PocketBeagle 2

Overview

PocketBeagle 2 is a computational platform powered by TI AM62x SoC (there are two revisions, AM6232 and AM6254).

The board configuration provides support for the ARM Cortex-M4F MCU core.

See the PocketBeagle 2 Product Page for details.

Hardware

PocketBeagle 2 features the TI AM62x SoC based around an Arm Cortex-A53 multicore cluster with an Arm Cortex-M4F microcontroller, Imagination Technologies AXE-1-16 graphics processor (from revision A1) and TI programmable real-time unit subsystem microcontroller cluster coprocessors.

Zephyr is ported to run on the M4F core and the following listed hardware specifications are used:

Low-power ARM Cortex-M4F
Memory
- 256KB of SRAM
- 512MB of DDR4

Currently supported PocketBeagle 2 revisions:

A0: Comes wth SOC AM6232

Supported Features

The pocketbeagle_2 board supports the hardware features listed below.

on-chip / on-board: Feature integrated in the SoC / present on the board.
2 / 2: Number of instances that are enabled / disabled.
Click on the label to see the first instance of this feature in the board/SoC DTS files.
vnd,foo: Compatible string for the Devicetree binding matching the feature.
Click on the link to view the binding documentation.

`pocketbeagle_2@A0/am6232/m4` target

Type	Location	Description	Compatible
CPU	on-chip	ARM Cortex-M4F CPU1	`arm,cortex-m4f`
Clock control	on-chip	Generic fixed-rate clock provider1	`fixed-clock`
GPIO & Headers	on-chip	GPIO Controller for Davinci and Keystone devices1	`ti,davinci-gpio`
I2C	on-chip	TI OMAP I2C Controller1	`ti,omap-i2c`
Interrupt controller	on-chip	ARMv7-M NVIC (Nested Vectored Interrupt Controller)1	`arm,v7m-nvic`
Mailbox	on-chip	TI OMAP MAILBOX1	`ti,omap-mailbox`
Pin control	on-chip	TI K3 Pin Controller1	`ti,k3-pinctrl`
Serial controller	on-chip	ns16550 UART1	`ns16550`
SRAM	on-chip	Generic on-chip SRAM3	`mmio-sram`
Timer	on-chip	ARMv7-M System Tick1	`arm,armv7m-systick`

Devices

System Clock

This board configuration uses a system clock frequency of 400 MHz.

DDR RAM

The board has 512MB of DDR RAM available. This board configuration allocates Zephyr 4kB of RAM (only for resource table: 0x9CC00000 to 0x9CC00400).

Serial Port

This board configuration uses a single serial communication channel with the MCU domain UART (MCU_UART0, i.e. P2.05 as RX and P2.07 as TX).

SD Card

Download BeagleBoard.org’s official BeagleBoard Imaging Utility to create bootable SD-card with the Linux distro image. This will boot Linux on the A53 application cores. These cores will then load the Zephyr binary on the M4 core using remoteproc.

Flashing

The board supports remoteproc using the OpenAMP resource table.

The testing requires the binary to be copied to the SD card to allow the A53 cores to load it while booting using remoteproc.

To test the M4F core, we build the Hello World sample with the following command.

# From the root of the zephyr repository
west build -b pocketbeagle_2/am6232/m4 samples/hello_world

This builds the program and the binary is present in the build/zephyr directory as zephyr.elf.

We now copy this binary onto the SD card in the /lib/firmware directory and name it as am62-mcu-m4f0_0-fw.

# Mount the SD card at sdcard for example
sudo mount /dev/sdX sdcard
# copy the elf to the /lib/firmware directory
sudo cp --remove-destination zephyr.elf sdcard/lib/firmware/am62-mcu-m4f0_0-fw

The SD card can now be used for booting. The binary will now be loaded onto the M4F core on boot.

The binary will run and print Hello world to the MCU_UART0 port.

Debugging

The board supports debugging M4 core from the A53 cores running Linux. Since the target needs superuser privilege, openocd needs to be launched seperately for now:

sudo openocd -f board/ti_am625_swd_native.cfg

Start debugging

west build -b None
west debug