Currently on the pseries machine the SLOF firmware is used normally,
but we bypass it when -kernel is specified. Having these two
different boot paths can cause some confusion.
In particular at present we need to "probe" the (emulated) PCI bus and
produce device tree nodes for the PCI devices in qemu, for the -kernel
case. In the SLOF case, it takes the device tree from qemu adds some
stuff to it then passes it on to the kernel.
It's been decided that a better approach is to always boot through
SLOF, even when using -kernel. WIth this approach we can leave PCI
probing and device node creation to SLOF in all cases which removes a
bunch of code in qemu, and avoids iterating the PCI devices from the
machine specific init code which we're not supposed to do.
This patch changes qemu to always boot through SLOF, and not to create
PCI nodes. Simultaneously it updates the included version of SLOF
(submodule and binary image) to one which supports (and requires) the
new approach.
The new SLOF version also includes a number of unrelated enhancements:
support for booting from virtio-pci devices and e1000, greatly
improved FCode support and many bugfixes. It also makes SLOF ready to
be used even when specifying a kernel on the qemu command line.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
This patch is a general update to the SLOF firmware image used on the
pseries machine. This doesn't contain updates for specific features but
contains a number of bugfixes and enhancements in the main SLOF tree from
Thomas Huth.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
This patch updates the SLOF submodule and precompiled image. The new
SLOF versions contains two changes of note:
* The previous SLOF has a bug in SCSI condition handling that was
exposed by recent updates to qemu's SCSI emulation. This update
fixes the bug.
* The previous SLOF has a bug in its addressing of SCSI devices,
which can be exposed under certain conditions. The new SLOF also
fixes this.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
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>
Signed-off-by: Alexander Graf <agraf@suse.de>
