ARM: Add STM32 family machine

STMicrolectronics's STM32 series is a family of Cortex-M
microcontrollers. It is used in various applications, and
proposes a wide range of peripherals.

Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Documentation/arm/stm32/overview.txt

@@ -0,0 +1,32 @@
+			STM32 ARM Linux Overview
+			========================
+
+Introduction
+------------
+
+  The STMicroelectronics family of Cortex-M based MCUs are supported by the
+  'STM32' platform of ARM Linux. Currently only the STM32F429 is supported.
+
+
+Configuration
+-------------
+
+  A generic configuration is provided for STM32 family, and can be used as the
+  default by
+	make stm32_defconfig
+
+Layout
+------
+
+  All the files for multiple machine families are located in the platform code
+  contained in arch/arm/mach-stm32
+
+  There is a generic board board-dt.c in the mach folder which support
+  Flattened Device Tree, which means, it works with any compatible board with
+  Device Trees.
+
+
+Document Author
+---------------
+
+  Maxime Coquelin <mcoquelin.stm32@gmail.com>

Documentation/arm/stm32/stm32f429-overview.txt

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+			STM32F429 Overview
+			==================
+
+  Introduction
+  ------------
+	The STM32F429 is a Cortex-M4 MCU aimed at various applications.
+	It features:
+	- ARM Cortex-M4 up to 180MHz with FPU
+	- 2MB internal Flash Memory
+	- External memory support through FMC controller (PSRAM, SDRAM, NOR, NAND)
+	- I2C, SPI, SAI, CAN, USB OTG, Ethernet controllers
+	- LCD controller & Camera interface
+	- Cryptographic processor
+
+  Resources
+  ---------
+	Datasheet and reference manual are publicly available on ST website:
+	- http://www.st.com/web/en/catalog/mmc/FM141/SC1169/SS1577/LN1806?ecmp=stm32f429-439_pron_pr-ces2014_nov2013
+
+  Document Author
+  ---------------
+	Maxime Coquelin <mcoquelin.stm32@gmail.com>