[U-Boot] [PATCH 7/7] sunxi: Add environment settings to make extlinux.conf booting work

[Stephen Warren]

On 08/01/2014 02:05 PM, Dennis Gilmore wrote:
> On Fri, 01 Aug 2014 12:57:31 -0600
> Stephen Warren <swarren at wwwdotorg.org> wrote:
>
>> On 08/01/2014 01:46 AM, Hans de Goede wrote:
>>> Automatic booting using an extlinux.conf file requires various
>>> environment variables to be set.
>>
>> Acked-by: Stephen Warren <swarren at nvidia.com>
>>
>> I'd personally be tempted to set fdt_high=0xffffffff,
>> initrd_high=0xffffffff to stop U-Boot copying the DT/initrd from the
>> load location to some other location under 256M, but that's just an
>> optimization and entirely optional.
>
> There has been quite a few times where using 0xffffff has caused
> issues.

What kind of issues?

At least for Tegra, I've carefully chosen the values for the various 
load addresses so that there won't be issues. (Without that I can easily 
see the potential for issues.) I've seen far more repeated problems when 
U-Boot moves the DT/initrd around than than when it didn't (none in that 
case). Besides, it's completely redundant and unnecessary work if the 
blobs are already loaded at sane addresses, which they are on Tegra at 
least.