Re: Why is psr.ic off for ia64_pal_cache_flush?

Dean Roe
2006-01-05T15:25:41Z

On Mon, Dec 26, 2005 at 01:44:55PM +0800, Tian, Kevin wrote:
> I know that currently there's no such invocation to ia64_pal_cache_flush
> within ia64 linux kernel, but like to know why it's the only instance to
> call PAL_CALL_IC_OFF under virtual mode? Since there's no DTR setup for
> pal area, it can only work if DTC entry exists just before off psr.ic,
> or pal procedure for this type doesn't issue any data access. Or else
> nested dtlb miss may happen and it seems not to be handled by current
> linux code.
>
> Currently this stub is invoked by XEN (an open source VMM with code
> derived from linux) to sync I/D cache after management tool loads kernel
> image and initrd of another domain (guest OS). Though we may take place
> of it by fc.i, I'm still curious to know historical background for this
> design.
>
> Thanks in advance,
> Kevin

Did you get any responses to this? I played with ia64_pal_cache_flush
on an Altix (over a year ago) and couldn't get it to work without
converting it to use PAL_CALL. Are you having a similar problem when
you use it for XEN?

Dean

--
Dean Roe
Silicon Graphics, Inc.
roe@sgi.com