Re:Writing to the Framebuffer (2018)
by Jasper_ on Tuesday June 02, 2020 @05:10PM
(#23396354)
Yes. fbdev is kept alive for compatibility (and fbcon) reasons, but it's a really outdated API and drivers have to jump through hoops to support it. Please use dumb buffers when necessary. See a simple example here: https://github.com/magcius/drmdemo
[ Parent
| on HN ]
How can I write a simple device driver using dumb buffers? I have searched far and wide but I can't find anything. I'm forced to write a framebuffer driver. Once you dip into DRI shit get's insanely complex quick.
For the simplest case, where you have contiguous memory for your framebuffer storage and no MMIO, try the CMA helpers: https://github.com/torvalds/linux/blob/master/drivers/gpu/dr...
I wrote a basic device driver for a platform I worked on. It's since been upstreamed and gotten more eyeballs, but it's still relatively simple. https://github.com/torvalds/linux/blob/master/drivers/gpu/dr...
Does the Nvidia proprietary kernel module provide a DRI interface?
Yes, since a few years ago. https://download.nvidia.com/XFree86/Linux-x86_64/396.51/READ...