lbailly/liminix
1
0
Fork 0
forked from DGNum/liminix
Code Pull requests 2 Activity Actions

modules/outputs/zyxel-nwa-fit: init

Browse source 
Zyxel "firmware" format is just… a FIT with some metadata on the models.

This FIT is like this:

--------------------------
    uImage FIT header
--------------------------
    Linux kernel
--------------------------
    FDT DTB
--------------------------
    Padding so that
    this makes
    8192kb [1]
--------------------------
    UBI volume
    as a root filesystem
--------------------------

We just reproduce this in a very brutal and naive way.
In the future, this seems worth to generalize and modularize this idea
so that zyxel-nwa-fit is just an instance of a more general output.

[1]: https://git.openwrt.org/?p=openwrt/openwrt.git;a=blob;f=target/linux/ramips/image/mt7621.mk;h=ab1b829ba0086cb9fc9ca8cbbf3cbc14735034d6;hb=refs/heads/main#l3097

Signed-off-by: Raito Bezarius <masterancpp@gmail.com>
This commit is contained in:
Raito Bezarius 2024-02-17 02:21:50 +01:00
parent e9ab8d7183
commit 63007859c2
1 changed files with 71 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

71
modules/outputs/zyxel-nwa-fit.nix Normal file
View file

@ -0,0 +1,71 @@
{
config
, pkgs
, lib
, ...
}:
let
inherit (lib) mkIf mkEnableOption mkOption types concatStringsSep;
models = "6b e1 6f e1 ff ff ff ff ff ff";
in {
options.system.outputs = {
zyxel-nwa-fit = mkOption {
type = types.package;
description = ''
zyxel-nwa-fit
*************
This output provides a FIT image for Zyxel NWA series
containing a kernel image and an UBIFS rootfs.
It can usually be used as a factory image to install Liminix
on a system with pre-existing firmware and OS.
'';
};
};
imports = [
./ubivolume.nix
];
config = mkIf (config.rootfsType == "ubifs") {
system.outputs.zyxel-nwa-fit =
let
o = config.system.outputs;
# 8129kb padding.
paddedKernel = pkgs.runCommand "padded-kernel" {} ''
cp --no-preserve=mode ${o.uimage} $out
dd if=/dev/zero of=$out bs=1 count=1 seek=8388607
'';
firmwareImage = pkgs.runCommand "firmware-image" {} ''
cat ${paddedKernel} ${o.rootfs} > $out
'';
dts = pkgs.writeText "image.its" ''
/dts-v1/;
/ {
description = "Zyxel FIT (Flattened Image Tree)";
compat-models = [${models}];
#address-cells = <1>;
images {
firmware {
data = /incbin/("${firmwareImage}");
type = "firmware";
compression = "none";
hash@1 {
algo = "sha1";
};
};
};
};
'';
in
pkgs.runCommand "zyxel-nwa-fit" {
nativeBuildInputs = [ pkgs.pkgsBuildBuild.ubootTools pkgs.pkgsBuildBuild.dtc ];
} ''
mkimage -f ${dts} $out
'';
};
}