Secure boot verifying bootloader and kernel: Same DTB file in both?

Dial — Thu, 24 Mar 2022 09:19:30 GMT

Hello:

I am trying to set up a secure boot for the bottloader and kernel in the iMX8MP following the instructions in the URL https://source.codeaurora.org/external/imx/uboot-imx/tree/doc/imx/habv4/guides/mx8m_mx8mm_secure_boot.txt?h=imx_v2018.03_4.14.98_2.0.0_ga

According to the instructions, a DTB file is required to assembly the signed bootloader:

1.3 Preparing the fit image
----------------------------

The imx-mkimage project is used to combines all the images in a single
flash.bin binary, the following files are required:

- U-Boot:
  u-boot.bin
  u-boot-nodtb.bin
  u-boot-spl.bin
  U-Boot DTB file (e.g. fsl-imx8mq-evk.dtb)

But then a DTB file is also required with the kernel, as can be seen in the CSF file in https://source.codeaurora.org/external/imx/uboot-imx/tree/doc/imx/habv4/csf_examples/additional_images/csf_additional_images.txt?h=imx_v2018.03_4.14.98_2.0.0_ga.

[Authenticate Data]
    # Key slot index used to authenticate the image data
    Verification index = 2
    # Authenticate Start Address, Offset, Length and file
    Blocks = 0x80800000 0x00000000 0x006EA000 "zImage", \
	     0x83800000 0x00000000 0x0000B927 "imx7d-sdb.dtb", \
	     0x84000000 0x00000000 0x000425B8 "uTee-7dsdb"

Are these DTB files the same file? If not, which are the differences?

Thank you very much in advance and best regards.

topic Secure boot verifying bootloader and kernel: Same DTB file in both? in i.MX Processors

Secure boot verifying bootloader and kernel: Same DTB file in both?