[meta-ti] U-Boot 2017.01 uEnv.txt Resolution (Raw Mode)

[Robert Nelson]

On Fri, Jul 14, 2017 at 7:58 PM, Robert Nelson <robertcnelson at gmail.com> wrote:
> On Fri, Jul 14, 2017 at 6:18 PM, Kenny Koller
> <kenny at understoryweather.com> wrote:
>> I'm attempting to use the raw mode to boot a Beaglebone Black. I've loaded
>> MLO and U-Boot at 128 kB and 384 kB and it successfully loads and runs
>> U-Boot but fails to find and load a uEnv.txt because I'm unsure where to
>> place it. I tried /boot on an EXT4 root filesystem.
>>
>> I suppose raw mode is a PPL thing and there is no way for U-Boot to know
>> about this and it can only support one way of loading the environment (which
>> is to fatload from partition 1)?
>>
>> I tried to resolve this in the Beaglebone community but I'm told that
>> documentation won't be applicable unless I apply a patch. But I'd prefer to
>> use the stock Yocto build.
>
> Correct, my doc's utilize my patch..
>
> it's weird how you have 10 posts on the community, but only actually
> responded to '1' after someone has replied to most of them.. it's like
> you just want us to do everything for you.. say it aint so...
>
>> I hope you don't mind fielding this question. It's not clear to me how much
>> of U-Boot is mainline from DENX, how much is from Robert Nelso, and how much
>> is from meta-ti.
>
> i do see an issue with pure-mainline u-boot:
>
> 61 #define BOOTENV_DEV_LEGACY_MMC(devtypeu, devtypel, instance) \
> 62         "bootcmd_" #devtypel #instance "=" \
> 63         "setenv mmcdev " #instance"; "\
> 64         "setenv bootpart " #instance":2 ; "\
> 65         "run mmcboot\0"
>
> Change line 64, 2 -> 1
>
> http://git.denx.de/?p=u-boot.git;a=blob;f=include/configs/am335x_evm.h;h=b97f525994d8002a1a44b17636fafc32eccbd20b;hb=HEAD#l64
>
> as it's scanning the second partition by default..
>
> so it should find /uEnv.txt after that fix for a single partition..

and here too:

http://git.denx.de/?p=u-boot.git;a=blob;f=include/configs/am335x_evm.h;h=b97f525994d8002a1a44b17636fafc32eccbd20b;hb=HEAD#l105

lots of hard-coding for the 2nd partition..

Regards,

-- 
Robert Nelson
https://rcn-ee.com/