It's correct vfio configuration for GPU Passthrough, you will need to change ids to your GPU pci slot.
sudo apt-get install qemu-kvm qemu virt-manager virt-viewer libvirt-daemon-system libvirt-clients bridge-utils
dmesg | grep IOMMU
lspci -nn | grep -iP "VGA|audio"
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash amd_iommu=pt vfio-pci.ids=1002:66af,1002:ab20"
update grub reboot!
softdep amdgpu pre: vfio vfio_pci
vfio
vfio_iommu_type1
vfio_virqfd
vfio_pci
vfio
vfio_iommu_type1
vfio_pci
update initramfs reboot!
lspci -vnn | grep -iP "vga|amdgpu|nvidia|nouveau|vfio-pci|audio"