Where is the source code of the bootloader?

HiFive Premier P550
1

Where can I get the source code for bootloaders such as Uboot?

I want to boot this board from USB, but I can’t get UBoot SPL and UBoot (+OpenSBI) which should be flashed to USB.

Thank you

2

In the past, these have been part of the Freedom SDK which hasn’t been released for this product yet. My understanding is that it will be soon.

1 Like
3

I see, I hope it will be released soon. Thanks.

4

Patches are here:

It looks like meta-sifive is using mainline OpenSBI with patches.

1 Like
5

Thanks @drmpeg - I also found the SDK is hiding in plain sight:

1 Like
6

@drmpeg @edolnx Thanks to your help…!! I’ll try them.

7

The SoC supports booting off USB natively. This means whatever USB device would need to have all the necessary partitions for a FSBL, OpenSBI, and a boot loader (U-Boot, Oreboot, etc) on it. There are details of how to enable this with the DIP switches in the SoC Manual starting on page 18 in your PDF reader: https://sifive.cdn.prismic.io/sifive/ZxLjE4F3NbkBXuzW_EIC7700XSOC_Manual_final.pdf