sd-image: Moves `/boot` into rootfs

The current FAT32 partition is kept as it is required for the Raspberry
Pi family of hardware. It is where the firmware is kept.

The partition is kept bootable, and the boot files kept in there until
the following commits, to keep all commits of this series individually
bootable.

4 files changed, 44 insertions, 43 deletions

diff --git a/nixos/modules/installer/cd-dvd/sd-image-aarch64.nix b/nixos/modules/installer/cd-dvd/sd-image-aarch64.nix
index 5f7194e92a3..eb0bc9da409 100644
--- a/nixos/modules/installer/cd-dvd/sd-image-aarch64.nix
+++ b/nixos/modules/installer/cd-dvd/sd-image-aarch64.nix
@@ -27,7 +27,7 @@ in
   boot.kernelParams = ["cma=32M" "console=ttyS0,115200n8" "console=ttyAMA0,115200n8" "console=tty0"];
 
   sdImage = {
-    populateBootCommands = let
+    populateFirmwareCommands = let
       configTxt = pkgs.writeText "config.txt" ''
         kernel=u-boot-rpi3.bin
 
@@ -43,10 +43,10 @@ in
         avoid_warnings=1
       '';
       in ''
-        (cd ${pkgs.raspberrypifw}/share/raspberrypi/boot && cp bootcode.bin fixup*.dat start*.elf $NIX_BUILD_TOP/boot/)
-        cp ${pkgs.ubootRaspberryPi3_64bit}/u-boot.bin boot/u-boot-rpi3.bin
-        cp ${configTxt} boot/config.txt
-        ${extlinux-conf-builder} -t 3 -c ${config.system.build.toplevel} -d ./boot
+        (cd ${pkgs.raspberrypifw}/share/raspberrypi/boot && cp bootcode.bin fixup*.dat start*.elf $NIX_BUILD_TOP/firmware/)
+        cp ${pkgs.ubootRaspberryPi3_64bit}/u-boot.bin firmware/u-boot-rpi3.bin
+        cp ${configTxt} firmware/config.txt
+        ${extlinux-conf-builder} -t 3 -c ${config.system.build.toplevel} -d ./firmware
       '';
   };
 }
diff --git a/nixos/modules/installer/cd-dvd/sd-image-armv7l-multiplatform.nix b/nixos/modules/installer/cd-dvd/sd-image-armv7l-multiplatform.nix
index 71448f74c36..02587ba4af0 100644
--- a/nixos/modules/installer/cd-dvd/sd-image-armv7l-multiplatform.nix
+++ b/nixos/modules/installer/cd-dvd/sd-image-armv7l-multiplatform.nix
@@ -29,7 +29,7 @@ in
   boot.kernelParams = ["console=ttyS0,115200n8" "console=ttymxc0,115200n8" "console=ttyAMA0,115200n8" "console=ttyO0,115200n8" "console=ttySAC2,115200n8" "console=tty0"];
 
