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Draft: radv: Add a dedicated transfer-only queue using SDMA

Timur Kristóf requested to merge Venemo/mesa:radv_transfer_queue into main

This MR adds a transfer queue implementation to RADV, which uses the SDMA hardware to implement Vulkan transfer commands. Note, some discussion and background information about this feature can be found in issue #850. The new transfer queue implementation is currently hidden behind a perf test flag, and can be activated using RADV_PERFTEST=transfer_queue.

Based on

Hardware support

  • GFX9, GFX10, GFX10.3 and GFX11 should work fine now
  • GFX6-8 are currently out of scope

Implemented workarounds

  • Compression (DCC and HTILE) is disabled on transfer queue image layouts on GFX9 which doesn't support it and Navi 10 which is buggy
  • Copying between tiled images sometimes requires a scanline copy (which means copying the image in smaller chunks)
  • Copying between unaligned buffers and images sometimes requires a chunked copy too
  • Some images are unsupported by SDMA, such as mulisampled images (on all HW), sparse bindings (on GFX6-8) and emulated formats such as ETC2 and ASTC. When copying these images, use a gang submission and execute the copies on an async compute command buffer.


Vulkan CTS



mpv -v --vo=gpu-next --gpu-api=vulkan --vulkan-async-transfer=yes <filename>


DXVK is supposed to use transfer queues in some cases, but I haven't tested this yet.

Edited by Timur Kristóf

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