| Message ID | 1473419765-3437-3-git-send-email-will.deacon@arm.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index d5025c69ca81..43a75e2fe931 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -87,6 +87,15 @@ .endm /* + * NOP sequence + */ + .macro nops, num + .rept \num + nop + .endr + .endm + +/* * Emit an entry into the exception table */ .macro _asm_extable, from, to diff --git a/arch/arm64/include/asm/barrier.h b/arch/arm64/include/asm/barrier.h index 4eea7f618dce..4e0497f581a0 100644 --- a/arch/arm64/include/asm/barrier.h +++ b/arch/arm64/include/asm/barrier.h @@ -20,6 +20,9 @@ #ifndef __ASSEMBLY__ +#define __nops(n) ".rept " #n "\nnop\n.endr\n" +#define nops(n) asm volatile(__nops(n)) + #define sev() asm volatile("sev" : : : "memory") #define wfe() asm volatile("wfe" : : : "memory") #define wfi() asm volatile("wfi" : : : "memory")
NOP sequences tend to get used for padding out alternative sections and uarch-specific pipeline flushes in errata workarounds. This patch adds macros for generating these sequences as both inline asm blocks, but also as strings suitable for embedding in other asm blocks directly. Signed-off-by: Will Deacon <will.deacon@arm.com> --- arch/arm64/include/asm/assembler.h | 9 +++++++++ arch/arm64/include/asm/barrier.h | 3 +++ 2 files changed, 12 insertions(+) -- 2.1.4 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel