diff --git a/sim/bfin/ChangeLog b/sim/bfin/ChangeLog
index 4445006..ac4b774 100644
--- a/sim/bfin/ChangeLog
+++ b/sim/bfin/ChangeLog
@@ -1,3 +1,7 @@
+2015-11-17  Mike Frysinger  <vapier@gentoo.org>
+
+	* tconfig.h (WITH_MODULO_MEMORY): Delete.
+
 2015-11-15  Mike Frysinger  <vapier@gentoo.org>
 
 	* Makefile.in (SIM_OBJS): Delete sim-reason.o, sim-reg.o, and
diff --git a/sim/bfin/tconfig.h b/sim/bfin/tconfig.h
index d28fd8d..a3e6f7b 100644
--- a/sim/bfin/tconfig.h
+++ b/sim/bfin/tconfig.h
@@ -9,7 +9,3 @@
 
 /* ??? Temporary hack until model support unified.  */
 #define SIM_HAVE_MODEL
-
-/* Allows us to do the memory aliasing that some bfroms have:
-   {0xef000000 - 0xef100000} => {0xef000000 - 0xef000800}  */
-#define WITH_MODULO_MEMORY 1
diff --git a/sim/common/ChangeLog b/sim/common/ChangeLog
index 7c0ef37..ddf4558 100644
--- a/sim/common/ChangeLog
+++ b/sim/common/ChangeLog
@@ -1,3 +1,11 @@
+2015-11-17  Mike Frysinger  <vapier@gentoo.org>
+
+	* sim-main.h (WITH_MODULO_MEMORY): Delete.
+	* sim-core.c (new_sim_core_mapping): Always assign mask to modulo-1.
+	(sim_core_attach): Delete WITH_MODULO_MEMORY == 0 logic.
+	(sim_core_translate): Likewise.
+	* sim-core.h: Delete mention of WITH_MODULO_MEMORY.
+
 2015-11-16  Mike Frysinger  <vapier@gentoo.org>
 
 	* sim-close.c (__cgen_cpu_close, _cgen_cpu_close): Delete.
diff --git a/sim/common/sim-config.h b/sim/common/sim-config.h
index f4fe076..d34ae88 100644
--- a/sim/common/sim-config.h
+++ b/sim/common/sim-config.h
@@ -398,10 +398,6 @@ extern char *simulator_sysroot;
 #define WITH_CALLBACK_MEMORY		1
 #endif
 
-#ifndef WITH_MODULO_MEMORY
-#define WITH_MODULO_MEMORY              0
-#endif
-
 
 
 /* Alignment:
diff --git a/sim/common/sim-core.c b/sim/common/sim-core.c
index 43e9076..724a036 100644
--- a/sim/common/sim-core.c
+++ b/sim/common/sim-core.c
@@ -157,10 +157,7 @@ new_sim_core_mapping (SIM_DESC sd,
   new_mapping->base = addr;
   new_mapping->nr_bytes = nr_bytes;
   new_mapping->bound = addr + (nr_bytes - 1);
-  if (modulo == 0)
-    new_mapping->mask = (unsigned) 0 - 1;
-  else
-    new_mapping->mask = modulo - 1;
+  new_mapping->mask = modulo - 1;
   new_mapping->buffer = buffer;
   new_mapping->free_buffer = free_buffer;
   new_mapping->device = device;
@@ -298,17 +295,6 @@ sim_core_attach (SIM_DESC sd,
   if (cpu != NULL)
     sim_io_error (sd, "sim_core_map_attach - processor specific memory map not yet supported");
 
-  /* verify modulo memory */
-  if (!WITH_MODULO_MEMORY && modulo != 0)
-    {
-#if (WITH_DEVICES)
-      device_error (client, "sim_core_attach - internal error - modulo memory disabled");
-#endif
-#if (WITH_HW)
-      sim_hw_abort (sd, client, "sim_core_attach - internal error - modulo memory disabled");
-#endif
-      sim_io_error (sd, "sim_core_attach - internal error - modulo memory disabled");
-    }
   if (client != NULL && modulo != 0)
     {
 #if (WITH_DEVICES)
@@ -497,12 +483,8 @@ STATIC_INLINE_SIM_CORE\
 sim_core_translate (sim_core_mapping *mapping,
 		    address_word addr)
 {
-  if (WITH_MODULO_MEMORY)
-    return (void *)((unsigned8 *) mapping->buffer
-		    + ((addr - mapping->base) & mapping->mask));
-  else
-    return (void *)((unsigned8 *) mapping->buffer
-		    + addr - mapping->base);
+  return (void *)((unsigned8 *) mapping->buffer
+		  + ((addr - mapping->base) & mapping->mask));
 }
 
 
diff --git a/sim/common/sim-core.h b/sim/common/sim-core.h
index 64d2508..a60e60a 100644
--- a/sim/common/sim-core.h
+++ b/sim/common/sim-core.h
@@ -119,10 +119,9 @@ extern SIM_RC sim_core_install (SIM_DESC sd);
    translated into ADDRESS_SPACE:OFFSET before being passed to the
    client device.
 
