diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index 0cf9eacebe..b9b33bc285 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -495,6 +495,9 @@ typedef struct CPUARMState {
         uint64_t pmccfiltr_el0; /* Performance Monitor Filter Register */
         uint64_t vpidr_el2; /* Virtualization Processor ID Register */
         uint64_t vmpidr_el2; /* Virtualization Multiprocessor ID Register */
+        uint64_t tfsr_el[4]; /* tfsrel0_el1 is index 0.  */
+        uint64_t gcr_el1;
+        uint64_t rgsr_el1;
     } cp15;
 
     struct {
diff --git a/target/arm/internals.h b/target/arm/internals.h
index 2922324f63..fbfa770c23 100644
--- a/target/arm/internals.h
+++ b/target/arm/internals.h
@@ -1002,4 +1002,10 @@ static inline bool allocation_tag_access_enabled(CPUARMState *env, int el,
     return sctlr != 0;
 }
 
+/*
+ * The log2 of the words in the tag block, for GMID_EL1.BS.
+ * The is the maximum, 256 bytes, which manipulates 64-bits of tags.
+ */
+#define GMID_EL1_BS  6
+
 #endif
diff --git a/target/arm/helper.c b/target/arm/helper.c
index ab8006291b..7b30e1a1a9 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -5732,6 +5732,69 @@ static const ARMCPRegInfo pauth_reginfo[] = {
       .fieldoffset = offsetof(CPUARMState, apib_key.hi) },
     REGINFO_SENTINEL
 };
+
+static CPAccessResult access_mte(CPUARMState *env, const ARMCPRegInfo *ri,
+                                 bool isread)
+{
+    int el = arm_current_el(env);
+
+    if (el < 2 &&
+        arm_feature(env, ARM_FEATURE_EL2) &&
+        !(arm_hcr_el2_eff(env) & HCR_ATA)) {
+        return CP_ACCESS_TRAP_EL2;
+    }
+    if (el < 3 &&
+        arm_feature(env, ARM_FEATURE_EL3) &&
+        !(env->cp15.scr_el3 & SCR_ATA)) {
+        return CP_ACCESS_TRAP_EL3;
+    }
+    return CP_ACCESS_OK;
+}
+
+static uint64_t tco_read(CPUARMState *env, const ARMCPRegInfo *ri)
+{
+    return env->pstate & PSTATE_TCO;
+}
+
+static void tco_write(CPUARMState *env, const ARMCPRegInfo *ri, uint64_t val)
+{
+    env->pstate = (env->pstate & ~PSTATE_TCO) | (val & PSTATE_TCO);
+}
+
+static const ARMCPRegInfo mte_reginfo[] = {
+    { .name = "TFSRE0_EL1", .state = ARM_CP_STATE_AA64,
+      .opc0 = 3, .opc1 = 0, .crn = 6, .crm = 6, .opc2 = 1,
+      .access = PL1_RW, .accessfn = access_mte,
+      .fieldoffset = offsetof(CPUARMState, cp15.tfsr_el[0]) },
+    { .name = "TFSR_EL1", .state = ARM_CP_STATE_AA64,
+      .opc0 = 3, .opc1 = 0, .crn = 6, .crm = 5, .opc2 = 0,
+      .access = PL1_RW, .accessfn = access_mte,
+      .fieldoffset = offsetof(CPUARMState, cp15.tfsr_el[1]) },
+    { .name = "TFSR_EL2", .state = ARM_CP_STATE_AA64,
+      .opc0 = 3, .opc1 = 4, .crn = 6, .crm = 5, .opc2 = 0,
+      .access = PL2_RW, .accessfn = access_mte,
+      .fieldoffset = offsetof(CPUARMState, cp15.tfsr_el[2]) },
+    { .name = "TFSR_EL3", .state = ARM_CP_STATE_AA64,
+      .opc0 = 3, .opc1 = 6, .crn = 6, .crm = 6, .opc2 = 0,
+      .access = PL3_RW,
+      .fieldoffset = offsetof(CPUARMState, cp15.tfsr_el[3]) },
+    { .name = "RGSR_EL1", .state = ARM_CP_STATE_AA64,
+      .opc0 = 3, .opc1 = 0, .crn = 1, .crm = 0, .opc2 = 5,
+      .access = PL1_RW, .accessfn = access_mte,
+      .fieldoffset = offsetof(CPUARMState, cp15.rgsr_el1) },
+    { .name = "GCR_EL1", .state = ARM_CP_STATE_AA64,
+      .opc0 = 3, .opc1 = 0, .crn = 1, .crm = 0, .opc2 = 6,
+      .access = PL1_RW, .accessfn = access_mte,
+      .fieldoffset = offsetof(CPUARMState, cp15.gcr_el1) },
+    { .name = "TCO", .state = ARM_CP_STATE_AA64,
+      .opc0 = 3, .opc1 = 3, .crn = 4, .crm = 2, .opc2 = 7,
+      .type = ARM_CP_NO_RAW,
+      .access = PL0_RW, .readfn = tco_read, .writefn = tco_write },
+    { .name = "GMID_EL1", .state = ARM_CP_STATE_AA64,
+      .opc0 = 3, .opc1 = 1, .crn = 0, .crm = 0, .opc2 = 4,
+      .access = PL1_R, .type = ARM_CP_CONST, .resetvalue = GMID_EL1_BS },
+    REGINFO_SENTINEL
+};
 #endif
 
 static CPAccessResult access_predinv(CPUARMState *env, const ARMCPRegInfo *ri,
@@ -6676,6 +6739,9 @@ void register_cp_regs_for_features(ARMCPU *cpu)
     if (cpu_isar_feature(aa64_pauth, cpu)) {
         define_arm_cp_regs(cpu, pauth_reginfo);
     }
+    if (cpu_isar_feature(aa64_mte_insn_reg, cpu)) {
+        define_arm_cp_regs(cpu, mte_reginfo);
+    }
 #endif
 
     /*
diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index d971b57037..128b7f2e32 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -1746,6 +1746,17 @@ static void handle_msr_i(DisasContext *s, uint32_t insn,
         s->base.is_jmp = DISAS_UPDATE;
         break;
 
+    case 0x1c: /* TCO */
+        if (!dc_isar_feature(aa64_mte_insn_reg, s)) {
+            goto do_unallocated;
+        }
+        if (crm & 1) {
+            set_pstate_bits(PSTATE_TCO);
+        } else {
+            clear_pstate_bits(PSTATE_TCO);
+        }
+        break;
+
     default:
     do_unallocated:
         unallocated_encoding(s);
