I tested this patch on a Late 2013 Mac Pro (MacPro6,1) with dual Apple FirePro D700 (Tahiti XT, 6 GB), and can confirm that it fixes the DPM issue on the D700 as well.
Test environment: Arch Linux Kernel: 6.18.54-1-lts + this patch Mesa/RADV: 26.2.3 GPU: 2x FirePro D700 (Tahiti XT, 6 GB) Params: radeon.si_support=0 amdgpu.si_support=1 Without the patch, both D700s remained at 300 MHz SCLK / 150 MHz MCLK under Vulkan compute load. I checked the D700 VBIOS as well: ATOM_PP_PLATFORM_CAP_HARDWAREDC is set, and it contains a battery state at 300/150 MHz. With the patch applied to the same kernel, each D700 correctly transitions from 300/150 MHz at idle to 850/1370 MHz under load. I tested both GPUs individually and simultaneously. As a real-world test, Ollama/Qwen3-8B fully offloaded across both GPUs sustained approximately 18.3-18.7 tokens/s, compared with ~2.34 tokens/s before the patch. One API run generated 1517 tokens in 81.24 seconds. I observed no amdgpu VM faults, GPU timeouts or resets during the tests. Tested-by: Mikael Pelle [email protected]
