SPI interface for ICSP. does it matter which one?

I am creating a board to do some testing on an ATxmega128A3U. I've thoroughly read the datasheet and see it only references using JTAG or PDI to send programs. First question; is it possible to program this chip using SPI like a 328p? Also, many of these chips have multiple SPI interfaces. do they accept data from any SPI when in programming mode? I never see a reference on forums to which SPI is being used.

The ATXMegas need to be programmed via JTAG or PDI, they can't be programmed via ISP. It is possible to use a USBASP with modified firmware to program them.