it largely depends on what 'linux' you are referring to here.
if you use a recent mainline kernel.org , wl127x is there, it just
need to be added in the kernel config. the wlan firmware are also
available in linux-firmware package that you can install in ubuntu.
for a minimal system, i recommend using these instructions
http://omapedia.org/wiki/OMAP_Ubuntu_Core
if you don't want to mess up with kernel/bootloaders, use the proposed
prebuilt, otherwise follow these instructions to rebuild from
'mainline'.