Index: drmP.h
===================================================================
diff --git a/head/sys/dev/drm2/drmP.h b/head/sys/dev/drm2/drmP.h
--- a/head/sys/dev/drm2/drmP.h	(revision 287125)
+++ b/head/sys/dev/drm2/drmP.h	(working copy)
@@ -1095,7 +1095,7 @@
 	char busid_str[128];
 	int modesetting;
 
-	drm_pci_id_list_t *id_entry;	/* PCI ID, name, and chipset private */
+	const drm_pci_id_list_t *id_entry;	/* PCI ID, name, and chipset private */
 };
 
 #define DRM_SWITCH_POWER_ON 0
@@ -1735,8 +1735,8 @@
 bool dmi_check_system(const struct dmi_system_id *);
 
 /* Device setup support (drm_drv.c) */
-int	drm_probe_helper(device_t kdev, drm_pci_id_list_t *idlist);
-int	drm_attach_helper(device_t kdev, drm_pci_id_list_t *idlist,
+int	drm_probe_helper(device_t kdev, const drm_pci_id_list_t *idlist);
+int	drm_attach_helper(device_t kdev, const drm_pci_id_list_t *idlist,
 	    struct drm_driver *driver);
 int	drm_generic_detach(device_t kdev);
 
Index: drm_os_freebsd.c
===================================================================
diff --git a/head/sys/dev/drm2/drm_os_freebsd.c b/head/sys/dev/drm2/drm_os_freebsd.c
--- a/head/sys/dev/drm2/drm_os_freebsd.c	(revision 287125)
+++ b/head/sys/dev/drm2/drm_os_freebsd.c	(working copy)
@@ -67,8 +67,8 @@
         return (tv);
 }
 
-static drm_pci_id_list_t *
-drm_find_description(int vendor, int device, drm_pci_id_list_t *idlist)
+static const drm_pci_id_list_t *
+drm_find_description(int vendor, int device, const drm_pci_id_list_t *idlist)
 {
 	int i = 0;
 
@@ -87,9 +87,9 @@
  * method.
  */
 int
-drm_probe_helper(device_t kdev, drm_pci_id_list_t *idlist)
+drm_probe_helper(device_t kdev, const drm_pci_id_list_t *idlist)
 {
-	drm_pci_id_list_t *id_entry;
+	const drm_pci_id_list_t *id_entry;
 	int vendor, device;
 
 	vendor = pci_get_vendor(kdev);
@@ -118,7 +118,7 @@
  * method.
  */
 int
-drm_attach_helper(device_t kdev, drm_pci_id_list_t *idlist,
+drm_attach_helper(device_t kdev, const drm_pci_id_list_t *idlist,
     struct drm_driver *driver)
 {
 	struct drm_device *dev;