Enable of Data Cache on mpc8240 and mpc8245
strauman at slac.stanford.edu
Wed Feb 22 22:54:11 UTC 2006
Jennifer Averett wrote:
>I don't know if anyone has already resolved this,
I had. (my message from 2005/11/18 attached).
I committed everything *but* the actual L1_caches_enables() call
(I got delayed and now I don't have the loaner 2100 board anymore).
However, I am sure I tested it and it worked. But since I cannot test,
I was reluctant to commit this.
> but I was able to enable
>data cache on an mpc8245 processor. I had to move the L1_caches_enables
>call to the bottom of the pretasking hook.
why would you have to do that? For me, it worked the 'normal' way:
start.S: cache off, MMU off
setup bat to map memory
(should set up basic/empty page table but that is currently
setup MMU/bat mappings for I/O *prior* to doing *any* I/O
enable L1 cache
Two states that must be avoided:
MMU off, cache on [all operations would be write-back cached,
which is bad]
MMU on, insufficient mappings [ I/O fails w/o a way to print to console]
-------------- next part --------------
An embedded message was scrubbed...
From: Till Straumann <strauman at slac.stanford.edu>
Subject: Re: cache on mvme2100
Date: Fri, 18 Nov 2005 14:17:23 -0800
More information about the users