SPI TXINTFLG set as soon as ENABLE is set

I have an OMAP-L138 and am accessing the SPI peripheral from the TMS320C740x core.

During initialization after powerup, I set the ENABLE bit in SPIGCR1 (i.e. cause it to make a 0->1 transition). I immediately see a 0->1 transition on the TXINTFLG bit of the SPIFLG register.

Is this the expected behavior of the TXINTFLG bit? It makes sense that it could be, because this bit indicates that it is possible to write a value to the SPIDATx register, but the manual (SPRUH77A) does not mention that TXINTFLG goes to 1 when ENABLE is set.

Regards, John Jenks