target/arm: Add cpu properties for enabling FEAT_RME

Add an x-rme cpu property to enable FEAT_RME.
Add an x-l0gptsz property to set GPCCR_EL3.L0GPTSZ,
for testing various possible configurations.

We're not currently completely sure whether FEAT_RME will
be OK to enable purely as a CPU-level property, or if it will
need board co-operation, so we're making these experimental
x- properties, so that the people developing the system
level software for RME can try to start using this and let
us know how it goes. The command line syntax for enabling
this will change in future, without backwards-compatibility.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230620124418.805717-21-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

target/arm/tcg/cpu64.c

@@ -142,6 +142,56 @@ static void cpu_max_set_sve_max_vq(Object *obj, Visitor *v, const char *name,
     cpu->sve_max_vq = max_vq;
 }
 
+static bool cpu_arm_get_rme(Object *obj, Error **errp)
+{
+    ARMCPU *cpu = ARM_CPU(obj);
+    return cpu_isar_feature(aa64_rme, cpu);
+}
+
+static void cpu_arm_set_rme(Object *obj, bool value, Error **errp)
+{
+    ARMCPU *cpu = ARM_CPU(obj);
+    uint64_t t;
+
+    t = cpu->isar.id_aa64pfr0;
+    t = FIELD_DP64(t, ID_AA64PFR0, RME, value);
+    cpu->isar.id_aa64pfr0 = t;
+}
+
+static void cpu_max_set_l0gptsz(Object *obj, Visitor *v, const char *name,
+                                void *opaque, Error **errp)
+{
+    ARMCPU *cpu = ARM_CPU(obj);
+    uint32_t value;
+
+    if (!visit_type_uint32(v, name, &value, errp)) {
+        return;
+    }
+
+    /* Encode the value for the GPCCR_EL3 field. */
+    switch (value) {
+    case 30:
+    case 34:
+    case 36:
+    case 39:
+        cpu->reset_l0gptsz = value - 30;
+        break;
+    default:
+        error_setg(errp, "invalid value for l0gptsz");
+        error_append_hint(errp, "valid values are 30, 34, 36, 39\n");
+        break;
+    }
+}
+
+static void cpu_max_get_l0gptsz(Object *obj, Visitor *v, const char *name,
+                                void *opaque, Error **errp)
+{
+    ARMCPU *cpu = ARM_CPU(obj);
+    uint32_t value = cpu->reset_l0gptsz + 30;
+
+    visit_type_uint32(v, name, &value, errp);
+}
+
 static Property arm_cpu_lpa2_property =
     DEFINE_PROP_BOOL("lpa2", ARMCPU, prop_lpa2, true);
 
@@ -700,6 +750,9 @@ void aarch64_max_tcg_initfn(Object *obj)
     aarch64_add_sme_properties(obj);
     object_property_add(obj, "sve-max-vq", "uint32", cpu_max_get_sve_max_vq,
                         cpu_max_set_sve_max_vq, NULL, NULL);
+    object_property_add_bool(obj, "x-rme", cpu_arm_get_rme, cpu_arm_set_rme);
+    object_property_add(obj, "x-l0gptsz", "uint32", cpu_max_get_l0gptsz,
+                        cpu_max_set_l0gptsz, NULL, NULL);
     qdev_property_add_static(DEVICE(obj), &arm_cpu_lpa2_property);
 }