| .. _imx93_evk: |
| |
| NXP i.MX93 EVK |
| ############## |
| |
| Overview |
| ******** |
| |
| The i.MX93 Evaluation Kit (MCIMX93-EVK board) is a platform designed to show |
| the most commonly used features of the i.MX 93 Applications Processor in a |
| small and low cost package. The MCIMX93-EVK 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. |
| |
| i.MX93 MPU is composed of one cluster of 2x Cortex-A55 cores and a single |
| Cortex®-M33 core. Zephyr OS is ported to run on one of the Cortex®-A55 core. |
| |
| - Board features: |
| |
| - 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 |
| - PCI-E M.2 |
| - Connectors: |
| |
| - 40-Pin Dual Row Header |
| - LEDs: |
| |
| - 1x Power status LED |
| - 2x UART LED |
| - Debug |
| |
| - JTAG 20-pin connector |
| - MicroUSB for UART debug, two COM ports for A55 and M33 |
| |
| |
| Supported Features |
| ================== |
| |
| The Zephyr mimx93_evk board Cortex-A Core configuration supports the following |
| hardware features: |
| |
| +-----------+------------+-------------------------------------+ |
| | Interface | Controller | Driver/Component | |
| +===========+============+=====================================+ |
| | GIC-v4 | on-chip | interrupt controller | |
| +-----------+------------+-------------------------------------+ |
| | ARM TIMER | on-chip | system clock | |
| +-----------+------------+-------------------------------------+ |
| | CLOCK | on-chip | clock_control | |
| +-----------+------------+-------------------------------------+ |
| | PINMUX | on-chip | pinmux | |
| +-----------+------------+-------------------------------------+ |
| | UART | on-chip | serial port | |
| +-----------+------------+-------------------------------------+ |
| | GPIO | on-chip | GPIO | |
| +-----------+------------+-------------------------------------+ |
| | TPM | on-chip | TPM Counter | |
| +-----------+------------+-------------------------------------+ |
| | ENET | on-chip | ethernet port | |
| +-----------+------------+-------------------------------------+ |
| |
| The Zephyr imx93_evk board Cortex-M33 configuration supports the following |
| hardware features: |
| |
| +-----------+------------+-------------------------------------+ |
| | Interface | Controller | Driver/Component | |
| +===========+============+=====================================+ |
| | NVIC | on-chip | interrupt controller | |
| +-----------+------------+-------------------------------------+ |
| | SYSTICK | on-chip | systick | |
| +-----------+------------+-------------------------------------+ |
| | CLOCK | on-chip | clock_control | |
| +-----------+------------+-------------------------------------+ |
| | PINMUX | on-chip | pinmux | |
| +-----------+------------+-------------------------------------+ |
| | UART | on-chip | serial port | |
| +-----------+------------+-------------------------------------+ |
| | GPIO | on-chip | GPIO | |
| +-----------+------------+-------------------------------------+ |
| |
| Devices |
| ======== |
| System Clock |
| ------------ |
| |
| This board configuration uses a system clock frequency of 24 MHz. |
| Cortex-A55 Core runs up to 1.7 GHz. |
| Cortex-M33 Core runs up to 200MHz in which SYSTICK runs on same frequency. |
| |
| Serial Port |
| ----------- |
| |
| This board configuration uses a single serial communication channel with the |
| CPU's UART2 for A55 core and M33 core. |
| |
| Board MUX Control |
| ----------------- |
| |
| This board configuration uses a series of digital multiplexers to switch between |
| different board functions. The multiplexers are controlled by a GPIO signal called |
| ``EXP_SEL`` from onboard GPIO expander ADP5585. It can be configured to select |
| function set "A" or "B" by dts configuration if board control module is enabled. |
