Julius Werner has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/37465 )
Change subject: arm64: Print a char to UART early in exception handler ......................................................................
Patch Set 2:
(1 comment)
https://review.coreboot.org/c/coreboot/+/37465/1/src/arch/arm64/armv8/except... File src/arch/arm64/armv8/exception.c:
https://review.coreboot.org/c/coreboot/+/37465/1/src/arch/arm64/armv8/except... PS1, Line 136: __uart_tx_byte
What if a board does not initialize UART, or even does not include UART drivers? […]
__uart_tx_byte() is defined to a no-op if serial drivers aren't configured in.
If the UART driver is configured in but hangs, then yeah, this will hang. But otherwise it would hang at the printk() below anyway.