
-    };
-    name = "system-activation-generate-kboot-conf";
-    isExecutable = true;
-  };
-  # The builder exposed in populateCmd, which runs when building the sdImage
-  populateBuilder = pkgs.buildPackages.replaceVarsWith {
-    src = ./generate-kboot-conf.sh;
-    replacements = {
-      bash = pkgs.buildPackages.bash;
-      path = lib.makeBinPath [
-        pkgs.buildPackages.coreutils
-        pkgs.buildPackages.gnused
-        pkgs.buildPackages.gnugrep
-      ];
-    };
-    name = "build-image-generate-kboot-conf";
-    isExecutable = true;
-  };
-in
-{
-  options = {
-    boot.loader.kboot-conf = {
-      enable = lib.mkOption {
-        default = false;
-        type = lib.types.bool;
-        description = ''
-          Whether to create petitboot-compatible /kboot.conf
-        '';
-      };
-      configurationLimit = lib.mkOption {
-        default = 10;
-        example = 5;
-        type = lib.types.int;
-        description = ''
-          Maximum number of configurations in the generated kboot.conf.
-        '';
-      };
-      populateCmd = lib.mkOption {
-        type = lib.types.str;
-        readOnly = true;
-        description = ''
-          Contains the builder command used to populate an image,
-          honoring all options except the <literal>-c &lt;path-to-default-configuration&gt;</literal>
-          argument.
-          Useful to have for sdImage.populateRootCommands
-        '';
-      };
-    };
-  };
-  config = let
-    args = "-g ${toString cfg.configurationLimit} -n ${config.hardware.deviceTree.name}";
-  in
-    lib.mkIf cfg.enable {
-      system.build.installBootLoader = lib.mkForce "${builder} ${args} -c";
-      system.boot.loader.id = "kboot-conf";
-      boot.loader.kboot-conf.populateCmd = "${populateBuilder} ${args}";
-    };
-}
diff --git a/hardkernel/odroid-m1/petitboot/default.nix b/hardkernel/odroid-m1/petitboot/default.nix
new file mode 100644
index 0000000..48c395a
--- /dev/null
+++ b/hardkernel/odroid-m1/petitboot/default.nix
@@ -0,0 +1,75 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+
+let
+  cfg = config.boot.loader.petitboot;
+  args = "-g ${toString cfg.configurationLimit} -n ${config.hardware.deviceTree.name}";
+
+  # The installer used when running nixos-rebuild switch or similar
+  installer = pkgs.replaceVarsWith {
+    src = ./install-petitboot.sh;
+    replacements = {
+      bash = pkgs.bash;
+      path = lib.makeBinPath [
+        pkgs.coreutils
+        pkgs.gnused
+        pkgs.gnugrep
+      ];
+    };
+    name = "install-petitboot";
+    isExecutable = true;
+  };
+  # The installer used to write to SD card images
+  sdImageInstaller = pkgs.buildPackages.replaceVarsWith {
+    src = ./install-petitboot.sh;
+    replacements = {
+      bash = pkgs.buildPackages.bash;
+      path = lib.makeBinPath [
+        pkgs.buildPackages.coreutils
+        pkgs.buildPackages.gnused
+        pkgs.buildPackages.gnugrep
+      ];
+    };
+    name = "install-petitboot-sd-image";
+    isExecutable = true;
+  };
+in
+{
+  options = {
+    boot.loader.petitboot = {
+      enable = lib.mkOption {
+        default = false;
+        type = lib.types.bool;
+        description = ''
+          Whether to enable the Petitboot bootloader.
+        '';
+      };
+
+      configurationLimit = lib.mkOption {
+        default = 10;
+        example = 5;
+        type = lib.types.int;
+        description = ''
+          Maximum number of configurations to display when booting.
+        '';
+      };
+    };
+  };
+
+  config = lib.mkMerge[
+    (lib.mkIf config.boot.loader.petitboot.enable {
+      system.build.installBootLoader = lib.mkForce "${installer} ${args} -c";
+      system.boot.loader.id = "petitboot";
+    })
+
+    (lib.mkIf config.boot.loader.petitboot.enable && options ? sdImage {
+      sdImage.populateRootCommands = lib.mkForce ''
+        ${sdImageInstaller} ${args} -c ${config.system.build.toplevel} -d ./files/kboot.conf
+      ''
+    })
+  ];
+}
diff --git a/hardkernel/odroid-m1/kboot-conf/generate-kboot-conf.sh b/hardkernel/odroid-m1/petitboot/install-petitboot.sh
similarity index 96%
rename from hardkernel/odroid-m1/kboot-conf/generate-kboot-conf.sh
rename to hardkernel/odroid-m1/petitboot/install-petitboot.sh
index b1f9ad7..86a0011 100644
--- a/hardkernel/odroid-m1/kboot-conf/generate-kboot-conf.sh
+++ b/hardkernel/odroid-m1/petitboot/install-petitboot.sh
@@ -57,7 +57,7 @@ addEntry() {
     echo "'"
 }
 
