Boot Loader Support for BinFS (Windows CE 5.0)
If a boot loader includes support for the binary ROM image file system (BinFS), the boot loader can partition, format, and write data to a specified media device. Through the Bootpart library, the boot loader writes to flash media. The boot loader uses the Bootpart library to create partitioning. This partitioning is necessary for both BinFS and another file system, such as FAT, to be flashed on the same media device. To accomplish partitioning, the boot loader uses the Bootpart library to create a BinFS partition along with an extended partition. The OS uses these partitions to create one or more data partitions inside of the extended partition. The extended partition is required because the OS cannot modify the master boot record (MBR) once the boot loader's Bootpart library partitions flash memory.
The Bootpart library can create a boot partition to store boot arguments. The flash memory blocks that contain the MBR sector, the BinFS memory region, and the boot arguments partition are marked as read-only. In addition, the BinFS and boot partitions are marked as read-only so that the partitions cannot be formatted or deleted.
Bootpart enables code for a Flash Media Driver (FMD) to be abstracted from the boot loader. The boot loader creates the partition and reads or writes to the partition by specifying a byte offset into the partition, as well as a length value. Bootpart can also perform a low level format on the flash media.
To support BinFS, your boot loader must link to the Bootpart library located in the %_WINCEROOT%\Public\Common\Oak\Drivers\EthDbg\Bootpart directory.
For more information on the Bootpart library see, Bootpart Library Functions. You can view a sample boot loader that supports BinFS in the %_WINCEROOT%\Platform\SMDK2410\Eboot directory.
See Also
Binary Rom Image File System (BinFS) | How to Implement BinFS | BinFS and the Bootpart Library | Bootpart Library Functions
Send Feedback on this topic to the authors