Hi Eugeniu,
On Mon, 20 May 2019 at 01:23, Eugeniu Rosca erosca@de.adit-jv.com wrote:
Hi Simon cc: Sam, Igor, feel free to correct/augment anything of below
On Sat, May 18, 2019 at 10:33:02AM -0600, Simon Glass wrote:
Hi Eugeniu,
On Fri, 17 May 2019 at 08:46, Eugeniu Rosca erosca@de.adit-jv.com wrote:
'Bootloader Control Block' (BCB) is a well established term/acronym in the Android namespace which refers to a location in a dedicated raw (i.e. FS-unaware) flash (e.g. eMMC) partition, usually called "misc", which is used as media for exchanging messages between Android userspace (particularly recovery [1]) and an Android-capable bootloader.
[..]
Where is this documented? Perhaps it should go in README.avb2?
README.avb2 is solely about the "verified/secure" booting of Android, while the 'bcb' command proposed in this patch can be useful both in verified boot scenarios (e.g. full-featured U-Boot builds), as well as in non-avb ones (e.g. development, PoC, demos, custom configurations). Thus, I think that README.avb2 is not the best place for 'bcb'.
More generally, as somebody who uses git as an extension of himself, I am quite happy with commit-only documentation. OTOH, for those who receive U-Boot in tarballs or expect source-level docs/tutorials, I agree that having the 'bcb' described in a README might be helpful.
I can identify two Android-dedicated README files, but none of them seems to be suitable for the new command:
- doc/README.android-fastboot
- doc/README.avb2
Igor, Sam, what's your view on the above? Would you suggest creating a doc/README.android-bcb or there is a more elegant solution to it?
How about a new README.android which links to the other two and adds your new info?
Should it default to enabled if avb is used?
I think at this specific moment in time, 'bcb' is orthogonal (meaning it is neither a direct, nor a reverse dependency) to any other Android feature in U-Boot. This could be re-assessed, if platform maintainers start to rely on 'bcb' in their U-Boot environments on regular basis.
OK. Also is there a sandbox driver for this? We should have a test.
Regards, Simon