Those sound an awful lot like IAR specific functions. Sounds like you have some porting work to be done to convert from IAR to GCC
Full Duplex SW-UART with FIFO:
Wrote a naive implementation that's probably a good starting point. Check it at my blog http://electronic-excursions.blogspot.com. It's a good place to start and pretty easy code to decipher. TX is done too and will be posted soon.
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