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Date: Thu, 27 Aug 2009 10:59:07 -0500
From: Scott Wood <scottwood@freescale.com>
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To: "wilbur.chan" <wilbur512@gmail.com>
Subject: Re: Can't write value into memory ?(E500 V2)
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wilbur.chan wrote:
> I am using a SMP E500 v2, and I want CPU0 to write some value to a 
> physical address, and  wait for CPU1 to read from it.

Is this under Linux (it is a Linux mailing list...)?  If so, there are 
better ways of communicating that don't involve clobbering random memory 
and overlapping userspace TLB mappings.

> However, it seemed failed to communicate between CPUs by DRAM..  CPU1 
> can not read
>  
> the correct value from the address where CPU1 wrote to.

Do both cores have a mapping with the M bit (memory coherence required) set?

-Scott