The ARMv8.1-Atomics feature (renamed FEAT_LSE in more modern versions
of the Arm ARM) has always ben indicated by ID_AA64ISAR0.ATOMIC being
0b0010 or greater; 0b0001 is a reserved unused value.
We were incorrectly checking for != 0; this had no harmful effects
because all the CPUs set their value for this field to either 0
(for not having the feature) or 2 (if they do have it), but it's
better to match what the architecture specifies here.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20250819145659.2165160-1-peter.maydell@linaro.org
---
target/arm/cpu-features.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/target/arm/cpu-features.h b/target/arm/cpu-features.h
index 41511d08350..d48754bcf27 100644
--- a/target/arm/cpu-features.h
+++ b/target/arm/cpu-features.h
@@ -408,7 +408,7 @@ static inline bool isar_feature_aa64_crc32(const ARMISARegisters *id)
static inline bool isar_feature_aa64_atomics(const ARMISARegisters *id)
{
- return FIELD_EX64_IDREG(id, ID_AA64ISAR0, ATOMIC) != 0;
+ return FIELD_EX64_IDREG(id, ID_AA64ISAR0, ATOMIC) >= 2;
}
static inline bool isar_feature_aa64_rdm(const ARMISARegisters *id)
--
2.43.0