boards: Add support for Silicon Labs' BRD4255A Radio board

This commit adds support for Silicon Labs BRD4255A (a.k.a. SLWRB4255A)
Flex Gecko Radio Board.

Signed-off-by: Yonatan Schachter <yonatan.schachter@gmail.com>

boards/arm/efr32_radio/Kconfig.board

@@ -1,4 +1,5 @@
-# EFR32BG13 BRD4104A / EFR32MG21 BRD4180A board
+# EFR32BG13 BRD4104A / EFR32MG21 BRD4180A /
+# EFR32FG1P BRD4250B / EFR32FG13P BRD4255A board
 
 # Copyright (c) 2020 Piotr Mienkowski
 # Copyright (c) 2020 TriaGnoSys GmbH
@@ -21,3 +22,9 @@ config BOARD_EFR32_RADIO_BRD4180A
 	depends on SOC_SERIES_EFR32MG21
 	select BOARD_EFR32_RADIO
 	select SOC_PART_NUMBER_EFR32MG21A020F1024IM32
+
+config BOARD_EFR32_RADIO_BRD4255A
+	bool "Silicon Labs BRD4255A (Flex Gecko Radio Board)"
+	depends on SOC_SERIES_EFR32FG13P
+	select BOARD_EFR32_RADIO
+	select SOC_PART_NUMBER_EFR32FG13P233F512GM48

boards/arm/efr32_radio/Kconfig.defconfig

@@ -10,6 +10,7 @@ config BOARD
 	default "efr32_radio_brd4104a" if BOARD_EFR32_RADIO_BRD4104A
 	default "efr32_radio_brd4250b" if BOARD_EFR32_RADIO_BRD4250B
 	default "efr32_radio_brd4180a" if BOARD_EFR32_RADIO_BRD4180A
+	default "efr32_radio_brd4255a" if BOARD_EFR32_RADIO_BRD4255A
 
 config CMU_HFXO_FREQ
 	default 38400000

boards/arm/efr32_radio/board.cmake

@@ -8,6 +8,8 @@ elseif(CONFIG_BOARD_EFR32_RADIO_BRD4250B)
 board_runner_args(jlink "--device=EFR32FG1PxxxF256")
 elseif(CONFIG_BOARD_EFR32_RADIO_BRD4180A)
 board_runner_args(jlink "--device=EFR32MG21AxxxF1024")
+elseif(CONFIG_BOARD_EFR32_RADIO_BRD4255A)
+board_runner_args(jlink "--device=EFR32FG13PxxxF512")
 endif()
 
 include(${ZEPHYR_BASE}/boards/common/openocd.board.cmake)

boards/arm/efr32_radio/doc/brd4255a.rst

@@ -0,0 +1,113 @@
+.. _efr32_radio_brd4255a:
+
+EFR32 BRD4255A (SLWRB4255A)
+###########################
+
+Overview
+********
+
+The EFR32FG13P Flex Gecko 2.4 GHz and 915 MHz Radio Board is delivered as a
+`standalone Proprietary Wireless radio board`_. It contains a EFR32FG13P Wireless
+SoC built on an ARM Cortex®-M4F processor with excellent low power capabilities.
+
+.. figure:: ./efr32fg13-slwrb4255a.jpg
+   :height: 262px
+   :align: center
+   :alt: SLWRB4255A Flex Gecko 2.4 GHz and 915 MHz Radio Board
+
+   SLWRB4255A (image courtesy of Silicon Labs)
+
+The BRD4255A a.k.a. SLWRB4255A radio board plugs into the Wireless Starter Kit
+Mainboard BRD4001A and is supported as one of :ref:`efr32_radio`.
+
+Hardware
+********
+
+- EFR32FG13P233F512GM48 Flex Gecko SoC
+- CPU core: ARM Cortex®-M4 with FPU
+- Flash memory: 512 kB
+- RAM: 64 kB
+- Transmit power: up to 19 dBm
+- Operation frequency: 2.4 GHz, 915 MHz
+- Crystals for LFXO (32.768 kHz) and HFXO (38.4 MHz).
+
+For more information about the EFR32FG13 SoC and BRD4255A board, refer to these
+documents:
+
+- `EFR32FG13 Website`_
+- `EFR32FG13 Datasheet`_
+- `EFR32xG13 Reference Manual`_
+- `BRD4255A Reference Manual`_
+
+Supported Features
+==================
+
+Please refer to
+:ref:`EFR32 Radio Board Supported Features <efr32_radio_supported_features>`
+for details of the configuration and common features supported by the
+efr32_radio_brd4255a board.
+
+The default configuration can be found in the defconfig file:
+
+	``boards/arm/efr32_radio/efr32_radio_brd4255a_defconfig``
+
+System Clock
+============
+
+The EFR32FG13P SoC is configured to use the 38.4 MHz external oscillator on the
+board.
+
+Serial Port
+===========
+
+The EFR32FG13P SoC has three USARTs and one Low Energy UARTs (LEUART).
+USART0 is connected to the board controller and is used for the console.
+
+Programming and Debugging
+*************************
+
+Please refer to
+:ref:`Programming and Debugging EFR32 Radio Board <efr32_radio_programming>`
+for details on the supported debug interfaces.
+
+Flashing
+========
+
+Connect the BRD4001A board with a mounted BRD4255A radio module to your host
+computer using the USB port.
+
+Here is an example for the :ref:`hello_world` application.
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/hello_world
+   :board: efr32_radio_brd4255a
+   :goals: flash
+
+Open a serial terminal (minicom, putty, etc.) with the following settings:
+
+- Speed: 115200
+- Data: 8 bits
+- Parity: None
+- Stop bits: 1
+
+Reset the board and you should see the following message in the terminal:
+
+.. code-block:: console
+
+   Hello World! efr32_radio_brd4255a
+
+
+.. _EFR32FG13 Website:
+   https://www.silabs.com/wireless/proprietary/efr32fg13-series-1-sub-ghz-2-4-ghz-socs
+
+.. _EFR32FG13 Datasheet:
+   https://www.silabs.com/documents/public/data-sheets/efr32fg13-datasheet.pdf
+
+.. _EFR32xG13 Reference Manual:
+   https://www.silabs.com/documents/public/reference-manuals/efr32xg13-rm.pdf
+
+.. _standalone Proprietary Wireless radio board:
+   https://www.silabs.com/development-tools/wireless/proprietary/slwrb4255a-efr32fg13-915-mhz-radio-board
+
+.. _BRD4255A Reference Manual:
+   https://www.silabs.com/documents/public/reference-manuals/brd4255a-rm.pdf

