Bug 508667

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SUMMARY
In the arch update 6.4.4-4, the change at https://invent.kde.org/plasma/kwin/-/commit/7d36003c.patch was backported. As a result of this change, if you have a dGPU that takes a moment to wake from d3cold/d3hot, opening windows will take considerable time if in this state.
This is seen on the Framework 16 with the dedicated AMD GPU bay. While windows are not spawned on the dGPU, it still waits for the wakeup.

Calling `echo on | sudo tee /sys/bus/pci/devices/0000:03:00.0/power/control` completely stops the hangs, by forcing the gpu to never reach D3cold (auto being the default). This can also be further tuned by writing to `/sys/bus/pci/devices/0000:03:00.0/power/autosuspend_delay_ms` which affects how long it takes to hit a low power state.

STEPS TO REPRODUCE
1. Have a machine with an AMD GPU that correctly goes into d3cold
2. Open a new window for any program, see a delay as it starts up
3. Start another before it hits cold, see window opens immediately.
4. Wait to hit d3 again, try again, delay.
5. Turn off autosuspend, see the problem go away.

OBSERVED RESULT
Delay in window appearing

EXPECTED RESULT
Window appears immediately, as it did before this patch

SOFTWARE/OS VERSIONS
Operating System: Arch Linux 
KDE Plasma Version: 6.4.4
KDE Frameworks Version: 6.17.0
Qt Version: 6.9.1
Kernel Version: 6.16.3-zen1-1-zen (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 7840HS w/ Radeon 780M Graphics
Memory: 96 GiB of RAM (86.2 GiB usable)
Graphics Processor 1: AMD Radeon RX 7700S
Graphics Processor 2: AMD Radeon 780M Graphics

ADDITIONAL INFORMATION
Machine is a Framework 16.
State when suspended:
```
❯ cat /sys/bus/pci/devices/0000:03:00.0/power_state
D3cold
```