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From: dirk.behme@de•bosch.com (Dirk Behme)
To: linux-arm-kernel@lists•infradead.org
Subject: [Query] Does u-boot processes dtb file
Date: Fri, 14 Sep 2012 09:08:26 +0200	[thread overview]
Message-ID: <5052D7EA.30902@de.bosch.com> (raw)
In-Reply-To: <CAKohpomkgk_hNAwqseAvc_cyLH+Vtr63r_hJGxsKueZhKno8_A@mail.gmail.com>

On 14.09.2012 08:58, Viresh Kumar wrote:
> Hi Arnd,
> 
> 
> Sorry for the stupid question, but somebody asked this to me and i wasn't sure
> about it.
> 
> We boot with dtb from u-boot using following command:
> bootm <uImage addr> <initrd addr> <dtb addr>
> 
> Does u-boot do anything special or simply passes address of dtb in r2 to kernel?
> 
> i.e. if i do bootm <uImage addr> and stop my kernel early using a debugger,
> update r2 with dtb address, will it work the same way?
> 
> OR
> 
> Does any bootloader needs some special code for handling dtb's?

Working with U-Boot, to my understanding U-Boot modifies ('patches') the 
dtb read from the boot device before passing it to the kernel. It e.g. 
adds the kernel command line and the memory size you specify in U-Boot 
to the dtb.

Best regards

Dirk

  reply	other threads:[~2012-09-14  7:08 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-09-14  6:58 [Query] Does u-boot processes dtb file Viresh Kumar
2012-09-14  7:08 ` Dirk Behme [this message]
2012-09-14  7:16   ` Viresh Kumar
2012-09-14  7:35     ` Dirk Behme
2012-09-14  9:16       ` Stefan Roese

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