Re: [PATCH v3] PCI: Unify ECAM constants in native PCI Express drivers

Krzysztof Wilczyński
2020-10-02T20:22:12Z

Hi Rob,

[...]
> What about vmd which I mentioned? I also found iproc and brcmstb are
> ECAM (well, same shifts, but indirect addressing).
[...]

I wanted to cover these (and some others I also found) in a separate
patch, especially since some of the drivers don't explicitly claim to
support ECAM - but I will include these changes in the v4.

> > +/
> > + * Enhanced Configuration Access Mechanism (ECAM)
> > + *
> > + * N.B. This is a non-standard platform-specific ECAM bus shift value. For
> > + * standard values defined in the PCI Express Base Specification see
> > + * include/linux/pci-ecam.h.
> > + */
> > +#define XGENE_PCIE_ECAM_BUS_SHIFT 16
>
> Isn't this just CAM? Though perhaps CAM on PCIe is not standard...
>
> For CAM, there's also tegra, ftpci100, mvebu, and versatile. I think
> I'd drop CAM from this patch and do all of those in a separate patch.

Will do.

Bjorn was also not convinced about referring to things as "CAM" since
the specification (the one I quoted in the patch) does not name it as
such, and rather refers to it as Type 1 access of the PCI bus
configuration space.

Krzysztof