| The following dts node is defined: |
| |
| .. code-block:: dts |
| |
| board_exp_sel: board-exp-sel { |
| compatible = "imx93evk-exp-sel"; |
| mux-gpios = <&gpio_exp0 4 GPIO_ACTIVE_HIGH>; |
| mux = "A"; |
| }; |
| |
| Following steps are required to configure the ``EXP_SEL`` signal: |
| |
| 1. Enable Kconfig option ``CONFIG_BOARD_MIMX93_EVK_EXP_SEL_INIT``. |
| 2. Select ``mux="A";`` or ``mux="B";`` in ``&board_exp_sel`` devicetree node. |
| |
| Kconfig option ``CONFIG_BOARD_MIMX93_EVK_EXP_SEL_INIT`` is enabled if a board |
| function that requires configuring the mux is enabled. The MUX option is |
| automatically selected if certain board function is enabled, and takes precedence |
| over dts config. For instance, if ``CONFIG_CAN`` is enabled, MUX A is selected |
| even if ``mux="B";`` is configured in dts, and an warning would be reported in |
| the log. |
| |
| Programming and Debugging (A55) |
| ******************************* |
| |
| Copy the compiled ``zephyr.bin`` to the first FAT partition of the SD card and |
| plug the SD card into the board. Power it up and stop the u-boot execution at |
| prompt. |
| |
| Use U-Boot to load and kick zephyr.bin to Cortex-A55 Core1: |
| |
| .. code-block:: console |
| |
| fatload mmc 1:1 0xd0000000 zephyr.bin; dcache flush; icache flush; dcache off; icache off; cpu 1 release 0xd0000000 |
| |
| |
| Or use the following command to kick zephyr.bin to Cortex-A55 Core0: |
| |
| .. code-block:: console |
| |
| fatload mmc 1:1 0xd0000000 zephyr.bin; dcache flush; icache flush; dcache off; icache off; go 0xd0000000 |
| |
| |
| 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: imx93_evk/mimx9352/a55 |
| :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 Booting Zephyr OS build v3.7.0-2055-g630f27a5a867 *** |
| thread_a: Hello World from cpu 0 on imx93_evk! |
| thread_b: Hello World from cpu 0 on imx93_evk! |
| thread_a: Hello World from cpu 0 on imx93_evk! |
| thread_b: Hello World from cpu 0 on imx93_evk! |
| |
| System Reboot (A55) |
| =================== |
| |
| Currently i.MX93 only support cold reboot and doesn't support warm reboot. |
| Use this configuratiuon to verify cold reboot with :zephyr:code-sample:`shell-module` |
| sample: |
| |
| .. zephyr-app-commands:: |
| :zephyr-app: samples/subsys/shell/shell_module |
| :host-os: unix |
| :board: imx93_evk/mimx9352/a55 |
| :goals: build |
| |
| This will build an image with the shell sample app, boot it and execute |
| kernel reboot command in shell command line: |
| |
| .. code-block:: console |
| |
| uart:~$ kernel reboot cold |
| |
| Programming and Debugging (M33) |
| ******************************* |
| |
| Copy the compiled ``zephyr.bin`` to the first FAT partition of the SD card and |
| plug the SD card into the board. Power it up and stop the u-boot execution at |
| prompt. |
| |
| Use U-Boot to load and kick zephyr.bin to Cortex-M33 Core: |
| |
| .. code-block:: console |
| |
| load mmc 1:1 0x80000000 zephyr.bin;cp.b 0x80000000 0x201e0000 0x30000;bootaux 0x1ffe0000 0 |
| |
| 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: imx93_evk/mimx9352/m33 |
| :goals: run |
| |
| 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 v3.7.0-684-g71a7d05ba60a *** |
| thread_a: Hello World from cpu 0 on imx93_evk! |
| thread_b: Hello World from cpu 0 on imx93_evk! |
| thread_a: Hello World from cpu 0 on imx93_evk! |
| thread_b: Hello World from cpu 0 on imx93_evk! |
| |
| To make a container image flash.bin with ``zephyr.bin`` for SD/eMMC programming and booting |
| from BootROM. Refer to user manual of i.MX93 `MCUX SDK release`_. |
| |
| .. _MCUX SDK release: |
| https://mcuxpresso.nxp.com/ |
| |
| References |
| ========== |
| |
| More information can refer to NXP official website: |
| `NXP website`_. |
| |
| .. _NXP website: |
