AMDGPU DRM Gets "GFXOFF" Patches To Turn Off Graphics Engine

[phoronix]

Phoronix: AMDGPU DRM Gets "GFXOFF" Patches To Turn Off Graphics Engine

AMD's Huang Rui has posted a set of 20 patches providing "GFXOFF" support for the AMDGPU Direct Rendering Manager Linux kernel driver...

http://www.phoronix.com/scan.php?page=news_item&px=AMDGPU-GFXOFF-Patches

[Nille_kungen]

Would this make it able to turn off the dGPU in an raven ridge APU based laptop or only the iGPU in the APU?
That would make the fans work a lot less and an laptop to be a lot more silent.

[Nuc!eoN]

Interesting, this seems to be an implementation of AMDs ZeroCore feature, which has been discontinued on Windows 10 and doesn't support connectors other than DVI. DP and HDMI are not supported because of the audio chip according to AMD (The Fury X seems to be an expeption there, since it even has a special LED for that very powerstate)

[Peter Fodrek]

It may be related to Epyc release slide showing GPU fore Epyc Socket as koprocessor or another processor in server
]https://diit.cz/sites/default/files/...?itok=UmCYXyFR

[Brisse]

Pretty sure my secondary R9 Fury shuts down and gets close to zero Watts in Windows, while in Debian both of them constantly idles at around 15W. Wonder if this is the same feature that already seems to be implemented in Windows.

[FireBurn]

Would this make it able to turn off the dGPU in an raven ridge APU based laptop or only the iGPU in the APU?
That would make the fans work a lot less and an laptop to be a lot more silent.

It already can do that, that's what PRIME does. When you're not using the card it's switched off entirely.

I do hope they bring that feature to regular desktops too, would be great for media PCs so you only fire up the graphics card when it's needed for say gaming but use the onboard graphics for decoding video

[Nille_kungen]

It already can do that, that's what PRIME does. When you're not using the card it's switched off entirely.

I do hope they bring that feature to regular desktops too, would be great for media PCs so you only fire up the graphics card when it's needed for say gaming but use the onboard graphics for decoding video

It doesn't work very well, when i had my laptop with 9830P and RX460 the fans drove me crazy and i rarely used DRI_PRIME=1.
I'm not quite sure that prime actually turns of the dGPU completely since the chip seems produce heat even when not used, sensors often reports temperatures above that of an turned of chip.

[FireBurn]

As someone who's had both a Radeon 6600M and M395X I can assure you that it does work well and it does turn off the chip, the sensors don't report anything when the chip if off

If you're seeing more heat when it's off then report a bug. If you don't have radeon or amdgpu loaded the card will still be powered waiting to be bound to a driver