My basic thinking was to boot Armbian from the SD card and then use "dd" to place the SPL and uboot onto the emmc. I can use "scp" to copy the U-boot image from my desktop to Armbian, then I do commands like this:
dd if=/dev/mmcblk1 of=save.bin bs=1024 count=1024 dd if=u-boot-sunxi-with-spl.bin of=/dev/mmcblk1 bs=1024 seek=8Just as a note; the emmc as shipped has android installed with a bizarre partitioning scheme. I suppose the disk could be repartitioned, but I don't see a real problem for just leaving it as it is and doing the above. I'll ignore the details here, except to say there is a big extended partition starting at sector 1, but it is largely empty, the first partition inside of it begins at sector 73728. The U-boot with spl image is about 458K in size (so it requires about 1000 sectors).
When I halt Armbian, remove the SD card, and reboot, I get this:
U-Boot SPL 2016.11-g29e0cfb-dirty (Dec 18 2016 - 15:32:55) DRAM: 1024 MiB Trying to boot from MMC2 MMC Device 1 not found spl: could not find mmc device. error: -19 SPL: failed to boot from all boot devices ### ERROR ### Please RESET the board ###So .... the SPL is unable to locate the MMC device. This build of U-boot is for the Orange Pi PC and works fine when booting from SD card.
Tom's electronics pages / tom@mmto.org