From 79feec40dfb643aa3144acf0e3d898cb6e5f2fdb Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Mon, 1 Mar 2021 19:17:17 -0500 Subject: [PATCH] target/arm: Make isar_feature_aa32_fp16_arith() handle M-profile The M-profile definition of the MVFR1 ID register differs slightly from the A-profile one, and in particular the check for "does the CPU support fp16 arithmetic" is not the same. We don't currently implement any M-profile CPUs with fp16 arithmetic, so this is not yet a visible bug, but correcting the logic now disarms this beartrap for when we eventually do. Backports commit dfc523a84b06b6a4b583ed4c29d24fd980dd37a0 --- qemu/target/arm/cpu.h | 31 ++++++++++++++++++++++++++----- 1 file changed, 26 insertions(+), 5 deletions(-) diff --git a/qemu/target/arm/cpu.h b/qemu/target/arm/cpu.h index 48e7af3b..70aa6b1c 100644 --- a/qemu/target/arm/cpu.h +++ b/qemu/target/arm/cpu.h @@ -1672,6 +1672,15 @@ FIELD(ID_MMFR4, LSM, 20, 4) FIELD(ID_MMFR4, CCIDX, 24, 4) FIELD(ID_MMFR4, EVT, 28, 4) +FIELD(ID_PFR1, PROGMOD, 0, 4) +FIELD(ID_PFR1, SECURITY, 4, 4) +FIELD(ID_PFR1, MPROGMOD, 8, 4) +FIELD(ID_PFR1, VIRTUALIZATION, 12, 4) +FIELD(ID_PFR1, GENTIMER, 16, 4) +FIELD(ID_PFR1, SEC_FRAC, 20, 4) +FIELD(ID_PFR1, VIRT_FRAC, 24, 4) +FIELD(ID_PFR1, GIC, 28, 4) + FIELD(ID_AA64ISAR0, AES, 4, 4) FIELD(ID_AA64ISAR0, SHA1, 8, 4) FIELD(ID_AA64ISAR0, SHA2, 12, 4) @@ -1789,10 +1798,12 @@ FIELD(MVFR0, FPROUND, 28, 4) FIELD(MVFR1, FPFTZ, 0, 4) FIELD(MVFR1, FPDNAN, 4, 4) -FIELD(MVFR1, SIMDLS, 8, 4) -FIELD(MVFR1, SIMDINT, 12, 4) -FIELD(MVFR1, SIMDSP, 16, 4) -FIELD(MVFR1, SIMDHP, 20, 4) +FIELD(MVFR1, SIMDLS, 8, 4) /* A-profile only */ +FIELD(MVFR1, SIMDINT, 12, 4) /* A-profile only */ +FIELD(MVFR1, SIMDSP, 16, 4) /* A-profile only */ +FIELD(MVFR1, SIMDHP, 20, 4) /* A-profile only */ +FIELD(MVFR1, MVE, 8, 4) /* M-profile only */ +FIELD(MVFR1, FP16, 20, 4) /* M-profile only */ FIELD(MVFR1, FPHP, 24, 4) FIELD(MVFR1, SIMDFMAC, 28, 4) @@ -3381,9 +3392,19 @@ static inline bool isar_feature_aa32_predinv(const ARMISARegisters *id) return FIELD_EX32(id->id_isar6, ID_ISAR6, SPECRES) != 0; } +static inline bool isar_feature_aa32_mprofile(const ARMISARegisters *id) +{ + return FIELD_EX32(id->id_pfr1, ID_PFR1, MPROGMOD) != 0; +} + static inline bool isar_feature_aa32_fp16_arith(const ARMISARegisters *id) { - return FIELD_EX32(id->mvfr1, MVFR1, FPHP) >= 3; + /* Sadly this is encoded differently for A-profile and M-profile */ + if (isar_feature_aa32_mprofile(id)) { + return FIELD_EX32(id->mvfr1, MVFR1, FP16) > 0; + } else { + return FIELD_EX32(id->mvfr1, MVFR1, FPHP) >= 3; + } } static inline bool isar_feature_aa32_vfp_simd(const ARMISARegisters *id)