On TX1/TK1, can we use frame buffer device to display video on HDMI output without getting screen tearing ?
Does FBIO_WAITFORVSYNC avoid screen tearing when frame buffer is used ?
We already test to display video on V4L2 output device which works without getting screen tearing.
Our requirements also included to have
- a 60fps HDMI output
- with a copyless software API supporting MMAPed buffer
- with a low latency from buffer to display (< 33ms)
- with no lose of frame from buffer to HDMI display
From a our point of view, linux frame buffer API
- is not a copyless API if the fb driver has only one buffer
- could be a copyless if it does support multiple buffers and buffer swapping in respect of the screen tearing defect that is forbidden in our use case.
Do you have any feedback on multiple buffers usage of your Linux FB HDMI driver ?
Do you know any API that will fully comply with our requirements ?
In fact, FBIO_WAITFORVSYNC is not a primary feature, it is there for legacy support. I don’t suggest you directly doing fb operation. It would be better if using X11.