| https://www.nxp.com/products/processors-and-microcontrollers/arm-processors/i-mx-applications-processors/i-mx-9-processors/i-mx-93-applications-processor-family-arm-cortex-a55-ml-acceleration-power-efficient-mpu:i.MX93 |
| |
| |
| Using the SOF-specific variant |
| ****************************** |
| |
| Purpose |
| ======= |
| |
| Since this board doesn't have a DSP, an alternative for people who might be interested |
| in running SOF on this board had to be found. The alternative consists of running SOF |
| on an A55 core using Jailhouse as a way to "take away" one A55 core from Linux and |
| assign it to Zephyr with `SOF`_. |
| |
| .. _SOF: |
| https://github.com/thesofproject/sof |
| |
| What is Jailhouse? |
| ================== |
| |
| Jailhouse is a light-weight hypervisor that allows the partitioning of hardware resources. |
| For more details on how this is done and, generally, about Jailhouse, please see: `1`_, |
| `2`_ and `3`_. The GitHub repo can be found `here`_. |
| |
| .. _1: |
| https://lwn.net/Articles/578295/ |
| |
| .. _2: |
| https://lwn.net/Articles/578852/ |
| |
| .. _3: |
| http://events17.linuxfoundation.org/sites/events/files/slides/ELCE2016-Jailhouse-Tutorial.pdf |
| |
| .. _here: |
| https://github.com/siemens/jailhouse |
| |
| |
| How does it work? |
| ================= |
| Firstly, we need to explain a few Jailhouse concepts that will be referred to later on: |
| |
| * **Cell**: refers to a set of hardware resources that the OS assigned to this |
| cell can utilize. |
| |
| * **Root cell**: refers to the cell in which Linux is running. This is the main cell which |
| will contain all the hardware resources that Linux will utilize and will be used to assign |
| resources to the inmates. The inmates CANNOT use resources such as the CPU that haven't been |
| assigned to the root cell. |
| |
| * **Inmate**: refers to any other OS that runs alongside Linux. The resources an inmate will |
| use are taken from the root cell (the cell Linux is running in). |
| |
| SOF+Zephyr will run as an inmate, alongside Linux, on core 1 of the board. This means that |
| said core will be taken away from Linux and will only be utilized by Zephyr. |
| |
| The hypervisor restricts inmate's/root's access to certain hardware resources using |
| the second-stage translation table which is based on the memory regions described in the |
| configuration files. Please consider the following scenario: |
| |
| Root cell wants to use the **UART** which let's say has its registers mapped in |
| the **[0x0 - 0x42000000]** region. If the inmate wants to use the same **UART** for |
| some reason then we'd need to also add this region to inmate's configuration |
| file and add the **JAILHOUSE_MEM_ROOTSHARED** flag. This flag means that the inmate |
| is allowed to share this region with the root. If this region is not set in |
| the inmate's configuration file and Zephyr (running as an inmate here) tries |
| to access this region this will result in a second stage translation fault. |
| |
| Notes: |
| |
| * Linux and Zephyr are not aware that they are running alongside each other. |
| They will only be aware of the cores they have been assigned through the config |
| files (there's a config file for the root and one for each inmate). |
| |
| Architecture overview |
| ===================== |
| |
| The architecture overview can be found at this `location`_. (latest status update as of now |
| and the only one containing diagrams). |
| |
| .. _location: |
| https://github.com/thesofproject/sof/issues/7192 |
| |
| |
| How to use this board? |
| ====================== |
| |
| This board has been designed for SOF so it's only intended to be used with SOF. |
| |
| TODO: document the SOF build process for this board. For now, the support for |
| i.MX93 is still in review and has yet to merged on SOF side. |