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<TITLE>RE: dcr stuff.</TITLE>
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<P><FONT SIZE=2>-----Original Message-----<BR>
From: Josh Boyer [<A HREF="mailto:jwboyer@linux.vnet.ibm.com">mailto:jwboyer@linux.vnet.ibm.com</A>]<BR>
Sent: Fri 3/21/2008 6:17 PM<BR>
To: Stephen Neuendorffer<BR>
Cc: linuxppc-dev@ozlabs.org; git-dev<BR>
Subject: Re: dcr stuff.<BR>
<BR>
On Fri, 21 Mar 2008 12:05:40 -0700<BR>
"Stephen Neuendorffer" <stephen.neuendorffer@xilinx.com> wrote:<BR>
<BR>
> > Is there a plan here? (In particular, in FPGA designs, its possible to<BR>
> > have crazy things like multiple independent dcr busses, some using<BR>
> > native access, some using mmio. Or even if there is one bus, many of<BR>
> > the existing non-linux drivers we have assume native or mmio access.<BR>
> > I'd like to clean this up, obviously.. :)<BR>
<BR>
> Clean it up how? I'd hate to add bloat to boards with native DCR<BR>
> access just because a few require oddities.<BR>
><BR>
> If it ain't broke, don't fix it.<BR>
><BR>
> josh<BR>
<BR>
Certainly, if it ain't broke don't fix it. What I'm really trying to do is figure out how to clean up alot of non-mainline drivers.<BR>
At the moment, several cores use DCR, but the drivers for those cores have internal code for DCR, their own ifdefs, etc. This *is* broken.<BR>
I'm looking at the available documentation to figure out the best way of approaching the problem.<BR>
<BR>
It might be nice if there was an extra layer of indirection which was only enabled if DCR_NATIVE and DCR_MMIO, and which was no cost otherwise,<BR>
but the bigger problem I see in the short term is that we'll likely have to support ARCH ppc for at least some time into the future, and it would be<BR>
nice if we used the same driver code to do it: it doesn't seem obvious how to achieve this.<BR>
<BR>
Steve<BR>
<BR>
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