[PATCH v2 1/3] powerpc/8xx: use r3 to scratch CR in ITLBmiss

From: Christophe Leroy
Date: Fri Sep 16 2016 - 03:02:49 EST


Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
arch/powerpc/kernel/head_8xx.S | 21 +++++++++------------
1 file changed, 9 insertions(+), 12 deletions(-)

diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 8632515..fd5b53d 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -323,7 +323,7 @@ SystemCall:
#endif

InstructionTLBMiss:
-#ifdef CONFIG_8xx_CPU6
+#if defined(CONFIG_8xx_CPU6) || defined(CONFIG_MODULES) || defined (CONFIG_DEBUG_PAGEALLOC)
mtspr SPRN_SPRG_SCRATCH2, r3
#endif
EXCEPTION_PROLOG_0
@@ -331,23 +331,20 @@ InstructionTLBMiss:
/* If we are faulting a kernel address, we have to use the
* kernel page tables.
*/
+ mfspr r10, SPRN_SRR0 /* Get effective address of fault */
+ INVALIDATE_ADJACENT_PAGES_CPU15(r11, r10)
#if defined(CONFIG_MODULES) || defined (CONFIG_DEBUG_PAGEALLOC)
/* Only modules will cause ITLB Misses as we always
* pin the first 8MB of kernel memory */
- mfspr r11, SPRN_SRR0 /* Get effective address of fault */
- INVALIDATE_ADJACENT_PAGES_CPU15(r10, r11)
- mfcr r10
- IS_KERNEL(r11, r11)
+ mfcr r3
+ IS_KERNEL(r11, r10)
+#endif
mfspr r11, SPRN_M_TW /* Get level 1 table */
+#if defined(CONFIG_MODULES) || defined (CONFIG_DEBUG_PAGEALLOC)
BRANCH_UNLESS_KERNEL(3f)
lis r11, (swapper_pg_dir-PAGE_OFFSET)@ha
3:
- mtcr r10
- mfspr r10, SPRN_SRR0 /* Get effective address of fault */
-#else
- mfspr r10, SPRN_SRR0 /* Get effective address of fault */
- INVALIDATE_ADJACENT_PAGES_CPU15(r11, r10)
- mfspr r11, SPRN_M_TW /* Get level 1 table base address */
+ mtcr r3
#endif
/* Insert level 1 index */
rlwimi r11, r10, 32 - ((PAGE_SHIFT - 2) << 1), (PAGE_SHIFT - 2) << 1, 29
@@ -379,7 +376,7 @@ InstructionTLBMiss:
MTSPR_CPU6(SPRN_MI_RPN, r10, r3) /* Update TLB entry */

/* Restore registers */
-#ifdef CONFIG_8xx_CPU6
+#if defined(CONFIG_8xx_CPU6) || defined(CONFIG_MODULES) || defined (CONFIG_DEBUG_PAGEALLOC)
mfspr r3, SPRN_SPRG_SCRATCH2
#endif
EXCEPTION_EPILOG_0
--
2.1.0