-echo "# Auto-generated by generate-kboot-conf.sh, do not edit" > $tmp
+echo "# Auto-generated by install-petitboot.sh, do not edit or remove" > $tmp
 addEntry $default default >> $tmp
 
 if [ "$numGenerations" -gt 0 ]; then

From 8c162f25a7b0f813954d576c88e861d1aaf57de1 Mon Sep 17 00:00:00 2001
From: Josh Buker <git-commit@joshbuker.com>
Date: Wed, 28 Jan 2026 22:56:22 -0800
Subject: [PATCH 03/12] Fix missing parenthesis

---
 hardkernel/odroid-m1/petitboot/default.nix | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hardkernel/odroid-m1/petitboot/default.nix b/hardkernel/odroid-m1/petitboot/default.nix
index 48c395a..38b2f9e 100644
--- a/hardkernel/odroid-m1/petitboot/default.nix
+++ b/hardkernel/odroid-m1/petitboot/default.nix
@@ -66,7 +66,7 @@ in
       system.boot.loader.id = "petitboot";
     })
 
-    (lib.mkIf config.boot.loader.petitboot.enable && options ? sdImage {
+    (lib.mkIf (config.boot.loader.petitboot.enable && options ? sdImage) {
       sdImage.populateRootCommands = lib.mkForce ''
         ${sdImageInstaller} ${args} -c ${config.system.build.toplevel} -d ./files/kboot.conf
       ''

From a92d980a1865e90e6830f0260d0c8d4a3b80d5c1 Mon Sep 17 00:00:00 2001
From: Josh Buker <git-commit@joshbuker.com>
Date: Wed, 28 Jan 2026 22:57:11 -0800
Subject: [PATCH 04/12] Fix missing curly brace

---
 hardkernel/odroid-m1/petitboot/default.nix | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hardkernel/odroid-m1/petitboot/default.nix b/hardkernel/odroid-m1/petitboot/default.nix
index 38b2f9e..ab37b1f 100644
--- a/hardkernel/odroid-m1/petitboot/default.nix
+++ b/hardkernel/odroid-m1/petitboot/default.nix
@@ -69,7 +69,7 @@ in
     (lib.mkIf (config.boot.loader.petitboot.enable && options ? sdImage) {
       sdImage.populateRootCommands = lib.mkForce ''
         ${sdImageInstaller} ${args} -c ${config.system.build.toplevel} -d ./files/kboot.conf
-      ''
+      '';
     })
   ];
 }

From c281bd071aa68dc67abb6e0c6db561362a0edf49 Mon Sep 17 00:00:00 2001
From: Josh Buker <git-commit@joshbuker.com>
Date: Wed, 28 Jan 2026 22:59:36 -0800
Subject: [PATCH 05/12] Try rawdogging sdImage and see if it breaks
 nixos-rebuild switch

---
 hardkernel/odroid-m1/petitboot/default.nix | 19 +++++++------------
 1 file changed, 7 insertions(+), 12 deletions(-)

diff --git a/hardkernel/odroid-m1/petitboot/default.nix b/hardkernel/odroid-m1/petitboot/default.nix
index ab37b1f..38ff43e 100644
--- a/hardkernel/odroid-m1/petitboot/default.nix
+++ b/hardkernel/odroid-m1/petitboot/default.nix
@@ -60,16 +60,11 @@ in
     };
   };
 
