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Subject[PATCH] arm64: assembler: Fine-tune code to improve code readability
Date
This patch tweaks the code to improve readability.

Defined values are:
PMUVer == 0b0000 : Performance Monitors Extension not implemented.

Signed-off-by: Zhiyuan Dai <daizhiyuan@phytium.com.cn>
---
arch/arm64/include/asm/assembler.h | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h
index 6ebdc0f..efd43a1 100644
--- a/arch/arm64/include/asm/assembler.h
+++ b/arch/arm64/include/asm/assembler.h
@@ -489,11 +489,10 @@
*/
.macro reset_pmuserenr_el0, tmpreg
mrs \tmpreg, id_aa64dfr0_el1
- sbfx \tmpreg, \tmpreg, #ID_AA64DFR0_PMUVER_SHIFT, #4
- cmp \tmpreg, #1 // Skip if no PMU present
- b.lt 9000f
- msr pmuserenr_el0, xzr // Disable PMU access from EL0
-9000:
+ ubfx \tmpreg, \tmpreg, #ID_AA64DFR0_PMUVER_SHIFT, #4
+ cbz \tmpreg, .Lskip_pmu_\@ // Skip if no PMU present
+ msr_s SYS_PMUSERENR_EL0, xzr // Disable PMU access from EL0
+.Lskip_pmu_\@:
.endm

/*
--
1.8.3.1
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