[syslinux] non-standard (PCI) Serial port

[Jordan Hargrave]

I'm trying to get isolinux serial port working on a system.  Using
UEFI boot mode but system does not have Legacy Serial port (3f8, etc)
enabled.  Serial port devices are PCI devices, memory mapped I/O with
32-bit offset.  Using linux kernel command line
console=uart8250,mmio32,xxxx,115200n8 works.  However I do not see
syslinux/isolinux boot menu.

Looking through the code it looks like syslinux assumes serial ports
are I/O only and do not use EFI boot services Serial Port?