powerpc/8xx: Use SPRG2 instead of DAR for saving r3

We now have SPRG2 available as in it not used anymore for saving CR, so we don't
need to crash DAR anymore for saving r3 for CPU6 ERRATA handling.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <scottwood@freescale.com>

diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 150d03f..ba2dc53 100644 (file)
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -309,7 +309,7 @@ SystemCall:
 
 InstructionTLBMiss:
 #ifdef CONFIG_8xx_CPU6
-       mtspr   SPRN_DAR, r3
+       mtspr   SPRN_SPRG_SCRATCH2, r3
 #endif
        EXCEPTION_PROLOG_0
 
@@ -362,8 +362,7 @@ InstructionTLBMiss:
 
        /* Restore registers */
 #ifdef CONFIG_8xx_CPU6
-       mfspr   r3, SPRN_DAR
-       mtspr   SPRN_DAR, r11   /* Tag DAR */
+       mfspr   r3, SPRN_SPRG_SCRATCH2
 #endif
        EXCEPTION_EPILOG_0
        rfi
@@ -371,7 +370,7 @@ InstructionTLBMiss:
        . = 0x1200
 DataStoreTLBMiss:
 #ifdef CONFIG_8xx_CPU6
-       mtspr   SPRN_DAR, r3
+       mtspr   SPRN_SPRG_SCRATCH2, r3
 #endif
        EXCEPTION_PROLOG_0
        mfcr    r10
@@ -438,7 +437,7 @@ DataStoreTLBMiss:
 
        /* Restore registers */
 #ifdef CONFIG_8xx_CPU6
-       mfspr   r3, SPRN_DAR
+       mfspr   r3, SPRN_SPRG_SCRATCH2
 #endif
        mtspr   SPRN_DAR, r11   /* Tag DAR */
        EXCEPTION_EPILOG_0