[PATCH v4 03/21] powerpc/8xx: exception InstructionAccess does not exist on MPC8xx

From: Christophe Leroy
Date: Fri Sep 19 2014 - 04:36:23 EST


Exception InstructionAccess does not exist on MPC8xx. No need to branch there from somewhere else.
Handling can be done directly in InstructionTLBError Exception.

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

---
Changes in v2:
- None

Changes in v3:
- arch/powerpc/mm/fault.c uses the vector number, so make sure it understand
the new ones.

Changes in v4:
- Removing the change to mm/fault.c, faking the exception id to make mm/fault
think it comes from InstructionAccess.

arch/powerpc/kernel/head_8xx.S | 15 +++++++--------
1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 3af6db1..ec1958f 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -234,15 +234,10 @@ DataAccess:
EXC_XFER_LITE(0x300, handle_page_fault)

/* Instruction access exception.
- * This is "never generated" by the MPC8xx. We jump to it for other
- * translation errors.
+ * This is "never generated" by the MPC8xx.
*/
. = 0x400
InstructionAccess:
- EXCEPTION_PROLOG
- mr r4,r12
- mr r5,r9
- EXC_XFER_LITE(0x400, handle_page_fault)

/* External interrupt */
EXCEPTION(0x500, HardwareInterrupt, do_IRQ, EXC_XFER_LITE)
@@ -382,7 +377,7 @@ InstructionTLBMiss:
#endif
mfspr r10, SPRN_SPRG_SCRATCH2
EXCEPTION_EPILOG_0
- b InstructionAccess
+ b InstructionTLBError

. = 0x1200
DataStoreTLBMiss:
@@ -477,7 +472,11 @@ DataStoreTLBMiss:
*/
. = 0x1300
InstructionTLBError:
- b InstructionAccess
+ EXCEPTION_PROLOG
+ mr r4,r12
+ mr r5,r9
+ /* 0x400 is InstructionAccess exception, needed by bad_page_fault() */
+ EXC_XFER_LITE(0x400, handle_page_fault)

/* This is the data TLB error on the MPC8xx. This could be due to
* many reasons, including a dirty update to a pte. We can catch that
--
2.1.0

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