GD55 NOR Flash

NuttX provides support for QSPI based NOR flashes from GigaDevices GD55 family. The supported capacity is up to 2 Gbit (256 MB).

The driver is enabled by option CONFIG_MTD_GD55. It is possible to select the QSPI mode with CONFIG_GD55_QSPIMODE option and communication frequency with CONFIG_GD55_QSPI_FREQUENCY option.

The flash allows to simulate 512-byte large erase blocks if option CONFIG_GD55_SECTOR512 is enabled. This is used to map the native 256 byte sectors to 512 byte sectors. It is useful if using a file system that demands 512 byte sectors, such as FAT.

The size of the flash is set automatically during the device initialization.

The flash memory has to be initialized before used. This is typically done from board support package layer during the board’s bringup phase. This operation is performed by following function.

#include <nuttx/mtd/mtd.h>

FAR struct mtd_dev_s *gd55_initialize(FAR struct qspi_dev_s *qspi,
                                      bool unprotect)