On 10/12/2017 12:29 AM, Itaru Kitayama wrote: > Vadim, > > At this moment, I don't need to try to this specific latest CentOS kernel as I said > in previous replied to Jim, v4.13 boots on the HW, but thanks for your suggestion. > I've been booting up the HW with slightly at different address like below: > > earlycon=pl011,0x87e025000000 > > this give me lots of boot messages. Can you provide those messages? (btw if you have a correctly working firmware, simply saying "earlycon" will setup earlycon automatically) Usually the lack of any output is caused by something failing prior to the serial console being setup correctly. That specific Gigabyte platform has various firmware releases, of which you should be running the latest version to have the necessary ACPI tables. A quick note, on ACPI. Disabling ACPI is not an optional thing. If you turn it off, you will have a non-standard, completely untested, broken, non-functional machine. Nobody tests any of the kernel sources with ACPI disabled. In the future it won't be possible to disable it. Just say no to turning off ACPI. Jon.