1.1.1.5 MPU Bootloader memory layout

MPU Bootloader persistent storage layout

For SD/eMMC media

  • The SD/eMMC media uses FAT-FS file system to store the Bootloader, Application and AT91bootstrap images.

For NAND/Serial Flash media

The placement of the AT91bootstrap, Bootloader and the application in flash memory should be such that the application will not overwrite the Bootloader/AT91bootstrap, and the Bootloader can properly program the application when it is downloaded.

  • The application code can be placed anywhere after the bootloader end address. The application start address should be aligned to Erase Unit Size of the device

  • As the Bootloader code requires the application start address to be mentioned at compile time, it should match in both the application and bootloader

  • The size of application image stores into Metadata region (address : 0x00180000) in the Flash memory

MPU_bootloader_persistent_storage_layout

MPU Bootloader execution memory layout

  • The following table shows Bootloader and Application start address in DDR memory for all MPU devices

DevicesBootloaderApplication
SAMA5D20x26F000000x21000000
SAM9X600x23F000000x21000000
SAM9X70x23F000000x21000000
SAMA7G50x66F000000x61000000

For example, SAMA5D2 DDR execution memory layout is shown in the diagram as below

MPU_bootloader_execution_memory_layout