diff --git a/exosphere/src/mc0.h b/exosphere/src/mc0.h
new file mode 100644
index 000000000..8e4f51848
--- /dev/null
+++ b/exosphere/src/mc0.h
@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2018-2020 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef EXOSPHERE_MC0_H
+#define EXOSPHERE_MC0_H
+
+#include <stdint.h>
+#include "memory_map.h"
+
+/* Exosphere driver for the Tegra X1 MC0. */
+
+static inline uintptr_t get_mc0_base(void) {
+    return MMIO_GET_DEVICE_ADDRESS(MMIO_DEVID_MC0);
+}
+
+#define MC0_BASE  (get_mc0_base())
+#define MAKE_MC0_REG(n) MAKE_REG32(MC0_BASE + n)
+
+#endif
diff --git a/exosphere/src/mc1.h b/exosphere/src/mc1.h
new file mode 100644
index 000000000..bcdfe03be
--- /dev/null
+++ b/exosphere/src/mc1.h
@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2018-2020 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef EXOSPHERE_MC0_H
+#define EXOSPHERE_MC0_H
+
+#include <stdint.h>
+#include "memory_map.h"
+
+/* Exosphere driver for the Tegra X1 MC1. */
+
+static inline uintptr_t get_mc1_base(void) {
+    return MMIO_GET_DEVICE_ADDRESS(MMIO_DEVID_MC1);
+}
+
+#define MC1_BASE  (get_mc1_base())
+#define MAKE_MC1_REG(n) MAKE_REG32(MC1_BASE + n)
+
+#endif
diff --git a/exosphere/src/memory_map.h b/exosphere/src/memory_map.h
index 81c378eb1..aca65bf69 100644
--- a/exosphere/src/memory_map.h
+++ b/exosphere/src/memory_map.h
@@ -13,7 +13,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
- 
+
 #ifndef EXOSPHERE_MEMORY_MAP_H
 #define EXOSPHERE_MEMORY_MAP_H
 
@@ -48,9 +48,11 @@
 #define _MMAPDEV15      ( 0x6000D000ull, 0x1000ull, true  ) /* GPIO-1 - GPIO-8 */
 #define _MMAPDEV16      ( 0x7000C000ull, 0x1000ull, true  ) /* I2C-I2C4 */
 #define _MMAPDEV17      ( 0x6000F000ull, 0x1000ull, true  ) /* Exception vectors */
-#define _MMAPDEV18      ( 0x00000000ull, 0x1000ull, true  ) /* AMS irampage, NOT mapped at startup */
-#define _MMAPDEV19      ( 0x00000000ull, 0x1000ull, true  ) /* AMS userpage, NOT mapped at startup */
-#define _MMAPDEV20      ( 0x40038000ull, 0x5000ull, true  ) /* DEBUG: IRAM */
+#define _MMAPDEV18      ( 0x7001C000ull, 0x1000ull, true  ) /* MC0 */
+#define _MMAPDEV19      ( 0x7001D000ull, 0x1000ull, true  ) /* MC1 */
+#define _MMAPDEV20      ( 0x00000000ull, 0x1000ull, true  ) /* AMS irampage, NOT mapped at startup */
+#define _MMAPDEV21      ( 0x00000000ull, 0x1000ull, true  ) /* AMS userpage, NOT mapped at startup */
+#define _MMAPDEV22      ( 0x40038000ull, 0x1000ull, true  ) /* DEBUG: IRAM */
 
 /* MMIO 7.0.0+. (addr).  */
 #define _MMAPDEV7X0       ( 0x50041000ull ) /* ARM Interrupt Distributor */
@@ -71,9 +73,11 @@
 #define _MMAPDEV7X15      ( 0x6000D000ull ) /* GPIO-1 - GPIO-8 */
 #define _MMAPDEV7X16      ( 0x7000C000ull ) /* I2C-I2C4 */
 #define _MMAPDEV7X17      ( 0x6000F000ull ) /* Exception vectors */
-#define _MMAPDEV7X18      ( 0x00000000ull ) /* AMS irampage, NOT mapped at startup */
-#define _MMAPDEV7X19      ( 0x00000000ull ) /* AMS userpage, NOT mapped at startup */
-#define _MMAPDEV7X20      ( 0x40038000ull ) /* DEBUG: IRAM */
+#define _MMAPDEV7X18      ( 0x7001C000ull ) /* MC0 */
