Re: [PATCH v1 4/5] fpga: dfl: add generic support for MSIX interrupts

[matthew . gerlach]

On Tue, 6 Sep 2022, Andy Shevchenko wrote:

> On Tue, Sep 06, 2022 at 12:04:25PM -0700, matthew.gerlach@xxxxxxxxxxxxxxx wrote:
> > From: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx>
> >
> > Define and use a DFHv1 parameter to add generic support for MSIX
> > interrupts for DFL devices.
>
> ...
>
> > +	if (fid != FEATURE_ID_AFU && fid != PORT_FEATURE_ID_ERROR &&
> > +	    fid != PORT_FEATURE_ID_UINT && fid != FME_FEATURE_ID_GLOBAL_ERR) {
> > +		v = readq(base);
> > +		v = FIELD_GET(DFH_VERSION, v);
> > +
> > +		if (v == 1) {
> > +			v =  readq(base + DFHv1_CSR_SIZE_GRP);
>
> I am already lost what v keeps...
>
> Perhaps
>
> 		v = readq(base);
> 		switch (FIELD_GET(DFH_VERSION, v)) {
> 		case 1:
> 			...
> 			break;
> 		}

How about?
		if (FIELD_GET(DFH_VERSION, readq(base)) == 1) {
			...
		}
> > +			if (FIELD_GET(DFHv1_CSR_SIZE_GRP_HAS_PARAMS, v)) {
>
> 				void __iomem *v1hdr = base + DFHv1_PARAM_HDR;
>
> > +				off = dfl_find_param(base + DFHv1_PARAM_HDR, ofst,
> > +						     DFHv1_PARAM_ID_MSIX);
>
> 				off = dfl_find_param(v1hdr, ofst, DFHv1_PARAM_ID_MSIX);
>
> > +				if (off >= 0) {
> > +					ibase = readl(base + DFHv1_PARAM_HDR +
> > +						      off + DFHv1_PARAM_MSIX_STARTV);
> > +					inr = readl(base + DFHv1_PARAM_HDR +
> > +						    off + DFHv1_PARAM_MSIX_NUMV);
>
> 					ibase = readl(v1hdr + off + DFHv1_PARAM_MSIX_STARTV);
> 					inr = readl(v1hdr + off + DFHv1_PARAM_MSIX_NUMV);
>
> > +					dev_dbg(binfo->dev, "%s start %d num %d fid 0x%x\n",
> > +						__func__, ibase, inr, fid);
>
> No __func__ for dev_dbg(). Dynamic debug has this feature at runtime!
>
> > +				}
> > +			}
> > +		}
> > +	}
>
> ...
>
> > +/*
>
> If it's a kernel doc, make it to be parsable as a such.

Yes, the intention is kernel doc. Thanks for the feedback. I
will fix this and add the newline as suggested below.

Matthew Gerlach

> > + * dfl_find_param() - find the offset of the given parameter
> > + * @base: base pointer to start of dfl parameters in DFH
> > + * @max: maximum offset to search
> > + * @param: id of dfl parameter
> > + *
> > + * Return: positive offset on success, negative error code otherwise.
> > + */
> > +int dfl_find_param(void __iomem *base, resource_size_t max, int param);
>
> + blank line.
>
> >  #endif /* __LINUX_DFL_H */
>
> --
> With Best Regards,
> Andy Shevchenko