Subject: Re: boot NetBSD using u-boot
To: Allen Briggs <>
From: Sam Pham <>
List: port-powerpc
Date: 10/06/2005 12:41:00
Thank you for your inputs.  They're all very helpful
for me because I'm currently porting NetBSD on the
mpc8540eval board, which already has u-boot running,
and I will have to learn more about u-boot once our
custom board is available.  Hopefully at that time,
porting NetBSD on this custom board will be smoother,
and I can concentrate more on u-boot.

For PCI memory mapping comment, my understanding is
that it depends on the intent of what we use the
bootloader for.  In our case, we plan to develop the
BIST for the PCI devices in u-boot, so we need to map
their memory to be able to read/write to them.  But if
the bootloader just needs to have basic
functionalities, OS like linux kernel 2.6 will map the
PCI memory dynamically to support plug & play devices.
 I still need to find out if it's the same for NetBSD
though :).



--- Allen Briggs <> wrote:

> On Thu, Oct 06, 2005 at 07:02:31AM -0400, Fraser,
> Doug wrote:
> > The other thing to know, is that your boot code is
> reponsible
> > for setting up the controller. Look at the port
> that is closest
> > to what you are using (CPU, and bridge if it is
> not an integrated chip).
> If I understand correctly, Sam is using a
> development board with
> U-Boot, which will take care of this early
> initialization and his
> concern is getting from U-Boot to a running kernel.
> As I'm sure you know, he specifically does NOT want
> to deal with
> SDRAM configuration once he's running in SDRAM.  :-)
> But if this is part of a larger project to get
> NetBSD running on
> a custom board, then it's certainly good information
> to file for
> later when he's updating the boot code for the new
> board.
> -allen
> -- 
>                   Use NetBSD! 

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