+#define _MMAPDEV7X19      ( 0x7001D000ull ) /* MC1 */
+#define _MMAPDEV7X20      ( 0x00000000ull ) /* AMS irampage, NOT mapped at startup */
+#define _MMAPDEV7X21      ( 0x00000000ull ) /* AMS userpage, NOT mapped at startup */
+#define _MMAPDEV7X22      ( 0x40038000ull ) /* DEBUG: IRAM */
 
 /* LP0 entry ram segments (addr, size, additional attributes) */
 #define _MMAPLP0ES0  ( 0x40020000ull, 0x10000ull, MMU_PTE_BLOCK_NS | ATTRIB_MEMTYPE_DEVICE ) /* Encrypted TZRAM */
@@ -133,10 +137,12 @@
 #define MMIO_DEVID_GPIO                 15
 #define MMIO_DEVID_DTV_I2C234           16
 #define MMIO_DEVID_EXCEPTION_VECTORS    17
-#define MMIO_DEVID_AMS_IRAM_PAGE        18
-#define MMIO_DEVID_AMS_USER_PAGE        19
-#define MMIO_DEVID_DEBUG_IRAM           20
-#define MMIO_DEVID_MAX                  21
+#define MMIO_DEVID_MC0                  18
+#define MMIO_DEVID_MC1                  19
+#define MMIO_DEVID_AMS_IRAM_PAGE        20
+#define MMIO_DEVID_AMS_USER_PAGE        21
+#define MMIO_DEVID_DEBUG_IRAM           22
+#define MMIO_DEVID_MAX                  23
 
 #define LP0_ENTRY_RAM_SEGMENT_ID_ENCRYPTED_TZRAM    0
 #define LP0_ENTRY_RAM_SEGMENT_ID_LP0_ENTRY_CODE     1
diff --git a/exosphere/src/smc_api.c b/exosphere/src/smc_api.c
index 499928451..2338102ac 100644
--- a/exosphere/src/smc_api.c
+++ b/exosphere/src/smc_api.c
@@ -25,6 +25,8 @@
 #include "synchronization.h"
 #include "masterkey.h"
 #include "mc.h"
+#include "mc0.h"
+#include "mc1.h"
 #include "memory_map.h"
 #include "pmc.h"
 #include "randomcache.h"
@@ -617,7 +619,7 @@ uint32_t smc_read_write_register(smc_args_t *args) {
     }
     /* Check for PMC registers. */
     if (0x7000E400 <= address && address <= 0x7000EFFF) {
-        const uint8_t pmc_whitelist[0x28] = {
+        static const uint8_t pmc_whitelist[0x28] = {
             0xB9, 0xF9, 0x07, 0x00, 0x00, 0x00, 0x80, 0x03,
             0x00, 0x00, 0x00, 0x17, 0x00, 0xC4, 0x07, 0x00,
             0x00, 0x00, 0x00, 0x00, 0x00, 0x20, 0x20, 0x00,
@@ -633,39 +635,83 @@ uint32_t smc_read_write_register(smc_args_t *args) {
         } else {
             return 2;
         }
-    } else if (exosphere_get_target_firmware() >= ATMOSPHERE_TARGET_FIRMWARE_400 && MMIO_GET_DEVICE_PA(MMIO_DEVID_MC) <= address &&
-               address < MMIO_GET_DEVICE_PA(MMIO_DEVID_MC) + MMIO_GET_DEVICE_SIZE(MMIO_DEVID_MC)) {
-        /* Memory Controller RW supported only on 4.0.0+ */
-        const uint8_t mc_whitelist[0x68] = {
-            0x9F, 0x31, 0x30, 0x00, 0xF0, 0xFF, 0xF7, 0x01,
-            0xCD, 0xFE, 0xC0, 0xFE, 0x00, 0x00, 0x00, 0x00,
-            0x03, 0x40, 0x73, 0x3E, 0x2F, 0x00, 0x00, 0x6E,
-            0x30, 0x05, 0x06, 0xB0, 0x71, 0xC8, 0x43, 0x04,
-            0x80, 0x1F, 0x08, 0x80, 0x03, 0x00, 0x0E, 0x00,
-            0x08, 0x00, 0xE0, 0x00, 0x0E, 0x00, 0x00, 0x00,
-            0x00, 0x00, 0x00, 0x30, 0xF0, 0x03, 0x03, 0x30,
-            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-            0x00, 0x00, 0x00, 0x31, 0x00, 0x40, 0x00, 0x00,
-            0x00, 0x03, 0x00, 0x00, 0xE4, 0xFF, 0xFF, 0x01,
-            0x00, 0x00, 0x00, 0x00, 0x0C, 0x00, 0xFE, 0x0F,
