On Mon, 17 Sep 2018 11:30:16 +0530 "Aneesh Kumar K.V" <aneesh.ku...@linux.ibm.com> wrote:
> Nicholas Piggin <npig...@gmail.com> writes: > > > The POWER5 < DD2.1 issue is that slbie needs to be issued more than > > once. It came in with this change: > > > > ChangeSet@1.1608, 2004-04-29 07:12:31-07:00, da...@gibson.dropbear.id.au > > [PATCH] POWER5 erratum workaround > > > > Early POWER5 revisions (<DD2.1) have a problem requiring slbie > > instructions to be repeated under some circumstances. The patch below > > adds a workaround (patch made by Anton Blanchard). > > Thanks for extracting this. Can we add this to the code? The comment? Sure. > Also I am not > sure what is repeated here? Is it that we just need one slb extra(hence > only applicable to offset == 1) or is it that we need to make sure there > is always one slb extra? The code does the former. Yeah it has always done the former, so my assumption is that you just need more than one slbie. I don't think we need to bother revisiting that assumption unless someone can pull up something definitive. What I did change is that slbia no longer has the additional slbie, but I think there are strong reasons not to need that. > Do you a have link for > that email patch? I tried looking through the archives around that date but could not find it. That came from a bitkeeper log. Thanks, Nick
