powerpc/85xx: Save scratch registers to thread info instead of using SPRGs.
We expect this is actually faster, and we end up needing more space than we
can get from the SPRGs in some instances. This is also useful when running
as a guest OS - SPRGs4-7 do not have guest versions.
8 slots are allocated in thread_info for this even though we only actually
use 4 of them - this allows space for future code to have more scratch
space (and we know we'll need it for things like hugetlb).
Signed-off-by: Ashish Kalra <Ashish.Kalra@freescale.com>
Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index c5cae0d..213d1d7 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -872,8 +872,8 @@
#define SPRN_SPRG_WSCRATCH2 SPRN_SPRG4W
#define SPRN_SPRG_RSCRATCH3 SPRN_SPRG5R
#define SPRN_SPRG_WSCRATCH3 SPRN_SPRG5W
-#define SPRN_SPRG_RSCRATCH_MC SPRN_SPRG6R
-#define SPRN_SPRG_WSCRATCH_MC SPRN_SPRG6W
+#define SPRN_SPRG_RSCRATCH_MC SPRN_SPRG1
+#define SPRN_SPRG_WSCRATCH_MC SPRN_SPRG1
#define SPRN_SPRG_RSCRATCH4 SPRN_SPRG7R
#define SPRN_SPRG_WSCRATCH4 SPRN_SPRG7W
#ifdef CONFIG_E200