powerpc/8xx: Save r3 all the time in DTLB miss handler
authorChristophe Leroy <christophe.leroy@c-s.fr>
Tue, 9 Feb 2016 16:07:48 +0000 (17:07 +0100)
committerScott Wood <oss@buserror.net>
Fri, 11 Mar 2016 23:18:01 +0000 (17:18 -0600)
commit913a6b3d10d85a032eff2f31254c35e0976f5e32
treedb23606c7e07020add9bfd29f9b65dbdc761481c
parent3b5eb41b8ce0a8be1e0da0f3f0f91cc29f4fcb16
powerpc/8xx: Save r3 all the time in DTLB miss handler

We are spending between 40 and 160 cycles with a mean of 65 cycles in
the DTLB handling routine (measured with mftbl) so make it more
simple althought it adds one instruction.
With this modification, we get three registers available at all time,
which will help with following patch.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
arch/powerpc/kernel/head_8xx.S