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target/arm: Suppress more TCG unimplemented features in ID registers

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We already squash the ID register field for FEAT_SPE (the Statistical
Profiling Extension) because TCG does not implement it and if we
advertise it to the guest the guest will crash trying to look at
non-existent system registers.  Do the same for some other features
which a real hardware Neoverse-V1 implements but which TCG doesn't:
 * FEAT_TRF (Self-hosted Trace Extension)
 * Trace Macrocell system register access
 * Memory mapped trace
 * FEAT_AMU (Activity Monitors Extension)
 * FEAT_MPAM (Memory Partitioning and Monitoring Extension)
 * FEAT_NV (Nested Virtualization)

Most of these, like FEAT_SPE, are "introspection/trace" type features
which QEMU is unlikely to ever implement.  The odd-one-out here is
FEAT_NV -- we could implement that and at some point we probably
will.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20230704130647.2842917-2-peter.maydell@linaro.org
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Peter Maydell 2023-07-04 14:06:46 +01:00
parent ad18376b90
commit 7d8c283e10
1 changed files with 29 additions and 4 deletions
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33
target/arm/cpu.c
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@ -2069,13 +2069,38 @@ static void arm_cpu_realizefn(DeviceState *dev, Error **errp)
if (tcg_enabled()) {
/*
* Don't report the Statistical Profiling Extension in the ID
* registers, because TCG doesn't implement it yet (not even a
* minimal stub version) and guests will fall over when they
* try to access the non-existent system registers for it.
* Don't report some architectural features in the ID registers
* where TCG does not yet implement it (not even a minimal
* stub version). This avoids guests falling over when they
* try to access the non-existent system registers for them.
*/
/* FEAT_SPE (Statistical Profiling Extension) */
cpu->isar.id_aa64dfr0 =
FIELD_DP64(cpu->isar.id_aa64dfr0, ID_AA64DFR0, PMSVER, 0);
/* FEAT_TRF (Self-hosted Trace Extension) */
cpu->isar.id_aa64dfr0 =
FIELD_DP64(cpu->isar.id_aa64dfr0, ID_AA64DFR0, TRACEFILT, 0);
cpu->isar.id_dfr0 =
FIELD_DP32(cpu->isar.id_dfr0, ID_DFR0, TRACEFILT, 0);
/* Trace Macrocell system register access */
cpu->isar.id_aa64dfr0 =
FIELD_DP64(cpu->isar.id_aa64dfr0, ID_AA64DFR0, TRACEVER, 0);
cpu->isar.id_dfr0 =
FIELD_DP32(cpu->isar.id_dfr0, ID_DFR0, COPTRC, 0);
/* Memory mapped trace */
cpu->isar.id_dfr0 =
FIELD_DP32(cpu->isar.id_dfr0, ID_DFR0, MMAPTRC, 0);
/* FEAT_AMU (Activity Monitors Extension) */
cpu->isar.id_aa64pfr0 =
FIELD_DP64(cpu->isar.id_aa64pfr0, ID_AA64PFR0, AMU, 0);
cpu->isar.id_pfr0 =
FIELD_DP32(cpu->isar.id_pfr0, ID_PFR0, AMU, 0);
/* FEAT_MPAM (Memory Partitioning and Monitoring Extension) */
cpu->isar.id_aa64pfr0 =
FIELD_DP64(cpu->isar.id_aa64pfr0, ID_AA64PFR0, MPAM, 0);
/* FEAT_NV (Nested Virtualization) */
cpu->isar.id_aa64mmfr2 =
FIELD_DP64(cpu->isar.id_aa64mmfr2, ID_AA64MMFR2, NV, 0);
}
/* MPU can be configured out of a PMSA CPU either by setting has-mpu