[lkml]   [2018]   [Oct]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH 0/3] drm: tinydrm driver for adafruit PiTFT 3.5" touchscreen

Den 25.10.2018 18.29, skrev Eric Anholt:
> Eric Anholt <> writes:
>> I was going to start working on making the vc4 driver work with
>> tinydrm panels, but it turned out tinydrm didn't have the panel I had
>> previously bought. So, last night I ported the fbtft staging
>> driver over to DRM.
>> It seems to work (with DT at
>> --
>> fbdev works great including rotated, and so does modetest. However,
>> when X11 comes up at 16bpp, I get:
>> If I have tinydrm set a preferred bpp of 24, X looks great. Noralf,
>> any ideas?
> Also, with these patches and the format modifier patch I just sent, mesa
> with vc4 is now working with this driver on this branch:
> Now I wonder how we can improve performance of the SPI updates.

I just remembered that tinydrm does a full flush on page flips. And if
the dirtyfb ioctl is also used you end up with two flushes. This could
explain bad performance. I have been waiting for the dirtyfb through
atomic work to come to fruition, but nothing merged yet. That would give
dirty tracking on page flips.


 \ /
  Last update: 2018-10-31 17:30    [W:0.207 / U:0.144 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site