This module generates a /boot/extlinux/extlinux.conf bootloader
configuration file that is supported by e.g. U-Boot:
http://git.denx.de/?p=u-boot.git;a=blob;f=doc/README.distro;hb=refs/heads/master
With this, all ARM boards supported by U-Boot can be booted in a common
way (a single boot file generator, all boards booting via initrd like
x86) and with same boot menu functionality as GRUB has.
-- sample extlinux.conf file --
# Generated file, all changes will be lost on nixos-rebuild!
# Change this to e.g. nixos-42 to temporarily boot to an older configuration.
DEFAULT nixos-default
TIMEOUT 50
LABEL nixos-default
MENU LABEL NixOS - Default
LINUX ../nixos/n7vxfk60nb5h0mcbhkwwxhcz2q2nvxzv-linux-4.1.0-rc3-cpufreq-zImage
INITRD ../nixos/0ss2zs8sb6d1qn4gblxpwlxkfjsgs5f0-initrd-initrd
FDTDIR ../nixos/n7vxfk60nb5h0mcbhkwwxhcz2q2nvxzv-linux-4.1.0-rc3-cpufreq-dtbs
APPEND systemConfig=/nix/store/469qvr43ln8bfsnk5lzcz6m6jfcgdd4r-nixos-15.06.git.0b7a7a6M init=/nix/store/469qvr43ln8bfsnk5lzcz6m6jfcgdd4r-nixos-15.06.git.0b7a7a6M/init loglevel=8 console=ttyS0,115200n8 drm.debug=0xf
LABEL nixos-71
MENU LABEL NixOS - Configuration 71 (2015-05-17 21:32 - 15.06.git.0b7a7a6M)
LINUX ../nixos/n7vxfk60nb5h0mcbhkwwxhcz2q2nvxzv-linux-4.1.0-rc3-cpufreq-zImage
INITRD ../nixos/0ss2zs8sb6d1qn4gblxpwlxkfjsgs5f0-initrd-initrd
FDTDIR ../nixos/n7vxfk60nb5h0mcbhkwwxhcz2q2nvxzv-linux-4.1.0-rc3-cpufreq-dtbs
APPEND systemConfig=/nix/store/469qvr43ln8bfsnk5lzcz6m6jfcgdd4r-nixos-15.06.git.0b7a7a6M init=/nix/store/469qvr43ln8bfsnk5lzcz6m6jfcgdd4r-nixos-15.06.git.0b7a7a6M/init loglevel=8 console=ttyS0,115200n8 drm.debug=0xf
This reverts commit d170c98d13.
niksnut argues that we need smaller system closures, not bigger.
So users facing the trouble of getting gcc rebuilds after nix-collect-garbage
for any minimal nixos configuration change should use other means of
not losing the stdenv output.
One way is to keep one somewhere: nix-build -A stdenv -o stdenv '<nixpkgs>'.
Another may be to use nix.conf options like gc-keep-outputs, gc-keep-derivations
or env-keep-derivations.
This will help a lot on ARM, where nix-collect-garbage erases gcc; then, any
change to a small system config file requires rebuilding gcc again.
I don't know why it does not happen on x86. Maybe it just pulls the gcc from
hydra, if garbage is collected.
It boots, but some things still don't work:
1) Installation of DTBs
2) Boot of initrd
Booting still needs a proper config.txt in /boot, which could probably be
managed by NixOS.
