Details:

JEDEC spec JESD216 - SERIAL FLASH DISCOVERABLE PARAMETERS (SFDP) details the parameter table used in certain serial flash devices to describe features and how to communicate/configure the device. The ROM interprets relevant portions of the SFDP for a device's features (such as a how to change from 1S-1S-1S to 8D-8D-8D mode), but does not properly comprehend a flash device that requires:

• A swapped byte order in 8D-8D-8D mode compared to 1S-1S-1S mode
• A command extension that in 8D-8D-8D mode that requires a different command than the first byte sent (such as an inversion of the opcode or another unique byte)

Workaround(s):

Review the SFDP table of any candidate flash memory that is compliant with JEDEC JESD216; in most cases vendors do not publish this table and can instead be requested from the flash vendor. If the 18th DWORD of the JEDEC Basic Flash Parameter table has bit 31 with a value of "1b", then the memory must be programmed with a swapped byte order from the factory or programmed with the SoC. If bits [30:29] have a value other than "00b" then it will not work with any bootmodes in 8D-8D-8D mode. Avoid using any 8D-8D-8D bootmodes with that flash device as a result.