7I90 spi vs ethernet cards

Trying to figure out a couple things here. I'm thinking about using the 7i90 as sort of a swiss army knife and pumping a new bitfile into it for specific hardware attached to it when necessary.

I haven't messed with any of the SPI cards yet, only the ethernet cards. I have some projects I want to get going with some ARM boards (yeah I know) and I don't like tying up the single ethernet port, almost everything including some x86 SBCs have an SPI interface on the GPIO that's otherwise not doing anything.

So the question is, what is the performance difference between the ethernet interface and the SPI interface and is it major? In the case of using a raspberry pi, I would assume that the hm2_rpspi hal driver will work with a 7i90 as well but in the case that it's not a raspberry pi, how much of a performance difference should I expect using hm2_spi over hm2_rpspi and how much of a PIA is it to get spi anything working on a random ARM SBC?

The main issue with the generic spi driver (hm2_spi) is that it uses the
OS SPI device. Unfortunately these often have poor real time characteristics
so its hit-or-miss if the SPI driver for particular hardware will be usable or not...

( that's one of the the reasons for the hardware specific hm2_rpspi driver)

Well best case scenario, what does the hm2_rpspi driver look like against hm2_eth and does it work with the 7i90?

Probably a bit slower, And yes it will work with the 7I90

Is there any source or description for the specific bitfiles for the 7i90? There are plenty of bitfiles in the zip but I only see 1 source pinfile that is setup as generic gpio on all pins. Is there any way to find out how the compiled bitfiles have the pins arranged?

Any of the 72 pin pinout source files can be used with the 7i90
Typically the bitfiles have a similar name to the pinout source file

You can also read out the pin connections with mesaflash