An Ubuntu/Debian Kernel To Play With AMDGPU's OverDrive Overclocking Support

Friday was a big day for AMD's open-source team as beyond publishing experimental Southern Islands / GCN 1.0 support for AMDGPU they also published for the first time open-source OverDrive overclocking support for the AMDGPU DRM kernel driver.

I'm currently in the process of testing this OverDrive support in AMDGPU on Tonga and Fiji and expect to have that article up in the next day or two. Due to timing, the OverDrive support isn't going to be in the Linux 4.7 kernel but will be held off as material for Linux 4.8.

If you are interested in trying out the OverDrive support, which is limited to supporting Tonga / Fiji / Polaris, I've uploaded my (Ubuntu/Debian) test kernel for your easy kernel upgrading experience. Rather than applying the patches on top of DRM-Next-4.7, I opted to just build the drm-next-4.8-wip branch. This is early material for Linux 4.8 Radeon/AMDGPU and already has in the OverDrive patches.

As mentioned in the earlier article, this AMDGPU OverDrive implementation allows overclocking the GPU core between 0 and 20% with 1% steppings. This is controlled via the pp_sclk_od sysfs interface inside the DRM area (for most people, /sys/class/drm/card0/device/pp_sclk_od). For Phoronix Test Suite Git users is also support for reading AMDGPU OverDrive and displaying the overclock percentage on the PTS system table when overclocked.

Stay tuned for my open-source AMD OverDrive tests in the next day or two while if you want to try out the Linux 4.8 WIP code with OD support, download the kernel from Phoronix.net: linux-image-4.6.0-rc7-phx-drm-next-4.8-wip-od_4.6.0-rc7-phx-drm-next-4.8-wip-od-1_amd64.deb.