liminix/modules/outputs/flashimage.nix
2023-11-12 18:37:33 +00:00

117 lines
3.8 KiB
Nix

{
config
, pkgs
, lib
, ...
}:
let
inherit (lib) mkOption types concatStringsSep;
inherit (config.boot) tftp;
in {
options.system.outputs = {
firmware = mkOption {
type = types.package;
internal = true; # component of flashimage
description = ''
Binary image (combining kernel, FDT, rootfs, initramfs
if needed, etc) for the target device.
'';
};
flash-scr = mkOption {
type = types.package;
internal = true; # component of flashimage
description = ''
Copy-pastable U-Boot commands to TFTP download the
image and write it to flash
'';
};
flashimage = mkOption {
type = types.package;
description = ''
flashimage
**********
This creates an image called :file:`firmware.bin` suitable for
squashfs or jffs2 systems. It can be flashed from U-Boot (if
you have a serial console connection), or on some devices from
the vendor firmware, or from a Liminix kexecboot system.
If you are flashing from U-Boot, the file
:file:`flash.scr` is a sequence of commands
which you can paste at the U-Boot prompt to
to transfer the firmware file from a TFTP server and
write it to flash. **Please read the script before
running it: flash operations carry the potential to
brick your device**
.. NOTE::
TTL serial connections typically have no form of flow
control and so don't always like having massive chunks of
text pasted into them - and U-Boot may drop characters
while it's busy. So don't necessarily expect to copy-paste
the whole of :file:`flash.scr` into a terminal emulator and
have it work just like that. You may need to paste each
line one at a time, or even retype it.
'';
};
};
config = {
kernel = {
config = {
MTD_SPLIT_UIMAGE_FW = "y";
} // lib.optionalAttrs (pkgs.stdenv.isMips) {
# https://stackoverflow.com/questions/26466470/can-the-logical-erase-block-size-of-an-mtd-device-be-increased
MTD_SPI_NOR_USE_4K_SECTORS = "n";
};
};
programs.busybox.applets = [
"flashcp"
];
system.outputs = {
firmware =
let
o = config.system.outputs;
bs = config.hardware.flash.eraseBlockSize;
in pkgs.runCommand "firmware" {} ''
dd if=${o.uimage} of=$out bs=${bs} conv=sync
dd if=${o.rootfs} of=$out bs=${bs} conv=sync,nocreat,notrunc oflag=append
'';
flashimage =
let o = config.system.outputs; in
# could use trivial-builders.linkFarmFromDrvs here?
pkgs.runCommand "flashimage" {} ''
mkdir $out
cd $out
ln -s ${o.firmware} firmware.bin
ln -s ${o.rootfs} rootfs
ln -s ${o.kernel} vmlinux
ln -s ${o.manifest} manifest
ln -s ${o.kernel.headers} build
ln -s ${o.uimage} uimage
ln -s ${o.dtb} dtb
ln -s ${o.flash-scr} flash.scr
'';
flash-scr =
let
inherit (pkgs.lib.trivial) toHexString;
inherit (config.hardware) flash;
in
pkgs.buildPackages.runCommand "" {} ''
imageSize=$(stat -L -c %s ${config.system.outputs.firmware})
cat > $out << EOF
setenv serverip ${tftp.serverip}
setenv ipaddr ${tftp.ipaddr}
tftp 0x${toHexString tftp.loadAddress} result/firmware.bin
erase 0x$(printf %x ${flash.address}) +${flash.size}
cp.b 0x${toHexString tftp.loadAddress} 0x$(printf %x ${flash.address}) \''${filesize}
echo command line was ${builtins.toJSON (concatStringsSep " " config.boot.commandLine)}
EOF
'';
};
};
}