arch/arm/stm32h5: Add MPU support

arch/arm/src/stm32h5/CMakeLists.txt

@@ -124,6 +124,10 @@ if(CONFIG_STM32_IWDG)
   list(APPEND SRCS stm32_iwdg.c)
 endif()
 
+if(CONFIG_ARM_MPU)
+  list(APPEND SRCS stm32_mpuinit.c)
+endif()
+
 # Required chip type specific files
 
 if(CONFIG_STM32_STM32H5XXXX)

arch/arm/src/stm32h5/Make.defs

@@ -127,6 +127,10 @@ ifeq ($(CONFIG_STM32_IWDG),y)
 CHIP_CSRCS += stm32_iwdg.c
 endif
 
+ifeq ($(CONFIG_ARM_MPU),y)
+CHIP_CSRCS += stm32_mpuinit.c
+endif
+
 ifeq ($(CONFIG_STM32_WWDG),y)
 CHIP_CSRCS += stm32_wwdg.c
 endif

arch/arm/src/stm32h5/hardware/stm32h5xxx_memorymap.h

@@ -60,6 +60,7 @@
 /* System Memory Addresses **************************************************/
 
 #define STM32_SYSMEM_MEM     0x0bf80000
+#define STM32_OTP_BASE       0x08FFF000     /* One-Time Programmable (OTP) memory base address */
 #define STM32_SYSMEM_UID     0x08FFF800     /* The 96-bit unique device identifier */
 #define STM32_SYSMEM_FSIZE   0x08FFF80C     /* Size of Flash memory in Kbytes. */
 #define STM32_SYSMEM_PACKAGE 0x08FFF80E     /* Indicates the device's package type. */

arch/arm/src/stm32h5/stm32_mpuinit.c

@@ -0,0 +1,63 @@
+/****************************************************************************
+ * arch/arm/src/stm32h5/stm32_mpuinit.c
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <assert.h>
+#include <sys/param.h>
+
+#include "mpu.h"
+#include "stm32_mpuinit.h"
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: stm32_mpuinitialize
+ *
+ * Description:
+ *   Configure the MPU.
+ *
+ *   For FLAT build:
+ *     - just reset and enable the MPU with the default background region.
+ *
+ ****************************************************************************/
+
+void stm32_mpuinitialize(void)
+{
+  /* Show MPU information */
+
+  mpu_showtype();
+
+  /* Reset the MPU in case a bootloader left it configured */
+
+  mpu_reset();
+
+  /* Then enable the MPU */
+
+  mpu_control(true, false, true);
+}

arch/arm/src/stm32h5/stm32_mpuinit.h

@@ -0,0 +1,53 @@
+/****************************************************************************
+ * arch/arm/src/stm32h5/stm32_mpuinit.h
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#ifndef __ARCH_ARM_SRC_STM32H5_STM32_MPUINIT_H
+#define __ARCH_ARM_SRC_STM32H5_STM32_MPUINIT_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: stm32_mpuinitialize
+ *
+ * Description:
+ *   Configure the MPU.
+ *
+ *   For FLAT build:
+ *     - just reset and enable the MPU with the default background region.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_ARM_MPU
+void stm32_mpuinitialize(void);
+#else
+#  define stm32_mpuinitialize()
+#endif
+
+#endif /* __ARCH_ARM_SRC_STM32H5_STM32_MPUINIT_H */

arch/arm/src/stm32h5/stm32_start.c

@@ -40,6 +40,10 @@
 #include "stm32_gpio.h"
 #include "stm32_start.h"
 
+#ifdef CONFIG_ARM_MPU
+#  include "stm32_mpuinit.h"
+#endif
+
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
@@ -220,6 +224,15 @@ void __start(void)
 #endif
   showprogress('B');
 
+  /* Configure the MPU to permit user-space access to its FLASH and RAM (for
+   * CONFIG_BUILD_PROTECTED) or to manage cache properties of external
+   * memory regions (in a flat build).
+   */
+
+#ifdef CONFIG_ARM_MPU
+  stm32_mpuinitialize();
+#endif
+
   /* Initialize onboard resources */
 
   stm32_board_initialize();

boards/arm/stm32h5/nucleo-h563zi/src/CMakeLists.txt

@@ -52,6 +52,10 @@ if(CONFIG_STM32_USBFS_HOST)
   list(APPEND SRCS stm32_usb.c)
 endif()
 
+if(CONFIG_ARM_MPU)
+  list(APPEND SRCS stm32_mpu.c)
+endif()
+
 target_sources(board PRIVATE ${SRCS})
 
 set_property(GLOBAL PROPERTY LD_SCRIPT "${NUTTX_BOARD_DIR}/scripts/flash.ld")

boards/arm/stm32h5/nucleo-h563zi/src/Make.defs

@@ -58,6 +58,10 @@ ifeq ($(CONFIG_STM32_USBFS_HOST),y)
 CSRCS += stm32_usb.c
 endif
 
+ifeq ($(CONFIG_ARM_MPU),y)
+CSRCS += stm32_mpu.c
+endif
+
 DEPPATH += --dep-path board
 VPATH += :board
 CFLAGS += ${INCDIR_PREFIX}$(TOPDIR)$(DELIM)arch$(DELIM)$(CONFIG_ARCH)$(DELIM)src$(DELIM)board$(DELIM)board

boards/arm/stm32h5/nucleo-h563zi/src/nucleo-h563zi.h

@@ -115,6 +115,18 @@
 
 int stm32_bringup(void);
 
+/****************************************************************************
+ * Name: stm32_mpu_configure_otp
+ *
+ * Description:
+ *   Initialize MPU and configure the OTP flash region.
+ *
+ ****************************************************************************/
+
+#if defined(CONFIG_ARM_MPU) && defined(CONFIG_STM32_ICACHE)
+void stm32_mpu_configure_otp(void);
+#endif
+
 #ifdef CONFIG_STM32_SPI
 /****************************************************************************
  * Name: stm32_spiregister

boards/arm/stm32h5/nucleo-h563zi/src/stm32_boot.c

@@ -53,6 +53,12 @@
 
 void stm32_board_initialize(void)
 {
+#if defined(CONFIG_ARM_MPU) && defined(CONFIG_STM32_ICACHE)
+  /* Configure OTP MPU region. */
+
+  stm32_mpu_configure_otp();
+#endif
+
 #ifdef CONFIG_ARCH_LEDS
   /* Configure on-board LEDs if LED support has been selected. */
 

boards/arm/stm32h5/nucleo-h563zi/src/stm32_mpu.c

@@ -0,0 +1,41 @@
+/****************************************************************************
+ * boards/arm/stm32h5/nucleo-h563zi/src/stm32_mpu.c
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <debug.h>
+#include <errno.h>
+
+#include <nuttx/arch.h>
+
+#include "hardware/stm32_memorymap.h"
+#include "mpu.h"
+#include "stm32_mpuinit.h"
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: stm32_mpu_configure_otp
+ *
+ * Description:
+ *   Configure the OTP flash region as non-cacheable, non-executable, non-
+ *   shareable, and read-only.
+ *
+ ****************************************************************************/
+
+void stm32_mpu_configure_otp(void)
+{
+  mpu_configure_region(STM32_OTP_BASE, 4096,
+      MPU_RBAR_XN | MPU_RBAR_SH_NO | MPU_RBAR_AP_RORO,
+      MPU_RLAR_NONCACHEABLE);
+}