| STM32 MPUs |
| ========== |
| |
| STM32 MPUs are microprocessors designed by STMicroelectronics |
| based on Arm Cortex-A. This page presents the common configuration of STM32 |
| MPUs, more details and dedicated configuration can be found in each STM32 MPU |
| page (:ref:`STM32MP1` or :ref:`STM32MP2`) |
| |
| Design |
| ------ |
| The STM32 MPU resets in the ROM code of the Cortex-A. |
| The primary boot core (core 0) executes the boot sequence while |
| secondary boot core (core 1) is kept in a holding pen loop. |
| The ROM code boot sequence loads the TF-A binary image from boot device |
| to embedded SRAM. |
| |
| The TF-A image must be properly formatted with a STM32 header structure |
| for ROM code is able to load this image. |
| Tool stm32image can be used to prepend this header to the generated TF-A binary. |
| |
| Boot |
| ~~~~ |
| Only BL2 (with STM32 header) is loaded by ROM code. The other binaries are |
| inside the FIP binary: BL31 (for Aarch64 platforms), BL32 (OP-TEE), U-Boot |
| and their respective device tree blobs. |
| |
| Boot sequence |
| ~~~~~~~~~~~~~ |
| |
| ROM code -> BL2 (compiled with RESET_TO_BL2) -> OP-TEE -> BL33 (U-Boot) |
| |
| Build Instructions |
| ------------------ |
| Boot media(s) supported by BL2 must be specified in the build command. |
| Available storage medias are: |
| |
| - ``STM32MP_SDMMC`` |
| - ``STM32MP_EMMC`` |
| - ``STM32MP_RAW_NAND`` |
| - ``STM32MP_SPI_NAND`` |
| - ``STM32MP_SPI_NOR`` |
| |
| Serial boot devices: |
| |
| - ``STM32MP_UART_PROGRAMMER`` |
| - ``STM32MP_USB_PROGRAMMER`` |
| |
| Only one storage or serial device should be selected in the build command line, |
| to save space and not overflow SYSRAM size, or else the platform won't build or boot. |
| |
| Other configuration flags: |
| |
| - | ``DTB_FILE_NAME``: to precise board device-tree blob to be used. |
| | Default: stm32mp157c-ev1.dtb |
| - | ``DWL_BUFFER_BASE``: the 'serial boot' load address of FIP, |
| | default location (end of the first 128MB) is used when absent |
| - | ``STM32MP_EARLY_CONSOLE``: to enable early traces before clock driver is setup. |
| | Default: 0 (disabled) |
| - | ``STM32MP_RECONFIGURE_CONSOLE``: to re-configure crash console (especially after BL2). |
| | Default: 0 (disabled) |
| - | ``STM32MP_UART_BAUDRATE``: to select UART baud rate. |
| | Default: 115200 |
| |
| |
| Populate SD-card |
| ---------------- |
| |
| Boot with FIP |
| ~~~~~~~~~~~~~ |
| The SD-card has to be formatted with GPT. |
| It should contain at least those partitions: |
| |
| - fsbl: to copy the tf-a-stm32mp157c-ev1.stm32 binary (BL2) |
| - fip (GUID 19d5df83-11b0-457b-be2c-7559c13142a5): which contains the FIP binary |
| |
| Usually, two copies of fsbl are used (fsbl1 and fsbl2) instead of one partition fsbl. |
| |
| -------------- |
| |
| *Copyright (c) 2023-2024, STMicroelectronics - All Rights Reserved* |