Flash FAT file system to eMMC for Booting

[PeterT]

I understand the requirements to boot from SDMMC (FAT FS on first user partition with BOOT.BIN), but how can I set up that FAT file system on an eMMC device? Is there perhaps a tool to create a binary from a FAT FS (I know of a tool to do this with an EXT2 FS) then use SAM-BA to flash the binary to the eMMC?

[blue_z]

I understand the requirements to boot from SDMMC (FAT FS on first user partition with BOOT.BIN), but how can I set up that FAT file system on an eMMC device?

Since AT91Bootstrap seems to treat the eMMC as a SDcard, there is no "user partition".
You would need to treat the device as a MS-DOS mass-storage device with a MBR/partition-table in the first sector, and a VFAT filesystem in the first primary partition.

If you build and then boot from a SDcard a Linux system with an initramfs, then you could use any Linux tool you want.

Regards

[PeterT]

So is it not possible to make the eMMC bootable without using an SD card for the first bringup?

[blue_z]

So is it not possible to make the eMMC bootable without using an SD card for the first bringup?

I didn't write anything close to that.

[PeterT]

I obviously failed to properly specify that in my question. I'm thinking about when my design reaches production and wondering if I can accomplish the first bring-up by flashing the FAT FS containing BOOT.BIN directly to the eMMC with SAM-BA through USB instead of relying on an SD card.

[blue_z]

I'm thinking about when my design reaches production and wondering if I can accomplish the first bring-up by flashing the FAT FS containing BOOT.BIN directly to the eMMC with SAM-BA through USB instead of relying on an SD card.

Writing the filesystem makes no sense without writing a MBR partition table.
You need an image file that begins with the first sector of the device rather than the first sector of the partition/filesystem.
Build that image using Linux tools by booting from SDcard.

IMO SAM-BA is (typically) useless with non-Atmel eval boards. "Production" boards rarely have CS jumpers/switches that allow reliable execution of the SAM-BA Monitor, although some of the latest SoCs now have a boot configuration register.

Regards