Use of wayland callback happens at very low rate

[jwinarske]

Describe the bug
Using a Wayland callback produces a very low frame rate callback. It is expected to callback at or near the refresh rate of the attached monitor.

To Reproduce
Steps to reproduce the behavior:

1. Build meta-tegra branch 'master' with MACHINE 'p3768-0000-p3767-0003'
2. include [meta-flutter](https://github.com/meta-flutter/meta-flutter/) branch master.
3. append ivi-homescreen and toyota-connected-tcna-packages-filament-scene-fluorite-examples-demo
4. Build with bitbake argument 'core-image-weston'
5. Deploy OS image to hardware
6. on target image run homescreen -b /usr/share/flutter/toyota-connected-tcna-packages-filament-scene-fluorite-examples-demo/3.32.8/release/ -f
7. See overlay in upper left report low FPS. All other targets this reports near vertical refresh of attached monitor.

Additional context
Will investigate use of Wayland presentation-timing protocol for frame callbacks.

[jwinarske]

https://forums.developer.nvidia.com/t/jetson-orin-nano-super-wayland-callback-happens-at-very-low-rate/344643

[jwinarske]

More digging...

The weston being built in Yocto is oe-core weston. This is in conflict what NVidia is documenting. It seems likely that NVidia is still patching weston. This reference shares image path to weston source (patched and what version?)
https://developer.nvidia.com/docs/drive/drive-os/7.0.3/public/drive-os-linux-sdk/embedded-software-components/DRIVE_AGX_SoC/Windowing/Wayland_Window_System/window_system_wayland_RuntimeConfiguration8.html

It would seem eglexternalplatform can move to 1.2.1 (unclear how/where breaking changes are managed/documented with the graphics dependencies):

DESCRIPTION = "EGL external platform interface"
HOMEPAGE = "https://github.com/NVIDIA/eglexternalplatform"
LICENSE = "MIT"
LIC_FILES_CHKSUM = "file://COPYING;md5=cfa5a0f49cb081823fc5d965566e8298"

SRC_URI = "git://github.com/NVIDIA/eglexternalplatform.git;protocol=https;branch=master"
# corresponds to 1.2.1 tag
SRCREV = "cf9f10589775c1b4d90f1df6f417f8cf1bed7ec6"

inherit meson

[ichergui]

Hi @jwinarske
Any update ? or we can close it.

[jwinarske]

I tested with official NVidia image. They have Weston binaries, but no source. So tracking its pedigree is challenging. I would seem they are patching a version for EGL stream support. His patch series was never shared with the community as some of the referenced threads indicate. They changed their minds.

The problem with Vulkan still exists.

The NVIDIA Linux Vulkan driver supposedly already supports the VK_EXT_present_timing extension. What degree of recent merged spec is in question: KhronosGroup/Vulkan-Docs#1364

Using the Wayland presentation timing protocol with Vulkan WSI Wayland has some strange behavior. Like callbacks are no-op, unless you change presentation mode to mailbox, in which case you need to register first frame callback, then register presentation timing callback. How the use of the Vulkan VK_EXT_present_timing extension fits here is not yet clear.

@ichergui still investigating