Re: [PATCH v2 2/6] target/riscv: hardwire mstatus.FS to zero when enable zfinx

[Richard Henderson]

On 12/31/21 9:55 PM, Weiwei Li wrote:
> > This shouldn't be necessary because it should never have been set.
> Yes, I think so. However, I have a question about MSTATUS_MIE and MSTATUS_MPRV, will they 
> be set before cpu reset?

Yes, via warm reset.

> > I would think it would be more correct to have a positive test for RVF, rather than a 
> > negative test for ZFINX?
> It may  deviate from the original value of mstatus_mask with a positive test 
> for RVF.

Oh, you mean misa_ext?  Hmm.  Interesting point.

When F extension is not implemented, FS is either hardwired to zero (without S-mode) or 
optionally zero.  So this looks like an existing bug to be fixed.


r~