Hello Nikos Nikoleris,
I'd like you to do a code review. Please visit
https://gem5-review.googlesource.com/2326
to review the following change.
Change subject: dev: Add a MMIO transport interface for VirtIO
......................................................................
dev: Add a MMIO transport interface for VirtIO
Add an implementation of the VirtIO MMIO transport interface. Due to
the way gem5 handles interrupts, each architecture needs its own
specialization of this class to implement interrupts.
An architecture-specific implementation needs to provide an
implementation of these methods:
void raiseInterrupt();
void clearInterrupt();
The MMIO interface currently only supports a subset of version 0.9.5
of the VirtIO specification. It has the following known limitations:
* The queue size hint (the QUEUE_NUM register) is ignored.
* Queue alignment is assumed to be hard-coded to
VirtQueue::ALIGN_SIZE (4096 bytes).
* Only 4096 byte pages are currently supported.
Change-Id: Ifd318f5e5bddab0b6a42d8c8af9ff2fbb477f98b
Signed-off-by: Andreas Sandberg <[email protected]>
Reviewed-by: Nikos Nikoleris <[email protected]>
Reviewed-by: Rekai Gonzalez Alberquilla <[email protected]>
---
M src/dev/virtio/SConscript
M src/dev/virtio/VirtIO.py
A src/dev/virtio/mmio.cc
A src/dev/virtio/mmio.hh
4 files changed, 402 insertions(+), 1 deletion(-)
diff --git a/src/dev/virtio/SConscript b/src/dev/virtio/SConscript
index 3b346e9..b18ac4e 100644
--- a/src/dev/virtio/SConscript
+++ b/src/dev/virtio/SConscript
@@ -49,6 +49,7 @@
Source('base.cc')
Source('pci.cc')
+Source('mmio.cc')
Source('console.cc')
Source('block.cc')
Source('fs9p.cc')
diff --git a/src/dev/virtio/VirtIO.py b/src/dev/virtio/VirtIO.py
index bf050fd..1d66d55 100644
--- a/src/dev/virtio/VirtIO.py
+++ b/src/dev/virtio/VirtIO.py
@@ -40,7 +40,7 @@
from m5.SimObject import SimObject
from m5.params import *
from m5.proxy import *
-from Device import PioDevice
+from Device import BasicPioDevice
from PciDevice import PciDevice
@@ -73,3 +73,12 @@
BAR0Size = '0B' # Overridden by the device model
InterruptPin = 0x01 # Use #INTA
+
+class MmioVirtIO(BasicPioDevice):
+ type = 'MmioVirtIO'
+ cxx_header = 'dev/virtio/mmio.hh'
+ abstract = True
+
+ pio_size = Param.Addr(4096, "IO range")
+
+ vio = Param.VirtIODeviceBase(VirtIODummyDevice(), "VirtIO device")
diff --git a/src/dev/virtio/mmio.cc b/src/dev/virtio/mmio.cc
new file mode 100644
index 0000000..995b64b
--- /dev/null
+++ b/src/dev/virtio/mmio.cc
@@ -0,0 +1,274 @@
+/*
+ * Copyright (c) 2016 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
+ */
+
+#include "dev/virtio/mmio.hh"
+
+#include "debug/VIOIface.hh"
+#include "mem/packet_access.hh"
+#include "params/MmioVirtIO.hh"
+
+MmioVirtIO::MmioVirtIO(const MmioVirtIOParams *params)
+ : BasicPioDevice(params, params->pio_size),
+ hostFeaturesSelect(0), guestFeaturesSelect(0), pageSize(0),
+ interruptStatus(0),
+ callbackKick(this), vio(*params->vio)
+{
+ vio.registerKickCallback(&callbackKick);
+}
+
+MmioVirtIO::~MmioVirtIO()
+{
+}
+
+Tick
+MmioVirtIO::read(PacketPtr pkt)
+{
+ const Addr offset = pkt->getAddr() - pioAddr;
+ const unsigned size(pkt->getSize());
+
+ DPRINTF(VIOIface, "Reading %u bytes @ 0x%x:\n", size, offset);
+
+ // Forward device configuration writes to the device VirtIO model
+ if (offset >= OFF_CONFIG) {
+ vio.readConfig(pkt, offset - OFF_CONFIG);
+ return 0;
+ }
+
+ panic_if(size != 4, "Unexpected read size: %u\n", size);
+
+ const uint32_t value = read(offset);
+ DPRINTF(VIOIface, " value: 0x%x\n", value);
+ pkt->makeResponse();
+ pkt->set<uint32_t>(value);
+
+ return 0;
+}
+
+uint32_t
+MmioVirtIO::read(Addr offset)
+{
+ switch(offset) {
+ case OFF_MAGIC:
+ return MAGIC;
+
+ case OFF_VERSION:
+ return VERSION;
+
+ case OFF_DEVICE_ID:
+ return vio.deviceId;
+
+ case OFF_VENDOR_ID:
+ return VENDOR_ID;
+
+ case OFF_HOST_FEATURES:
+ // We only implement 32 bits of this register
+ if (hostFeaturesSelect == 0)
+ return vio.deviceFeatures;
+ else
+ return 0;
+
+ case OFF_HOST_FEATURES_SELECT:
+ return hostFeaturesSelect;
+
+ case OFF_GUEST_FEATURES:
+ // We only implement 32 bits of this register
+ if (guestFeaturesSelect == 0)
+ return vio.getGuestFeatures();
+ else
+ return 0;
+
+ case OFF_GUEST_FEATURES_SELECT:
+ return hostFeaturesSelect;
+
+ case OFF_GUEST_PAGE_SIZE:
+ return pageSize;
+
+ case OFF_QUEUE_SELECT:
+ return vio.getQueueSelect();
+
+ case OFF_QUEUE_NUM_MAX:
+ return vio.getQueueSize();
+
+ case OFF_QUEUE_NUM:
+ // TODO: We don't support queue resizing, so ignore this for now.
