earlyprintk= [X86,SH,BLACKFIN,ARM]
earlyprintk=vga
+ earlyprintk=efi
earlyprintk=xen
earlyprintk=serial[,ttySn[,baudrate]]
earlyprintk=serial[,0x...[,baudrate]]
Append ",keep" to not disable it when the real console
takes over.
- Only vga or serial or usb debug port at a time.
+ Only one of vga, efi, serial, or usb debug port can
+ be used at a time.
Currently only ttyS0 and ttyS1 may be specified by
name. Other I/O ports may be explicitly specified
Interaction with the standard serial driver is not
very good.
- The VGA output is eventually overwritten by the real
- console.
+ The VGA and EFI output is eventually overwritten by
+ the real console.
The xen output can only be used by Xen PV guests.