pci: recognize RH PCI legacy bridge resource reservation capability

Enable the firmware recognizing RedHat legacy PCI bridge device ID,
so QEMU can reserve additional PCI bridge resource capability.
Change the debug level lower to 3 when it is non-QEMU bridge.

Signed-off-by: Jing Liu <jing2.liu@linux.intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Marcel Apfelbaum<marcel.apfelbaum@gmail.com>
Message-id: 1535100781-3910-4-git-send-email-jing2.liu@linux.intel.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
diff --git a/src/fw/pciinit.c b/src/fw/pciinit.c
index 62a32f1..c0634bc 100644
--- a/src/fw/pciinit.c
+++ b/src/fw/pciinit.c
@@ -525,30 +525,38 @@
 
 static u8 pci_find_resource_reserve_capability(u16 bdf)
 {
-    if (pci_config_readw(bdf, PCI_VENDOR_ID) == PCI_VENDOR_ID_REDHAT &&
-        pci_config_readw(bdf, PCI_DEVICE_ID) ==
-                PCI_DEVICE_ID_REDHAT_ROOT_PORT) {
-        u8 cap = 0;
-        do {
-            cap = pci_find_capability(bdf, PCI_CAP_ID_VNDR, cap);
-        } while (cap &&
-                 pci_config_readb(bdf, cap + PCI_CAP_REDHAT_TYPE_OFFSET) !=
-                        REDHAT_CAP_RESOURCE_RESERVE);
-        if (cap) {
-            u8 cap_len = pci_config_readb(bdf, cap + PCI_CAP_FLAGS);
-            if (cap_len < RES_RESERVE_CAP_SIZE) {
-                dprintf(1, "PCI: QEMU resource reserve cap length %d is invalid\n",
-                        cap_len);
-                return 0;
-            }
-        } else {
-            dprintf(1, "PCI: QEMU resource reserve cap not found\n");
-        }
-        return cap;
-    } else {
-        dprintf(1, "PCI: QEMU resource reserve cap VID or DID doesn't match.\n");
+    u16 device_id;
+
+    if (pci_config_readw(bdf, PCI_VENDOR_ID) != PCI_VENDOR_ID_REDHAT) {
+        dprintf(3, "PCI: This is non-QEMU bridge.\n");
         return 0;
     }
+
+    device_id = pci_config_readw(bdf, PCI_DEVICE_ID);
+
+    if (device_id != PCI_DEVICE_ID_REDHAT_ROOT_PORT &&
+        device_id != PCI_DEVICE_ID_REDHAT_BRIDGE) {
+        dprintf(1, "PCI: QEMU resource reserve cap device ID doesn't match.\n");
+        return 0;
+    }
+    u8 cap = 0;
+
+    do {
+        cap = pci_find_capability(bdf, PCI_CAP_ID_VNDR, cap);
+    } while (cap &&
+             pci_config_readb(bdf, cap + PCI_CAP_REDHAT_TYPE_OFFSET) !=
+                              REDHAT_CAP_RESOURCE_RESERVE);
+    if (cap) {
+        u8 cap_len = pci_config_readb(bdf, cap + PCI_CAP_FLAGS);
+        if (cap_len < RES_RESERVE_CAP_SIZE) {
+            dprintf(1, "PCI: QEMU resource reserve cap length %d is invalid\n",
+                    cap_len);
+            return 0;
+        }
+    } else {
+        dprintf(1, "PCI: QEMU resource reserve cap not found\n");
+    }
+    return cap;
 }
 
 /****************************************************************
diff --git a/src/hw/pci_ids.h b/src/hw/pci_ids.h
index 38fa2ca..1096461 100644
--- a/src/hw/pci_ids.h
+++ b/src/hw/pci_ids.h
@@ -2265,6 +2265,7 @@
 
 #define PCI_VENDOR_ID_REDHAT		0x1b36
 #define PCI_DEVICE_ID_REDHAT_ROOT_PORT	0x000C
+#define PCI_DEVICE_ID_REDHAT_BRIDGE	0x0001
 
 #define PCI_VENDOR_ID_TEKRAM		0x1de1
 #define PCI_DEVICE_ID_TEKRAM_DC290	0xdc29