[PATCH 07/52] arm64: Factor out TTBR0_EL1 post-update workaround into a specific asm macro

From: Alex Shi
Date: Mon Feb 26 2018 - 03:38:12 EST


From: Catalin Marinas <catalin.marinas@xxxxxxx>

commit f33bcf03e6 upstream

This patch takes the errata workaround code out of cpu_do_switch_mm into
a dedicated post_ttbr0_update_workaround macro which will be reused in a
subsequent patch.

Cc: Will Deacon <will.deacon@xxxxxxx>
Cc: James Morse <james.morse@xxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Reviewed-by: Mark Rutland <mark.rutland@xxxxxxx>
Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxx>
---
arch/arm64/include/asm/assembler.h | 13 +++++++++++++
arch/arm64/mm/proc.S | 6 +-----
2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h
index 8760300..ab3a179 100644
--- a/arch/arm64/include/asm/assembler.h
+++ b/arch/arm64/include/asm/assembler.h
@@ -420,4 +420,17 @@ alternative_endif
movk \reg, :abs_g0_nc:\val
.endm

+/*
+ * Errata workaround post TTBR0_EL1 update.
+ */
+ .macro post_ttbr0_update_workaround
+#ifdef CONFIG_CAVIUM_ERRATUM_27456
+alternative_if ARM64_WORKAROUND_CAVIUM_27456
+ ic iallu
+ dsb nsh
+ isb
+alternative_else_nop_endif
+#endif
+ .endm
+
#endif /* __ASM_ASSEMBLER_H */
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index 352c73b..c2adb0c 100644
--- a/arch/arm64/mm/proc.S
+++ b/arch/arm64/mm/proc.S
@@ -136,11 +136,7 @@ ENTRY(cpu_do_switch_mm)
bfi x0, x1, #48, #16 // set the ASID
msr ttbr0_el1, x0 // set TTBR0
isb
-alternative_if ARM64_WORKAROUND_CAVIUM_27456
- ic iallu
- dsb nsh
- isb
-alternative_else_nop_endif
+ post_ttbr0_update_workaround
ret
ENDPROC(cpu_do_switch_mm)

--
2.7.4