Re: [Qemu-devel] [PATCH 3/3] PPC PReP: can run without bios image

[Rob Landley <rob@landley.net>]

On 04/04/2013 04:57:32 AM, Artyom Tarasenko wrote:
> On Thu, Apr 4, 2013 at 11:50 AM, Alexander Graf <agraf@suse.de> wrote:
> >
> > On 04.04.2013, at 11:46, Artyom Tarasenko wrote:
> >
> >> On Thu, Apr 4, 2013 at 10:37 AM, Fabien Chouteau  
> <chouteau@adacore.com> wrote:
> >>>
> >>> On 04/03/2013 06:59 PM, Alexander Graf wrote:
> >>>>
> >>>> On 03.04.2013, at 18:40, Fabien Chouteau wrote:
> >>>>
> >>>>> If we use an ELF kernel there's no need for bios. '-bios -'  
> means no
> >>>>> bios.
> >>>>
> >>>> This sounds like you're actually looking for a way to load an  
> ELF blob
> >>>> as bios using -bios, not a kernel, no?
> >>>>
> >>>
> >>> No, we load the kernel with -kernel, that's what the first patch  
> does.
> >>> But the board is implemented in such way that you can't start  
> without a
> >>> bios. If the -bios switch is not present, then the board uses the
> >>> default bios. This patch allows to start without a bios:
> >>>
> >>> -kernel <PROGRAM> -bios -
> >>
> >> Regardless of the firmware vs. kernel discussion, I think the  
> syntax
> >> may be improved. Under *nix '-' is commonly used for stdin. Would  
> it
> >> be possible to specify /dev/null (under *NIX) or NUL (in the
> >> MS-World)? I think it would make the syntax more explicit.
> >
> > I'd be inclined to say that running -kernel without -bios is simply  
> bogus and shouldn't ever happen.
> 
> QEMU does it at least in one other architectures though:  
> leon3_generic.

sh4 runs without bios, arm versatile runs without bios, mips runs  
without bios...

http://landley.net/aboriginal/bin/system-image-armv5l.tar.bz2 (or  
system-image-sh4.tar.bz2 or system-image-mips.tar.bz2) and  
./run-emulator.sh in that. Boots to a shell prompt, no bios.

Rob