[PATCH v3 03/21] powerpc/8xx: exception InstructionAccess does not exist on MPC8xx

From: Christophe Leroy
Date: Wed Sep 17 2014 - 12:40:01 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.

arch/powerpc/kernel/head_8xx.S | 17 +++++++----------
arch/powerpc/mm/fault.c | 1 +
2 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 3af6db1..fbe5d10 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -234,15 +234,9 @@ 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)
+ EXCEPTION(0x400, InstructionAccess, unknown_exception, EXC_XFER_STD)

/* External interrupt */
EXCEPTION(0x500, HardwareInterrupt, do_IRQ, EXC_XFER_LITE)
@@ -382,7 +376,7 @@ InstructionTLBMiss:
#endif
mfspr r10, SPRN_SPRG_SCRATCH2
EXCEPTION_EPILOG_0
- b InstructionAccess
+ b InstructionTLBError

. = 0x1200
DataStoreTLBMiss:
@@ -477,7 +471,10 @@ DataStoreTLBMiss:
*/
. = 0x1300
InstructionTLBError:
- b InstructionAccess
+ EXCEPTION_PROLOG
+ mr r4,r12
+ mr r5,r9
+ EXC_XFER_LITE(0x1300, 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
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 51ab9e7..4d63c96 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -526,6 +526,7 @@ void bad_page_fault(struct pt_regs *regs, unsigned long address, int sig)
break;
case 0x400:
case 0x480:
+ case 0x1300:
printk(KERN_ALERT "Unable to handle kernel paging request for "
"instruction fetch\n");
break;
--
2.1.0

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