target/arm: Enable FEAT_IESB for -cpu max

This feature is AArch64 only, and applies to physical SErrors,
which QEMU does not implement, thus the feature is a nop.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220506180242.216785-19-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

docs/system/arm/emulation.rst

@@ -25,6 +25,7 @@ the following architecture extensions:
 - FEAT_FlagM2 (Enhancements to flag manipulation instructions)
 - FEAT_HPDS (Hierarchical permission disables)
 - FEAT_I8MM (AArch64 Int8 matrix multiplication instructions)
+- FEAT_IESB (Implicit error synchronization event)
 - FEAT_JSCVT (JavaScript conversion instructions)
 - FEAT_LOR (Limited ordering regions)
 - FEAT_LPA (Large Physical Address space)

target/arm/cpu64.c

@@ -781,6 +781,7 @@ static void aarch64_max_initfn(Object *obj)
     t = cpu->isar.id_aa64mmfr2;
     t = FIELD_DP64(t, ID_AA64MMFR2, CNP, 1);      /* FEAT_TTCNP */
     t = FIELD_DP64(t, ID_AA64MMFR2, UAO, 1);      /* FEAT_UAO */
+    t = FIELD_DP64(t, ID_AA64MMFR2, IESB, 1);     /* FEAT_IESB */
     t = FIELD_DP64(t, ID_AA64MMFR2, VARANGE, 1);  /* FEAT_LVA */
     t = FIELD_DP64(t, ID_AA64MMFR2, ST, 1);       /* FEAT_TTST */
     t = FIELD_DP64(t, ID_AA64MMFR2, TTL, 1);      /* FEAT_TTL */