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Date: Wed, 21 May 2008 14:14:09 +1000
From: Paul Mackerras <paulus@samba.org>
To: Andrew Liu <shengping.liu@windriver.com>
Subject: Re: [PATCH] [POWERPC] Uniformly use memstart_addr variable as the
	start address of physical memory in powerpc branch
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Andrew Liu writes:

> You know we can't make sure in future the start address of all incoming 
> boards' RAM is 0, especially, in AMP system, different cpu uses the different RAM area, 
> definitely, the start address of some is not 0.

Any processor that uses ppc_mmu_32.c will have interrupt vectors in
the 0 - 0x3000 region of memory and hence *must* have RAM starting at
zero.  In other words, that file is only used for "classic" 32-bit
PowerPC processors, not for anything based on Book E or Power
architecture v2.04 or later.

Paul.