[Qemu-devel] [v5][PATCH 4/5] xen, gfx passthrough: create host bridge to passthrough

[Tiejun Chen]

Implement that pci host bridge to specific to passthrough. Actually
this just inherit the standard one.

Signed-off-by: Tiejun Chen <address@hidden>
---
v5:

* Nothing is changed.

v4:

* Fix one typo in the patch head description.
* Use (xen_enabled() && xen_has_gfx_passthru) to make sure we only work
  in this scenario.

v3:

* Just fix this patch head description typo.

v2:

* New patch.

 hw/pci-host/piix.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 54 insertions(+), 2 deletions(-)

diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c
index e0e0946..9acf901 100644
--- a/hw/pci-host/piix.c
+++ b/hw/pci-host/piix.c
@@ -34,6 +34,7 @@
 #include "sysemu/sysemu.h"
 #include "hw/i386/ioapic.h"
 #include "qapi/visitor.h"
+#include "hw/xen/xen_pt.h"
 
 /*
  * I440FX chipset data sheet.
@@ -95,6 +96,10 @@ typedef struct PIIX3State {
 #define I440FX_PCI_DEVICE(obj) \
     OBJECT_CHECK(PCII440FXState, (obj), TYPE_I440FX_PCI_DEVICE)
 
+#define TYPE_I440FX_XEN_PCI_DEVICE "i440FX-xen"
+#define I440FX_XEN_PCI_DEVICE(obj) \
+    OBJECT_CHECK(PCII440FXState, (obj), TYPE_I440FX_XEN_PCI_DEVICE)
+
 struct PCII440FXState {
     /*< private >*/
     PCIDevice parent_obj;
@@ -305,6 +310,16 @@ static int i440fx_initfn(PCIDevice *dev)
     return 0;
 }
 
+static int i440fx_xen_initfn(PCIDevice *dev)
+{
+    PCII440FXState *d = I440FX_XEN_PCI_DEVICE(dev);
+
+    dev->config[I440FX_SMRAM] = 0x02;
+
+    cpu_smm_register(&i440fx_set_smm, d);
+    return 0;
+}
+
 PCIBus *i440fx_init(PCII440FXState **pi440fx_state,
                     int *piix3_devfn,
                     ISABus **isa_bus, qemu_irq *pic,
@@ -333,8 +348,15 @@ PCIBus *i440fx_init(PCII440FXState **pi440fx_state,
     object_property_add_child(qdev_get_machine(), "i440fx", OBJECT(dev), NULL);
     qdev_init_nofail(dev);
 
-    d = pci_create_simple(b, 0, TYPE_I440FX_PCI_DEVICE);
-    *pi440fx_state = I440FX_PCI_DEVICE(d);
+    if (xen_enabled() && xen_has_gfx_passthru) {
+        d = pci_create_simple(b, 0, TYPE_I440FX_XEN_PCI_DEVICE);
+        *pi440fx_state = I440FX_XEN_PCI_DEVICE(d);
+        pci_create_pch(b);
+    } else {
+        d = pci_create_simple(b, 0, TYPE_I440FX_PCI_DEVICE);
+        *pi440fx_state = I440FX_PCI_DEVICE(d);
+    }
+
     f = *pi440fx_state;
     f->system_memory = address_space_mem;
     f->pci_address_space = pci_address_space;
@@ -704,6 +726,35 @@ static const TypeInfo i440fx_info = {
     .class_init    = i440fx_class_init,
 };
 
+static void i440fx_xen_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
+
+    k->init = i440fx_xen_initfn;
+    k->config_write = igd_pci_write;
+    k->config_read = igd_pci_read;
+    k->vendor_id = PCI_VENDOR_ID_INTEL;
+    k->device_id = PCI_DEVICE_ID_INTEL_82441;
+    k->revision = 0x02;
+    k->class_id = PCI_CLASS_BRIDGE_ISA;
+    dc->desc = "XEN Host bridge";
+    dc->vmsd = &vmstate_i440fx;
+    /*
+     * PCI-facing part of the host bridge, not usable without the
+     * host-facing part, which can't be device_add'ed, yet.
+     */
+    dc->cannot_instantiate_with_device_add_yet = true;
+    dc->hotpluggable   = false;
+}
+
+static const TypeInfo i440fx_xen_info = {
+    .name          = TYPE_I440FX_XEN_PCI_DEVICE,
+    .parent        = TYPE_PCI_DEVICE,
+    .instance_size = sizeof(PCII440FXState),
+    .class_init    = i440fx_xen_class_init,
+};
+
 static const char *i440fx_pcihost_root_bus_path(PCIHostState *host_bridge,
                                                 PCIBus *rootbus)
 {
@@ -745,6 +796,7 @@ static const TypeInfo i440fx_pcihost_info = {
 static void i440fx_register_types(void)
 {
     type_register_static(&i440fx_info);
+    type_register_static(&i440fx_xen_info);
     type_register_static(&piix3_info);
     type_register_static(&piix3_xen_info);
     type_register_static(&i440fx_pcihost_info);
-- 
1.9.1