(Just posting the link to the relevant Wiki page, FYI.)
IPQ5xxx isn't a good start.
What is this
It have a Qualcomm cpu so what is the issue supporting this?.
That's the SoC.
Dunno, ask Qualcomm why they haven't added the support to the Linux kernel.
If you would have searched the forum, you would have found the same answer in Adding OpenWrt support for TP-Link RE700X, IPQ5018.