Re: fu740 target

[Ben Dooks]

On 27/07/2022 15:38, Bin Meng wrote:
> On Wed, Jul 27, 2022 at 10:24 PM Ben Dooks <qemu@ben.fluff.org> wrote:
> > Is anyone working on adding a sifive-u74 core to the list of supported
> > CPU types? I was looking at full emulation of the Unmatched but at the
> > moment the best we have is sifive-u54 and I think that misses at least
> > two CSRs the sifive-u74 has.
> >
> > Does anyone have plans to add the sifive-u74, and if not, would a plan
> > to add gradual support for it like adding CSRs 0x7c1 and 0x7c2 so we
> > can run an Unmatched U-boot SPL against it.
>
> Adding 0x7c1/7c2 would be a vendor-specific CSR approach?

Part of the FU740 feature disable controls

> > If not, is there a definitive U54->U74 set of public differnces around
> > we could use to start from? I'd like to be able to run a full Unmatched
> > image using qemu at some point to add to the current real-board testing
> > we're doing.
> >
> > (I have a basic addition of the type and the two CSRs as a couple of
> > patches if that would help as a start)
>
> I am not aware of anyone doing U74 modeling in QEMU, but SiFive folks
> (+Frank) may have one downstream as I see they posted several bug
> fixes in the existing U54 model.
>
> Regards,
> Bin

Thanks

--
Ben Dooks                               http://www.codethink.co.uk/
Senior Engineer                         Codethink - Providing Genius

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