The OSPI boot mode has an SPI compatible serial bus interface with extended octal commands. The OSPI boot mode supports an 8-bit data bus width and single data rate (SDR) during the RCU BootROM execution. The BootROM runs at an OSPI device clock frequency between 11 MHz and 24.5 MHz dependent on the REF_CLK clock input frequency. After the BootROM code execution, the PLM firmware can support the double data rate (DDR) with strobe for higher performance.
For additional information on the OSPI controller, see Octal SPI Flash Memory Controller. For details on OSPI flash device support, see the Vivado Design Suite User Guide: Programming and Debugging (UG908).
Note: The OSPI boot mode can be configured to a OSPI
single or dual-stacked setup. When using OSPI dual-stacked mode, the BootROM can
only access the lower OSPI0 addressable flash memory space for boot. After boot, the
PLM firmware can access the upper OSPI1 for additional image storage.