Connectivity of multiple FPGA's and Serial PROM with single header

How you implement your configuration scheme depends on what you are trying to do.

For example, does your board have a controller processor or microcontroller? If it does, then simply have that processor configure all the FPGAs. Having FPGA images stored on separate SPI flash could make maintenance of your board difficult, eg., if the FPGAs need to communicate with each other, then its important that each FPGA have a valid image that does not cause driver conflicts with other FPGA images. If you have separate images, then you run the risk of someone not updating images correctly, and damaging the board. In that case, its "safer" to consider the configuration for all five FPGAs as a single image.

Take a look at this design;

https://www.ovro.caltech.edu/~dwh/carma_board/

The four FPGAs on that board are programmed by the PowerPC device. The fifth FPGA is a system controller that is configured from flash memory using a MAX II CPLD as a configuration controller.

Its takes under a second for the FPGAs to configure, so daisy chaining them does not really make much of a difference to the configuration time.

Provide more details on your board-level design and users of this forum can suggest improvements.

Cheers,

Dave