-  config = lib.mkMerge[
-    (lib.mkIf config.boot.loader.petitboot.enable {
-      system.build.installBootLoader = lib.mkForce "${installer} ${args} -c";
-      system.boot.loader.id = "petitboot";
-    })
-
-    (lib.mkIf (config.boot.loader.petitboot.enable && options ? sdImage) {
-      sdImage.populateRootCommands = lib.mkForce ''
-        ${sdImageInstaller} ${args} -c ${config.system.build.toplevel} -d ./files/kboot.conf
-      '';
-    })
-  ];
+  config = lib.mkIf config.boot.loader.petitboot.enable {
+    system.build.installBootLoader = lib.mkForce "${installer} ${args} -c";
+    system.boot.loader.id = "petitboot";
+    sdImage.populateRootCommands = lib.mkForce ''
+      ${sdImageInstaller} ${args} -c ${config.system.build.toplevel} -d ./files/kboot.conf
+    '';
+  };
 }

From d6aea43451f0c381cdb4efdad2328006c1ae459e Mon Sep 17 00:00:00 2001
From: Josh Buker <git-commit@joshbuker.com>
Date: Wed, 28 Jan 2026 23:09:47 -0800
Subject: [PATCH 06/12] Unfortunately, that does break nixos-rebuild switch

---
 hardkernel/odroid-m1/petitboot/default.nix | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/hardkernel/odroid-m1/petitboot/default.nix b/hardkernel/odroid-m1/petitboot/default.nix
index 38ff43e..6de0093 100644
--- a/hardkernel/odroid-m1/petitboot/default.nix
+++ b/hardkernel/odroid-m1/petitboot/default.nix
@@ -57,14 +57,21 @@ in
           Maximum number of configurations to display when booting.
         '';
       };
+
+      populateCmd = lib.mkOption {
+        type = lib.types.str;
+        readOnly = true;
+        description = ''
+          Contains the script used to populate petitboot when building an image.
+          Primarily used for sdImage.populateRootCommands.
+        '';
+      };
     };
   };
 
-  config = lib.mkIf config.boot.loader.petitboot.enable {
+  config = lib.mkIf cfg.enable {
     system.build.installBootLoader = lib.mkForce "${installer} ${args} -c";
     system.boot.loader.id = "petitboot";
-    sdImage.populateRootCommands = lib.mkForce ''
-      ${sdImageInstaller} ${args} -c ${config.system.build.toplevel} -d ./files/kboot.conf
-    '';
+    cfg.populateCmd = "${sdImageInstaller} ${args}";
   };
 }

From 719a89028dbf07cd432e867bf14810e2b23cb1ce Mon Sep 17 00:00:00 2001
From: Josh Buker <git-commit@joshbuker.com>
Date: Wed, 28 Jan 2026 23:15:11 -0800
Subject: [PATCH 07/12] Apparently aliases are read-only

---
 hardkernel/odroid-m1/petitboot/default.nix | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hardkernel/odroid-m1/petitboot/default.nix b/hardkernel/odroid-m1/petitboot/default.nix
index 6de0093..f4a7535 100644
--- a/hardkernel/odroid-m1/petitboot/default.nix
+++ b/hardkernel/odroid-m1/petitboot/default.nix
@@ -72,6 +72,6 @@ in
   config = lib.mkIf cfg.enable {
     system.build.installBootLoader = lib.mkForce "${installer} ${args} -c";
     system.boot.loader.id = "petitboot";
-    cfg.populateCmd = "${sdImageInstaller} ${args}";
+    boot.loader.petitboot.populateCmd = "${sdImageInstaller} ${args}";
   };
 }

From 53702e58b4c879f395dff190b3a4301dc3104883 Mon Sep 17 00:00:00 2001
From: Josh Buker <git-commit@joshbuker.com>
Date: Wed, 28 Jan 2026 23:18:19 -0800
Subject: [PATCH 08/12] Appease nixfmt

---
 hardkernel/odroid-m1/default.nix | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/hardkernel/odroid-m1/default.nix b/hardkernel/odroid-m1/default.nix
index bde34d4..f5977b5 100644
--- a/hardkernel/odroid-m1/default.nix
+++ b/hardkernel/odroid-m1/default.nix
@@ -16,7 +16,16 @@
   boot.kernelPackages = lib.mkIf (lib.versionOlder pkgs.linux.version "6.6") (lib.mkDefault pkgs.linuxPackages_latest);
 
   # TODO: Debug why removing this breaks booting from petitboot
-  boot.supportedFilesystems = lib.mkForce ["btrfs" "cifs" "f2fs" "jfs" "ntfs" "reiserfs" "vfat" "xfs"];
+  boot.supportedFilesystems = lib.mkForce [
+    "btrfs"
+    "cifs"
+    "f2fs"
+    "jfs"
+    "ntfs"
+    "reiserfs"
+    "vfat"
+    "xfs"
+  ];
 
