Re: [Qemu-devel] [Qemu-ppc] Qemu boot device precedence over nvram boot-device setting

[Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>]

On Thu, 27 Sep 2012 12:13:05 +0200, Gleb Natapov <gleb@redhat.com> wrote:
> On Thu, Sep 27, 2012 at 03:35:53PM +0530, Nikunj A Dadhania wrote:
> > 
> > If the user does not set bootindex, qemu would decide the bootindex?  
> > 
> No. Firmware decides. QEMU just tells to firmware that it does not have
> bootindex.

Ok. That should work in that case, we need to make sure that bootindex
is being send via device-tree. I do not see such code in place
currently.

> 
> > If it does, there will be a default bootindex. Then the problem still
> > remains, qemu decided the boot-order, in which case we would want to
> > pick the nvram based setting. This is again difficult to distinguish.
> > 
> > > There is nothing "blurry" about OF device
> > > path. The problem is that it works reasonably well with legacy BIOS
> > > since it is enough to specify device to boot from, but with EFI (OF is
> > > the same I guess) it is not enough to point to a device to boot from,
> > > but you also need to specify a file you want to boot and this is where
> > > bootindex approach fails.
> > 
> > By file I suppose you mean OF device-path. 
> > 
> No. By file I mean a file on dedicated EFI FAT partition that EFI loads
> during boot.  I do not know if OF has something similar.
> 
No, it just needs the device-path. Rest it figures out.

Regards
Nikunj