Yes. Attaching serial console is the first step to know what's going on.
If you don't get anywhere from there (because bootchain fails very early) you got two more options:
- directly connect to the SPI-NAND flash chip, e.g. using CH341 USB-SPI adapter (more complicated than one might think as you will have to imitate the in-hardware ECC OOB layout)
- connect JTAG pads e.g. to FTDI FT2232H breakout and use OpenOCD, see