I got the info from my .config that UART on this board are 8250 memory mapped UART instead of typical IO mapped. Looks like grub2 does not support memory mapped UART.
On Wed, Mar 1, 2017 at 8:51 AM, Gailu Singh gailu96@gmail.com wrote:
Hi Experts,
Are UARTs available on Apollo Lake different than traditional 8250 UART? Or any specific settings (jumper etc) required to use them?
Problem Statement: I am using UART available (through micro USB port) on Leafhill CRB. I am able to get coreboot logs but grub fails to detect these uart.
I have following in my grub2.cfg serial --speed=115200 --unit=0 --word=8 --parity=no --stop=1
Grub output an error serial port COM0 not found
If I change --unit=0 to 1 or 2 grub2 reports similar error
serial port COM1 not found serial port COM2 not found