SiFive Releases HiFive Unleashed RISC-V Open-Source Boot Loader With DDR Initialization

[phoronix]

Phoronix: SiFive Releases HiFive Unleashed RISC-V Open-Source Boot Loader With DDR Initialization

Back in June we brought up how some of the SiFive HiFive Unleashed initialization code was closed-source for this developer board built around the RISC-V open-source processor ISA. One of the pain points was the DDR memory initialization code being closed-source but then SiFive announced they would allow for a fully open-source boot process. They've now made good on their word with their new open-source project...

http://www.phoronix.com/scan.php?page=news_item&px=SiFive-Open-Source-Boot

[johanb]

Open CPU design, no microcode and fully open-source bootloader.
Does that mean that the Freedom U540 SoC is now officially 100% open source then?

[Guest]

A company that actually keeps its promises.

[Shnatsel]

Open CPU design, no microcode and fully open-source bootloader.
Does that mean that the Freedom U540 SoC is now officially 100% open source then?

The linked post says:

We’re still a long way from doing a fully open source, high performance, Linux capable chip – but at least we’re moving the bar forward!

So no. Although it's not clear what is and isn't open-source in that thing.

For a completely open-hardware RISC-V board see https://www.lowrisc.org/

[starshipeleven]

Open CPU design, no microcode and fully open-source bootloader.
Does that mean that the Freedom U540 SoC is now officially 100% open source then?

It's FSF-compliant hardware as it does not run any closed software blob at any point from cold boot, but not 100% open hardware.

As they said in the blog post, the DDR controller and the ethernet controller are commercial IP, not open hardware.

At SiFive we strive to use (or produce) open source IP whenever feasible. While this is viable for simpler interfaces, modern high performance physical interfaces are very complicated and producing IP for them requires a massive development and verification effort. In order to make the HiFive Unleashed available it just wasn’t feasible to develop open source DDR and Ethernet IP at SiFive, so we used some standard commercial IP.

I'm willing to cut them some slack here, given the hardware wizardry needed to implement such controllers properly.

[Jabberwocky]

The linked post says:

So no. Although it's not clear what is and isn't open-source in that thing.

For a completely open-hardware RISC-V board see https://www.lowrisc.org/

It's very interesting to see that Robert Mullins (co founder of raspberry pi) is part of the lowRISC team and that Krste Asanovic (part of SiFive) is on the "Technical Advisory Board".

I wonder if SiFive will partner (or already does) with lowRISC.