SPRZ452I july 2018 – may 2023 AM6526 , AM6528 , AM6546 , AM6548
Boot, UART: UART Boot Mode Never Times Out
AM65x SR 1.0
When UART is configured as the primary boot mode and its 180-second timeout expires, the ROM code is expected to switch to the selected backup boot mode. However, this transition to the backup boot mode never occurs.
Instead, the SoC device goes through a warm reset because the watchdog timer expires before the UART boot mode times out. After the warm reset, the SoC device will continue to attempt booting from UART, instead of switching to the backup boot mode.
Do not select a backup boot mode when UART is the primary boot mode.