+ return vio.getQueueSize();
+
+ case OFF_QUEUE_ALIGN:
+ // TODO: Implement this once we support other alignment sizes
+ return VirtQueue::ALIGN_SIZE;
+
+ case OFF_QUEUE_PFN:
+ return vio.getQueueAddress();
+
+ case OFF_INTERRUPT_STATUS:
+ return interruptStatus;
+
+ case OFF_STATUS:
+ return vio.getDeviceStatus();
+
+ // Write-only registers
+ case OFF_QUEUE_NOTIFY:
+ case OFF_INTERRUPT_ACK:
+ warn("Guest is trying to read to write-only register 0x%\n",
+ offset);
+ return 0;
+
+ default:
+ panic("Unhandled read offset (0x%x)\n", offset);
+ }
+}
+
+Tick
+MmioVirtIO::write(PacketPtr pkt)
+{
+ const Addr offset = pkt->getAddr() - pioAddr;
+ const unsigned size(pkt->getSize());
+
+ DPRINTF(VIOIface, "Writing %u bytes @ 0x%x:\n", size, offset);
+
+ // Forward device configuration writes to the device VirtIO model
+ if (offset >= OFF_CONFIG) {
+ vio.writeConfig(pkt, offset - OFF_CONFIG);
+ return 0;
+ }
+
+ panic_if(size != 4, "Unexpected write size @ 0x%x: %u\n", offset,
size);
+ DPRINTF(VIOIface, " value: 0x%x\n", pkt->get<uint32_t>());
+ pkt->makeResponse();
+ write(offset, pkt->get<uint32_t>());
+ return 0;
+}
+
+void
+MmioVirtIO::write(Addr offset, uint32_t value)
+{
+ switch(offset) {
+ case OFF_HOST_FEATURES_SELECT:
+ hostFeaturesSelect = value;
+ return;
+
+ case OFF_GUEST_FEATURES:
+ if (guestFeaturesSelect == 0) {
+ vio.setGuestFeatures(value);
+ } else if (value != 0) {
+ warn("Setting unimplemented guest features register %u: %u\n",
+ guestFeaturesSelect, value);
+ }
+ return;
+
+ case OFF_GUEST_FEATURES_SELECT:
+ guestFeaturesSelect = value;
+ return;
+
+ case OFF_GUEST_PAGE_SIZE:
+ // TODO: We only support 4096 byte pages at the moment
+ panic_if(value != VirtQueue::ALIGN_SIZE,
+ "Unhandled VirtIO page size: %u", value);
+ pageSize = value;
+ return;
+
+ case OFF_QUEUE_SELECT:
+ vio.setQueueSelect(value);
+ return;
+
+ case OFF_QUEUE_NUM:
+ // TODO: We don't support queue resizing, so ignore this for now.
+ warn_once("Ignoring queue resize hint. Requested size: %u\n",
value);
+ return;
+
+ case OFF_QUEUE_ALIGN:
+ // TODO: We currently only support the hard-coded 4k alignment used
+ // in legacy VirtIO.
