On Tue, 17 Jun 2003, Ladislav Michl wrote:
> Idea is to have only one way for printing kernel messages. In case of Indy,
> O2 and SNI RM200 "arc" console will do it. Here you can find where should
> be early console initialized:
> http://marc.theaimsgroup.com/?l=linux-kernel&m=105519188505235&w=2
> As Juan pointed out setup for such console is actually a nop and one is
> supposed to enable this feature only when debugging kernel. DEC prom console
That's a valid point, as long as enabling it does not require a
reconfiguration.
> however needs some setup to determine REX entry points. early console is
> currently used on sh, alpha, x86_64 and ia64 architectures. Btw, see comment
> at the top of arch/sparc/prom/printf.c
The DEC's entry points are a part of the problem only -- to support a
generic kernel, we need to move early_printk setup after setup_arch(), as
the level of variation is huge then..
There is also that minor implementation problem -- how to pass varargs
from printk() to ROM's printf()? At least the firmware of the DECstation
implements a full-featured printf() as in the C library.
--
+ Maciej W. Rozycki, Technical University of Gdansk, Poland +
+--------------------------------------------------------------+
+ e-mail: macro@ds2.pg.gda.pl, PGP key available +
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