Why do I see problems accessing QSPI flash when using Intel® Stratix® 10 FPGA or Intel Agilex® 7 devices starting from Intel® Quartus® Prime Pro Edition Software versions 21.1 and 20.1, respectively?

Description

Starting from Intel® Quartus® Prime Pro Edition Software version 21.1 when using Intel® Stratix® 10 FPGA devices and version 20.1 when using Intel Agilex® 7 devices, QSPI access may fail if the QSPI_SET_CS command is not executed after the QSPI_OPEN command, when in Active Serial/QSPI mode.

In prior versions of Intel® Quartus Prime Pro Edition Software, the execution of QSPI_SET_CS after QSPI_OPEN was optional and not mandatory when in Active Serial/QSPI mode.

Resolution

This problem is fixed starting with the Intel® Quartus® Prime Pro Edition Software version 21.3.