+2015-12-26  Mike Frysinger  <vapier@gentoo.org>
+
+       * sim-core.c (sim_core_read_buffer): Move cia decl to top of func.
+       Call sim_cpu_hw_io_read_buffer if cpu is valid.
+       (sim_core_write_buffer): Move cia decl to top of func.  Call
+       sim_cpu_hw_io_write_buffer if cpu is valid.
+
 2015-12-25  Mike Frysinger  <vapier@gentoo.org>
 
        * hw-properties.c (hw_find_ihandle_runtime_property): Delete
 
        int nr_bytes = len - count;
        if (raddr + nr_bytes - 1> mapping->bound)
          nr_bytes = mapping->bound - raddr + 1;
-       if (sim_hw_io_read_buffer (sd, mapping->device,
-                                  (unsigned_1*)buffer + count,
-                                  mapping->space,
-                                  raddr,
-                                  nr_bytes) != nr_bytes)
+       /* If the access was initiated by a cpu, pass it down so errors can
+          be propagated properly.  For other sources (e.g. GDB or DMA), we
+          can only signal errors via the return value.  */
+       if (cpu)
+         {
+           sim_cia cia = cpu ? CPU_PC_GET (cpu) : NULL_CIA;
+           sim_cpu_hw_io_read_buffer (cpu, cia, mapping->device,
+                                      (unsigned_1*)buffer + count,
+                                      mapping->space,
+                                      raddr,
+                                      nr_bytes);
+         }
+       else if (sim_hw_io_read_buffer (sd, mapping->device,
+                                       (unsigned_1*)buffer + count,
+                                       mapping->space,
+                                       raddr,
+                                       nr_bytes) != nr_bytes)
          break;
        count += nr_bytes;
        continue;
          int nr_bytes = len - count;
          if (raddr + nr_bytes - 1 > mapping->bound)
            nr_bytes = mapping->bound - raddr + 1;
-         if (sim_hw_io_write_buffer (sd, mapping->device,
-                                     (unsigned_1*)buffer + count,
-                                     mapping->space,
-                                     raddr,
-                                     nr_bytes) != nr_bytes)
+         /* If the access was initiated by a cpu, pass it down so errors can
+            be propagated properly.  For other sources (e.g. GDB or DMA), we
+            can only signal errors via the return value.  */
+         if (cpu)
+           {
+             sim_cia cia = cpu ? CPU_PC_GET (cpu) : NULL_CIA;
+             sim_cpu_hw_io_write_buffer (cpu, cia, mapping->device,
+                                         (unsigned_1*)buffer + count,
+                                         mapping->space,
+                                         raddr,
+                                         nr_bytes);
+           }
+         else if (sim_hw_io_write_buffer (sd, mapping->device,
+                                         (unsigned_1*)buffer + count,
+                                         mapping->space,
+                                         raddr,
+                                         nr_bytes) != nr_bytes)
            break;
          count += nr_bytes;
          continue;