Bootloader recovery tool

Sniffing around the VF2/JH7110 boot loader recovery tool. This tool is much larger than the JH7100 recover tool (160KB versus <32KB). I guess it was made possible by the much larger boot SRAM in the JH7110 (256KB versus 32KB).

  • The size suggests that the JH7110 recovery tool is based on the U-Boot SPL (i.e. reusing all its infrastructure). Does anybody know if that is correct?

  • The recovery tool has (unsurprisingly) a header that is similar to that added by the spl_tool. However, it is not exact. For example the version field is 0x01010001 instead of 0x01010101. Is there any significance to that? There is also some further data at offset 0x2d4, that is not specified in the spl_tool source. Does anybody have a more complete header description at hand?

  • The recovery tool has a menu option to blow OTP fuses. Is there any documentation about these fuses?

  • The spl_tool source file says that the header is discussed on the page “Creating SPL File”. However, on this page there is no discussion of the header and its contents.

All input welcome!

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Here’s some old discussion.

Thanks for the link!

It would seem that VisionFive and VisionFive 2 info is getting mixed. However, the old VF1 info is interesting context.

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I have created an issue on GitHub to track this: document OTP fuses and secure boot flow · Issue #8 · starfive-tech/Tools · GitHub

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