   # TODO: Some of these could potentially be omitted, check which ones are
   #       actually necessary for disk access to function
@@ -31,6 +40,6 @@
   # Petitboot uses this port and baud rate on the board's serial port. It's
   # probably good to keep the options same for the running kernel for serial
   # console access to work well.
-  boot.kernelParams = ["console=ttyS2,1500000"];
+  boot.kernelParams = [ "console=ttyS2,1500000" ];
   hardware.deviceTree.name = "rockchip/rk3568-odroid-m1.dtb";
 }

From 0cb7e0bcab6946fb42e11dbcffc882af8c25b767 Mon Sep 17 00:00:00 2001
From: Josh Buker <git-commit@joshbuker.com>
Date: Wed, 28 Jan 2026 23:25:11 -0800
Subject: [PATCH 09/12] Try removing kernelPackages and supportedFilesystems
 overrides

---
 hardkernel/odroid-m1/default.nix | 22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/hardkernel/odroid-m1/default.nix b/hardkernel/odroid-m1/default.nix
index f5977b5..e055b93 100644
--- a/hardkernel/odroid-m1/default.nix
+++ b/hardkernel/odroid-m1/default.nix
@@ -13,19 +13,19 @@
   # TODO: Can this be removed? Presumably anything built with 25.11 / unstable
   #       or later will be on a kernel >6.6
   # Use kernel >6.6 The devicetree is missing from kernel versions older than this.
-  boot.kernelPackages = lib.mkIf (lib.versionOlder pkgs.linux.version "6.6") (lib.mkDefault pkgs.linuxPackages_latest);
+  # boot.kernelPackages = lib.mkIf (lib.versionOlder pkgs.linux.version "6.6") (lib.mkDefault pkgs.linuxPackages_latest);
 
   # TODO: Debug why removing this breaks booting from petitboot
-  boot.supportedFilesystems = lib.mkForce [
-    "btrfs"
-    "cifs"
-    "f2fs"
-    "jfs"
-    "ntfs"
-    "reiserfs"
-    "vfat"
-    "xfs"
-  ];
+  # boot.supportedFilesystems = lib.mkForce [
+  #   "btrfs"
+  #   "cifs"
+  #   "f2fs"
+  #   "jfs"
+  #   "ntfs"
+  #   "reiserfs"
+  #   "vfat"
+  #   "xfs"
+  # ];
 
   # TODO: Some of these could potentially be omitted, check which ones are
   #       actually necessary for disk access to function

From d2907ab4462ee840ac2ddd070f40c48555c2dc2f Mon Sep 17 00:00:00 2001
From: Josh Buker <git-commit@joshbuker.com>
Date: Thu, 29 Jan 2026 00:06:32 -0800
Subject: [PATCH 10/12] Remove unnecessary configuration for odroid-m1

---
 hardkernel/odroid-m1/default.nix | 36 ++++++++++----------------------
 1 file changed, 11 insertions(+), 25 deletions(-)

diff --git a/hardkernel/odroid-m1/default.nix b/hardkernel/odroid-m1/default.nix
index e055b93..e3db31e 100644
--- a/hardkernel/odroid-m1/default.nix
+++ b/hardkernel/odroid-m1/default.nix
@@ -1,40 +1,23 @@
-{ config, pkgs, lib, ... }:
+{
+  config,
+  pkgs,
+  lib,
+  ...
+}:
 
 {
   imports = [
     ./petitboot
   ];
 
+  # Enable petitboot support.
   boot.loader.petitboot.enable = lib.mkForce true;
 
-  # Fails to rebuild unless grub is explicitly disabled
+  # `nixos-rebuild` fails unless grub is explicitly disabled.
   boot.loader.grub.enable = lib.mkForce false;
 
