From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stefan Roese <sr@denx.de>
Date: Wed, 2 Jul 2008 11:38:04 +0200
Subject: [U-Boot-Users] CPU (405ep) clock upgrade..
In-Reply-To: <486B491C.4090503@fiberlogic.com>
References: <48687037.3000106@fiberlogic.com> <200806301427.43270.sr@denx.de>
	<486B491C.4090503@fiberlogic.com>
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On Wednesday 02 July 2008, Yi-Neng Lin wrote:
>  This arises another question. Assume that both configurations (CPU and
> SDRAM) are obtained from the EEPROM, how can C program/function be adopted
> to use these parameters before CPU/memory is initiated? C
> programs/functions need memory space to setup the stacks, which means
> CPU/memory initialization should be done (via assembly) before any C
> programs/functions can be used.

All this is already taken care of. U-Boot uses a small area for initial RAM. 
Sometimes in D-cache, sometimes in onboard SRAM (SoC). IIRC, the 405EP has 
OCM, so this could be used here. You just need to configure this correctly in 
your board config file. Again I suggest you take a look at the zeus board as 
an example.

Best regards,
Stefan

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