mb/ti/beaglebone: Load romstage/ramstage from SD

Adds a "sd_media" boot_device to allow booting from the SD card. This
assumes that the generated "MLO" file is placed at a 128KB offset from
the start of the SD card, to allow for the MBR etc. to be at the start
of the SD card. Placing the MLO file here allows the AM335x boot ROM to
load and execute the bootblock stage as well, as 128KB is one of the
offsets the boot ROM checks when looking for the next stage to execute.

As part of this, a FMD for the Beaglebone has also been defined. It's
sized at 32M somewhat arbitrarily, as SD cards could allow for much
bigger payloads.

TEST: Beaglebone boots from bootblock into romstage. Romstage to
ramstage still doesn't work as it needs RAM initialization first.

Change-Id: I5f6901217fb974808e84aeb679af2f47eeae30fd
Signed-off-by: Sam Lewis <sam.vr.lewis@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/44385
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

0 files changed, 0 insertions, 0 deletions