-  # TODO: Can this be removed? Presumably anything built with 25.11 / unstable
-  #       or later will be on a kernel >6.6
-  # Use kernel >6.6 The devicetree is missing from kernel versions older than this.
-  # boot.kernelPackages = lib.mkIf (lib.versionOlder pkgs.linux.version "6.6") (lib.mkDefault pkgs.linuxPackages_latest);
-
-  # TODO: Debug why removing this breaks booting from petitboot
-  # boot.supportedFilesystems = lib.mkForce [
-  #   "btrfs"
-  #   "cifs"
-  #   "f2fs"
-  #   "jfs"
-  #   "ntfs"
-  #   "reiserfs"
-  #   "vfat"
-  #   "xfs"
-  # ];
-
-  # TODO: Some of these could potentially be omitted, check which ones are
-  #       actually necessary for disk access to function
   boot.initrd.availableKernelModules = [
-    # Only nvme emitted when using nixos-generate-config on my odroid-m1
     "nvme"
-    # "nvme-core"
-    # "phy-rockchip-naneng-combphy"
-    # "phy-rockchip-snps-pcie3"
   ];
 
   # Petitboot uses this port and baud rate on the board's serial port. It's
@@ -42,4 +25,7 @@
   # console access to work well.
   boot.kernelParams = [ "console=ttyS2,1500000" ];
   hardware.deviceTree.name = "rockchip/rk3568-odroid-m1.dtb";
+  # FIXME: The serial terminal does seem to throw random errors still, but that
+  #        doesn't appear to crash anything. May need adjusted if you're
+  #        actually using the GPIO.
 }

From 21deaf7ac994cf87d2a70f8616f8fe846809c2eb Mon Sep 17 00:00:00 2001
From: Josh Buker <git-commit@joshbuker.com>
Date: Mon, 9 Feb 2026 15:51:54 -0800
Subject: [PATCH 11/12] Add README.md to ODroid M1 per feedback

---
 hardkernel/odroid-m1/README.md | 208 +++++++++++++++++++++++++++++++++
 1 file changed, 208 insertions(+)
 create mode 100644 hardkernel/odroid-m1/README.md

