Re: puc fails to attach serial ports

From: "David O'Brien" <obrien_at_freebsd.org>
Subject: Re: puc fails to attach serial ports
Date: Tue, 13 Dec 2005 09:00:15 -0800

> On Tue, Dec 13, 2005 at 11:01:42AM -0500, John Baldwin wrote:
> > Because sio(4) only includes sio_puc.c in the kernel if you have 'puc' in your 
> > kernel config, and the puc kernel module only includes the puc files, it 
> > doesn't include sio_puc.c and ppc_puc.c.  uart has the same issue as well.  
> > Looking at the three attachments, there's no reason for them to be dependent 
> > on puc, they don't actually call any symbols in the puc(4) kernel module 
> > itself, so they can be compiled into kernels w/o puc without causing any 
> > harm.  Then loading puc as a module would work.  Here's a patch:
> 
> Isn't there another way?  It just seems wrong to include *_puc bits in
> the kernel if you don't have 'puc' in your kernel.  There are some
> working on trimming down the kernel for embedded purposes and this patch
> seems counter to that effort.

puc certainly isn't unique.  pccard has exactly this same problem as
well.  However, with pccard, people rarely load it as a module.

In general, if you want full dynamic behavior, you have to load
everything as a module (this works very well, I do it for everything
except ata on my laptop).  If you want static behavior, you need to
build stuff statically.  If you want to cross threat the two, you
might run into problems like this.

Warner