I’ve been reading through the SiFive FU540-C000 Manual v1p0 which was released in April 2018. I’ve noticed a few omissions from the PRCI register map in section 7.3: it stops at offset 0x28, while the FSBL uses registers from 0x2C - namely the UX00PRCI_CLKMUXSTATUSREG (for the TLCLKSEL register), which appears to be undocumented.
Are there any plans to publish any updates to that document? Or is it expected that software ignore the TLCLKSEL register and only support 1GHz operation in future?
We have stopped producing the FU540-C000 ASIC and the HiFive Unleashed board. Further docs updates are unlikely at this point, and if they occur will likely be very limited in scope. We didn’t have any tech writers when we released this product. I expect we will do better on the next one.
If a register is used by the FSBL then I think it is safe to say it is supported.
Hi Rebecca,
Thanks for spotting this omission! Our documentation team is working on a revision and your feedback has been added to their TODO list. If there are any other issues you noticed, please let us know and I’ll pass them along. We appreciate your alert reading.
Best,
Nick Knight
Technical Lead, Software Performance Team