Subject: Re: MPC82xx -- DPRAM1

From: Wolfgang Denk <[email-masked]>
Date: Thu, 18 Nov 2004 18:38:57 +0100

In message <[email-masked]> you wrote:
> 
> I do not understand all the intricacies of what happens regarding hardware 
> configuration during the eraly stages of booting linux, but I conclude 
> that when making a uImage one have to modify u-boot and the kernel if one 
> want to relocate the usage of dpram1 by the cpm uart driver. This might 
> have been obvious to most of you, but I was lost on this issue.

There is no need to modify U-Boot nor  the  kernel.  Each  driver  is
supposed to perform all required initialization steps itself. It must
not  make  any assumptions about it's previous state except that it's
"harmless", i. e. interrupts are disabled etc.  when  the  driver  is
starting.

> A mystery is why Dan Malek said it was a "very bad idea" to relocate the 
> smc buffer descriptors to anohter part of dpram1.
> Maybe I will understand that one day too.

Read the code.

Best regards,

Wolfgang Denk

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