You need at least kernel-4.15.xx.
Even better 4.18.xx
" CONFIG_DRM_AMD_DC: │
Choose this option if you want to use the new display engine │
support for AMDGPU. This adds support for Vega and │
Raven ASICs. │
Symbol: DRM_AMD_DC [= y] │
Type: bool │
Prompt: AMD DC - Enable new display engine │
Location: │
-> Device Drivers │
-> Graphics support │
-> Display Engine Configuration │
Defined at drivers / gpu / drm / amd / display / Kconfig: 4 │
Depends on: HAS_IOMEM [= y] && DRM "
Best regards
T.