[RFC PATCH v2 02/10] powerpc/32: Add EXCEPTION_PROLOG_0 in head_32.h

[Christophe Leroy]

This patch creates a macro for the very first part of
exception prolog, this will help when implementing
CONFIG_VMAP_STACK

Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr>
---
 arch/powerpc/kernel/head_32.S  | 4 +---
 arch/powerpc/kernel/head_32.h  | 9 ++++++---
 arch/powerpc/kernel/head_8xx.S | 9 ++-------
 3 files changed, 9 insertions(+), 13 deletions(-)

diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 9e6f01abb31e..53a9dab024c7 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -264,9 +264,7 @@ __secondary_hold_acknowledge:
  */
        . = 0x200
        DO_KVM  0x200
-       mtspr   SPRN_SPRG_SCRATCH0,r10
-       mtspr   SPRN_SPRG_SCRATCH1,r11
-       mfcr    r10
+       EXCEPTION_PROLOG_0
 #ifdef CONFIG_PPC_CHRP
        mfspr   r11, SPRN_SPRG_THREAD
        lwz     r11, RTAS_SP(r11)
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index b2ca8c9ffd8b..8e345f8d4b0e 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -10,13 +10,16 @@
  * We assume sprg3 has the physical address of the current
  * task's thread_struct.
  */
-
 .macro EXCEPTION_PROLOG
+       EXCEPTION_PROLOG_0
+       EXCEPTION_PROLOG_1
+       EXCEPTION_PROLOG_2
+.endm
+
+.macro EXCEPTION_PROLOG_0
        mtspr   SPRN_SPRG_SCRATCH0,r10
        mtspr   SPRN_SPRG_SCRATCH1,r11
        mfcr    r10
-       EXCEPTION_PROLOG_1
-       EXCEPTION_PROLOG_2
 .endm
 
 .macro EXCEPTION_PROLOG_1
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 5ab9178c2347..16d68c8575ca 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -493,10 +493,7 @@ InstructionTLBError:
  */
        . = 0x1400
 DataTLBError:
-       mtspr   SPRN_SPRG_SCRATCH0, r10
-       mtspr   SPRN_SPRG_SCRATCH1, r11
-       mfcr    r10
-
+       EXCEPTION_PROLOG_0
        mfspr   r11, SPRN_DAR
        cmpwi   cr0, r11, RPN_PATTERN
        beq-    FixupDAR        /* must be a buggy dcbX, icbi insn. */
@@ -529,9 +526,7 @@ DARFixed:/* Return from dcbx instruction bug workaround */
  */
        . = 0x1c00
 DataBreakpoint:
-       mtspr   SPRN_SPRG_SCRATCH0, r10
-       mtspr   SPRN_SPRG_SCRATCH1, r11
-       mfcr    r10
+       EXCEPTION_PROLOG_0
        mfspr   r11, SPRN_SRR0
        cmplwi  cr0, r11, (.Ldtlbie - PAGE_OFFSET)@l
        cmplwi  cr7, r11, (.Litlbie - PAGE_OFFSET)@l
-- 
2.13.3