-            0x01, 0x00, 0x80, 0x00, 0x00, 0x08, 0x00, 0x00
-        };
-        uint32_t offset = (uint32_t)(address - 0x70019000);
-        uint32_t wl_ind = (offset >> 5);
-        /* If address is whitelisted, allow write. */
-        if (wl_ind < sizeof(mc_whitelist) && (mc_whitelist[wl_ind] & (1 << ((offset >> 2) & 0x7)))) {
-            p_mmio = (volatile uint32_t *)(MMIO_GET_DEVICE_ADDRESS(MMIO_DEVID_MC) + offset);
-        } else {
-            /* These addresses are not allowed by the whitelist. */
-            /* They correspond to SMMU DISABLE for the BPMP, and for APB-DMA. */
-            /* However, smcReadWriteRegister returns 0 for these addresses despite not actually performing the write. */
-            /* This is "probably" to fuck with hackers who got access to smcReadWriteRegister and are trying to get */
-            /* control of the BPMP for jamais vu etc., since there's no other reason to return 0 despite failure. */
-            if (address == 0x7001923C || address == 0x70019298) {
-                return 0;
+    } else {
+        if (exosphere_get_target_firmware() >= ATMOSPHERE_TARGET_FIRMWARE_500) {
+            static const uint8_t mc_whitelist_5x[0xD00/(sizeof(uint32_t) * 8)] = {
+                0x9F, 0x31, 0x30, 0x00, 0xF0, 0xFF, 0xF7, 0x01,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x03, 0x40, 0x73, 0x3E, 0x2F, 0x00, 0x00, 0x6E,
+                0x30, 0x05, 0x06, 0xB0, 0x71, 0xC8, 0x43, 0x04,
+                0x80, 0xFF, 0x08, 0x80, 0x03, 0x38, 0x8E, 0x1F,
+                0xC8, 0xFF, 0xFF, 0x00, 0x0E, 0x00, 0x00, 0x00,
+                0xF0, 0x1F, 0x00, 0x30, 0xF0, 0x03, 0x03, 0x30,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x31, 0x00, 0x40, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0xE4, 0xFF, 0xFF, 0x01,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF8, 0x0F,
+                0x01, 0x00, 0x80, 0x00, 0x00, 0x08, 0x00, 0x00
+            };
+            static const uint8_t mc01_whitelist_5x[0xC00/(sizeof(uint32_t) * 8)] = {
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0xCD, 0xFE, 0xC0, 0xFE, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x0C, 0x00, 0x06, 0x00,
+            };
+            static const struct {
+                uint32_t phys_addr;
+                uint32_t size;
+                uint64_t virt_addr;
+                const uint8_t *whitelist;
+            } register_whitelists[3] = {
+                { MMIO_GET_DEVICE_PA(MMIO_DEVID_MC),  sizeof(mc_whitelist_5x)   * (sizeof(uint32_t) * 8), MMIO_GET_DEVICE_ADDRESS(MMIO_DEVID_MC),    mc_whitelist_5x },
+                { MMIO_GET_DEVICE_PA(MMIO_DEVID_MC0), sizeof(mc01_whitelist_5x) * (sizeof(uint32_t) * 8), MMIO_GET_DEVICE_ADDRESS(MMIO_DEVID_MC0), mc01_whitelist_5x },
+                { MMIO_GET_DEVICE_PA(MMIO_DEVID_MC1), sizeof(mc01_whitelist_5x) * (sizeof(uint32_t) * 8), MMIO_GET_DEVICE_ADDRESS(MMIO_DEVID_MC1), mc01_whitelist_5x },
+            };
+            for (unsigned int which = 0; which < 3; which++) {
