By default, TASK_SIZE is set to 0x80000000 for PPC_8xx, which is most
likely sufficient for most cases. However, kernel configuration allows
to set TASK_SIZE to another value, so the 8xx shall handle it.
This patch also takes into account the case of PAGE_OFFSET lower than
0x80000000, allthought most of the time it is equal to 0xC0000000
Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr>
---
arch/powerpc/kernel/head_8xx.S | 25 +++++++++++++++++++------
1 file changed, 19 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index ba2dc53..c640bbb 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -48,6 +48,19 @@
mtspr spr, reg
#endif
+/* Macro to test if an address is a kernel address */
+#if CONFIG_TASK_SIZE <= 0x80000000 && CONFIG_PAGE_OFFSET >= 0x80000000
+#define IS_KERNEL(tmp, addr) \
+ andis. tmp, addr, 0x8000 /* Address >= 0x80000000 */
+#define BRANCH_UNLESS_KERNEL(label) beq label
+#else
+#define IS_KERNEL(tmp, addr) \
+ rlwinm tmp, addr, 16, 16, 31; \
+ cmpli cr0, tmp, PAGE_OFFSET >> 16
+#define BRANCH_UNLESS_KERNEL(label) blt label
+#endif
+
+
/*
* Value for the bits that have fixed value in RPN entries.
* Also used for tagging DAR for DTLBerror.
@@ -322,9 +335,9 @@ InstructionTLBMiss:
mfspr r11, SPRN_SRR0 /* Get effective address of fault */
INVALIDATE_ADJACENT_PAGES_CPU15(r10, r11)
mfcr r10
- andis. r11, r11, 0x8000 /* Address >= 0x80000000 */
+ IS_KERNEL(r11, r11)
mfspr r11, SPRN_M_TW /* Get level 1 table */
- beq 3f
+ BRANCH_UNLESS_KERNEL(3f)
lis r11, (swapper_pg_dir-PAGE_OFFSET)@ha
3:
mtcr r10
@@ -379,9 +392,9 @@ DataStoreTLBMiss:
* kernel page tables.
*/
mfspr r11, SPRN_MD_EPN
- andis. r11, r11, 0x8000
+ IS_KERNEL(r11, r11)
mfspr r11, SPRN_M_TW /* Get level 1 table */
- beq 3f
+ BRANCH_UNLESS_KERNEL(3f)
lis r11, (swapper_pg_dir-PAGE_OFFSET)@ha
3:
mtcr r10
@@ -513,9 +526,9 @@ FixupDAR:/* Entry point for dcbx workaround. */
mtspr SPRN_SPRG_SCRATCH2, r10
/* fetch instruction from memory. */
mfspr r10, SPRN_SRR0
- andis. r11, r10, 0x8000 /* Address >= 0x80000000 */
+ IS_KERNEL(r11, r10)
mfspr r11, SPRN_M_TW /* Get level 1 table */
- beq 3f
+ BRANCH_UNLESS_KERNEL(3f)
lis r11, (swapper_pg_dir-PAGE_OFFSET)@ha
/* Insert level 1 index */
3: rlwimi r11, r10, 32 - ((PAGE_SHIFT - 2) << 1), (PAGE_SHIFT - 2) << 1,
29
--
2.1.0
--
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