Re: [PATCH v6 1/3] i915/gvt: Introduce the mmio table to support VFIO new mdev API

From: Jani Nikula
Date: Wed Feb 09 2022 - 06:58:03 EST


On Wed, 09 Feb 2022, Christoph Hellwig <hch@xxxxxx> wrote:
> On Tue, Feb 08, 2022 at 05:15:00PM +0200, Jani Nikula wrote:
>> > #ifdef CONFIG_DRM_I915_GVT
>> > +
>> > +#define D_BDW (1 << 0)
>> > +#define D_SKL (1 << 1)
>> > +#define D_KBL (1 << 2)
>> > +#define D_BXT (1 << 3)
>> > +#define D_CFL (1 << 4)
>> > +
>> > +#define D_GEN9PLUS (D_SKL | D_KBL | D_BXT | D_CFL)
>> > +#define D_GEN8PLUS (D_BDW | D_SKL | D_KBL | D_BXT | D_CFL)
>> > +
>> > +#define D_SKL_PLUS (D_SKL | D_KBL | D_BXT | D_CFL)
>> > +#define D_BDW_PLUS (D_BDW | D_SKL | D_KBL | D_BXT | D_CFL)
>> > +
>> > +#define D_PRE_SKL (D_BDW)
>> > +#define D_ALL (D_BDW | D_SKL | D_KBL | D_BXT | D_CFL)
>>
>> If these really need to be in a header in i915/, I think they need to be
>> longer with some namespacing or something. I do wish these could be
>> hidden though.
>
> I think we could actually kill them off entirely. They are used as
> arguments to the macros that setup the mmio table.
>
> Thefunctions to build these tabls are already organized by families,
> so we'd need relatively few conditions to just build them the right
> way. There also are some runtime checks in the callbacks, but they
> seem entirely superflous as far as I can tell.
>
> Only the cmd parser is a bit messy. So maybe we could keep these
> constants just for the cmd parser inside of gvt for now (and clean
> that up later) and remove them entirely from the mmio table.

I'm fine with cleaning this up in follow-up, provided the follow-up
actually happens! ;)

BR,
Jani.


--
Jani Nikula, Intel Open Source Graphics Center