Re: [patch] early printk and boot console fixups.

[Bjorn Helgaas <bjorn.helgaas@hp.com>]

On Wednesday 16 May 2007 11:09:14 am Maciej W. Rozycki wrote:
> On Wed, 16 May 2007, Bjorn Helgaas wrote:
> 
> > > for early_uart_console, I have some ideas:
> > > 1. merged that into early_serial_console in
> > > arch/x86_64/kernel/early_printk.c, and
> > > move early_printk.c to kernel/, --- make it understand
> > >      earlyprintk=uart,io,0x3f8,9600n8
> > >      earlyprintk=uart,mmio,0xff5e0000,115200n8
> > > in addition to vga, ttyS, serial
> > 
> > I would rather try to merge 8250_early and early_printk.
> > "console=uart,io,0x3f8" is already pretty similar to
> > "earlyprintk=serial", and it would be nice to have only one.
> > 
> > "console=uart" does have the disadvantage that you have to know the
> > port address.  But it has the advantage that it doesn't depend on
> > compiled-in legacy serial port names.  If you need early console
> > output, you're probably a developer and can come up with the address.
> 
>  Given the generic name of "uart" I am assuming this will work with any 
> UART driver making use of the serial_core.c core -- am I correct?

I knew somebody would ask that eventually :-)

Unfortunately, the answer is "no."  "console=uart" only works with
8250-compatible devices.