Primary and backup boot versions of tiboot3.bin differ slightly in where bootapp binaries are located. To verify the redundant boot mechanism, unique log messages are inserted into each version of tiboot3.bin to distinguish between primary and backup boot modes.

The system boots from the primary boot mode on the eMMC boot partition as shown in these sample log outputs.

SBL Revision: 01.00.10.01 (Jun 9 2024 - 13:16:51) from eMMC boot partition #1
TIFS ver: 9.2.4--v09.02.04 (Kool Koala)Starting Sciserver..... PASSED
 BOOT_APP (Jun 9 2024 - 13:16:54) from eMMC boot partition #1 in boot_app_main.c
MCU R5F App started at 7539 usecs
Loading BootImage
:

To simulate a failure and trigger the redundant boot, use the following commands to corrupt the tiboot3.bin in the eMMC boot partition:

mmc dev 0 1
mmc partconf 0 1 1 1
mmc bootbus 0 2 0 0
mw ${loadaddr} 0x00 0x1000
mmc write ${loadaddr} 0x0 0x400

After rebooting the system, the ROM code detects the corrupted primary image and automatically switches to the backup boot mode. This behavior can be confirmed through the unique log output associated with the backup tiboot3.bin.

SBL Revision: 01.00.10.01 (Jun 9 2024 - 13:46:16) from eMMC UDA partition
TIFS ver: 9.2.4--v09.02.04 (Kool Koala)Starting Sciserver..... PASSED
BOOT_APP (Jun 9 2024 - 13:46:18) from eMMC UDA partition in boot_app_main.c
MCU R5F App started at 7193 usecs
Loading BootImage
: