target/arm: Use field names for manipulating EL2 and EL3 modes

Use FIELD_DP{32,64} to manipulate id_pfr1 and id_aa64pfr0
during arm_cpu_realizefn.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220506180242.216785-11-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

target/arm/cpu.c

@@ -1793,11 +1793,13 @@ static void arm_cpu_realizefn(DeviceState *dev, Error **errp)
          */
         unset_feature(env, ARM_FEATURE_EL3);
 
-        /* Disable the security extension feature bits in the processor feature
-         * registers as well. These are id_pfr1[7:4] and id_aa64pfr0[15:12].
+        /*
+         * Disable the security extension feature bits in the processor
+         * feature registers as well.
          */
-        cpu->isar.id_pfr1 &= ~0xf0;
-        cpu->isar.id_aa64pfr0 &= ~0xf000;
+        cpu->isar.id_pfr1 = FIELD_DP32(cpu->isar.id_pfr1, ID_PFR1, SECURITY, 0);
+        cpu->isar.id_aa64pfr0 = FIELD_DP64(cpu->isar.id_aa64pfr0,
+                                           ID_AA64PFR0, EL3, 0);
     }
 
     if (!cpu->has_el2) {
@@ -1828,12 +1830,14 @@ static void arm_cpu_realizefn(DeviceState *dev, Error **errp)
     }
 
     if (!arm_feature(env, ARM_FEATURE_EL2)) {
-        /* Disable the hypervisor feature bits in the processor feature
-         * registers if we don't have EL2. These are id_pfr1[15:12] and
-         * id_aa64pfr0_el1[11:8].
+        /*
+         * Disable the hypervisor feature bits in the processor feature
+         * registers if we don't have EL2.
          */
-        cpu->isar.id_aa64pfr0 &= ~0xf00;
-        cpu->isar.id_pfr1 &= ~0xf000;
+        cpu->isar.id_aa64pfr0 = FIELD_DP64(cpu->isar.id_aa64pfr0,
+                                           ID_AA64PFR0, EL2, 0);
+        cpu->isar.id_pfr1 = FIELD_DP32(cpu->isar.id_pfr1,
+                                       ID_PFR1, VIRTUALIZATION, 0);
     }
 
 #ifndef CONFIG_USER_ONLY