diff --git a/hardkernel/odroid-m1/README.md b/hardkernel/odroid-m1/README.md
new file mode 100644
index 0000000..e841cfe
--- /dev/null
+++ b/hardkernel/odroid-m1/README.md
@@ -0,0 +1,208 @@
+# ODroid M1
+
+Hardware support for the Hardkernel ODroid M1: https://www.hardkernel.com/shop/odroid-m1-with-8gbyte-ram/
+
+## Initial Installation
+
+This is for creating the initial image used to install to the SD Card or NVM Drive.
+
+Example `flake.nix`:
+
+```nix
+{
+  description = "SD Card Image Generator for ODroid M1";
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
+    nixos-hardware.url = "github:nixos/nixos-hardware/master";
+  };
+  outputs = { self, nixpkgs, nixos-hardware }: rec {
+    nixosConfigurations.m1 = nixpkgs.lib.nixosSystem {
+      modules = [
+        "${nixpkgs}/nixos/modules/installer/sd-card/sd-image-aarch64.nix"
+        nixos-hardware.nixosModules.hardkernel-odroid-m1
+        ./sdimageconfiguration.nix
+        {
+          nixpkgs.config.allowUnsupportedSystem = true;
+          nixpkgs.hostPlatform.system = "aarch64-linux";
+          nixpkgs.buildPlatform.system = "x86_64-linux"; # If you build on x86 otherwise change this.
+        }
+      ];
+    };
+    images.m1 = nixosConfigurations.m1.config.system.build.sdImage;
+  };
+}
+```
+
+For building the initial sd card image, you can use this example (tweaked for your preferences) `sdimageconfiguration.nix`:
+
+```nix
+{ config, pkgs, lib, ... }:
+
+{
+  system.stateVersion = lib.mkDefault "25.11";
+  nixpkgs.hostPlatform.system = "aarch64-linux";
+
+  sdImage = {
+    # Skip compression, we'll want the img uncompressed for flashing anyway
+    compressImage = false;
+    # The system will not boot if this is missing
+    populateRootCommands = ''
+      ${config.boot.loader.petitboot.populateCmd} -c ${config.system.build.toplevel} -d ./files/kboot.conf
+    '';
+  };
+
+  services.openssh = {
+    enable = true;
+    settings = {
+      # Highly recommended: Set Password Authentication to false if you have authorized keys you can use. This is an insecure default
+      PasswordAuthentication = true;
+      PermitRootLogin = "no";
+      AllowUsers = [ "odroid" ];
+    };
+  };
+
+  # You will almost certainly want Git to pull in your configuration repository
+  environment.systemPackages = [
+    pkgs.git
+  ];
+
+  users.users.odroid = {
+    isNormalUser = true;
+    description = "Default User";
+    extraGroups = [ "networkmanager" "wheel" ];
+    packages = [];
+    # Highly recommended: Change this default password using `sudo passwd` after logging in
+    initialPassword = lib.mkForce "odroid";
+    # You can find this from https://github.com/username.keys for example
+    openssh.authorizedKeys.keys = [];
+  };
+}
+```
+
+Put both of these files into a Git repo, and build with:
+
+```sh
+nix build .#images.m1
+```
+
+## Ongoing updates
+
+To your NixOS server flake, you'll want to ensure that the host is set to aarch64-linux.
+
+An example flake:
+
+```nix
+{
+  description = "My NixOS configuration flake";
+
+  inputs = {
+    # Nixpkgs - Stable 25.11 release
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.11";
+    # Home Manager - Stable 25.11 release
+    home-manager.url = "github:nix-community/home-manager/release-25.11";
+    home-manager.inputs.nixpkgs.follows = "nixpkgs";
+    # NixOS Hardware
+    nixos-hardware.url = "github:nixos/nixos-hardware/master";
+  };
+
+  outputs = {
+    self,
+    nixpkgs,
+    home-manager,
+    nixos-hardware,
+    ...
+  }@inputs:
+
+  let
+    mkSystem = hostname: systemArchitecture: # hostname: is a positional argument
+      nixpkgs.lib.nixosSystem {
+        system = systemArchitecture;
+
+        specialArgs = { inherit inputs; };
+
+        modules = [
+          ./hosts/${hostname}/configuration.nix
+
+          home-manager.nixosModules.home-manager
+          {
+            home-manager.useGlobalPkgs = true;
+            home-manager.useUserPackages = true;
+            home-manager.backupFileExtension = "backup";
+          }
+        ];
+      };
+
+    hosts = [
+      { hostname = "other-example"; systemArchitecture = "x86_64-linux"; }
+      { hostname = "odroid-m1-example"; systemArchitecture = "aarch64-linux"; }
+    ];
+  in
+  {
+    # This is what creates the NixOS configurations for each host
+    nixosConfigurations = builtins.listToAttrs (
+      # Iterator - nixConfigurations.<name> = <value>
+      map (host: {
+        name = host.hostname;
+        value = mkSystem host.hostname host.systemArchitecture;
+      })
+      # Array to iterate over
+      hosts
+    );
+  };
+}
+```
+
+And the related `configuration.nix`:
+
+```nix
+{ config, pkgs, inputs, ... }:
+
+{
+  imports =
+    [
+      inputs.nixos-hardware.nixosModules.hardkernel-odroid-m1
+      ./hardware-configuration.nix
+      ../../modules/nix
+      ../../users
+    ];
+
+  networking.hostName = "odroid-m1-example"; # Define your hostname.
+}
+```
+
+And `hardware-configuration.nix`:
+
+```nix
+# Do not modify this file!  It was generated by ‘nixos-generate-config’
+# and may be overwritten by future invocations.  Please make changes
+# to /etc/nixos/configuration.nix instead.
+{ config, lib, pkgs, modulesPath, ... }:
+
+{
+  imports =
+    [ (modulesPath + "/installer/scan/not-detected.nix")
+    ];
+
+  boot.initrd.availableKernelModules = [ "nvme" ];
+  boot.initrd.kernelModules = [ ];
+  boot.kernelModules = [ ];
+  boot.extraModulePackages = [ ];
+
+  fileSystems."/" =
+    { device = "/dev/disk/by-uuid/44444444-4444-4444-8888-888888888888";
+      fsType = "ext4";
+    };
+
+  swapDevices = [ ];
+
+  nixpkgs.hostPlatform = lib.mkDefault "aarch64-linux";
+}
+```
+
+You can generate these default files (with a few warnings) by running the following command on the odroid after initial boot:
+
+```sh
+nixos-generate-config
+```
+
+It will save a configuration.nix and hardware-configuration.nix to `/etc/nixos`. Critically, you will need to add `inputs.nixos-hardware.nixosModules.hardkernel-odroid-m1` to the imports in `configuration.nix` for it to work.

