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Message-ID: <1388400511.30225.11.camel@dagon.hellion.org.uk>
Subject: Re: [PATCH 0/7] arm-uboot: support for different RAM bases
From: Ian Campbell <ijc@hellion.org.uk>
To: Vladimir =?UTF-8?Q?=27=CF=86-coder/phcoder=27?= Serbinenko
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Date: Mon, 30 Dec 2013 10:48:31 +0000
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On Mon, 2013-12-30 at 02:55 +0100, Vladimir '=CF=86-coder/phcoder' Serbinen=
ko
wrote:
> Is there a way to make uboot to load GRUB at some appropriate address.

I don't think there is with the uImage format which grub uses today. It
contains a load address in the header which AFAIK is an absolute address
with no scope for "u-boot chooses" or "offset from start of RAM" or
anything like that.

In theory we could drop the uImage header and just us a plain Linux
zImage via u-boot's "bootz" command, which would then put things in the
hands of the u-boot boot script and environment, but that is not all
that widely available yet, whereas "bootm" is pretty much everywhere.

> We can do relocations in the startup code if needed.

The above notwithstanding I did wonder about this but it seems like
potentially complex code to write in the early asm portion of things.

I also vaguely played with -fpic/fpie but not with much success and I
don't know if that solution would be workable in practice.

Ian.