+                if (register_whitelists[which].phys_addr <= address && address < register_whitelists[which].phys_addr + register_whitelists[which].size) {
+                    uint32_t offset = (uint32_t)(address - register_whitelists[which].phys_addr);
+                    uint32_t wl_ind = (offset >> 5);
+                    /* If address is whitelisted, allow write. */
+                    if (register_whitelists[which].whitelist[wl_ind] & (1 << ((offset >> 2) & 0x7))) {
+                        p_mmio = (volatile uint32_t *)(register_whitelists[which].virt_addr + offset);
+                    }
+                    break;
+                }
+            }
+        } else if (exosphere_get_target_firmware() >= ATMOSPHERE_TARGET_FIRMWARE_400) {
+            if (MMIO_GET_DEVICE_PA(MMIO_DEVID_MC) <= address && address < MMIO_GET_DEVICE_PA(MMIO_DEVID_MC) + 0xD00) {
+                /* Memory Controller RW supported only on 4.0.0+ */
+                static const uint8_t mc_whitelist[0x68] = {
+                    0x9F, 0x31, 0x30, 0x00, 0xF0, 0xFF, 0xF7, 0x01,
+                    0xCD, 0xFE, 0xC0, 0xFE, 0x00, 0x00, 0x00, 0x00,
+                    0x03, 0x40, 0x73, 0x3E, 0x2F, 0x00, 0x00, 0x6E,
+                    0x30, 0x05, 0x06, 0xB0, 0x71, 0xC8, 0x43, 0x04,
+                    0x80, 0x1F, 0x08, 0x80, 0x03, 0x00, 0x0E, 0x00,
+                    0x08, 0x00, 0xE0, 0x00, 0x0E, 0x00, 0x00, 0x00,
+                    0x00, 0x00, 0x00, 0x30, 0xF0, 0x03, 0x03, 0x30,
+                    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                    0x00, 0x00, 0x00, 0x31, 0x00, 0x40, 0x00, 0x00,
+                    0x00, 0x03, 0x00, 0x00, 0xE4, 0xFF, 0xFF, 0x01,
+                    0x00, 0x00, 0x00, 0x00, 0x0C, 0x00, 0xFE, 0x0F,
+                    0x01, 0x00, 0x80, 0x00, 0x00, 0x08, 0x00, 0x00
+                };
+                uint32_t offset = (uint32_t)(address - MMIO_GET_DEVICE_PA(MMIO_DEVID_MC));
+                uint32_t wl_ind = (offset >> 5);
+                /* If address is whitelisted, allow write. */
+                if (mc_whitelist[wl_ind] & (1 << ((offset >> 2) & 0x7))) {
+                    p_mmio = (volatile uint32_t *)(MMIO_GET_DEVICE_ADDRESS(MMIO_DEVID_MC) + offset);
+                }
             }
-            return 2;
         }
     }
 
@@ -684,9 +730,16 @@ uint32_t smc_read_write_register(smc_args_t *args) {
         /* Return old value. */
         args->X[1] = old_value;
         return 0;
+    } else if (exosphere_get_target_firmware() >= ATMOSPHERE_TARGET_FIRMWARE_400 && (address == 0x7001923C || address == 0x70019298)) {
+        /* These addresses are not allowed by the whitelist. */
+        /* They correspond to SMMU DISABLE for the BPMP, and for APB-DMA. */
+        /* However, smcReadWriteRegister returns 0 for these addresses despite not actually performing the write. */
+        /* This is "probably" to fuck with hackers who got access to smcReadWriteRegister and are trying to get */
+        /* control of the BPMP for jamais vu etc., since there's no other reason to return 0 despite failure. */
+        return 0;
+    } else {
+        return 2;
     }
-
-    return 2;
 }