From 001bac71322e182497ccf2c1d192e8858b8325b7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=B6rg=20Thalheim?= <joerg@thalheim.io>
Date: Sun, 15 Feb 2026 16:25:49 +0100
Subject: [PATCH 12/12] odroid-m1: simplify README

Remove opinionated configuration that doesn't belong in a hardware
module README: home-manager setup, user/SSH configuration, example
hardware-configuration.nix, and an overly complex multi-host flake
pattern.

Keep only the ODroid M1-specific information: how to build the SD card
image with the required petitboot populateRootCommands, and how to set
up the flake for ongoing nixos-rebuild switch.
---
 hardkernel/odroid-m1/README.md | 186 +++++++--------------------------
 1 file changed, 39 insertions(+), 147 deletions(-)

diff --git a/hardkernel/odroid-m1/README.md b/hardkernel/odroid-m1/README.md
index e841cfe..cb94bd9 100644
--- a/hardkernel/odroid-m1/README.md
+++ b/hardkernel/odroid-m1/README.md
@@ -2,15 +2,13 @@
 
 Hardware support for the Hardkernel ODroid M1: https://www.hardkernel.com/shop/odroid-m1-with-8gbyte-ram/
 
-## Initial Installation
+## Building an SD Card Image
 
-This is for creating the initial image used to install to the SD Card or NVM Drive.
-
-Example `flake.nix`:
+To create an initial SD card image for installation:
 
 ```nix
+# flake.nix
 {
-  description = "SD Card Image Generator for ODroid M1";
   inputs = {
     nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
     nixos-hardware.url = "github:nixos/nixos-hardware/master";
@@ -20,11 +18,11 @@ Example `flake.nix`:
       modules = [
         "${nixpkgs}/nixos/modules/installer/sd-card/sd-image-aarch64.nix"
         nixos-hardware.nixosModules.hardkernel-odroid-m1
-        ./sdimageconfiguration.nix
+        ./sdimage.nix
         {
-          nixpkgs.config.allowUnsupportedSystem = true;
           nixpkgs.hostPlatform.system = "aarch64-linux";
-          nixpkgs.buildPlatform.system = "x86_64-linux"; # If you build on x86 otherwise change this.
+          # Uncomment if cross-compiling from x86_64:
+          # nixpkgs.buildPlatform.system = "x86_64-linux";
         }
       ];
     };
@@ -33,176 +31,70 @@ Example `flake.nix`:
 }
 ```
 
-For building the initial sd card image, you can use this example (tweaked for your preferences) `sdimageconfiguration.nix`:
-
 ```nix
-{ config, pkgs, lib, ... }:
-
+# sdimage.nix
+{ config, ... }:
 {
-  system.stateVersion = lib.mkDefault "25.11";
-  nixpkgs.hostPlatform.system = "aarch64-linux";
+  imports = [ ./common.nix ];
 
   sdImage = {
-    # Skip compression, we'll want the img uncompressed for flashing anyway
     compressImage = false;
-    # The system will not boot if this is missing
+    # Required for the system to boot
     populateRootCommands = ''
       ${config.boot.loader.petitboot.populateCmd} -c ${config.system.build.toplevel} -d ./files/kboot.conf
     '';
   };
+}
+```
 
-  services.openssh = {
-    enable = true;
-    settings = {
-      # Highly recommended: Set Password Authentication to false if you have authorized keys you can use. This is an insecure default
-      PasswordAuthentication = true;
-      PermitRootLogin = "no";
-      AllowUsers = [ "odroid" ];
-    };
-  };
+```nix
+# common.nix
+{ pkgs, ... }:
+{
+  services.openssh.enable = true;
 
-  # You will almost certainly want Git to pull in your configuration repository
-  environment.systemPackages = [
-    pkgs.git
-  ];
+  environment.systemPackages = [ pkgs.git ];
 
   users.users.odroid = {
     isNormalUser = true;
-    description = "Default User";
-    extraGroups = [ "networkmanager" "wheel" ];
-    packages = [];
-    # Highly recommended: Change this default password using `sudo passwd` after logging in
-    initialPassword = lib.mkForce "odroid";
-    # You can find this from https://github.com/username.keys for example
-    openssh.authorizedKeys.keys = [];
+    extraGroups = [ "wheel" ];
+    initialPassword = "odroid";
+    # openssh.authorizedKeys.keys = [ "ssh-ed25519 AAAA..." ];
   };
 }
 ```
 
