dev, pci: Implement basic VirtIO support

This patch adds support for VirtIO over the PCI bus. It does so by
providing the following new SimObjects:

 * VirtIODeviceBase - Abstract base class for VirtIO devices.
 * PciVirtIO - VirtIO PCI transport interface.

A VirtIO device is hooked up to the guest system by adding a PciVirtIO
device to the PCI bus and connecting it to a VirtIO device using the
vio parameter.

New VirtIO devices should inherit from VirtIODevice base and
implementing one or more VirtQueues. The VirtQueues are usually
device-specific and all derive from the VirtQueue class. Queues must
be registered with the base class from the constructor since the
device assumes that the number of queues stay constant.

1 files changed, 71 insertions, 0 deletions

diff --git a/src/dev/virtio/VirtIO.py b/src/dev/virtio/VirtIO.py
new file mode 100644
index 000000000..13479a383
--- /dev/null
+++ b/src/dev/virtio/VirtIO.py
@@ -0,0 +1,71 @@
+# -*- mode:python -*-
+
+# Copyright (c) 2014 ARM Limited
+# All rights reserved.
+#
+# The license below extends only to copyright in the software and shall
+# not be construed as granting a license to any other intellectual
+# property including but not limited to intellectual property relating
+# to a hardware implementation of the functionality of the software
+# licensed hereunder.  You may use the software subject to the license
+# terms below provided that you ensure that this notice is replicated
+# unmodified and in its entirety in all distributions of the software,
+# modified or unmodified, in source code or in binary form.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# Authors: Andreas Sandberg
+
+from m5.SimObject import SimObject
+from m5.params import *
+from m5.proxy import *
+from Device import PioDevice
+from Pci import PciDevice
+
+
+class VirtIODeviceBase(SimObject):
+    type = 'VirtIODeviceBase'
+    cxx_header = 'dev/virtio/base.hh'
+    abstract = True
+
+    subsystem = Param.UInt8(0x00, "VirtIO subsystem ID")
+
+    system = Param.System(Parent.any, "system object")
+
+class PciVirtIO(PciDevice):
+    type = 'PciVirtIO'
+    cxx_header = 'dev/virtio/pci.hh'
+
+    vio = Param.VirtIODeviceBase("VirtIO device")
+
+    VendorID = 0x1AF4
+    SubsystemVendorID = VendorID;
+    DeviceID = 0x1000
+
+    ClassCode = 0xff # Misc device
+
+    BAR0 = 0x00000000 # Anywhere in 32-bit space
+    BAR0Size = '0B' # Overridden by the device model
+
+    InterruptPin = 0x01 # Use #INTA