From 669474e772b952b14f4de4845a1558fd4c0414a4 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Mon, 5 Feb 2018 15:34:16 +0000 Subject: arm64: barrier: Add CSDB macros to control data-value prediction For CPUs capable of data value prediction, CSDB waits for any outstanding predictions to architecturally resolve before allowing speculative execution to continue. Provide macros to expose it to the arch code. Reviewed-by: Mark Rutland Signed-off-by: Will Deacon Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/assembler.h | 7 +++++++ arch/arm64/include/asm/barrier.h | 1 + 2 files changed, 8 insertions(+) (limited to 'arch') diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 544878a9f29e..1f44b4255a28 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -115,6 +115,13 @@ hint #16 .endm +/* + * Value prediction barrier + */ + .macro csdb + hint #20 + .endm + /* * NOP sequence */ diff --git a/arch/arm64/include/asm/barrier.h b/arch/arm64/include/asm/barrier.h index 77651c49ef44..c0a846d2c602 100644 --- a/arch/arm64/include/asm/barrier.h +++ b/arch/arm64/include/asm/barrier.h @@ -32,6 +32,7 @@ #define dsb(opt) asm volatile("dsb " #opt : : : "memory") #define psb_csync() asm volatile("hint #17" : : : "memory") +#define csdb() asm volatile("hint #20" : : : "memory") #define mb() dsb(sy) #define rmb() dsb(ld) -- cgit v1.2.3-59-g8ed1b