The following apply to all or multiple boot
modes that are QSPI related.
Note: When using a QSPI\SPI flash device
greater than 128 Mb, a flash device package with a RESET signal must be used. The reason is
that the ROM only uses 3 byte addressing mode (address is 24-bits). To address the full
memory address range, software will typically switch to 4-byte addressing mode. If a reset
to the processor occurs (eg, due to a warm reset), the ROM will execute expecting 3-byte
addressing mode, but the flash will have been left in 4-byte addressing mode. In order for
the flash device to return to 3-byte addressing mode, it must be reset using this signal.
This typically can be achieved by using the RESET signal on the flash memory device. ROM
code does not issue a software reset command.
Refer to the AM263x QSPI Flash Selection
Guide for additional details.