[PATCH 21/35] target/arm: Add FEAT_NV to max, neoverse-n2, neoverse-v1 CPUs

[Peter Maydell]

Enable FEAT_NV on the 'max' CPU, and stop filtering it out for the
Neoverse N2 and Neoverse V1 CPUs.  We continue to downgrade FEAT_NV2
support to FEAT_NV for the latter two CPU types.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 docs/system/arm/emulation.rst | 1 +
 target/arm/cpu.c              | 8 +++++---
 target/arm/tcg/cpu64.c        | 1 +
 3 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/docs/system/arm/emulation.rst b/docs/system/arm/emulation.rst
index 0b604f90059..d827b42de79 100644
--- a/docs/system/arm/emulation.rst
+++ b/docs/system/arm/emulation.rst
@@ -63,6 +63,7 @@ the following architecture extensions:
 - FEAT_MTE (Memory Tagging Extension)
 - FEAT_MTE2 (Memory Tagging Extension)
 - FEAT_MTE3 (MTE Asymmetric Fault Handling)
+- FEAT_NV (Nested Virtualization)
 - FEAT_PACIMP (Pointer authentication - IMPLEMENTATION DEFINED algorithm)
 - FEAT_PACQARMA3 (Pointer authentication - QARMA3 algorithm)
 - FEAT_PACQARMA5 (Pointer authentication - QARMA5 algorithm)
diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index efb22a87f9e..da0c02f850b 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -2238,9 +2238,11 @@ static void arm_cpu_realizefn(DeviceState *dev, Error 
**errp)
         /* 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);
+        /* FEAT_NV2 (Enhanced Nested Virtualization support) */
+        if (FIELD_EX64(cpu->isar.id_aa64mmfr2, ID_AA64MMFR2, NV) > 1) {
+            cpu->isar.id_aa64mmfr2 =
+                FIELD_DP64(cpu->isar.id_aa64mmfr2, ID_AA64MMFR2, NV, 1);
+        }
     }
 
     /* MPU can be configured out of a PMSA CPU either by setting has-mpu
diff --git a/target/arm/tcg/cpu64.c b/target/arm/tcg/cpu64.c
index 40e7a45166f..93f040e6e96 100644
--- a/target/arm/tcg/cpu64.c
+++ b/target/arm/tcg/cpu64.c
@@ -1204,6 +1204,7 @@ void aarch64_max_tcg_initfn(Object *obj)
     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, NV, 1);       /* FEAT_NV */
     t = FIELD_DP64(t, ID_AA64MMFR2, ST, 1);       /* FEAT_TTST */
     t = FIELD_DP64(t, ID_AA64MMFR2, AT, 1);       /* FEAT_LSE2 */
     t = FIELD_DP64(t, ID_AA64MMFR2, IDS, 1);      /* FEAT_IDST */
-- 
2.34.1