Subject: Re: [PATCH] powerpc: Merge align.c

From: Benjamin Herrenschmidt <[email-masked]>
Date: Wed, 16 Nov 2005 16:00:35 +1100

On Tue, 2005-11-15 at 23:26 -0500, Dan Malek wrote:
> On Nov 15, 2005, at 9:34 PM, Benjamin Herrenschmidt wrote:
> 
> > What about lwz/stw cropssing page boundaries ? Is this handled in HW ?
> 
> Yep.  All of these hardware alignment support features on
> the Freescale processors are the reasons they are used
> so extensively in data communication processing (where
> unaligned data can sometimes occur).  All of the load/store
> alignment issues are handled in the cache subsystem, so
> to the external world all you really see are cache line
> operations.  In the event of uncached data operations, you
> get the performance penalty of two bus accesses, where
> some of the data is discarded.

Oh well, I suppose I'll have to dig out paulus' 601 based mac :)

Becky, can you send me a copy of your testcase ?

Ben.