[OE-core] [PATCH 0/1] Add new FSTYPE: multiubi

[Pushpal Sidhu]

I am submitting a patch that will add a new filesystem type called 'multiubi'. Without repeating my commit message verbatim, I want the ability to create multiple ubi's that cater to different flash sizes.

This is ideal for some boards I've encountered that can have anywhere from nMB to nGB of flash storage space (but be the same 'machine'), in which case tweaking the machine.conf file to change ubi parameters doesn't make sense. In order to not rewrite code, I have added a function to generically create ubi files where FSTYPE's 'ubi' and 'multiubi' can reuse the code. This should not break any current configs that build with a FSTYPE of 'ubi'.

An example conf file could include the following:
> # Override FS Type Creation
> IMAGE_FSTYPES = "tar.bz2 multiubi"
>
> # Build the following sizes
> MULTIUBI_BUILD ?= "normal large"
>
> # 256MB ('normal' flash layout)
> export MKUBIFS_ARGS_normal = "-F -m 2048 -e 124KiB -c 1912 -x zlib"
> export UBINIZE_ARGS_normal = "-m 2048 -p 128KiB -s 2048"
>
> # 2GB ('large' flash layout)
> export MKUBIFS_ARGS_large = "-F -m 4096 -e 248KiB -c 8124 -x zlib"
> export UBINIZE_ARGS_large = "-m 4096 -p 256KiB -s 4096"

Due to the way OE deals with created images, the shared function 'multiubi_mkfs' has to create its own symbolic links in the DEPLOY_DIR_IMAGE directory and clean up it's own config files. If there are suggestions on how I can overcome this, please let me know.

I appreciate any questions/comments.

Thanks,
- Pushpal