[Intel-gfx] [v2 1/2] drm/i915/display: Add support for darskscreen detection

[Garg, Nemesa]

Hi Jani,

Sometimes there is an issue of black screen on the display due to number of errors like invalid input buffers (black), some issue with display programming (no planes enabled, LUTs zeroed) which means some problem with DE. Upon detection following steps can be taken:
1.Print in dmesg so user can be aware of this issue upon checking the logs
2. Correction steps can be taken and the design is in progress and will come up with follow up patches.

Thanks and Regards,
Nemesa

> -----Original Message-----
> From: Jani Nikula <jani.nikula at linux.intel.com>
> Sent: Friday, October 27, 2023 4:40 PM
> To: Garg, Nemesa <nemesa.garg at intel.com>; intel-gfx at lists.freedesktop.org
> Subject: Re: [Intel-gfx] [v2 1/2] drm/i915/display: Add support for darskscreen
> detection
> 
> On Fri, 27 Oct 2023, Nemesa Garg <nemesa.garg at intel.com> wrote:
> > Darkscreen detection checks if all the pixels of the frame are less
> > then or equal to the comparision value. The comparision value is set
> > to 256 i.e black. So upon getting black pixels from the pipe, the dark
> > screen detect bit is set and an error message will be printed.
> 
> Okay, this still describes *what* the patch does, but not *why*. Why do we need
> this? What for?
> 
> (Please just reply here for starters, instead of resending.)
> 
> 
> BR,
> Jani.
> 
> 
> --
> Jani Nikula, Intel