RE: [Linuxconsole-dev] writeup

[Brad D. <Br...@NE...>]

> -----Original Message-----
> From: James Simmons [mailto:jsi...@ac...]
> 
> > I guess a head could simply be defined as "A head is equal 
> to an active VT".
> > The definition of a head is implied by VT.
> 
> No. More than one VT can be on a head. I like the idea of VT 
> pools per 
> head. Why do I call it pools. Because I like to think of it 
> expandable 
> and shrinkable. Right now their is 32 VTs. With a multihead 
> system you 
> would have number of heads * 32 VTs. This can get quite 
> expensive. So you
> would start with one VT and if you VT switch grow a new VT. 
> So teh VT pool
> grows. Only one VT can be active per head. 

Yes, you're right.  At it's core, a head can have (theoretcally) an
unlimited number of VTs, but there will always be at least one.  That's why
I chose the wording I did.  Perhaps it is too vague.

> > My question didn't get answered, tho...  Or maybe I'm using 
> the wrong
> > definition of console:  Can there be two active consoles at 
> the same time
> > (in the instance of multi-head)?  When I ask this, I'm 
> thinking of say,
> > kernel message output to console.
> 
> I have though about that but have no answer. In a multihead 
> system where
> should printk go to. Any suggestion anyone ?

At the present, I suggest a master/slave[x] designation somewhere in fbdev
and have data destined for the console spew onto the master.  I'll talk with
Petr and ask for his input and experiences.  I'll move further discussion of
this thread to linux-fbdev, since it's really a fbdev issue.

Brad Douglas
br...@ne...
http://www.linux-fbdev.org