target/arm: Honour HCR_EL2.TGE and MDCR_EL2.TDE in debug register access checks

Some debug registers can be trapped via MDCR_EL2 bits TDRA, TDOSA,
and TDA, which we implement in the functions access_tdra(),
access_tdosa() and access_tda(). If MDCR_EL2.TDE or HCR_EL2.TGE
are 1, the TDRA, TDOSA and TDA bits should behave as if they were 1.
Implement this by having the access functions check MDCR_EL2.TDE
and HCR_EL2.TGE.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180724115950.17316-3-peter.maydell@linaro.org

target/arm/helper.c

@@ -444,9 +444,11 @@ static CPAccessResult access_tdosa(CPUARMState *env, const ARMCPRegInfo *ri,
                                    bool isread)
 {
     int el = arm_current_el(env);
+    bool mdcr_el2_tdosa = (env->cp15.mdcr_el2 & MDCR_TDOSA) ||
+        (env->cp15.mdcr_el2 & MDCR_TDE) ||
+        (env->cp15.hcr_el2 & HCR_TGE);
 
-    if (el < 2 && (env->cp15.mdcr_el2 & MDCR_TDOSA)
-        && !arm_is_secure_below_el3(env)) {
+    if (el < 2 && mdcr_el2_tdosa && !arm_is_secure_below_el3(env)) {
         return CP_ACCESS_TRAP_EL2;
     }
     if (el < 3 && (env->cp15.mdcr_el3 & MDCR_TDOSA)) {
@@ -462,9 +464,11 @@ static CPAccessResult access_tdra(CPUARMState *env, const ARMCPRegInfo *ri,
                                   bool isread)
 {
     int el = arm_current_el(env);
+    bool mdcr_el2_tdra = (env->cp15.mdcr_el2 & MDCR_TDRA) ||
+        (env->cp15.mdcr_el2 & MDCR_TDE) ||
+        (env->cp15.hcr_el2 & HCR_TGE);
 
-    if (el < 2 && (env->cp15.mdcr_el2 & MDCR_TDRA)
-        && !arm_is_secure_below_el3(env)) {
+    if (el < 2 && mdcr_el2_tdra && !arm_is_secure_below_el3(env)) {
         return CP_ACCESS_TRAP_EL2;
     }
     if (el < 3 && (env->cp15.mdcr_el3 & MDCR_TDA)) {
@@ -480,9 +484,11 @@ static CPAccessResult access_tda(CPUARMState *env, const ARMCPRegInfo *ri,
                                   bool isread)
 {
     int el = arm_current_el(env);
+    bool mdcr_el2_tda = (env->cp15.mdcr_el2 & MDCR_TDA) ||
+        (env->cp15.mdcr_el2 & MDCR_TDE) ||
+        (env->cp15.hcr_el2 & HCR_TGE);
 
-    if (el < 2 && (env->cp15.mdcr_el2 & MDCR_TDA)
-        && !arm_is_secure_below_el3(env)) {
+    if (el < 2 && mdcr_el2_tda && !arm_is_secure_below_el3(env)) {
         return CP_ACCESS_TRAP_EL2;
     }
     if (el < 3 && (env->cp15.mdcr_el3 & MDCR_TDA)) {