@Dalibor Pospíšil I haven't tested if the pcie works, maybe others did? But it's a bsp driver so it should. If that works, and if the SATA device has a driver in Linux 6.18, simply enable it in menuconfig and you should be good to go. EDIT: Right, I don't have A7A so I didn't really touch the dts for A7A, there might be a little works needed for it to boot.

@alexc What about SATA support? The a7a board has m.2 pcie where the PentaHAT can be attached (I tested it with a custom sunxi kernel).

IMHO, OP wants to boot OS from NVME while the firmware is stored in the SPI flash, but he is using firmware in which the necessary support is not enabled.

@eli I think I’ve got KVM enabled, but as they discussed previously, it's not a Linux kernel issue, there's some specific u-boot firmware needed. Since I don't think the open source firmware is ready yet, I guess KVM likely is not feasible on A733 for now.

What happens after that? Do you see PCIe getting activated? Is the NVME SSD enumerated? What brand and type of NVME?