FEAT_Spec_FPACC is a feature describing speculative behaviour in the event of a PAC authontication failure when FEAT_FPACCOMBINE is implemented. FEAT_Spec_FPACC means that the speculative use of pointers processed by a PAC Authentication is not materially different in terms of the impact on cached microarchitectural state (caches, TLBs, etc) between passing and failing of the PAC Authentication.
QEMU doesn't do speculative execution, so we can advertise this feature. Signed-off-by: Peter Maydell <peter.mayd...@linaro.org> Reviewed-by: Richard Henderson <richard.hender...@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <phi...@linaro.org> Message-id: 20240418152004.2106516-6-peter.mayd...@linaro.org --- docs/system/arm/emulation.rst | 1 + target/arm/tcg/cpu64.c | 4 ++++ 2 files changed, 5 insertions(+) diff --git a/docs/system/arm/emulation.rst b/docs/system/arm/emulation.rst index 307539cff91..7fcea54d8db 100644 --- a/docs/system/arm/emulation.rst +++ b/docs/system/arm/emulation.rst @@ -61,6 +61,7 @@ the following architecture extensions: - FEAT_FP16 (Half-precision floating-point data processing) - FEAT_FPAC (Faulting on AUT* instructions) - FEAT_FPACCOMBINE (Faulting on combined pointer authentication instructions) +- FEAT_FPACC_SPEC (Speculative behavior of combined pointer authentication instructions) - FEAT_FRINTTS (Floating-point to integer instructions) - FEAT_FlagM (Flag manipulation instructions v2) - FEAT_FlagM2 (Enhancements to flag manipulation instructions) diff --git a/target/arm/tcg/cpu64.c b/target/arm/tcg/cpu64.c index ebb585afd85..443cffe3a85 100644 --- a/target/arm/tcg/cpu64.c +++ b/target/arm/tcg/cpu64.c @@ -1217,6 +1217,10 @@ void aarch64_max_tcg_initfn(Object *obj) t = FIELD_DP64(t, ID_AA64MMFR2, E0PD, 1); /* FEAT_E0PD */ cpu->isar.id_aa64mmfr2 = t; + t = cpu->isar.id_aa64mmfr3; + t = FIELD_DP64(t, ID_AA64MMFR3, SPEC_FPACC, 1); /* FEAT_FPACC_SPEC */ + cpu->isar.id_aa64mmfr3 = t; + t = cpu->isar.id_aa64zfr0; t = FIELD_DP64(t, ID_AA64ZFR0, SVEVER, 1); t = FIELD_DP64(t, ID_AA64ZFR0, AES, 2); /* FEAT_SVE_PMULL128 */ -- 2.34.1