diff --git a/setup.c b/setup.c
index 0ab33badb69..d0853db691b 100644
--- a/setup.c
+++ b/setup.c
@@ -196,9 +196,13 @@ void mpu_config(void)
 	// Peripherals (0x50000000 - 0x5007ffff, read-write, execute never)
 	MPU_RBAR = 0x50000000 | MPU_RBAR_VALID | (6 << MPU_RBAR_REGION_LSB);
 	MPU_RASR = MPU_RASR_ENABLE | MPU_RASR_ATTR_PERIPH | MPU_RASR_SIZE_512KB | MPU_RASR_ATTR_AP_PRW_URW | MPU_RASR_ATTR_XN;
+	// SYSCFG_* registers are disabled
+	// (0x40013800 - 0x40013BFF, read-only, execute never)
+	MPU_RBAR = 0x40013800 | MPU_RBAR_VALID | (7 << MPU_RBAR_REGION_LSB);
+	MPU_RASR = MPU_RASR_ENABLE | MPU_RASR_ATTR_PERIPH | MPU_RASR_SIZE_1KB | MPU_RASR_ATTR_AP_PRO_URO | MPU_RASR_ATTR_XN;
 
 	// Enable MPU
-	MPU_CTRL = MPU_CTRL_ENABLE;
+	MPU_CTRL = MPU_CTRL_ENABLE | MPU_CTRL_HFNMIENA;
 
 	// Enable memory fault handler
 	SCB_SHCSR |= SCB_SHCSR_MEMFAULTENA;