Just flashed an u-bbot version from here which does support NVMe...well at least it recognizes the SSD (o;
https://github.com/cubie-image/sun55iw3p1/releases
=> pci enum
Speed change timeout
PCIe speed of Gen1
=> nvme scan
feng >>>> debug <<<<< nvme_probe
=> nvme device
IDE device 0: Vendor: 0x1dee Rev: 1.4.7.70 Prod: 2510194702629
Type: Hard Disk
Capacity: 488386.3 MB = 476.9 GB (1000215216 x 512)