Commit Graph

5 Commits

Author SHA1 Message Date
David Gibson
a3467baa88 Delay creation of pseries device tree until reset
At present, the 'pseries' machine creates a flattened device tree in the
machine->init function to pass to either the guest kernel or to firmware.

However, the machine->init function runs before processing of -device
command line options, which means that the device tree so created will
be (incorrectly) missing devices specified that way.

Supplying a correct device tree is, in any case, part of the required
platform entry conditions.  Therefore, this patch moves the creation and
loading of the device tree from machine->init to a reset callback.  The
setup of entry point address and initial register state moves with it,
which leads to a slight cleanup.

This is not, alas, quite enough to make a fully working reset for pseries.
For that we would need to reload the firmware images, which on this
machine are loaded into RAM.  It's a step in the right direction, though.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-04-08 11:32:21 +02:00
David Gibson
b5cec4c5f2 Implement the PAPR (pSeries) virtualized interrupt controller (xics)
PAPR defines an interrupt control architecture which is logically divided
into ICS (Interrupt Control Presentation, each unit is responsible for
presenting interrupts to a particular "interrupt server", i.e. CPU) and
ICS (Interrupt Control Source, each unit responsible for one or more
hardware interrupts as numbered globally across the system).  All PAPR
virtual IO devices expect to deliver interrupts via this mechanism.  In
Linux, this interrupt controller system is handled by the "xics" driver.

On pSeries systems, access to the interrupt controller is virtualized via
hypercalls and RTAS methods.  However, the virtualized interface is very
similar to the underlying interrupt controller hardware, and similar PICs
exist un-virtualized in some other systems.

This patch implements both the ICP and ICS sides of the PAPR interrupt
controller.  For now, only the hypercall virtualized interface is provided,
however it would be relatively straightforward to graft an emulated
register interface onto the underlying interrupt logic if we want to add
a machine with a hardware ICS/ICP system in the future.

There are some limitations in this implementation: it is assumed for now
that only one instance of the ICS exists, although a full xics system can
have several, each responsible for a different group of hardware irqs.
ICP/ICS can handle both level-sensitve (LSI) and message signalled (MSI)
interrupt inputs.  For now, this implementation supports only MSI
interrupts, since that is used by PAPR virtual IO devices.

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>
2011-04-01 18:34:56 +02:00
David Gibson
39ac845510 Implement hcall based RTAS for pSeries machines
On pSeries machines, operating systems can instantiate "RTAS" (Run-Time
Abstraction Services), a runtime component of the firmware which implements
a number of low-level, infrequently used operations.  On logical partitions
under a hypervisor, many of the RTAS functions require hypervisor
privilege.  For simplicity, therefore, hypervisor systems typically
implement the in-partition RTAS as just a tiny wrapper around a hypercall
which actually implements the various RTAS functions.

This patch implements such a hypercall based RTAS for our emulated pSeries
machine.  A tiny in-partition "firmware" calls a new hypercall, which
looks up available RTAS services in a table.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-04-01 18:34:56 +02:00
David Gibson
4040ab7237 Implement the bus structure for PAPR virtual IO
This extends the "pseries" (PAPR) machine to include a virtual IO bus
supporting the PAPR defined hypercall based virtual IO mechanisms.

So far only one VIO device is provided, the vty / vterm, providing
a full console (polled only, for now).

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-04-01 18:34:55 +02:00
David Gibson
9fdf0c2995 Start implementing pSeries logical partition machine
This patch adds a "pseries" machine to qemu.  This aims to emulate a
logical partition on an IBM pSeries machine, compliant to the
"PowerPC Architecture Platform Requirements" (PAPR) document.

This initial version is quite limited, it implements a basic machine
and PAPR hypercall emulation.  So far only one hypercall is present -
H_PUT_TERM_CHAR - so that a (write-only) console is available.

Multiple CPUs are permitted, with SMP entry handled kexec() style.

The machine so far more resembles an old POWER4 style "full system
partition" rather than a modern LPAR, in that the guest manages the
page tables directly, rather than via hypercalls.

The machine requires qemu to be configured with --enable-fdt.  The
machine can (so far) only be booted with -kernel - i.e. no partition
firmware is provided.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-04-01 18:34:55 +02:00