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authorScott Wood <scottwood@freescale.com>2007-06-25 21:50:41 +0200
committerKumar Gala <galak@kernel.crashing.org>2007-10-04 03:36:36 +0200
commit7401685242fbcbf4b0660726372c77a88c4af17d (patch)
tree71b814468d705c2c48184161c38a0295c832239d /arch/powerpc/kernel/head_8xx.S
parent[POWERPC] 8xx: Add pin and clock setting functions. (diff)
downloadlinux-7401685242fbcbf4b0660726372c77a88c4af17d.tar.xz
linux-7401685242fbcbf4b0660726372c77a88c4af17d.zip
[POWERPC] 8xx: Work around CPU15 erratum.
The CPU15 erratum on MPC8xx chips can cause incorrect code execution under certain circumstances, where there is a conditional or indirect branch in the last word of a page, with a target in the last cache line of the next page. This patch implements one of the suggested workarounds, by forcing a TLB miss whenever execution crosses a page boundary. This is done by invalidating the pages before and after the one being loaded into the TLB in the ITLB miss handler. Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/kernel/head_8xx.S')
-rw-r--r--arch/powerpc/kernel/head_8xx.S6
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 9c30938aad52..f7458396cd7c 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -298,6 +298,12 @@ InstructionTLBMiss:
stw r10, 0(r0)
stw r11, 4(r0)
mfspr r10, SPRN_SRR0 /* Get effective address of fault */
+#ifdef CONFIG_8xx_CPU15
+ addi r11, r10, 0x1000
+ tlbie r11
+ addi r11, r10, -0x1000
+ tlbie r11
+#endif
DO_8xx_CPU6(0x3780, r3)
mtspr SPRN_MD_EPN, r10 /* Have to use MD_EPN for walk, MI_EPN can't */
mfspr r10, SPRN_M_TWB /* Get level 1 table entry address */