The QSPI24 and QSPI32 boot modes support the following:
- x1, x2, and x4 read modes for single Quad SPI flash memory 24 (QSPI24) and single Quad SPI flash memory 32 (QSPI32)
- x8 read mode for dual QSPI.
- Image search for MultiBoot
- I/O mode for BSP drivers (no support in FSBL)
The bootROM searches the first 256 Mb in x8 mode. In QSPI24 and QSPI32 boot modes (where the QSPI24/32 device is < 128 Mb), to use MultiBoot, place the multiple images so that they fit in memory locations less than 128 Mb. The pin configuration for QSPI24 boot mode is 0x1.
Note: QSPI dual stacked (x8) boot is not supported. Only QSPI Single Transmission Rate (STR) is supported. Single Quad-SPI memory (x1, x2, and x4) is the only boot mode that supports execute-in-place (XIP).
To create a QSPI24/QSPI32 boot image, provide the following files to the Bootgen tool:
- An FSBL ELF
- A secondary boot loader (SBL), such as U-Boot, or a Cortex-R5F-0/R5-1 and/or a Cortex-A53 application ELF
- Authentication and encryption key (optional)
For more information on Authentication and Encryption, see Security Features.
Bootgen generates the boot.mcs and a boot.bin binary file that you can write into the QSPI flash using the flash writer. MCS is an Intel hex-formatted file that includes a checksum for reliability.
Note: The pin configuration for QSPI24 boot mode is 0x1 for qspi 24 and 0x2 for qspi32.