[LinuxBIOS] v3: documentation fixes

Carl-Daniel Hailfinger c-d.hailfinger.devel.2006 at gmx.net
Thu Nov 15 11:45:02 CET 2007


On 15.11.2007 01:32, Jordan Crouse wrote:
> I think printk is always available - any previous printk pain has been
> (finally) resolved.
>   

That warrants updating the design doc as well as another question: Is
printk available before early serial port setup? AFAICS it is not. We
have to differentiate between 4 stages (not in our stage sense) for printk:
1. No CAR, no RAM, no early serial - > printk is not feasible
2. CAR, but no RAM, no early serial -> printk to an internal buffer
could work, but the user can't see that
3. CAR, early serial, but no RAM -> printk to serial works
4. (much later) RAM, serial, VGA -> printk to serial and VGA works

When do we want to declare printk as usable?

Regards,
Carl-Daniel




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