microblaze: Trap on unaligned data accesses.

Untested...

Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/target-microblaze/op_helper.c b/target-microblaze/op_helper.c
index 134d243..a5b3827 100644
--- a/target-microblaze/op_helper.c
+++ b/target-microblaze/op_helper.c
@@ -206,6 +206,33 @@ uint32_t helper_pcmpbf(uint32_t a, uint32_t b)
     return 0;
 }
 
+void helper_memalign(uint32_t addr, uint32_t dr, uint32_t wr, uint32_t size)
+{
+    uint32_t mask;
+
+    switch (size) {
+        case 4: mask = 3; break;
+        case 2: mask = 1; break;
+        default:
+        case 1: mask = 0; break;
+    }
+
+    if (addr & mask) {
+            qemu_log("unaligned access addr=%x size=%d, wr=%d\n",
+                     addr, size, wr);
+            if (!(env->sregs[SR_MSR] & MSR_EE)) {
+                return;
+            }
+
+            env->sregs[SR_ESR] = ESR_EC_UNALIGNED_DATA | (wr << 10) \
+                                 | (dr & 31) << 5;
+            if (size == 4) {
+                env->sregs[SR_ESR] |= 1 << 11;
+            }
+            helper_raise_exception(EXCP_HW_EXCP);
+    }
+}
+
 #if !defined(CONFIG_USER_ONLY)
 /* Writes/reads to the MMU's special regs end up here.  */
 uint32_t helper_mmu_read(uint32_t rn)