[PATCH v4 14/21] powerpc/8xx: Const for TLB RPN forced value

From: Christophe Leroy
Date: Fri Sep 19 2014 - 04:36:48 EST


Value 0x00f0 is used to force bits in TLB level 2 entry. This value is linked
to the page size and will vary when we change the page size. Lets define a const
for it in order to have it at only one place.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>

---
Changes in v2:
- None

Changes in v3:
- None

Changes in v4:
- None

arch/powerpc/kernel/head_8xx.S | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index e8d8263..d777e3c 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -40,6 +40,13 @@
#else
#define DO_8xx_CPU6(val, reg)
#endif
+
+/*
+ * Value for the bits that have fixed value in RPN entries.
+ * Also used for tagging DAR for DTLBerror.
+ */
+#define RPN_PATTERN 0x00f0
+
__HEAD
_ENTRY(_stext);
_ENTRY(_start);
@@ -211,7 +218,7 @@ MachineCheck:
EXCEPTION_PROLOG
mfspr r4,SPRN_DAR
stw r4,_DAR(r11)
- li r5,0x00f0
+ li r5,RPN_PATTERN
mtspr SPRN_DAR,r5 /* Tag DAR, to be used in DTLB Error */
mfspr r5,SPRN_DSISR
stw r5,_DSISR(r11)
@@ -239,7 +246,7 @@ Alignment:
EXCEPTION_PROLOG
mfspr r4,SPRN_DAR
stw r4,_DAR(r11)
- li r5,0x00f0
+ li r5,RPN_PATTERN
mtspr SPRN_DAR,r5 /* Tag DAR, to be used in DTLB Error */
mfspr r5,SPRN_DSISR
stw r5,_DSISR(r11)
@@ -343,7 +350,7 @@ InstructionTLBMiss:
* set. All other Linux PTE bits control the behavior
* of the MMU.
*/
- li r11, 0x00f0
+ li r11, RPN_PATTERN
rlwimi r10, r11, 0, 0x07f8 /* Set 24-27, clear 21-23,28 */
DO_8xx_CPU6(0x2d80, r3)
mtspr SPRN_MI_RPN, r10 /* Update TLB entry */
@@ -447,7 +454,7 @@ DataStoreTLBMiss:
* set. All other Linux PTE bits control the behavior
* of the MMU.
*/
-2: li r11, 0x00f0
+2: li r11, RPN_PATTERN
rlwimi r10, r11, 0, 24, 28 /* Set 24-27, clear 28 */
DO_8xx_CPU6(0x3d80, r3)
mtspr SPRN_MD_RPN, r10 /* Update TLB entry */
@@ -482,7 +489,7 @@ DataTLBError:
EXCEPTION_PROLOG_0

mfspr r11, SPRN_DAR
- cmpwi cr0, r11, 0x00f0
+ cmpwi cr0, r11, RPN_PATTERN
beq- FixupDAR /* must be a buggy dcbX, icbi insn. */
DARFixed:/* Return from dcbx instruction bug workaround */
EXCEPTION_PROLOG_1
@@ -491,7 +498,7 @@ DARFixed:/* Return from dcbx instruction bug workaround */
stw r10,_DSISR(r11)
mr r5,r10
mfspr r4,SPRN_DAR
- li r10,0x00f0
+ li r10,RPN_PATTERN
mtspr SPRN_DAR,r10 /* Tag DAR, to be used in DTLB Error */
/* 0x300 is DataAccess exception, needed by bad_page_fault() */
EXC_XFER_LITE(0x300, handle_page_fault)
--
2.1.0

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