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CNLohr

Next thread Custom HDMI timings/resolution hints in dev

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I just got a copy of the dev branch armbian comipled (2017-04-10).  I'm here with the grand goal of getting libsurvive running with the HTC Vive on the Orange Pi.  In order to do this, I need to coax the OrangePi to output to the vive.

I was skeptical at first, but it appears you guys support 4k@30, so it should be okay on the pixel-clock front.   The vive is 2160x1200@90Hz.  You can't underclock it.  Just won't go then.  It's sadly the only mode the thing supports.

I've seen shreds and bits here and there of information about how to do this, but, it seems that most of it is out-of-date for the "dev" branch.  Any hints on how I can get the OrangePi to output as per the following modeline?

 

Modeline         "Mode 0" 297.00 2160 2200 2220 2266 1200 1228 1230 1464 -hsync -vsync
 


Charles

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2 minutes ago, CNLohr said:

I was skeptical at first, but it appears you guys support 4k@30, so it should be okay on the pixel-clock front.   The vive is 2160x1200@90Hz.  You can't underclock it.  Just won't go then.  It's sadly the only mode the thing supports.

So does it provide the correct EDID mode? Did you try running any image (i.e. Xenial dev nightly from here) and check u-boot output on serial console and dmesg log?

I'm remembering that we wanted to limit maximum resolution to 1080p (just because the text becomes too small to read with 4k) but I'm not sure if this is included in the current driver patch.

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I avoided Xenial because I assumed it would require use of X11, which I want to avoid if all possible because it is a dedicated use.  Perhaps that was an unnecessary fear?  I will give this a shot tonight and see what it says.  Thanks!

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Indeed it does work!!!   Thank you, guys!!! Out of box, too!

 

Now, just to see what the minimal environment for an OGLES/EGL context is.

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Ok... Still a snag.  I can't seem to set the virtual y resolution to any higher than the real y resolution.  This precludes double-buffering (at least in software mode) Any hints how one could reconfigure the framebuffer to allow for double buffering or redirection of the buffer.  Using the fb API doesn't seem to work at all, and neither do the userspace fbset functions :-/.

 

I can pump out 250+ of black per second, but, it's going to take a huge hit if I have to manually copy the data from the backbuffer onto the front :(

 

How can one use custom fb parameters at boot?

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36 minutes ago, CNLohr said:

Any hints how one could reconfigure the framebuffer to allow for double buffering or redirection of the buffer.  Using the fb API doesn't seem to work at all, and neither do the userspace fbset functions :-/.

 

You can't, yet. SimpleFB driver used for now doesn't support anything besides simple framebuffer. Actually, framebuffer is set up by U-Boot and Linux knows only where in memory is located and how big it is, that's all.

 

Proper HDMI driver is in the work by me (already written, but not yet functional, I have to fix all the issues first), which will allow to do all that.

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Do you think it's wiser to more or less wait for that functionality or try to get the mali-with-dev-branch going?  It feels like we're RIGHT on the CUSP of making a fully wireless Vive solution over at libsurvive.  My preference is of course mali support, but, anything to get a video out the door.  Sadly, with neither double-buffering or mali, it's really impossible to do it on the orangepione right now.

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