welshgeekboy
Posts: 24
Joined: Wed Feb 17, 2016 8:59 am
Location: Wales, Carmarthenshire

HDMIPi settings don't work with Open GL enabled?

Thu Jun 09, 2016 6:27 pm

Hi, I've just booted my Pi 3 for the first time (I have used Pis before, just never a Pi 3 :) ) and I found that the settings in

Code: Select all

/boot/config.txt
for HDMIPi optimisation (1280x800 pix, 60 Hz I think) seem to be ignored when I enable the Open GL support.

So my file looks like this:

Code: Select all

# /boot/config.txt
# For more options and information see
# http://www.raspberrypi.org/documentation/configuration/config-txt.md

disable_overscan=1
#gpu_mem=128
#dtoverlay=vc4-kms-v3d

hdmi_ignore_edid=0xa5000080
hdmi_group=2
hdmi_drive=2
hdmi_mode=28
or the same but with the "dtoverlay" line uncommented, if I have enabled the driver.

What happens is the Pi boots with the correct settings for the HDMIPi when the "dtoverlay" line is commented out, and boots to a screen resolution of 1920x1080 when "dtoverlay" is uncommented. What should I do to have the correct settings for the HDMIPi AND use enable the Open GL driver? Or this not possible?

Thanks all.
Pi B r2, Pi Zero (no cam), Pi 3, acid yellow HDMIPi, lots of robot bits.

User avatar
DougieLawson
Posts: 38774
Joined: Sun Jun 16, 2013 11:19 pm
Location: A small cave in deepest darkest Basingstoke, UK
Contact: Website Twitter

Re: HDMIPi settings don't work with Open GL enabled?

Fri Jun 10, 2016 8:30 am

The OpenGL stuff is still experimental, it's not, yet, guaranteed to work with all displays.
Note: Any requirement to use a crystal ball or mind reading will result in me ignoring your question.

Criticising any questions is banned on this forum.

Any DMs sent on Twitter will be answered next month.
All non-medical doctors are on my foes list.

6by9
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 8670
Joined: Wed Dec 04, 2013 11:27 am
Location: ZZ9 Plural Z Alpha, aka just outside Cambridge.

Re: HDMIPi settings don't work with Open GL enabled?

Fri Jun 10, 2016 8:38 am

And everything in config.txt is processed by the firmware, not Linux. One of the major things about the OpenGL driver is that it is all upstreamed kernel code with almost no GPU firmware interaction.
(dtoverlay and dtparam values in there modify the device tree that gets passed to the kernel, but all that processing is done on the GPU).
Software Engineer at Raspberry Pi Trading. Views expressed are still personal views.
I'm not interested in doing contracts for bespoke functionality - please don't ask.

User avatar
rpiMike
Posts: 1303
Joined: Fri Aug 10, 2012 12:38 pm
Location: Cumbria, UK

Re: HDMIPi settings don't work with Open GL enabled?

Fri Jun 10, 2016 9:36 am


Return to “Graphics, sound and multimedia”