Re: [PATCH V5 2/5] PCI/TPH: Add Steering Tag support

Simon Horman
2024-09-17T16:24:50Z

On Tue, Sep 17, 2024 at 05:14:10PM +0100, Simon Horman wrote:
> On Tue, Sep 17, 2024 at 09:31:00AM -0500, Wei Huang wrote:
> >
> >
> > On 9/17/24 02:32, Simon Horman wrote:
> > > On Mon, Sep 16, 2024 at 03:51:00PM -0500, Wei Huang wrote:
> > ...
> > >> + val = readl(vec_ctrl);
> > >> + mask = PCI_MSIX_ENTRY_CTRL_ST_LOWER | PCI_MSIX_ENTRY_CTRL_ST_UPPER;
> > >> + val &= ~mask;
> > >> + val |= FIELD_PREP(mask, (u32)tag);
> > >
> > > Hi Wei Huang,
> > >
> > > Unfortunately clang-18 (x86_64, allmodconfig, W=1, when applied to net-next)
> > > complains about this. I think it is because it expects FIELD_PREP to be
> > > used with a mask that is a built-in constant.
> >
> > I thought I fixed it, but apparently not enough for clang-18. I will
> > address this problem, along with other comments from you and Bjorn (if any).
> >
> > BTW there is another code in drivers/gpu/drm/ using a similar approach.
>
> Thanks,
>
> I will run some checks over drivers/gpu/drm/ and let you know if they find
> anything.

FWIIW, I did try compiling all the .c files under drivers/gpu/drm/ with
clang-18, and it did not flag this problem.