root@debian ~ # dmesg |grep -i tty
[    0.000000] Kernel command line: console=ttyS1 115200 root=/dev/mmcblk0p2 rootwait loglevel=8 panic=10
[    0.459971] sunxi-uart.1: ttyS0 at MMIO 0x1c28400 (irq = 2) is a U6_16550A