Queued up in DRM-Next for the Intel open-source graphics driver ahead of the Linux 7.0 kernel cycle is expanding GPU temperature sensor reporting, multi-device SVM prep, multi-queue support for Crescent Island, Nova Lake display support, and other feature work. With the Linux 6.19 stable release fast approaching, DRM-Next is now focusing in on reading early fixes with concluding feature activity for this next merge window.
Sent out yesterday was the first round of drm-xe-next fixes for Linux 6.20~7.0. There aren’t many fixes for the week but one that does worth noting is disabling of GuC Power DCC strategy for Panther Lake graphics.
The patch disabling Duty Cycle Control “DCC” explains:
“On PTL, the recommendation is to disable DCC(Duty Cycle Control) as it may cause some regressions due to added latencies. Upcoming GuC releases will disable DCC on PTL as well, but we need to force it in KMD so that this behavior is propagated to older kernels.”
So upcoming GuC micro-controller microcode will be disabling DCC but the Intel Xe kernel driver is also disabling it too for cases of not yet having updated microcode.
Duty Cycle Control is one of the power management features of GuC for adjusting the graphics frequency and helping keep the graphics hardware in low-power idle states for short periods of time when possible. Intel GuC Duty Cycle Control in generations prior to now have aimed to help enhance power efficiency but apparently with Panther Lake the latency of DCC is deemed too high. No power numbers or quantifying this change were noted in the patch disabling it for the kernel driver. So we’ll see if this yields any noticeable user impact or not once the Linux 6.20~7.0 kernel rolls out.
That’s the only noteworthy fix with this week’s drm-xe-next-fixes pull.
My Intel Core Ultra X7 358H MSI Core Ultra Series 3 (Panther Lake) laptop arrived last night for Linux testing at Phoronix. Expect initial Panther Lake Linux benchmarks beginning on Monday.
