[PATCH v2 12/14] target/arm: Update MSR access to UAO

[Richard Henderson]

Signed-off-by: Richard Henderson <address@hidden>
---
v2: Move reginfo to file scope; avoid setting uao from spsr
    when the feature is not enabled (pmm).
---
 target/arm/cpu.h           |  6 ++++++
 target/arm/helper-a64.c    |  3 +++
 target/arm/helper.c        | 21 +++++++++++++++++++++
 target/arm/translate-a64.c | 14 ++++++++++++++
 4 files changed, 44 insertions(+)

diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index a6a8f74be8..a0ac70e0fb 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -1266,6 +1266,7 @@ void pmu_init(ARMCPU *cpu);
 #define PSTATE_IL (1U << 20)
 #define PSTATE_SS (1U << 21)
 #define PSTATE_PAN (1U << 22)
+#define PSTATE_UAO (1U << 23)
 #define PSTATE_V (1U << 28)
 #define PSTATE_C (1U << 29)
 #define PSTATE_Z (1U << 30)
@@ -3655,6 +3656,11 @@ static inline bool isar_feature_aa64_ats1e1(const 
ARMISARegisters *id)
     return FIELD_EX64(id->id_aa64mmfr1, ID_AA64MMFR1, PAN) >= 2;
 }
 
+static inline bool isar_feature_aa64_uao(const ARMISARegisters *id)
+{
+    return FIELD_EX64(id->id_aa64mmfr2, ID_AA64MMFR2, UAO) != 0;
+}
+
 static inline bool isar_feature_aa64_bti(const ARMISARegisters *id)
 {
     return FIELD_EX64(id->id_aa64pfr1, ID_AA64PFR1, BT) != 0;
diff --git a/target/arm/helper-a64.c b/target/arm/helper-a64.c
index 70d6407f80..9dda94644f 100644
--- a/target/arm/helper-a64.c
+++ b/target/arm/helper-a64.c
@@ -1037,6 +1037,9 @@ void HELPER(exception_return)(CPUARMState *env, uint64_t 
new_pc)
         if (!cpu_isar_feature(aa64_pan, env_archcpu(env))) {
             spsr &= ~PSTATE_PAN;
         }
+        if (!cpu_isar_feature(aa64_uao, env_archcpu(env))) {
+            spsr &= ~PSTATE_UAO;
+        }
         pstate_write(env, spsr);
         if (!arm_singlestep_active(env)) {
             env->pstate &= ~PSTATE_SS;
diff --git a/target/arm/helper.c b/target/arm/helper.c
index a48f37dc05..d847b0f40b 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -4191,6 +4191,24 @@ static const ARMCPRegInfo pan_reginfo = {
     .readfn = aa64_pan_read, .writefn = aa64_pan_write
 };
 
+static uint64_t aa64_uao_read(CPUARMState *env, const ARMCPRegInfo *ri)
+{
+    return env->pstate & PSTATE_UAO;
+}
+
+static void aa64_uao_write(CPUARMState *env, const ARMCPRegInfo *ri,
+                           uint64_t value)
+{
+    env->pstate = (env->pstate & ~PSTATE_UAO) | (value & PSTATE_UAO);
+}
+
+static const ARMCPRegInfo uao_reginfo = {
+    .name = "UAO", .state = ARM_CP_STATE_AA64,
+    .opc0 = 3, .opc1 = 0, .crn = 4, .crm = 2, .opc2 = 4,
+    .type = ARM_CP_NO_RAW, .access = PL1_RW,
+    .readfn = aa64_uao_read, .writefn = aa64_uao_write
+};
+
 static CPAccessResult aa64_cacheop_access(CPUARMState *env,
                                           const ARMCPRegInfo *ri,
                                           bool isread)
@@ -7673,6 +7691,9 @@ void register_cp_regs_for_features(ARMCPU *cpu)
         define_arm_cp_regs(cpu, ats1cp_reginfo);
     }
 #endif
+    if (cpu_isar_feature(aa64_uao, cpu)) {
+        define_one_arm_cp_reg(cpu, &uao_reginfo);
+    }
 
     if (arm_feature(env, ARM_FEATURE_EL2) && cpu_isar_feature(aa64_vh, cpu)) {
         define_arm_cp_regs(cpu, vhe_reginfo);
diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index d8ba240a15..7c26c3bfeb 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -1602,6 +1602,20 @@ static void handle_msr_i(DisasContext *s, uint32_t insn,
         s->base.is_jmp = DISAS_NEXT;
         break;
 
+    case 0x03: /* UAO */
+        if (!dc_isar_feature(aa64_uao, s) || s->current_el == 0) {
+            goto do_unallocated;
+        }
+        if (crm & 1) {
+            set_pstate_bits(PSTATE_UAO);
+        } else {
+            clear_pstate_bits(PSTATE_UAO);
+        }
+        t1 = tcg_const_i32(s->current_el);
+        gen_helper_rebuild_hflags_a64(cpu_env, t1);
+        tcg_temp_free_i32(t1);
+        break;
+
     case 0x04: /* PAN */
         if (!dc_isar_feature(aa64_pan, s) || s->current_el == 0) {
             goto do_unallocated;
-- 
2.20.1