+ panic_if(value != VirtQueue::ALIGN_SIZE,
+ "Unhandled VirtIO alignment size: %u", value);
+ return;
+
+ case OFF_QUEUE_PFN:
+ vio.setQueueAddress(value);
+ return;
+
+ case OFF_QUEUE_NOTIFY:
+ vio.onNotify(value);
+ return;
+
+ case OFF_INTERRUPT_ACK:
+ setInterrupts(interruptStatus & (~value));
+ return;
+
+ case OFF_STATUS:
+ panic_if(value > 0xff, "Unexpected status: 0x%x\n", value);
+ vio.setDeviceStatus(value);
+ return;
+
+ /* Read-only registers */
+ case OFF_MAGIC:
+ case OFF_VERSION:
+ case OFF_DEVICE_ID:
+ case OFF_VENDOR_ID:
+ case OFF_HOST_FEATURES:
+ case OFF_QUEUE_NUM_MAX:
+ case OFF_INTERRUPT_STATUS:
+ warn("Guest is trying to write to read-only register 0x%\n",
+ offset);
+ return;
+
+ default:
+ panic("Unhandled read offset (0x%x)\n", offset);
+ }
+}
+
+void
+MmioVirtIO::kick()
+{
+ DPRINTF(VIOIface, "kick(): Sending interrupt...\n");
+ setInterrupts(interruptStatus | INT_USED_RING);
+}
+
+void
+MmioVirtIO::setInterrupts(uint32_t value)
+{
+ const uint32_t old_ints = interruptStatus;
+ interruptStatus = value;
+
+ if (!old_ints && interruptStatus) {
+ raiseInterrupt();
+ } else if (old_ints && !interruptStatus) {
+ clearInterrupt();
+ }
+}
diff --git a/src/dev/virtio/mmio.hh b/src/dev/virtio/mmio.hh
new file mode 100644
index 0000000..2c65f2d
--- /dev/null
+++ b/src/dev/virtio/mmio.hh
@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2016 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
+ */
+
+#ifndef __DEV_VIRTIO_MMIO_HH__
+#define __DEV_VIRTIO_MMIO_HH__
+
+#include "dev/io_device.hh"
+#include "dev/virtio/base.hh"
+
+struct MmioVirtIOParams;
+
+class MmioVirtIO : public BasicPioDevice
+{
+ public:
+ MmioVirtIO(const MmioVirtIOParams *params);
+ virtual ~MmioVirtIO();
+
+ protected: // BasicPioDevice
+ Tick read(PacketPtr pkt);
+ Tick write(PacketPtr pkt);
+
+ protected:
+ virtual void raiseInterrupt() = 0;
+ virtual void clearInterrupt() = 0;
+
+ protected:
+ /** @{ */
+ /** Offsets into VirtIO MMIO space. */
+
+ enum : Addr {
+ OFF_MAGIC = 0x00,
+ OFF_VERSION = 0x04,
+ OFF_DEVICE_ID = 0x08,
+ OFF_VENDOR_ID = 0x0C,
+ OFF_HOST_FEATURES = 0x10,
+ OFF_HOST_FEATURES_SELECT = 0x14,
+ OFF_GUEST_FEATURES = 0x20,
+ OFF_GUEST_FEATURES_SELECT = 0x24,
+ OFF_GUEST_PAGE_SIZE = 0x28,
+ OFF_QUEUE_SELECT = 0x30,
+ OFF_QUEUE_NUM_MAX = 0x34,
+ OFF_QUEUE_NUM = 0x38,
+ OFF_QUEUE_ALIGN = 0x3C,
+ OFF_QUEUE_PFN = 0x40,
+ OFF_QUEUE_NOTIFY = 0x50,
+ OFF_INTERRUPT_STATUS = 0x60,
+ OFF_INTERRUPT_ACK = 0x64,
+ OFF_STATUS = 0x70,
+ OFF_CONFIG = 0x100,
+ };
+
+ /** @} */
+
+ enum {
+ INT_USED_RING = 1 << 0,
+ INT_CONFIG = 1 << 1,
+ };
+
+ const uint32_t MAGIC = 0x74726976;
+ const uint32_t VERSION = 1;
+ const uint32_t VENDOR_ID = 0x1AF4;
+
+
+ uint32_t read(Addr offset);
+ void write(Addr offset, uint32_t value);
+
+ void kick();
+ void setInterrupts(uint32_t value);
+
+ uint32_t hostFeaturesSelect;
+ uint32_t guestFeaturesSelect;
+ uint32_t pageSize;
+ uint32_t interruptStatus;
+
+ MakeCallback<MmioVirtIO, &MmioVirtIO::kick> callbackKick;
+
+ protected: // Params
+ VirtIODeviceBase &vio;
+};
+
+#endif // __DEV_VIRTIO_MMIO_HH__
--
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Gerrit-Project: public/gem5
Gerrit-Branch: master
Gerrit-MessageType: newchange
Gerrit-Change-Id: Ifd318f5e5bddab0b6a42d8c8af9ff2fbb477f98b
Gerrit-Change-Number: 2326
Gerrit-PatchSet: 1
Gerrit-Owner: Andreas Sandberg <[email protected]>
Gerrit-Reviewer: Nikos Nikoleris <[email protected]>
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