Enable writes to the TERR and TEA bits when RAS is enabled.
These bits are otherwise RES0.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/helper.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/target/arm/helper.c b/target/arm/helper.c
index 37c5e42bc0..b6faebf4a7 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -1755,6 +1755,9 @@ static void scr_write(CPUARMState *env, const ARMCPRegInfo *ri, uint64_t value)
         }
         valid_mask &= ~SCR_NET;
 
+        if (cpu_isar_feature(aa64_ras, cpu)) {
+            valid_mask |= SCR_TERR;
+        }
         if (cpu_isar_feature(aa64_lor, cpu)) {
             valid_mask |= SCR_TLOR;
         }
@@ -1769,6 +1772,9 @@ static void scr_write(CPUARMState *env, const ARMCPRegInfo *ri, uint64_t value)
         }
     } else {
         valid_mask &= ~(SCR_RW | SCR_ST);
+        if (cpu_isar_feature(aa32_ras, cpu)) {
+            valid_mask |= SCR_TERR;
+        }
     }
 
     if (!arm_feature(env, ARM_FEATURE_EL2)) {
@@ -5126,6 +5132,9 @@ static void do_hcr_write(CPUARMState *env, uint64_t value, uint64_t valid_mask)
         if (cpu_isar_feature(aa64_vh, cpu)) {
             valid_mask |= HCR_E2H;
         }
+        if (cpu_isar_feature(aa64_ras, cpu)) {
+            valid_mask |= HCR_TERR | HCR_TEA;
+        }
         if (cpu_isar_feature(aa64_lor, cpu)) {
             valid_mask |= HCR_TLOR;
         }
-- 
2.34.1