This is more of an fyi if you want to connect an NVME SSD drive to the J721 EVM.
The drive i bought is
once you get the drive the connector for the NVMe is on the back of the J721 evm. Once you connect the drive to the J721 board, then use SDK 7.3 to boot the board.
Once you get the linux prompt make sure that you have the nvme in your /dev directory. below is what it should look like
if yes then it is all set but you just need to format it so you can use it. below are the commands to format the drive and mount it
root@j7-evm:/# mkfs.ext4 /dev/nvme0n1
root@j7-evm:/# mount /dev/nvme0n1 /home/root/test/
Also in the sdk it talks about the lspci -vv, this command is not in the /bin but you need to run it as /usr/sbin/lspci -vv then it will work as defined in the sdk docs.
i hope this helps you to install the nvme ssd drive.