Re: [coreboot] [Qemu-devel] Release plan for 0.12.0

[Anthony Liguori]

Patrick Georgi wrote:
> Am Sonntag, den 04.10.2009, 14:31 -0500 schrieb Anthony Liguori:
>   
> > I don't know enough about EFI, but my concern is that down the road, 
> > hardware devices will start to exist that require EFI because they 
> > implement EFI modules and not legacy option ROMs.  In order to support 
> > PCI passthrough of such devices, we will need to provide an EFI capable 
> > firmware.
> >     
> Why? They're initialized at boot time (by the host's EFI firmware, if
> necessary), and are usable by the OS then.
>   

EFI defines new interfaces for OSes to use.  A device is going to want 
to provide drivers for those new interfaces.

For instance, EFI defines a SCSI passthrough protocol such that a RAID 
controller could install an EFI SCSI driver and that would allow OSes to 
install to it without requiring special drivers.  Of course, I'm sure 
we'll still see special drivers.

I assume that future RAID controllers will provide both a legacy option 
ROM (int13 hook) and an EFI SCSI driver.  However, I'm also pretty sure 
that we'll see some subset of devices that only provide the EFI modules 
because they target a very specific class of hardware/software that will 
be EFI enabled.

> Beyond boot loaders and toy kernels, firmware level drivers hurt more
> than they help. The world changed since the invention of BIOS in CP/M.
>   

Except that VESA and VGA are still pretty popular.  It's not at all 
uncommon to either use a VESA driver or at least to complete an install 
with just a VESA driver.

--
Regards,

Anthony Liguori