OpenSystemsDevelopment / usbboot

Create a new rpiboot mode that uses a Linux initramfs to
implement mass-storage-gadget mode supporting EMMC and NVMe
block devices.

To use:
cd usbboot/mass-storage/gadget
../rpiboot -d .

Replace the example boot.img with a slightly more useful version
64-bit version that boots to a minimal busybox initrd with
USB enabled.

See https://github.com/raspberrypi/usbboot/issues/116

Fix help -c and -i default option

pieeprom-2022-02-08: Fix boot failure in locked secure-boot

The previous version would fail to boot if secure-boot mode was
locked via OTP settings.

recovery.bin prevent revoke_devkey from being set before the
customer key has been programmed.

Update bootloader to the latest stable release and use full SDRAM init in MSD / RAMDISK mode.

For test/debug purposes it's sometimes useful to erase the SPI
EEPROM using a chip-erase command. This has been available via
recovery.bin for a while but add it here for convenience.

The MSD (and secure-boot variant) bootloader has been updated to
fully initialise SDRAM in order to resolve problems when using
this method to run Linux ramdisks / initrd.
Therefore, MSD boot will not work on a system with a blank or
corrupted EEPROM. If so, an error message will be output to the
UART and the EEPROM should be programmed using the recovery
option.

e.g. previously, ../../filename would generate ../.sig

Previously, relative paths would confuse the file name generation regex.
With this change, only the final '.' character is matched as the
beginning of the file extension.

20220111~130126 release

rpiboot: Add build date and version

Capture the changelog version and git version (if available)

bootloader: Enable revoke_devkey in secure-boot recovery.bin

Enable the recovery config.txt options to revoke the ROM
development key which permentantely locks the device into
secure-boot mode.

WARNING: This also prevents the bootloader from being downgraded
to older releases which don't support secure-boot.

This is a very old test image and shouldn't be in this repo.
Since it's bit rotted remove it to avoid confusion.

The image should probably be published via a different repo.

Update the default EEPROM image to 2021-12-02

See: https://github.com/raspberrypi/usbboot/issues/102

Signed-off-by: Phil Elwell <phil@raspberrypi.com>

All the bootloader changes to support secure boot are now in the
stable EEPROM release so switch to that.

Update default pieeprom.bin to the rpi-eeprom stable release

Fix some minor shellcheck warnings

Delete the target file before attempting to replace it, sync before
unmount and set the ownership to be that of the sudo user and not
just root.

secure-boot: Add more documentation about the RSA signatures and add an optional public key argument