From e66423229a1581001f630f4b5615a2ed969c1ea7 Mon Sep 17 00:00:00 2001
From: David Sidrane <David.Sidrane@NscDg.com>
Date: Wed, 22 Sep 2021 10:48:09 -0700
Subject: [PATCH] stm32f7:Support CONFIG_MPU_RESET and
 CONFIG_ARM_MPU_EARLY_RESET

---
 arch/arm/src/stm32f7/Make.defs       | 2 +-
 arch/arm/src/stm32f7/stm32_mpuinit.c | 4 ++++
 arch/arm/src/stm32f7/stm32_start.c   | 5 +++++
 3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/arch/arm/src/stm32f7/Make.defs b/arch/arm/src/stm32f7/Make.defs
index 73f01e1457..5ed5c2ff2f 100644
--- a/arch/arm/src/stm32f7/Make.defs
+++ b/arch/arm/src/stm32f7/Make.defs
@@ -67,7 +67,7 @@ ifeq ($(CONFIG_ARMV7M_ITMSYSLOG),y)
 CMN_CSRCS += arm_itm_syslog.c
 endif
 
-ifeq ($(CONFIG_ARM_MPU),y)
+ifneq ($(filter y,$(CONFIG_ARM_MPU) $(CONFIG_ARM_MPU_EARLY_RESET)),)
 CMN_CSRCS += arm_mpu.c
 endif
 
diff --git a/arch/arm/src/stm32f7/stm32_mpuinit.c b/arch/arm/src/stm32f7/stm32_mpuinit.c
index f0564cb056..3f26945b48 100644
--- a/arch/arm/src/stm32f7/stm32_mpuinit.c
+++ b/arch/arm/src/stm32f7/stm32_mpuinit.c
@@ -70,6 +70,10 @@ void stm32_mpuinitialize(void)
 
   mpu_showtype();
 
+  /* Reset MPU if enabled */
+
+  mpu_reset();
+
   /* Configure user flash space */
 
   mpu_user_flash(USERSPACE->us_textstart,
diff --git a/arch/arm/src/stm32f7/stm32_start.c b/arch/arm/src/stm32f7/stm32_start.c
index 162fc98f62..ab30641c3a 100644
--- a/arch/arm/src/stm32f7/stm32_start.c
+++ b/arch/arm/src/stm32f7/stm32_start.c
@@ -35,6 +35,7 @@
 #include "arm_arch.h"
 #include "arm_internal.h"
 #include "nvic.h"
+#include "mpu.h"
 #include "barriers.h"
 
 #include "stm32_rcc.h"
@@ -261,6 +262,10 @@ void __start(void)
                    "r"(CONFIG_IDLETHREAD_STACKSIZE - 64) :);
 #endif
 
+  /* If enabled reset the MPU */
+
+  mpu_early_reset();
+
   /* Clear .bss.  We'll do this inline (vs. calling memset) just to be
    * certain that there are no issues with the state of global variables.
    */