Re: [PATCH v3 1/8] drm/i915/skl: Add support to load SKL CSR firmware

Damien Lespiau
2015-04-13T17:03:01Z

On Mon, Apr 13, 2015 at 07:52:54PM +0300, Imre Deak wrote:
> On Mon, 2015-04-13 at 17:34 +0100, Damien Lespiau wrote:
> > On Mon, Apr 13, 2015 at 03:54:02PM +0530, Animesh Manna wrote:
> > > diff --git a/drivers/gpu/drm/i915/intel_csr.h b/drivers/gpu/drm/i915/intel_csr.h
> > > new file mode 100644
> > > index 0000000..c2a5a53
> > > --- /dev/null
> > > +++ b/drivers/gpu/drm/i915/intel_csr.h
> > > +
> >
> > [...]
> >
> > > +#define I915_CSR_SKL "i915/dmc_gen9.bin"
> >
> > I'm guessing the BXT DMC firwmare will be different from SKL's? Remember
> > that one of the requirements is to be able to have the same OS image
> > boot on both SKL and BXT. That means the firmware names have to be
> > different for SKL and BXT. We probably should have skl in the name here.
> >
> > Also, we need to be able to be able to support "Interface" versions. Ie.
> > if the firmware interface changes in such a way a different loading code
> > is needed, we need to be able to have both firmware on the disk so both
> > an old kernel and a new kernel can work with the same user space.
> >
> > Right now, the naming scheme of the firmware does have a version on it,
> > hopefully that's this "Interface" version.
> >
> > Thoughts?
>
> Yes, the above file name looks incorrect. "dmc_gen9.bin" was the name
> for the firmware image with the old layout. This patchset adds support
> for the new firmware layout starting from ver 1, while the old layout
> doesn't need to be supported. In an earlier version of this patch the
> filename was changed to "i915/skl_dmc_ver1.bin" not sure why that change
> got dropped. I think we could just use this latter name.

First public firmware is already v4 [1], no idea is the version bumps
are actual API/interface changes.

--
Damien

[1] https://01.org/linuxgraphics/downloads/2015/