How can I access my SPI Flash after configuration for data storage in a Virtex-5 FPGA design?
The D_IN and CCLK are dedicated configuration pins, so what should be used to access custom data of my SPI memory?
Unlike the Spartan-3E/-3A/-3AN/-3A DSP devices, CCLK and D_IN for Virtex-5 FPGAs are dedicated configuration pins and cannot be assigned as user I/O in a design post configuration. It is possible to use the STARTUP_VIRTEX5 primitive to access the dedicated D_IN and CCLK from user logic post configuration. The USRCCLK0 input of the primitive will drive CCLK externally and the DINSPI output of the primitive will gather all data internally, coming from the Flash.
The STARTUP_VIRTEX5 primitive is documented in the Virtex-5 FPGA Configuration User Guide (UG191) -> Chapter 4: User Primitives -> STARTUP_VIRTEX5, accessible at:
Information on instantiating this primitive can be found in the Virtex-5 Libraries Guide for HDL Designs, accessible at:
http://www.xilinx.com/support/documentation/index.htm-> Design Tools Tab
PROMGen in iMPACT can be used to create the custom MCS file containing configuration and user data. This can be done with the -data_file switch.