[U-Boot] [PATCH 6/6] cmd: Add "boot_android" command.

[Stanislas BERTRAND]

Hi Sam,


> Can I ask you some questions about this code?
>  1. Do I understand correctly that this is just some old patch hanging
> in mailing list [1]?

Yes, it is from an old post to the mailing list.

>  2. What is the motivation of adding this command? We already have
> Android boot image support in bootm command, which we successfully use
> in TI just by loading needed images to RAM and then passing them to
> bootm, like this: [2].

I am working to get a Android A/B System implementation on my board.
I was looking to reuse existing implementation. Aiming to stay close to the mainline.

The command boot_android performs the different loading and checks required before calling bootm.

Like Alex mentioned [4], those patch series are not recent but it was good starting point of implementation.
I had to perform some customization to have a functional boot flow adapted to my system ( Android 7.1.1, Linux 4.4.45, U-Boot 2017.0 ).

I am not pushing to have this particular implementation mainline.
However having a mainline implementation for Android A/B system,
would be nice. I was giving feedback from my particular system usage.

>  3. Can you provide more information about how this code works? And
> probably show some relevant link from Android documentation where it
> says about boot flow implemented here?

>  [1] https://lists.denx.de/pipermail/u-boot/2017-April/285847.html
> [2] http://git.denx.de/?p=u-boot.git;a=blob;f=include/environment/ti/boot.h;h=24b7783f88947db07480d814c798e51197c07ce2;hb=HEAD#l38
<https://lists.denx.de/listinfo/u-boot>
More information was posted by Alex in his original patch series [3].

Alex, I did add loading of the FDT in the boot_android command. How did you load your at 'fdt_addr' ?

<https://lists.denx.de/pipermail/u-boot/2018-April/325674.html>

Thanks,

[3] https://lists.denx.de/pipermail/u-boot/2017-April/285841.html
[4] https://lists.denx.de/pipermail/u-boot/2018-April/325674.html