I have created my custom initramfs that is working with raspbian, but when I try to boot to it with openwrt, it is ignored.
To use initramfs with raspbian you only need to edit the config.txt:
initramfs initramfs.cpio.gz followkernel
The same config does nothing on openwrt. Maybe someone has encountered the same problem?
OpenWrt doesn't use an initramfs (apart from the initramfs images, but that's a totally different thing).
Yes. What I’m trying to do is decrypt the emmc in the initramfs. Is the initramfs support removed from openwrt kernel?
From the kernel, no.
But userspace- and build side, there is no initramfs support.
Maybe you know the best way I could decrypt it then? Would preinit scripts be closest to what I want to do?
Start by moving sdcard somewhere else. Openwrt is not a forensics tool (outside maybe imaging itself)
CONFIG_TARGET_INITRAMFS_FORCE=y
CONFIG_TARGET_ROOTFS_INITRAMFS=y
CONFIG_USES_SEPARATE_INITRAMFS=n
CONFIG_TARGET_ROOTFS_INITRAMFS_SEPARATE=n
The problem was with how initramfs is passed via the config.txt. I used initramfs <name> <place> and it didn’t work. When I tried with the old method: ramfsaddr and ramfsfile, it worked.
Additionally, I added these kernel parameters: CONFIG_BLK_DEV_INITRD and CONFIG_RD_GZIP for gzip support