diff --git a/sys/powerpc/wii/platform_wii.c b/sys/powerpc/wii/platform_wii.c
index 78784ed1dc4..dcf1fc019a8 100644
--- a/sys/powerpc/wii/platform_wii.c
+++ b/sys/powerpc/wii/platform_wii.c
@@ -50,6 +50,7 @@ __FBSDID("$FreeBSD$");
 #include <machine/vmparam.h>
 
 #include <powerpc/wii/wii_fbreg.h>
+#include <powerpc/wii/wii_ipcreg.h>
 
 #include "platform_if.h"
 
@@ -113,7 +114,7 @@ wii_mem_regions(platform_t plat, struct mem_region **phys, int *physsz,
 {
 	/* 24MB 1T-SRAM */
 	avail_regions[0].mr_start = 0x00000000;
-	avail_regions[0].mr_size  = 0x01800000 - 0x0004000;
+	avail_regions[0].mr_size  = 0x01800000;
 
 	/*
 	 * Reserve space for the framebuffer which is located
@@ -122,12 +123,19 @@ wii_mem_regions(platform_t plat, struct mem_region **phys, int *physsz,
 	avail_regions[0].mr_size -= WIIFB_FB_LEN;
 
 	/* 64MB GDDR3 SDRAM */
-	avail_regions[1].mr_start = 0x10000000 + 0x0004000;
-	avail_regions[1].mr_size  = 0x04000000 - 0x0004000;
+	avail_regions[1].mr_start = 0x10000000;
+	avail_regions[1].mr_size  = 0x04000000;
 
-	/* XXX for now only use the first memory region */
-#undef MEM_REGIONS
-#define MEM_REGIONS 1
+	/*
+	 * Reserve space for the DSP.
+	 */
+	avail_regions[1].mr_start += 0x4000;
+	avail_regions[1].mr_size -= 0x4000;
+
+	/*
+	 * Reserve space for the IOS I/O memory.
+	 */
+	avail_regions[1].mr_size -= WIIIPC_IOH_LEN + 1;
 
 	*phys = *avail = avail_regions;
 	*physsz = *availsz = MEM_REGIONS;