AMD Linux Graphics Driver Now Allows Display Support With Modern GPUs On LoongArch

Following the Linux 6.13 DRM feature pull this week that brought many new open-source kernel graphics driver features, it's now time to further stabilize that new feature code with fixes. Sent out today were a batch of fixes for the AMDGPU/AMDKFD kernel driver code targeting the early Linux 6.13 state. In addition to fixes though is also allowing the AMDGPU Display Core "DC" code to build properly on LoongArch hardware for allowing recent AMD Radeon GPUs to work on these Chinese systems.

Similar to the change made to the AMDGPU driver several months back for DC display support on RISC-V hardware to be able to drive monitors on RISC-V systems with recent generations of Radeon GPUs, the AMDGPU driver now allows for DC use on LoongArch hardware.

This LoongArch AMDGPU DC support wasn't authored by AMD engineers but rather an open-source contribution from Loongson. Loongson engineer Huacai Chen commented on the patch just needing adjustments to the Kconfig:

"Clang on LoongArch (18+) appears to be unaffected by the bug causing excessive stack usage in calculate_bandwidth(). But when building DC_FP support the stack frame size can be as large as 2816 bytes, which causes the FRAME_WARN build warnings. So on LoongArch we allow building DC with clang, but disable DC_FP by default."

So for those wanting to drive a display on LoongArch hardware with an AMD Radeon GPU going back to the Vega days with the DC display engine, this support for compiling the DC code on LoongArch is on its way to the mainline kernel.

The patch is part of this AMDGPU fixes pull that in turn should be appearing in the mainline Linux 6.13 kernel in the coming days.