Hi all, We are using BMC Aspeed AST-2500 in our motherboard with OpenBMC firmware. 'obmc-console' is used to get host messages over BMC. obmc-console.conf looks like *lpc-address = 0x3f8sirq = 4local-tty = ttyS4local-tty-baud = 115200* BIOS serial redirection is enabled over COM port 0 (*0x3f8, sirq=4, baudrate=115200*) for super-IO. we set */dev/ttyS0* in CentOS to work in polling mode by making its *irq=0* using the following command $ setserial /dev/ttyS0 uart 16550a irq 0 Now we are getting CentOS login prompt on SOL. When we change /dev/ttyS0 back to interrupt mode with irq=4, we are not getting login prompt on SOL. Whether anything is required to be done in OpenBMC firmware/BIOS to enable irq mode for SOL ? Thanks, Akash