It appears that console_setup() code only gets compiled into the kernel if
CONFIG_PRINTK is enabled.  One detrimental side-effect of this is that
serial8250_console_setup() never gets invoked when CONFIG_PRINTK is not
set, resulting in baud rate not being read/parsed from command line (i.e.
console=ttyS0,115200n8 is ignored, at least the baud rate part...)

Attached patch moves console_setup() code from inside

#ifdef CONFIG_PRINTK

to outside (in printk.c), removing dependence on said config. option.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>