Subject: [PATCH v4 01/21] powerpc/8xx: Declare SPRG2 as a SCRATCH register

From: Christophe Leroy <[email-masked]>
Date: Fri, 19 Sep 2014 10:36:06 +0200 (CEST)

Since coming 469d62be9263b92f2c3329540cbb1c076111f4f3, SPRG2 is used as a
scratch register just like SPRG0 and SPRG1. So Declare it as such and fix
the comment which is not valid anymore since that commit.

Signed-off-by: Christophe Leroy <[email-masked]>

---
Changes in v2:
- None

Changes in v3:
- None

Changes in v4:
- None

 arch/powerpc/include/asm/reg.h |    3 ++-
 arch/powerpc/kernel/head_8xx.S |   10 +++++-----
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index cb9c174..b6a7d62 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -888,7 +888,7 @@
  * 32-bit 8xx:
  *	- SPRG0 scratch for exception vectors
  *	- SPRG1 scratch for exception vectors
- *	- SPRG2 apparently unused but initialized
+ *	- SPRG2 scratch for exception vectors
  *
  */
 #ifdef CONFIG_PPC64
@@ -994,6 +994,7 @@
 #ifdef CONFIG_8xx
 #define SPRN_SPRG_SCRATCH0	SPRN_SPRG0
 #define SPRN_SPRG_SCRATCH1	SPRN_SPRG1
+#define SPRN_SPRG_SCRATCH2	SPRN_SPRG2
 #endif

diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 55d12fb..1329c5a 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -301,7 +301,7 @@ InstructionTLBMiss:
 	stw	r11, 4(r0)
 #else
 	mtspr	SPRN_DAR, r10
-	mtspr	SPRN_SPRG2, r11
+	mtspr	SPRN_SPRG_SCRATCH2, r11
 #endif
 	mfspr	r10, SPRN_SRR0	/* Get effective address of fault */
 #ifdef CONFIG_8xx_CPU15
@@ -363,7 +363,7 @@ InstructionTLBMiss:
 	mfspr	r10, SPRN_DAR
 	mtcr	r10
 	mtspr	SPRN_DAR, r11	/* Tag DAR */
-	mfspr	r11, SPRN_SPRG2
+	mfspr	r11, SPRN_SPRG_SCRATCH2
 #else
 	lwz	r11, 0(r0)
 	mtcr	r11
@@ -386,7 +386,7 @@ InstructionTLBMiss:
 	mtcr	r10
 	li	r11, 0x00f0
 	mtspr	SPRN_DAR, r11	/* Tag DAR */
-	mfspr	r11, SPRN_SPRG2
+	mfspr	r11, SPRN_SPRG_SCRATCH2
 #else
 	lwz	r11, 0(r0)
 	mtcr	r11
@@ -409,7 +409,7 @@ DataStoreTLBMiss:
 	stw	r11, 4(r0)
 #else
 	mtspr	SPRN_DAR, r10
-	mtspr	SPRN_SPRG2, r11
+	mtspr	SPRN_SPRG_SCRATCH2, r11
 #endif
 	mfspr	r10, SPRN_M_TWB	/* Get level 1 table entry address */
 
@@ -487,7 +487,7 @@ DataStoreTLBMiss:
 	mfspr	r10, SPRN_DAR
 	mtcr	r10
 	mtspr	SPRN_DAR, r11	/* Tag DAR */
-	mfspr	r11, SPRN_SPRG2
+	mfspr	r11, SPRN_SPRG_SCRATCH2
 #else
 	mtspr	SPRN_DAR, r11	/* Tag DAR */
 	lwz	r11, 0(r0)
-- 
1.7.1