Hi Arjun
Regarding your question : "why we are using the
byte swap rcw to boot the ls1021a iot (rev 1, rev b) using QSPI",
please take a look at the Application Note : AN4893.
It gives a good overview of endian differences on this
SoC. QSPI endianness requires the swap. As for not
able to boot, there was an erratum on booting from QSPI
on rev 1. You might want to review the errata list for rev 1
and see if it applies to your board.
Regards
Sinan Akman