drm/vkms Virtual Kernel Modesetting

vkms is a software-only model of a kms driver that is useful for testing, or for running X (or similar) on headless machines and be able to still use the GPU. vkms aims to enable a virtual display without the need for a hardware display capability.



  • Optimize CRC computation compute_crc() and plane blending blend()
  • Use the alpha value to blend vaddr_src with vaddr_dst instead of overwriting it in blend().
  • Add igt test to check cleared alpha value for XRGB plane format.
  • Add igt test to check extreme alpha values i.e. fully opaque and fully transparent (intermediate values are affected by hw-specific rounding modes).