1 files changed, 76 insertions, 5 deletions

diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index e44e18062c..5050e1843a 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -203,6 +203,9 @@ static void arm_cpu_reset(DeviceState *dev)
          * Enable TBI0 and TBI1.  While the real kernel only enables TBI0,
          * turning on both here will produce smaller code and otherwise
          * make no difference to the user-level emulation.
+         *
+         * In sve_probe_page, we assume that this is set.
+         * Do not modify this without other changes.
          */
         env->cp15.tcr_el[1].raw_tcr = (3ULL << 37);
 #else
@@ -1249,6 +1252,25 @@ void arm_cpu_post_init(Object *obj)
     if (kvm_enabled()) {
         kvm_arm_add_vcpu_properties(obj);
     }
+
+#ifndef CONFIG_USER_ONLY
+    if (arm_feature(&cpu->env, ARM_FEATURE_AARCH64) &&
+        cpu_isar_feature(aa64_mte, cpu)) {
+        object_property_add_link(obj, "tag-memory",
+                                 TYPE_MEMORY_REGION,
+                                 (Object **)&cpu->tag_memory,
+                                 qdev_prop_allow_set_link_before_realize,
+                                 OBJ_PROP_LINK_STRONG);
+
+        if (arm_feature(&cpu->env, ARM_FEATURE_EL3)) {
+            object_property_add_link(obj, "secure-tag-memory",
+                                     TYPE_MEMORY_REGION,
+                                     (Object **)&cpu->secure_tag_memory,
+                                     qdev_prop_allow_set_link_before_realize,
+                                     OBJ_PROP_LINK_STRONG);
+        }
+    }
+#endif
 }
 
 static void arm_cpu_finalizefn(Object *obj)
@@ -1738,18 +1760,43 @@ static void arm_cpu_realizefn(DeviceState *dev, Error **errp)
 #ifndef CONFIG_USER_ONLY
     MachineState *ms = MACHINE(qdev_get_machine());
     unsigned int smp_cpus = ms->smp.cpus;
+    bool has_secure = cpu->has_el3 || arm_feature(env, ARM_FEATURE_M_SECURITY);
 
-    if (cpu->has_el3 || arm_feature(env, ARM_FEATURE_M_SECURITY)) {
-        cs->num_ases = 2;
+    /*
+     * We must set cs->num_ases to the final value before
+     * the first call to cpu_address_space_init.
+     */
+    if (cpu->tag_memory != NULL) {
+        cs->num_ases = 3 + has_secure;
+    } else {
+        cs->num_ases = 1 + has_secure;
+    }
 
+    if (has_secure) {
         if (!cpu->secure_memory) {
             cpu->secure_memory = cs->memory;
         }
         cpu_address_space_init(cs, ARMASIdx_S, "cpu-secure-memory",
                                cpu->secure_memory);
-    } else {
-        cs->num_ases = 1;
     }
+
+    if (cpu->tag_memory != NULL) {
+        cpu_address_space_init(cs, ARMASIdx_TagNS, "cpu-tag-memory",
+                               cpu->tag_memory);
+        if (has_secure) {
+            cpu_address_space_init(cs, ARMASIdx_TagS, "cpu-tag-memory",
+                                   cpu->secure_tag_memory);
+        }
+    } else if (cpu_isar_feature(aa64_mte, cpu)) {
+        /*
+         * Since there is no tag memory, we can't meaningfully support MTE
+         * to its fullest.  To avoid problems later, when we would come to
+         * use the tag memory, downgrade support to insns only.
+         */
+        cpu->isar.id_aa64pfr1 =
+            FIELD_DP64(cpu->isar.id_aa64pfr1, ID_AA64PFR1, MTE, 1);
+    }
+
     cpu_address_space_init(cs, ARMASIdx_NS, "cpu-memory", cs->memory);
 
     /* No core_count specified, default to smp_cpus. */
@@ -1758,6 +1805,30 @@ static void arm_cpu_realizefn(DeviceState *dev, Error **errp)
     }
 #endif
 
+    if (tcg_enabled()) {
+        int dcz_blocklen = 4 << cpu->dcz_blocksize;
+
+        /*
+         * We only support DCZ blocklen that fits on one page.
+         *
+         * Architectually this is always true.  However TARGET_PAGE_SIZE
+         * is variable and, for compatibility with -machine virt-2.7,
+         * is only 1KiB, as an artifact of legacy ARMv5 subpage support.
+         * But even then, while the largest architectural DCZ blocklen
+         * is 2KiB, no cpu actually uses such a large blocklen.
+         */
+        assert(dcz_blocklen <= TARGET_PAGE_SIZE);
+
+        /*
+         * We only support DCZ blocksize >= 2*TAG_GRANULE, which is to say
+         * both nibbles of each byte storing tag data may be written at once.
+         * Since TAG_GRANULE is 16, this means that blocklen must be >= 32.
+         */
+        if (cpu_isar_feature(aa64_mte, cpu)) {
+            assert(dcz_blocklen >= 2 * TAG_GRANULE);
+        }
+    }
+
     qemu_init_vcpu(cs);
     cpu_reset(cs);
 
@@ -2169,8 +2240,8 @@ static void arm_cpu_class_init(ObjectClass *oc, void *data)
     cc->tlb_fill = arm_cpu_tlb_fill;
     cc->debug_excp_handler = arm_debug_excp_handler;
     cc->debug_check_watchpoint = arm_debug_check_watchpoint;
-#if !defined(CONFIG_USER_ONLY)
     cc->do_unaligned_access = arm_cpu_do_unaligned_access;
+#if !defined(CONFIG_USER_ONLY)
     cc->do_transaction_failed = arm_cpu_do_transaction_failed;
     cc->adjust_watchpoint_address = arm_adjust_watchpoint_address;
 #endif /* CONFIG_TCG && !CONFIG_USER_ONLY */