Supporting extension ROMs and beyond...

[Eric W. Biederman]

ron minnich <rminnich at lanl.gov> writes:

> On Sat, 9 Aug 2003, SONE Takeshi wrote:
> 
> > Then it's convenient to have a few more INTs and generic PCI ROM
> > enabling routine to enable the SCSI adapter. That code would be
> > simple and small anyway.
> 
> It doesn't bother me. I am fine with it. I believe that the VGA BIOS 
> support can be used for this as well, with very little extra work.

Several bugs fixes later and we have put the Bochs BIOS into LinuxBIOS.
Which doesn't work on anything but x86....

> > Then, at this point, why not adding a simple code to load IPL and
> > jumping it in real mode? It's smaller than a printk.
> 
> Sure. 
> 
> Eric is concerned that it not be in the "core". 

I am concerned in large part with feature creep and future maintainability.
I drew a line in the sand so we can see when we are going over it and
are close to being in trouble.

In the core we don't drive the hardware we initialize the hardware.  We only
drive the hardware that is needed to initialize other parts.

> I am willing to call it a 
> compiled-in extension if everyone is ok with that. We could have a 
> src/extensions directory, and put items such as the VGA BIOS support etc. 
> in there. Such extensions have to be explicitly enabled. The static device 
> mechanism gives us an easy way to hook into them.

It might be possible to convince me.  But doing it because it is most
convenient this way is not one I like.

> But for reasons of space at least, I would really like to keep the ability
> to compile VGA BIOS support directly into linuxbios. The ELF chaining that
> Adam mentioned, while interesting, is complex enough to worry me.

And why can't you do this a kernel patch for your magic kernel bootloader?

> Takeshi did I apply your last patch to VGA BIOS support? Can you check? 

Eric