Re: [Qemu-devel] [PATCH 27/27] Add SLOF-based partition firmware for pSeries machine, allowing more boot options

[David Gibson <david@gibson.dropbear.id.au>]

On Fri, Mar 25, 2011 at 01:29:17PM -0500, Anthony Liguori wrote:
> On 03/24/2011 10:21 PM, David Gibson wrote:
> >Currently, the emulated pSeries machine requires the use of the
> >-kernel parameter in order to explicitly load a guest kernel.  This
> >means booting from the virtual disk, cdrom or network is not possible.
> >
> >This patch addresses this limitation by inserting a within-partition
> >firmware image (derived from the "SLOF" free Open Firmware project).
> >If -kernel is not specified, qemu will now load the SLOF image, which
> >has access to the qemu boot device list through the device tree, and
> >can boot from any of the usual virtual devices.
> >
> >In order to support the new firmware, an extension to the emulated
> >machine/hypervisor is necessary.  Unlike Linux, which expects
> >multi-CPU entry to be handled kexec() style, the SLOF firmware expects
> >only one CPU to be active at entry, and to use a hypervisor RTAS
> >method to enable the other CPUs one by one.
> >
> >This patch also implements this 'start-cpu' method, so that SLOF can
> >start the secondary CPUs and marshal them into the kexec() holding
> >pattern ready for entry into the guest OS.  Linux should, and in the
> >future might directly use the start-cpu method to enable initially
> >disabled CPUs, but for now it does require kexec() entry.
> >
> >Signed-off-by: Benjamin Herrenschmidt<benh@kernel.crashing.org>
> >Signed-off-by: Paul Mackerras<paulus@samba.org>
> >Signed-off-by: David Gibson<dwg@au1.ibm.com>
> 
> We should pull in SLOF via a git submodule.  That ensures we ship
> the source code along with the binary.

Um, ok.  Do I need to do anything about this?

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson