Your environment variable "mainlineLinux" is wrong and "arcNumber" is not even set. in order to run non stock kernel you need to have both set.
your "mainlineLinux need to chage to "yes" and arcNumber to "2097".
since your said you use "ext2ls mmc 0:2" to see your rootfs then your bootargs need to change to console=ttyS0,115200 root=/dev/mmcblk0p2 rootdelay=5, so basically
Code:
Marvell>> setenv mainlineLinux yes
Marvell>> setenv arcNumber 2097
Marvell>> setenv bootargs_root root=/dev/mmcblk0p2 rootdelay=5
Marvell>> saveenv
Marvell>> reset
Marvell>> setenv arcNumber 2097
Marvell>> setenv bootargs_root root=/dev/mmcblk0p2 rootdelay=5
Marvell>> saveenv
Marvell>> reset
Good luck






