AR# 52660: 2012.3 - QSPI PROM files created from Vivado bitstreams fails to program FPGA
2012.3 - QSPI PROM files created from Vivado bitstreams fails to program FPGA
When creating a bitstream in Vivado targeting a QSPI, the documented constraint set_property BITSTREAM.CONFIG.SPI_BUSWIDTH 4 [current_design] is used.
For Vivado and ISE, the default OPCODE when using this option should be 0x6B, Fast Quad Read. This is the default in Xilinx ISE 14.3, but in Vivado 2012.2 and 2012.3, the PROM does not receive the require opcode of 0x6B needed for Fast Quad Reads.
To resolve this issue, the following constraint must be added: