ARM: stm32: prepare stm32 family to welcome armv7 architecture

This patch prepares the STM32 machine for the integration of Cortex-A
based microprocessor (MPU), on top of the existing Cortex-M
microcontroller family (MCU). Since both MCUs and MPUs are sharing
common hardware blocks we can keep using ARCH_STM32 flag for most of
them. If a hardware block is specific to one family we can use either
ARM_SINGLE_ARMV7M or ARCH_MULTI_V7 flag.

Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Alexandre Torgue <alexandre.torgue@st.com>

Documentation/arm/stm32/overview.rst

@@ -5,16 +5,17 @@ STM32 ARM Linux Overview
 Introduction
 ------------
 
-The STMicroelectronics family of Cortex-M based MCUs are supported by the
+The STMicroelectronics STM32 family of Cortex-A microprocessors (MPUs) and
-'STM32' platform of ARM Linux. Currently only the STM32F429 (Cortex-M4)
+Cortex-M microcontrollers (MCUs) are supported by the 'STM32' platform of
-and STM32F746 (Cortex-M7) are supported.
+ARM Linux.
 
 Configuration
 -------------
 
-A generic configuration is provided for STM32 family, and can be used as the
+For MCUs, use the provided default configuration:
-default by
         make stm32_defconfig
+For MPUs, use multi_v7 configuration:
+        make multi_v7_defconfig
 
 Layout
 ------
@@ -28,4 +29,6 @@ Device Trees.
 
 :Authors:
 
-Maxime Coquelin <mcoquelin.stm32@gmail.com>
+- Maxime Coquelin <mcoquelin.stm32@gmail.com>
+- Ludovic Barre <ludovic.barre@st.com>
+- Gerald Baeza <gerald.baeza@st.com>

arch/arm/mach-stm32/Kconfig

@@ -1,8 +1,7 @@
-config ARCH_STM32
+menuconfig ARCH_STM32
-	bool "STMicrolectronics STM32"
+	bool "STMicroelectronics STM32 family" if ARM_SINGLE_ARMV7M || ARCH_MULTI_V7
-	depends on ARM_SINGLE_ARMV7M
+	select ARMV7M_SYSTICK if ARM_SINGLE_ARMV7M
 	select ARCH_HAS_RESET_CONTROLLER
-	select ARMV7M_SYSTICK
 	select CLKSRC_STM32
 	select PINCTRL
 	select RESET_CONTROLLER
@@ -10,27 +9,30 @@ config ARCH_STM32
 	help
 	  Support for STMicroelectronics STM32 processors.
 
+if ARCH_STM32
+
+if ARM_SINGLE_ARMV7M
+
 config MACH_STM32F429
-	bool "STMicrolectronics STM32F429"
+	bool "STMicroelectronics STM32F429"
-	depends on ARCH_STM32
 	default y
 
 config MACH_STM32F469
-	bool "STMicrolectronics STM32F469"
+	bool "STMicroelectronics STM32F469"
-	depends on ARCH_STM32
 	default y
 
 config MACH_STM32F746
-	bool "STMicrolectronics STM32F746"
+	bool "STMicroelectronics STM32F746"
-	depends on ARCH_STM32
 	default y
 
 config MACH_STM32F769
 	bool "STMicroelectronics STM32F769"
-	depends on ARCH_STM32
 	default y
 
 config MACH_STM32H743
-	bool "STMicrolectronics STM32H743"
+	bool "STMicroelectronics STM32H743"
-	depends on ARCH_STM32
 	default y
+
+endif # ARMv7-M
+
+endif

arch/arm/mach-stm32/board-dt.c

@@ -6,7 +6,6 @@
  */
 
 #include <linux/kernel.h>
-#include <asm/v7m.h>
 #include <asm/mach/arch.h>
 
 static const char *const stm32_compat[] __initconst = {
@@ -20,5 +19,4 @@ static const char *const stm32_compat[] __initconst = {
 
 DT_MACHINE_START(STM32DT, "STM32 (Device Tree Support)")
 	.dt_compat = stm32_compat,
-	.restart = armv7m_restart,
 MACHINE_END