| NXP i.MX 8M Series |
| ================== |
| |
| The i.MX 8M family of applications processors based on Arm Corte-A53 and Cortex-M4 |
| cores provide high-performance computing, power efficiency, enhanced system |
| reliability and embedded security needed to drive the growth of fast-growing |
| edge node computing, streaming multimedia, and machine learning applications. |
| |
| imx8mq is dropped in TF-A CI build due to the small OCRAM size, but still actively |
| maintained in NXP official release. |
| |
| Boot Sequence |
| ------------- |
| |
| Bootrom --> SPL --> BL31 --> BL33(u-boot) --> Linux kernel |
| |
| How to build |
| ------------ |
| |
| Build Procedure |
| ~~~~~~~~~~~~~~~ |
| |
| - Prepare AARCH64 toolchain. |
| |
| - Build spl and u-boot firstly, and get binary images: u-boot-spl.bin, |
| u-boot-nodtb.bin and dtb for the target board. |
| |
| - Build TF-A |
| |
| Build bl31: |
| |
| .. code:: shell |
| |
| CROSS_COMPILE=aarch64-linux-gnu- make PLAT=<Target_SoC> bl31 |
| |
| Target_SoC should be "imx8mq" for i.MX8MQ SoC. |
| Target_SoC should be "imx8mm" for i.MX8MM SoC. |
| Target_SoC should be "imx8mn" for i.MX8MN SoC. |
| Target_SoC should be "imx8mp" for i.MX8MP SoC. |
| |
| Deploy TF-A Images |
| ~~~~~~~~~~~~~~~~~~ |
| |
| TF-A binary(bl31.bin), u-boot-spl.bin u-boot-nodtb.bin and dtb are combined |
| together to generate a binary file called flash.bin, the imx-mkimage tool is |
| used to generate flash.bin, and flash.bin needs to be flashed into SD card |
| with certain offset for BOOT ROM. the u-boot and imx-mkimage will be upstreamed |
| soon, this doc will be updated once they are ready, and the link will be posted. |
| |
| TBBR Boot Sequence |
| ------------------ |
| |
| When setting NEED_BL2=1 on imx8mm. We support an alternative way of |
| boot sequence to support TBBR. |
| |
| Bootrom --> SPL --> BL2 --> BL31 --> BL33(u-boot with UEFI) --> grub |
| |
| This helps us to fulfill the SystemReady EBBR standard. |
| BL2 will be in the FIT image and SPL will verify it. |
| All of the BL3x will be put in the FIP image. BL2 will verify them. |
| In U-boot we turn on the UEFI secure boot features so it can verify |
| grub. And we use grub to verify linux kernel. |