[Qemu-devel] [PATCH v4 06/21] target-arm: Provide syndrome information for MMU faults

[Peter Maydell]

From: Rob Herring <address@hidden>

Set up the required syndrome information when we detect an MMU fault.

Signed-off-by: Rob Herring <address@hidden>
[PMM: split out from exception handling patch, tweaked to bring
 in line with how we create other kinds of syndrome information]
Signed-off-by: Peter Maydell <address@hidden>
---
 target-arm/helper.c    | 16 ++++++++++++++++
 target-arm/internals.h | 13 +++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/target-arm/helper.c b/target-arm/helper.c
index 2fa01ae..d547a9d 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -3586,6 +3586,7 @@ int cpu_arm_handle_mmu_fault (CPUARMState *env, 
target_ulong address,
     target_ulong page_size;
     int prot;
     int ret, is_user;
+    uint32_t syn;
 
     is_user = mmu_idx == MMU_USER_IDX;
     ret = get_phys_addr(env, address, access_type, is_user, &phys_addr, &prot,
@@ -3598,14 +3599,29 @@ int cpu_arm_handle_mmu_fault (CPUARMState *env, 
target_ulong address,
         return 0;
     }
 
+    /* AArch64 syndrome does not have an LPAE bit */
+    syn = ret & ~(1 << 9);
+
+    /* For insn and data aborts we assume there is no instruction syndrome
+     * information; this is always true for exceptions reported to EL1.
+     */
     if (access_type == 2) {
+        syn = syn_insn_abort(0, 0, syn);
         env->exception_index = EXCP_PREFETCH_ABORT;
     } else {
+        syn = syn_data_abort(0, 0, 0, access_type == 1, syn);
         if (access_type == 1 && arm_feature(env, ARM_FEATURE_V6)) {
             ret |= (1 << 11);
         }
         env->exception_index = EXCP_DATA_ABORT;
     }
+
+    /* Set bit 26 for exceptions with no change in EL */
+    if (arm_current_pl(env)) {
+        syn |= 1 << ARM_EL_EC_SHIFT;
+    }
+
+    env->exception.syndrome = syn;
     env->exception.vaddress = address;
     env->exception.fsr = ret;
     return 1;
diff --git a/target-arm/internals.h b/target-arm/internals.h
index 9bec4e1..93f56a5 100644
--- a/target-arm/internals.h
+++ b/target-arm/internals.h
@@ -188,4 +188,17 @@ static inline uint32_t syn_cp15_rrt_trap(int cv, int cond, 
int opc1, int crm,
         | (rt2 << 10) | (rt << 5) | (crm << 1) | isread;
 }
 
+static inline uint32_t syn_insn_abort(int ea, int s1ptw, int fsc)
+{
+    return (EC_INSNABORT << ARM_EL_EC_SHIFT) | (ea << 9)
+        | (s1ptw << 7) | fsc;
+}
+
+static inline uint32_t syn_data_abort(int ea, int cm, int s1ptw, int wnr,
+                                      int fsc)
+{
+    return (EC_DATAABORT << ARM_EL_EC_SHIFT) | (ea << 9)
+        | (cm << 8) | (s1ptw << 7) | (wnr << 6) | fsc;
+}
+
 #endif
-- 
1.9.0