[U-Boot] [PATCH] arm: Tegra2: Add a useful default boot env

[Stephen Warren <swarren@wwwdotorg.org>]

On 04/23/2012 10:22 AM, Tom Warren wrote:
> Stephen,
> 
> On Fri, Apr 20, 2012 at 2:40 PM, Stephen Warren <swarren@wwwdotorg.org> wrote:
>> On 04/20/2012 01:50 PM, Tom Warren wrote:
>>> This set of boot cmds from Stephen Warren provides a simple
>>> default for booting a linux kernel and DT from mmc (eMMC or
>>> SD-Card, in that order). Tested on Seaboard w/an SD card.
>> ...
>>> diff --git a/include/configs/tegra2-common.h b/include/configs/tegra2-common.h
>> ...
>>>  #define CONFIG_EXTRA_ENV_SETTINGS \
>> ...
>>> +     "script=/boot.scr.uimg\0" \
>>
>> It might be best to make that just /boot.scr. The reason being that I
>> looked at the Ubuntu Precise images for OMAP, and they don't have
>> ".uimg" in the filename, even though they're uImage files. It's probably
>> best to be consistent with the Ubuntu images given the only other
>> precedent is what I do locally, which can easily be adjusted.
> 
> I'll change it to /boot.scr, but do we have any stats on other/more
> distros and what they use?

I don't believe any other distros are creating packages/images for Tegra
yet.

> As to using fat instead of ext2, this is just an example, and would be
> (should be) customized for each vendor/distro.
> I could also add a USB boot example.

Really, we should be defining the boot architecture for Tegra, and
distros following suite. So, I think we should just say:

* Partition 1 of the media is /boot.
* Partition 1 should be ext2 or compatible.
* boot.scr should exist there and be a uImage script file.

Distros certainly can't customize the U-Boot environment for themselves,
since there's no generally applicable way of doing so. That's exactly
why I pushed to load a boot.scr rather than having U-Boot load the
kernel directly (and define the command-line), to give distros the
ability to customize boot.scr; generating files in a filesystem is much
easier for distros.