From 35540106538b24ca1765e752fe9d6efc968a88fa Mon Sep 17 00:00:00 2001
From: Egbert Eich <eich@linux-p1mv.site>
Date: Wed, 7 Oct 2009 16:31:44 +0200
Subject: [PATCH] Check harder for primary PCI device.

Primary PCI devices are identified by checking for an 'PCIINFOCLASSES'
device which is VGA and has access to the memory bars enabled.
If there should be more than one device for which this is true
redo the check and also check if IO resoures are also enabled,
if this still doesn't turn up a unique result also check for
the presence of a BIOS rom.
================================================================================
Index: xorg-server-1.12.1/hw/xfree86/common/xf86pciBus.c
===================================================================
--- xorg-server-1.12.1.orig/hw/xfree86/common/xf86pciBus.c
+++ xorg-server-1.12.1/hw/xfree86/common/xf86pciBus.c
@@ -134,9 +134,50 @@ xf86PciProbe(void)
                     primaryBus.id.pci = info;
                 }
                 else {
-                    xf86Msg(X_NOTICE,
-                            "More than one possible primary device found\n");
-                    primaryBus.type ^= (BusType) (-1);
+		    /* 
+		     * Ok, we found more than one possible primary device with this heuristic
+		     * Now also check if IO is enabled.
+		     */
+		    int j;
+
+		    primaryBus.type = BUS_NONE;
+		    for (j = 0; j < num; j++) {
+			    info = xf86PciVideoInfo[j];
+			    pci_device_cfg_read_u16(info, & command, 4);
+
+			    if ((command & PCI_CMD_MEM_ENABLE)
+					    && (command & PCI_CMD_IO_ENABLE)
+					    && (IS_VGA(info->device_class))) {
+				    if (primaryBus.type == BUS_NONE) {
+					    primaryBus.type = BUS_PCI;
+					    primaryBus.id.pci = info;
+				    } else {
+					    primaryBus.type = BUS_NONE;
+					    for (j = 0; j < num; j++) {
+						    info = xf86PciVideoInfo[j];
+						    pci_device_cfg_read_u16(info, & command, 4);
+
+						    if ((command & PCI_CMD_MEM_ENABLE)
+								    && (command & PCI_CMD_IO_ENABLE)
+								    && (IS_VGA(info->device_class))
+								    && info->rom_size) {
+							    if (primaryBus.type == BUS_NONE) {
+								    primaryBus.type = BUS_PCI;
+								    primaryBus.id.pci = info;
+							    } else {
+								    xf86Msg(X_NOTICE,
+										    "More than one possible primary device found\n");
+								    primaryBus.type ^= (BusType)(-1);
+								    break;
+							    }
+						    }
+					    }
+					    break;
+				    }
+			    }
+		    }
+		    break;
+
                 }
             }
         }