target/arm: Introduce arm_hcr_el2_eff_secstate

For page walking, we may require HCR for a security state
that is not "current".

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20221001162318.153420-14-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

2 files changed, 21 insertions, 10 deletions

diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index 53f4c23..d541392 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -2412,15 +2412,15 @@ static inline bool arm_is_secure(CPUARMState *env)
  * Return true if the current security state has AArch64 EL2 or AArch32 Hyp.
  * This corresponds to the pseudocode EL2Enabled()
  */
+static inline bool arm_is_el2_enabled_secstate(CPUARMState *env, bool secure)
+{
+    return arm_feature(env, ARM_FEATURE_EL2)
+           && (!secure || (env->cp15.scr_el3 & SCR_EEL2));
+}
+
 static inline bool arm_is_el2_enabled(CPUARMState *env)
 {
-    if (arm_feature(env, ARM_FEATURE_EL2)) {
-        if (arm_is_secure_below_el3(env)) {
-            return (env->cp15.scr_el3 & SCR_EEL2) != 0;
-        }
-        return true;
-    }
-    return false;
+    return arm_is_el2_enabled_secstate(env, arm_is_secure_below_el3(env));
 }
 
 #else
@@ -2434,6 +2434,11 @@ static inline bool arm_is_secure(CPUARMState *env)
     return false;
 }
 
+static inline bool arm_is_el2_enabled_secstate(CPUARMState *env, bool secure)
+{
+    return false;
+}
+
 static inline bool arm_is_el2_enabled(CPUARMState *env)
 {
     return false;
@@ -2446,6 +2451,7 @@ static inline bool arm_is_el2_enabled(CPUARMState *env)
  * "for all purposes other than a direct read or write access of HCR_EL2."
  * Not included here is HCR_RW.
  */
+uint64_t arm_hcr_el2_eff_secstate(CPUARMState *env, bool secure);
 uint64_t arm_hcr_el2_eff(CPUARMState *env);
 uint64_t arm_hcrx_el2_eff(CPUARMState *env);
 
diff --git a/target/arm/helper.c b/target/arm/helper.c
index b1b8725..f1266bb 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -5229,15 +5229,15 @@ static void hcr_writelow(CPUARMState *env, const ARMCPRegInfo *ri,
 }
 
 /*
- * Return the effective value of HCR_EL2.
+ * Return the effective value of HCR_EL2, at the given security state.
  * Bits that are not included here:
  * RW       (read from SCR_EL3.RW as needed)
  */
-uint64_t arm_hcr_el2_eff(CPUARMState *env)
+uint64_t arm_hcr_el2_eff_secstate(CPUARMState *env, bool secure)
 {
     uint64_t ret = env->cp15.hcr_el2;
 
-    if (!arm_is_el2_enabled(env)) {
+    if (!arm_is_el2_enabled_secstate(env, secure)) {
         /*
          * "This register has no effect if EL2 is not enabled in the
          * current Security state".  This is ARMv8.4-SecEL2 speak for
@@ -5296,6 +5296,11 @@ uint64_t arm_hcr_el2_eff(CPUARMState *env)
     return ret;
 }
 
+uint64_t arm_hcr_el2_eff(CPUARMState *env)
+{
+    return arm_hcr_el2_eff_secstate(env, arm_is_secure_below_el3(env));
+}
+
 /*
  * Corresponds to ARM pseudocode function ELIsInHost().
  */