[Intel-gfx] [PATCH] drm/i915/display/dp: Remove support for UHBR13.5

[Murthy, Arun R]

> -----Original Message-----
> From: Nikula, Jani <jani.nikula at intel.com>
> Sent: Monday, June 26, 2023 6:02 PM
> To: Murthy, Arun R <arun.r.murthy at intel.com>; intel-
> gfx at lists.freedesktop.org
> Cc: Deak, Imre <imre.deak at intel.com>; Kahola, Mika
> <mika.kahola at intel.com>
> Subject: RE: [PATCH] drm/i915/display/dp: Remove support for UHBR13.5
> 
> On Thu, 22 Jun 2023, "Murthy, Arun R" <arun.r.murthy at intel.com> wrote:
> >> -----Original Message-----
> >> From: Nikula, Jani <jani.nikula at intel.com>
> >> Sent: Wednesday, June 21, 2023 2:27 PM
> >> To: Murthy, Arun R <arun.r.murthy at intel.com>; intel-
> >> gfx at lists.freedesktop.org
> >> Cc: Deak, Imre <imre.deak at intel.com>; Kahola, Mika
> >> <mika.kahola at intel.com>; Murthy, Arun R <arun.r.murthy at intel.com>
> >> Subject: Re: [PATCH] drm/i915/display/dp: Remove support for UHBR13.5
> >>
> >> On Tue, 20 Jun 2023, Arun R Murthy <arun.r.murthy at intel.com> wrote:
> >> > As per the DP2.1 Spec support for UHBR13.5 is optional. Hence
> >> > removing the support for UHBR13.5
> >>
> >> That's just not a proper rationale. Please explain.
> >>
> > Programming for UHBR10 and UHBR20 is similar compared to UHBR13.5 As
> > of now we have validated 10Gbps and 20Gbps. The spec also points out
> > when 20Gbps is supported 13.5Gbps is optional so we have not
> validated/implemented the UHBR13.5 Now we have the DP2.1 compatible
> panel is market, expecting users can come up with UHBR13.5 not working.
> Hence removing the support for 13.5Gbps for now.
> > Maybe once we have support for UHBR13.5 in the driver we can enable
> this.
> 
> What's missing?
> 
Port clock programming, pll values differs.
This table has been in place but some corrections/recheck required.

Thanks and Regards,
Arun R Murthy
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