Re: [PATCH v2 1/1] drm/mediatek: Filter modes according to hardware capability

["Michał Kopeć" <michal@nozomi.space>]

(Re-sending because Shawn's @google email is inactive)

Hi Shawn,

I'm a new owner of the Chromebook Ciri (MT8188) and have run into an 
issue which I believe is related to this patch.

I'm attempting to use a 3440x1440 144Hz monitor over DisplayPort, but 
the available resolutions are limited to 2560x1440@120Hz. I found this 
patch, then I confirmed with the monitor's EDID that i am indeed 
reaching data rates above 8250 (though minimally) in higher resolution 
modes.

I wanted to ask about this comment:

 > The proposed formula is only one way to estimate whether our SoC
 > supports the mode setting. The basic idea behind it is just to check
 > if the data rate requirement is too high (directly proportional to
 > pixel clock, inversely proportional to vbp). Please adjust the
 > function if it doesn't fit your situation in the future.

- Can you confirm if the reference number 8250 is the hard limit of the 
hardware?
- Could you suggest other formulae that could work for my use case? I'd 
be happy to implement and test on my end but as I don't have access to 
MTK documentation, I don't know the actual limits of the hardware and 
how to deal with them

Regards,
Michał Kopeć