From: Dave Liu <r63238@freescale.com>
Date: Fri, 25 Apr 2008 18:28:04 +0800
Subject: [U-Boot-Users] [PATCH][RFC] lib_ppc: make the flush_cache
	stronger
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> > Current flush_cache code does
> >
> > 1. clean the dcache with dcbst, but not invalidate dcache
> > 2. invalidate icache
> >
> > This patch use the dcbf instead of dcbst to have stronger
> > semantic, clean the dcache and invalidate dcache.
> 
> On which processors did you test the changes? I have some unclear
> memories of dcbf having problems on for example MPC8xx ?

on 83xx parts.
I remember the 601 processor not support the dcbf.

> > We have two options:
> >
> > 1. Separate functions for them like linux kernel.
> >    A. clean dcache (dcbst) for DMA_TO_DEVICE
> >    B. invalidate dcache (dcbi) for DMA_FROM_DEVICE
> >    C. flush dcache (dcbf) for DMA_BIDIRECTIONAL.
> > 2. Make current flush_cache stronger semanctic.
> >    use the dcbf instead of dcbst.
> >
> > Which one is better? or you have better option?
> > Please suggest.
> 
> We discussed this a bit on IRC; Kumar suggested to go for 1., and I
> agree.

Where is the IRC? Could you point it to me?

Thanks,
Dave