powerpc/8xx: don't use r12/SPRN_SPRG_SCRATCH2 in TLB Miss handlers
authorChristophe Leroy <christophe.leroy@c-s.fr>
Thu, 29 Nov 2018 14:07:24 +0000 (14:07 +0000)
committerMichael Ellerman <mpe@ellerman.id.au>
Tue, 4 Dec 2018 08:45:01 +0000 (19:45 +1100)
commit74fabcadfd434065d0088f424905599298c5b2d2
tree68ac66bd2e40d617d22755426574ccb9b087254b
parent55c8fc3f4930286580af98711a481f35fa564e42
powerpc/8xx: don't use r12/SPRN_SPRG_SCRATCH2 in TLB Miss handlers

This patch reworks the TLB Miss handler in order to not use r12
register, hence avoiding having to save it into SPRN_SPRG_SCRATCH2.

In the DAR Fixup code we can now use SPRN_M_TW, freeing
SPRN_SPRG_SCRATCH2.

Then SPRN_SPRG_SCRATCH2 may be used for something else in the future.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch/powerpc/kernel/head_8xx.S