boards/nxp/frdm_imx91/doc/index.rst

.. zephyr:board:: frdm_imx91

Overview
********

The FRDM-IMX91 board is a low-cost and compact platform designed to show
the most commonly used features of the i.MX 91 Applications Processor in a
small and low cost package. The FRDM-IMX93 board is an entry-level development
board, which helps developers to get familiar with the processor before
investing a large amount of resources in more specific designs.

Hardware
********

- i.MX 91 applications processor

  - The i.MX 91 Applications Processor features an Arm Cortex®-A55 core
    that can operate at speeds of up to 1.4 GHz.
- RAM: 2GB LPDDR4
- Storage:

  - SanDisk 16GB eMMC5.1
  - microSD Socket
- Wireless:

  - Murata Type-2EL (SDIO+UART+SPI) module. It is based on NXP IW612 SoC,
    which supports dual-band (2.4 GHz /5 GHz) 1x1 Wi-Fi 6, Bluetooth 5.2,
    and 802.15.4
- USB:

  - Two USB 2.0 Type C connectors
- Ethernet:

  - ENET: 10/100/1000 Mbit/s RGMII Ethernet connected with external PHY
    YT8521
  - ENET_QoS: 10/100/1000 Mbit/s RGMII Ethernet supporting TSN connected
    with external PHY YT8521
- PCIe:

  - One M.2/NGFF Key E mini card 75-pin connector
- Connectors:

  - 40-Pin Dual Row Header
- LEDs:

  - 1x Power status LED
  - 2x UART LED
- Debug:

  - JTAG 20-pin connector
  - MicroUSB for UART debug


Supported Features
==================

.. zephyr:board-supported-hw::

Devices
========
System Clock
------------

This board configuration uses a system clock frequency of 24 MHz.
Cortex-A55 Core runs up to 1.4 GHz.

Serial Port
-----------

This board configuration uses a single serial communication channel with the
CPU's UART1 for A55 core.

Programming and Debugging
*************************

U-Boot "go" command is used to load and kick Zephyr to Cortex-A55 Core.

Stop the board at U-Boot command line, then need to download Zephyr binary image into
DDR memory, it can use tftp:

.. code-block:: console

    tftp 0x80000000 zephyr.bin

Or copy the Zephyr image ``zephyr.bin`` to SD card and plug the card into the board, for example
if copy the image to the FAT partition of the SD card, use the following U-Boot command to load
the image into DDR memory (assuming the SD card is dev 1, fat partition ID is 1, they could be
changed based on actual partitions):

.. code-block:: console

    fatload mmc 1:1 0x80000000 zephyr.bin;


Then use U-Boot to load and kick zephyr.bin to Cortex-A55 Core:

.. code-block:: console

    dcache off; icache flush; go 0x80000000

Use this configuration to run basic Zephyr applications and kernel tests,
for example, with the :zephyr:code-sample:`synchronization` sample:

.. zephyr-app-commands::
   :zephyr-app: samples/synchronization
   :host-os: unix
   :board: frdm_imx91/mimx9131
   :goals: build

This will build an image with the synchronization sample app, boot it and
display the following console output:

.. code-block:: console

    *** Booting Zephyr OS build v4.2.0-4272-g1cbd317fd85e ***
    thread_a: Hello World from cpu 0 on frdm_imx91!
    thread_b: Hello World from cpu 0 on frdm_imx91!
    thread_a: Hello World from cpu 0 on frdm_imx91!
    thread_b: Hello World from cpu 0 on frdm_imx91!

.. include:: ../../common/board-footer.rst
   :start-after: nxp-board-footer