just a note: I was able to enable PCIe TPU via VM by enabeling the IOMMU in GRUB in pve shell
nano /etc/default/grub
for intel:
add
GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_iommu=on"
GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_iommu=on iommu=pt"
save
update-grub
nano /etc/modules
ad modules
vfio...