boards/arm/efr32_radio/doc/index.rst

@@ -9,6 +9,7 @@ EFR32 Radio Boards
    brd4104a.rst
    brd4250b.rst
    brd4180a.rst
+   brd4255a.rst
 
 Overview
 ********

boards/arm/efr32_radio/efr32_radio_brd4255a.dts

@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2020 Piotr Mienkowski
+ * Copyright (c) 2021 Yonatan Schachter
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/dts-v1/;
+#include <silabs/efr32fg13p233f512gm48.dtsi>
+#include "efr32_radio.dtsi"
+
+/ {
+	model = "Silicon Labs BRD4255A (Flex Gecko Radio Board)";
+	compatible = "silabs,efr32_radio_brd4255a", "silabs,efr32fg13p";
+};
+
+&cpu0 {
+	clock-frequency = <38400000>;
+};
+
+&flash0 {
+	partitions {
+		compatible = "fixed-partitions";
+		#address-cells = <1>;
+		#size-cells = <1>;
+
+		/* Reserve 32 kB for the bootloader */
+		boot_partition: partition@0 {
+			label = "mcuboot";
+			reg = <0x0 0x00008000>;
+			read-only;
+		};
+
+		/* Reserve 220 kB for the application in slot 0 */
+		slot0_partition: partition@8000 {
+			label = "image-0";
+			reg = <0x0008000 0x00037000>;
+		};
+
+		/* Reserve 220 kB for the application in slot 1 */
+		slot1_partition: partition@3f000 {
+			label = "image-1";
+			reg = <0x0003f000 0x00037000>;
+		};
+
+		/* Reserve 32 kB for the scratch partition */
+		scratch_partition: partition@76000 {
+			label = "image-scratch";
+			reg = <0x00076000 0x00008000>;
+		};
+
+		/* Set 8Kb of storage at the end of the 512KB of flash */
+		storage_partition: partition@7e000 {
+			label = "storage";
+			reg = <0x0007e000 0x00002000>;
+		};
+
+	};
+};

boards/arm/efr32_radio/efr32_radio_brd4255a.yaml

@@ -0,0 +1,21 @@
+identifier: efr32_radio_brd4255a
+name: BRD4255A
+type: mcu
+arch: arm
+ram: 64
+flash: 512
+toolchain:
+  - zephyr
+  - gnuarmemb
+  - xtools
+supported:
+  - counter
+  - gpio
+  - nvs
+  - spi
+  - uart
+  - watchdog
+testing:
+  ignore_tags:
+    - net
+    - bluetooth

boards/arm/efr32_radio/efr32_radio_brd4255a_defconfig

@@ -0,0 +1,14 @@
+# SPDX-License-Identifier: Apache-2.0
+
+CONFIG_SOC_SERIES_EFR32FG13P=y
+CONFIG_BOARD_EFR32_RADIO_BRD4255A=y
+CONFIG_ARM_MPU=y
+CONFIG_CONSOLE=y
+CONFIG_UART_CONSOLE=y
+CONFIG_SERIAL=y
+CONFIG_CORTEX_M_SYSTICK=y
+CONFIG_GPIO=y
+CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC=38400000
+CONFIG_CMU_HFCLK_HFXO=y
+CONFIG_SOC_GECKO_EMU_DCDC=y
+CONFIG_SOC_GECKO_EMU_DCDC_MODE_ON=y