-   MODULO - when the simulator has been configured WITH_MODULO support
-   and is greater than zero, specifies that accesses to the region
-   [ADDR .. ADDR+NR_BYTES) should be mapped onto the sub region [ADDR
-   .. ADDR+MODULO).  The modulo value must be a power of two.
+   MODULO - Specifies that accesses to the region [ADDR .. ADDR+NR_BYTES)
+   should be mapped onto the sub region [ADDR .. ADDR+MODULO).  The modulo
+   value must be a power of two.
 
    DEVICE - When non NULL, indicates that this is a callback memory
    space and specified device's memory callback handler should be
diff --git a/sim/m68hc11/ChangeLog b/sim/m68hc11/ChangeLog
index 1f8d0cf..8e2d1a5 100644
--- a/sim/m68hc11/ChangeLog
+++ b/sim/m68hc11/ChangeLog
@@ -1,3 +1,7 @@
+2015-11-17  Mike Frysinger  <vapier@gentoo.org>
+
+	* sim-main.h (WITH_MODULO_MEMORY): Delete.
+
 2015-11-15  Mike Frysinger  <vapier@gentoo.org>
 
 	* Makefile.in (SIM_OBJS): Delete sim-reason.o and sim-stop.o.
diff --git a/sim/m68hc11/sim-main.h b/sim/m68hc11/sim-main.h
index d1fc582..be33b48 100644
--- a/sim/m68hc11/sim-main.h
+++ b/sim/m68hc11/sim-main.h
@@ -20,7 +20,6 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 #ifndef _SIM_MAIN_H
 #define _SIM_MAIN_H
 
-#define WITH_MODULO_MEMORY 1
 #define WITH_WATCHPOINTS 1
 #define SIM_HANDLES_LMA 1
 
diff --git a/sim/mips/ChangeLog b/sim/mips/ChangeLog
index 706b0fc..d37ab7a 100644
--- a/sim/mips/ChangeLog
+++ b/sim/mips/ChangeLog
@@ -1,3 +1,7 @@
+2015-11-17  Mike Frysinger  <vapier@gentoo.org>
+
+	* sim-main.h (WITH_MODULO_MEMORY): Delete.
+
 2015-11-15  Mike Frysinger  <vapier@gentoo.org>
 
 	* Makefile.in (SIM_OBJS): Delete sim-reason.o and sim-stop.o.
diff --git a/sim/mips/sim-main.h b/sim/mips/sim-main.h
index adf60c7..bb64dcb 100644
--- a/sim/mips/sim-main.h
+++ b/sim/mips/sim-main.h
@@ -22,7 +22,6 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 /* hobble some common features for moment */
 #define WITH_WATCHPOINTS 1
-#define WITH_MODULO_MEMORY 1
 
 
 #define SIM_CORE_SIGNAL(SD,CPU,CIA,MAP,NR_BYTES,ADDR,TRANSFER,ERROR) \
diff --git a/sim/v850/ChangeLog b/sim/v850/ChangeLog
index 6e94282..7efd9d1 100644
--- a/sim/v850/ChangeLog
+++ b/sim/v850/ChangeLog
@@ -1,3 +1,7 @@
+2015-11-17  Mike Frysinger  <vapier@gentoo.org>
+
+	* sim-main.h (WITH_MODULO_MEMORY): Delete.
+
 2015-11-15  Mike Frysinger  <vapier@gentoo.org>
 
 	* Makefile.in (SIM_OBJS): Delete sim-reason.o and sim-stop.o.
diff --git a/sim/v850/sim-main.h b/sim/v850/sim-main.h
index 5127d28..0c041ba 100644
--- a/sim/v850/sim-main.h
+++ b/sim/v850/sim-main.h
@@ -4,7 +4,6 @@
 /* General config options */
 
 #define WITH_CORE
-#define WITH_MODULO_MEMORY 1
 #define WITH_WATCHPOINTS 1
 
 