   sdImage = {
-    populateBootCommands = let
+    populateFirmwareCommands = let
       configTxt = pkgs.writeText "config.txt" ''
         # Prevent the firmware from smashing the framebuffer setup done by the mainline kernel
         # when attempting to show low-voltage or overtemperature warnings.
@@ -46,11 +46,11 @@ in
         enable_uart=1
       '';
       in ''
-        (cd ${pkgs.raspberrypifw}/share/raspberrypi/boot && cp bootcode.bin fixup*.dat start*.elf $NIX_BUILD_TOP/boot/)
-        cp ${pkgs.ubootRaspberryPi2}/u-boot.bin boot/u-boot-rpi2.bin
-        cp ${pkgs.ubootRaspberryPi3_32bit}/u-boot.bin boot/u-boot-rpi3.bin
-        cp ${configTxt} boot/config.txt
-        ${extlinux-conf-builder} -t 3 -c ${config.system.build.toplevel} -d ./boot
+        (cd ${pkgs.raspberrypifw}/share/raspberrypi/boot && cp bootcode.bin fixup*.dat start*.elf $NIX_BUILD_TOP/firmware/)
+        cp ${pkgs.ubootRaspberryPi2}/u-boot.bin firmware/u-boot-rpi2.bin
+        cp ${pkgs.ubootRaspberryPi3_32bit}/u-boot.bin firmware/u-boot-rpi3.bin
+        cp ${configTxt} firmware/config.txt
+        ${extlinux-conf-builder} -t 3 -c ${config.system.build.toplevel} -d ./firmware
       '';
   };
 }
diff --git a/nixos/modules/installer/cd-dvd/sd-image-raspberrypi.nix b/nixos/modules/installer/cd-dvd/sd-image-raspberrypi.nix
index 96e06670694..de3385290d2 100644
--- a/nixos/modules/installer/cd-dvd/sd-image-raspberrypi.nix
+++ b/nixos/modules/installer/cd-dvd/sd-image-raspberrypi.nix
@@ -35,11 +35,11 @@ in
         kernel=u-boot-rpi1.bin
       '';
       in ''
-        (cd ${pkgs.raspberrypifw}/share/raspberrypi/boot && cp bootcode.bin fixup*.dat start*.elf $NIX_BUILD_TOP/boot/)
-        cp ${pkgs.ubootRaspberryPiZero}/u-boot.bin boot/u-boot-rpi0.bin
-        cp ${pkgs.ubootRaspberryPi}/u-boot.bin boot/u-boot-rpi1.bin
-        cp ${configTxt} boot/config.txt
-        ${extlinux-conf-builder} -t 3 -c ${config.system.build.toplevel} -d ./boot
+        (cd ${pkgs.raspberrypifw}/share/raspberrypi/boot && cp bootcode.bin fixup*.dat start*.elf $NIX_BUILD_TOP/firmware/)
+        cp ${pkgs.ubootRaspberryPiZero}/u-boot.bin firmware/u-boot-rpi0.bin
+        cp ${pkgs.ubootRaspberryPi}/u-boot.bin firmware/u-boot-rpi1.bin
+        cp ${configTxt} firmware/config.txt
+        ${extlinux-conf-builder} -t 3 -c ${config.system.build.toplevel} -d ./firmware
       '';
   };
 }
diff --git a/nixos/modules/installer/cd-dvd/sd-image.nix b/nixos/modules/installer/cd-dvd/sd-image.nix
index 69746a8e979..6b5bccfa2e7 100644
--- a/nixos/modules/installer/cd-dvd/sd-image.nix
+++ b/nixos/modules/installer/cd-dvd/sd-image.nix
@@ -43,12 +43,12 @@ in
       '';
     };
 
-    bootPartitionID = mkOption {
+    firmwarePartitionID = mkOption {
       type = types.string;
       default = "0x2178694e";
       description = ''
-        Volume ID for the /boot partition on the SD card. This value must be a
-        32-bit hexadecimal number.
+        Volume ID for the /boot/firmware partition on the SD card. This value
+        must be a 32-bit hexadecimal number.
       '';
     };
 
@@ -61,29 +61,30 @@ in
       '';
     };
 
-    bootSize = mkOption {
+    firmwareSize = mkOption {
       type = types.int;
       default = 120;
       description = ''
-        Size of the /boot partition, in megabytes.
+        Size of the /boot/firmware partition, in megabytes.
       '';
     };
 
