[RFC][PATCH 0/2] Make sparcv8 work again on cas enabled hardware

[David Miller]

From: Torvald Riegel <triegel@redhat.com>
Date: Thu, 03 Nov 2016 16:39:21 +0100

> Is there any difference between the additional CAS on a v8 and the CAS
> on a v9?  If there should be none (eg, same instruciton encoding etc.),
> we wouldn't need a runtime check for this, would we?

A quick look at binutils shows that the encoding appears to be the same.

> That depends on whether we want to support sparc HW that does have a
> CAS.  It's still not clear to me whether this is a goal, and if it's a
> goal, whether it's a goal for today or for some time in the future.

I think there is value in supporting pure-v8, however painful it may
be.

I personally don't like to see when we drop support for old systems on
the floor just because it's too inconvenient or cumbersome to keep
them working properly.