[Qemu-devel] [v2][PATCH 5/8] xen, gfx passthrough: create intel isa bridge

[Tiejun Chen]

ISA bridge is needed since Intel gfx drive will probe it instead
of Dev31:Fun0 to make graphics device passthrough work easy for VMM, that
only need to expose ISA bridge to let driver know the real hardware underneath.

The original patch is from Allen Kay address@hidden

Signed-off-by: Yang Zhang <address@hidden>
Signed-off-by: Tiejun Chen <address@hidden>
Cc: Allen Kay <address@hidden>
---
v2:

* Nothing is changed.

 hw/xen/xen_pt_graphics.c | 71 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 71 insertions(+)

diff --git a/hw/xen/xen_pt_graphics.c b/hw/xen/xen_pt_graphics.c
index e1f0724..6b86293 100644
--- a/hw/xen/xen_pt_graphics.c
+++ b/hw/xen/xen_pt_graphics.c
@@ -175,3 +175,74 @@ out:
     g_free(bios);
     return rc;
 }
+
+static uint32_t isa_bridge_read_config(PCIDevice *d, uint32_t addr, int len)
+{
+    uint32_t v;
+
+    v = pci_default_read_config(d, addr, len);
+
+    return v;
+}
+
+static void isa_bridge_write_config(PCIDevice *d, uint32_t addr, uint32_t v,
+                                    int len)
+{
+    pci_default_write_config(d, addr, v, len);
+
+    return;
+}
+
+static void isa_bridge_class_init(ObjectClass *klass, void *data)
+{
+    PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
+
+    k->config_read = isa_bridge_read_config;
+    k->config_write = isa_bridge_write_config;
+
+    return;
+};
+
+typedef struct {
+    PCIDevice dev;
+} ISABridgeState;
+
+static TypeInfo isa_bridge_info = {
+    .name          = "inte-pch-isa-bridge",
+    .parent        = TYPE_PCI_DEVICE,
+    .instance_size = sizeof(ISABridgeState),
+    .class_init = isa_bridge_class_init,
+};
+
+static void xen_pt_graphics_register_types(void)
+{
+    type_register_static(&isa_bridge_info);
+}
+
+type_init(xen_pt_graphics_register_types)
+
+static int create_pch_isa_bridge(PCIBus *bus, XenHostPCIDevice *hdev)
+{
+    struct PCIDevice *dev;
+
+    char rid;
+
+    dev = pci_create(bus, PCI_DEVFN(0x1f, 0), "inte-pch-isa-bridge");
+    if (!dev) {
+        XEN_PT_LOG(dev, "fail to create PCH ISA bridge.\n");
+        return -1;
+    }
+
+    qdev_init_nofail(&dev->qdev);
+
+    pci_config_set_vendor_id(dev->config, hdev->vendor_id);
+    pci_config_set_device_id(dev->config, hdev->device_id);
+
+    xen_host_pci_get_block(hdev, PCI_REVISION_ID, (uint8_t *)&rid, 1);
+
+    pci_config_set_revision(dev->config, rid);
+    pci_config_set_class(dev->config, PCI_CLASS_BRIDGE_ISA);
+
+    XEN_PT_LOG(dev, "Intel PCH ISA bridge is created.\n");
+    return 0;
+}
-- 
1.9.1