-Put both of these files into a Git repo, and build with:
+Build with:
 
 ```sh
 nix build .#images.m1
 ```
 
-## Ongoing updates
+## Ongoing Configuration
 
-To your NixOS server flake, you'll want to ensure that the host is set to aarch64-linux.
-
-An example flake:
+After booting the SD card image, run `nixos-generate-config` to generate
+`hardware-configuration.nix` for your system. Then set up your configuration
+flake:
 
 ```nix
+# flake.nix
 {
-  description = "My NixOS configuration flake";
-
   inputs = {
-    # Nixpkgs - Stable 25.11 release
-    nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.11";
-    # Home Manager - Stable 25.11 release
-    home-manager.url = "github:nix-community/home-manager/release-25.11";
-    home-manager.inputs.nixpkgs.follows = "nixpkgs";
-    # NixOS Hardware
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
     nixos-hardware.url = "github:nixos/nixos-hardware/master";
   };
-
-  outputs = {
-    self,
-    nixpkgs,
-    home-manager,
-    nixos-hardware,
-    ...
-  }@inputs:
-
-  let
-    mkSystem = hostname: systemArchitecture: # hostname: is a positional argument
-      nixpkgs.lib.nixosSystem {
-        system = systemArchitecture;
-
-        specialArgs = { inherit inputs; };
-
-        modules = [
-          ./hosts/${hostname}/configuration.nix
-
-          home-manager.nixosModules.home-manager
-          {
-            home-manager.useGlobalPkgs = true;
-            home-manager.useUserPackages = true;
-            home-manager.backupFileExtension = "backup";
-          }
-        ];
-      };
-
-    hosts = [
-      { hostname = "other-example"; systemArchitecture = "x86_64-linux"; }
-      { hostname = "odroid-m1-example"; systemArchitecture = "aarch64-linux"; }
-    ];
-  in
-  {
-    # This is what creates the NixOS configurations for each host
-    nixosConfigurations = builtins.listToAttrs (
-      # Iterator - nixConfigurations.<name> = <value>
-      map (host: {
-        name = host.hostname;
-        value = mkSystem host.hostname host.systemArchitecture;
-      })
-      # Array to iterate over
-      hosts
-    );
+  outputs = { nixpkgs, nixos-hardware, ... }: {
+    nixosConfigurations.m1 = nixpkgs.lib.nixosSystem {
+      modules = [
+        nixos-hardware.nixosModules.hardkernel-odroid-m1
+        ./common.nix
+        ./configuration.nix
+        ./hardware-configuration.nix
+      ];
+    };
   };
 }
 ```
 
-And the related `configuration.nix`:
-
-```nix
-{ config, pkgs, inputs, ... }:
-
-{
-  imports =
-    [
-      inputs.nixos-hardware.nixosModules.hardkernel-odroid-m1
-      ./hardware-configuration.nix
-      ../../modules/nix
-      ../../users
-    ];
-
-  networking.hostName = "odroid-m1-example"; # Define your hostname.
-}
-```
-
-And `hardware-configuration.nix`:
-
-```nix
-# Do not modify this file!  It was generated by ‘nixos-generate-config’
-# and may be overwritten by future invocations.  Please make changes
-# to /etc/nixos/configuration.nix instead.
-{ config, lib, pkgs, modulesPath, ... }:
-
-{
-  imports =
-    [ (modulesPath + "/installer/scan/not-detected.nix")
-    ];
-
-  boot.initrd.availableKernelModules = [ "nvme" ];
-  boot.initrd.kernelModules = [ ];
-  boot.kernelModules = [ ];
-  boot.extraModulePackages = [ ];
-
-  fileSystems."/" =
-    { device = "/dev/disk/by-uuid/44444444-4444-4444-8888-888888888888";
-      fsType = "ext4";
-    };
-
-  swapDevices = [ ];
-
-  nixpkgs.hostPlatform = lib.mkDefault "aarch64-linux";
-}
-```
-
-You can generate these default files (with a few warnings) by running the following command on the odroid after initial boot:
-
-```sh
-nixos-generate-config
-```
-
-It will save a configuration.nix and hardware-configuration.nix to `/etc/nixos`. Critically, you will need to add `inputs.nixos-hardware.nixosModules.hardkernel-odroid-m1` to the imports in `configuration.nix` for it to work.
+The module configures petitboot as the boot loader, so `nixos-rebuild switch`
+works as usual.