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Re: PATCH RFA: Don't set GFXOPT for 8540 or 8548
Daniel Jacobowitz <drow@false.org> writes:
> On Mon, Apr 23, 2007 at 05:00:14PM -0700, Ian Lance Taylor wrote:
> > It seems to me that the PowerPC 8540 and 8548 do not support the
> > PowerPC GFX instructions. They do support isel, but not instructions
> > like stfiwx. This patch adjusts the settings accordingly.
> >
> > Tested by building gcc and confirming that it no longer generates the
> > stfiwx instructions. I don't have access to an 8540 for proper
> > testing.
>
> What's your reference for this? I checked the e500 core manual, which
> agrees, but I also ran a program using stfiwx on an 8548 and no
> exception was raised. I'm not sure if the Linux kernel is getting in
> the way and emulating it, though.
I checked the e500 manual, and I have a bug report from somebody using
an 8541 running an embedded RTOS which is getting an exception for
stfiwx. I don't know about the 8548 specifically.
Ian