[Qemu-devel] [PATCH] Citrix PV Bus device

[Paul Durrant]

This patch introduces a new PCI device which will act as the binding point
for Citrix branded PV drivers for Xen.
The intention is that Citrix Windows PV drivers will be available on Windows
Update and thus using the existing Xen platform PCI device as an anchor
point is not desirable as that device has been ubiquitous in HVM guests for
a long time and thus existing HVM guests running Windows would start
automatically downloading drivers from Windows Update when this may not be
desired by either the host or guest admin. This device therefore acts as
an opt-in for those wishing to deploy Citrix PV drivers.

Signed-off-by: Paul Durrant <address@hidden>
---
 hw/i386/Makefile.objs    |    1 +
 hw/i386/citrix_pv_bus.c  |  122 ++++++++++++++++++++++++++++++++++++++++++++++
 include/hw/pci/pci_ids.h |    3 ++
 3 files changed, 126 insertions(+)
 create mode 100644 hw/i386/citrix_pv_bus.c

diff --git a/hw/i386/Makefile.objs b/hw/i386/Makefile.objs
index 205d22e..8e28831 100644
--- a/hw/i386/Makefile.objs
+++ b/hw/i386/Makefile.objs
@@ -4,3 +4,4 @@ obj-y += pc.o pc_piix.o pc_q35.o
 obj-$(CONFIG_XEN) += xen_domainbuild.o xen_machine_pv.o
 
 obj-y += kvmvapic.o
+obj-y += citrix_pv_bus.o
diff --git a/hw/i386/citrix_pv_bus.c b/hw/i386/citrix_pv_bus.c
new file mode 100644
index 0000000..e1e0508
--- /dev/null
+++ b/hw/i386/citrix_pv_bus.c
@@ -0,0 +1,122 @@
+/* Copyright (c) Citrix Systems Inc.
+ * All rights reserved.
+ * 
+ * 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.
+ * 
+ * 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 HOLDER 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.
+ */
+
+#include "hw/hw.h"
+#include "hw/pci/pci.h"
+
+typedef struct _CitrixPVBusDevice {
+    PCIDevice       dev;
+    uint8_t         revision;
+    uint32_t        pages;
+    MemoryRegion    mmio;
+} CitrixPVBusDevice;
+
+static uint64_t citrix_pv_bus_mmio_read(void *opaque, hwaddr addr,
+                                        unsigned size)
+{
+    fprintf(stderr, "WARNING: read from address 0x" TARGET_FMT_plx
+            " in Citrix PV Bus MMIO BAR\n", addr);
+
+    return ~(uint64_t)0;
+}
+
+static void citrix_pv_bus_mmio_write(void *opaque, hwaddr addr,
+                                     uint64_t val, unsigned size)
+{
+    fprintf(stderr, "WARNING: write to address 0x" TARGET_FMT_plx
+            " in Citrix PV Bus MMIO BAR\n", addr);
+}
+
+static const MemoryRegionOps citrix_pv_bus_mmio_ops = {
+    .read = &citrix_pv_bus_mmio_read,
+    .write = &citrix_pv_bus_mmio_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static int citrix_pv_bus_init(PCIDevice *pci_dev)
+{
+    CitrixPVBusDevice *d = DO_UPCAST(CitrixPVBusDevice, dev, pci_dev);
+    uint8_t *pci_conf;
+    uint64_t size;
+
+    pci_conf = pci_dev->config;
+
+    pci_set_word(pci_conf + PCI_COMMAND, PCI_COMMAND_MEMORY);
+    pci_set_byte(pci_conf + PCI_REVISION_ID, d->revision);
+
+    pci_config_set_prog_interface(pci_conf, 0);
+
+    pci_conf[PCI_INTERRUPT_PIN] = 1;
+
+    size = d->pages * TARGET_PAGE_SIZE;
+    memory_region_init_io(&d->mmio, &citrix_pv_bus_mmio_ops, d,
+                          "citrix-bus-mmio", size);
+
+    pci_register_bar(pci_dev, 1, PCI_BASE_ADDRESS_MEM_PREFETCH,
+                     &d->mmio);
+
+    return 0;
+}
+
+static Property citrix_pv_bus_props[] = {
+    DEFINE_PROP_UINT8("revision", CitrixPVBusDevice, revision, 0x01),
+    DEFINE_PROP_UINT32("pages", CitrixPVBusDevice, pages, 128),
+    DEFINE_PROP_END_OF_LIST()
+};
+
+static void citrix_pv_bus_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
+
+    k->init = citrix_pv_bus_init;
+    k->vendor_id = PCI_VENDOR_ID_CITRIX;
+    k->device_id = PCI_DEVICE_ID_CITRIX_PV_BUS;
+    k->class_id = PCI_CLASS_SYSTEM_OTHER;
+    k->subsystem_vendor_id = PCI_VENDOR_ID_CITRIX;
+    k->subsystem_id = PCI_DEVICE_ID_CITRIX_PV_BUS;
+    dc->desc = "Citrix PV Bus";
+    dc->props = citrix_pv_bus_props;
+}
+
+static const TypeInfo citrix_pv_bus_type_info = {
+    .name          = "citrix-pv-bus",
+    .parent        = TYPE_PCI_DEVICE,
+    .instance_size = sizeof(CitrixPVBusDevice),
+    .class_init    = citrix_pv_bus_class_init,
+};
+
+static void citrix_pv_bus_register_types(void)
+{
+    type_register_static(&citrix_pv_bus_type_info);
+}
+
+type_init(citrix_pv_bus_register_types)
diff --git a/include/hw/pci/pci_ids.h b/include/hw/pci/pci_ids.h
index d8dc2f1..ed6a059 100644
--- a/include/hw/pci/pci_ids.h
+++ b/include/hw/pci/pci_ids.h
@@ -151,4 +151,7 @@
 #define PCI_VENDOR_ID_TEWS               0x1498
 #define PCI_DEVICE_ID_TEWS_TPCI200       0x30C8
 
+#define PCI_VENDOR_ID_CITRIX             0x5853
+#define PCI_DEVICE_ID_CITRIX_PV_BUS      0x0002
+
 #endif
-- 
1.7.10.4