-    populateBootCommands = mkOption {
-      example = literalExample "'' cp \${pkgs.myBootLoader}/u-boot.bin boot/ ''";
+    populateFirmwareCommands = mkOption {
+      example = literalExample "'' cp \${pkgs.myBootLoader}/u-boot.bin firmware/ ''";
       description = ''
-        Shell commands to populate the ./boot directory.
+        Shell commands to populate the ./firmware directory.
         All files in that directory are copied to the
-        /boot partition on the SD image.
+        /boot/firmware partition on the SD image.
       '';
     };
   };
 
   config = {
     fileSystems = {
-      "/boot" = {
-        device = "/dev/disk/by-label/NIXOS_BOOT";
+      "/boot/firmware" = {
+        device = "/dev/disk/by-label/FIRMWARE";
         fsType = "vfat";
+        options = [ "nofail" "noauto" ];
       };
       "/" = {
         device = "/dev/disk/by-label/NIXOS_SD";
@@ -105,39 +106,39 @@ in
         echo "${pkgs.stdenv.buildPlatform.system}" > $out/nix-support/system
         echo "file sd-image $img" >> $out/nix-support/hydra-build-products
 
-        # Create the image file sized to fit /boot and /, plus 20M of slack
+        # Create the image file sized to fit /boot/firmware and /, plus 20M of slack
         rootSizeBlocks=$(du -B 512 --apparent-size ${rootfsImage} | awk '{ print $1 }')
-        bootSizeBlocks=$((${toString config.sdImage.bootSize} * 1024 * 1024 / 512))
-        imageSize=$((rootSizeBlocks * 512 + bootSizeBlocks * 512 + 20 * 1024 * 1024))
+        firmwareSizeBlocks=$((${toString config.sdImage.firmwareSize} * 1024 * 1024 / 512))
+        imageSize=$((rootSizeBlocks * 512 + firmwareSizeBlocks * 512 + 20 * 1024 * 1024))
         truncate -s $imageSize $img
 
         # type=b is 'W95 FAT32', type=83 is 'Linux'.
         sfdisk $img <<EOF
             label: dos
-            label-id: ${config.sdImage.bootPartitionID}
+            label-id: ${config.sdImage.firmwarePartitionID}
 
-            start=8M, size=$bootSizeBlocks, type=b, bootable
-            start=${toString (8 + config.sdImage.bootSize)}M, type=83
+            start=8M, size=$firmwareSizeBlocks, type=b, bootable
+            start=${toString (8 + config.sdImage.firmwareSize)}M, type=83
         EOF
 
         # Copy the rootfs into the SD image
         eval $(partx $img -o START,SECTORS --nr 2 --pairs)
         dd conv=notrunc if=${rootfsImage} of=$img seek=$START count=$SECTORS
 
-        # Create a FAT32 /boot partition of suitable size into bootpart.img
+        # Create a FAT32 /boot/firmware partition of suitable size into firmware_part.img
         eval $(partx $img -o START,SECTORS --nr 1 --pairs)
-        truncate -s $((SECTORS * 512)) bootpart.img
-        faketime "1970-01-01 00:00:00" mkfs.vfat -i ${config.sdImage.bootPartitionID} -n NIXOS_BOOT bootpart.img
+        truncate -s $((SECTORS * 512)) firmware_part.img
+        faketime "1970-01-01 00:00:00" mkfs.vfat -i ${config.sdImage.firmwarePartitionID} -n FIRMWARE firmware_part.img
 
-        # Populate the files intended for /boot
-        mkdir boot
-        ${config.sdImage.populateBootCommands}
+        # Populate the files intended for /boot/firmware
+        mkdir firmware
+        ${config.sdImage.populateFirmwareCommands}
 
-        # Copy the populated /boot into the SD image
-        (cd boot; mcopy -psvm -i ../bootpart.img ./* ::)
+        # Copy the populated /boot/firmware into the SD image
+        (cd firmware; mcopy -psvm -i ../firmware_part.img ./* ::)
         # Verify the FAT partition before copying it.
-        fsck.vfat -vn bootpart.img
-        dd conv=notrunc if=bootpart.img of=$img seek=$START count=$SECTORS
+        fsck.vfat -vn firmware_part.img
+        dd conv=notrunc if=firmware_part.img of=$img seek=$START count=$SECTORS
       '';
     }) {};