Re: OLS and console rearchitecture

[Jesse Barnes <jbarnes@engr.sgi.com>]

On Monday, August 2, 2004 7:24 am, Jon Smirl wrote:
> 1) PCI ROMs - these would be exposed via sysfs. A quirk is needed to
> track the boot video device and expose the contents of C000:0 for that
> special case. See the lkml thread: Exposing ROM's though sysfs, there
> are already proposed patches.

I just posted what I hope is a final patch for this one.  We'll see what 
gregkh comes back with.

> 2) VGA control - there needs to be a device for coordinating this. It
> would ensure that only a single VGA device gets enabled at a time. It
> would also adjust PCI bus routing as needed. It needs commands for
> disabling all VGA devices and then enabling a selected one. This device
> may need to coordinate with VGA console. You have to use this device
> even if you aren't using VGA console since it ensures that only a
> single VGA device gets enabled.
> Alan Cox: what about hardware that supports multiple vga routers? do we
> care?
> JS: no design work has been done for this device, what would be it's
> major/minor? would this be better done in sysfs?

It should probably be a real device driver rather than a sysfs pseudofile.  
Not sure if it should be dynamic or not though.  It would be nice if apps 
used the driver to do legacy VGA I/O port accesses as well, since that would 
make things easier on platforms that unconditionally master abort when a PIO 
times out, and would probably make it easier to deal with multiple domains.

Jesse