On 25.02.20 09:13, Frieder Schrempf wrote:
Hi Lucas,
On 24.02.20 12:08, Lucas Stach wrote:
On Mo, 2020-02-24 at 10:53 +0000, Schrempf Frieder wrote:
Hi Lucas,
On 24.02.20 11:37, Lucas Stach wrote:
Hi Frieder,
On Mo, 2020-02-24 at 10:28 +0000, Schrempf Frieder wrote:
On 20.02.20 19:58, Chris Healy wrote:
For the jerkey transitions, can you determine if this is a symptom of a low framerate or dropped frames or something else?
Perhaps you can start your app with "GALLIUM_HUD=fps,cpu,draw-calls,frametime". This may give some clues.
The framerate seems ok. I get something between 50 and 70 FPS.
I have a Qt demo app with a menu and an animated 'ball' that moves across the screen. When the menu is visible, the ball movement is really jerky (ball seems to 'jump back and forth' instead of moving linearly).
As soon as I hide the menu and show the animation fullscreen, the movements are perfectly smooth.
Running the same app with software rendering, everything looks good, too.
No idea what that means, though. I probably need to look at the code of the app and do some more experiments to get a better idea of what might cause the distortion.
Unless some of the graphics experts here already have an idea of what can cause and/or how to debug such an issue!?
Which driver is used for the display side? It seems like the display side doesn't properly handle the dma fences used to synchronize scanout and rendering.
I ported/picked the drivers for the LCDIF and DSI controllers from development branch of the 5.4-based vendor kernel [1] to our own v5.4-based kernel [2]. So it is quite probable, that something could be wrong here.
Please just use DRM_MXSFB for the display side, instead of the downstream driver.
Hm, good idea. I somehow forgot about the fact, that there is an upstream driver for the LCDIF controller. On first try I couldn't get it to run on the i.MX8MM, but I suspect that's due to some reset, power-domain or clock setup, that is missing upstream. I will see if I can get any further with this.
So I had a closer look and while the DRM_MXSFB looks ok on its own, I have some problem with the rest of the i.MX8MM display subsystem.
The vendor stack, that I'm currently using integrates into the imx-drm master/core driver [1] that binds all the components of the display subsystem, such as the LCDIF driver and the integrated SEC_DSIM DSI bridge.
And because of my lack of DRM skills, I have no idea how to get the DRM_MXSFB driver to bind to the imx-drm core, instead of running separately and connecting directly to some panel as it is done for i.MX23/28 and i.MX6SX/UL.
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/driv...