Index: sys/amd64/acpica/acpi_machdep.c
===================================================================
--- sys/amd64/acpica/acpi_machdep.c
+++ sys/amd64/acpica/acpi_machdep.c
@@ -381,4 +381,5 @@
 DEFINE_CLASS_1(nexus, nexus_acpi_driver, nexus_acpi_methods, 1, nexus_driver);
 static devclass_t nexus_devclass;
 
-DRIVER_MODULE(nexus_acpi, root, nexus_acpi_driver, nexus_devclass, 0, 0);
+EARLY_DRIVER_MODULE(nexus_acpi, root, nexus_acpi_driver, nexus_devclass, 0, 0,
+    BUS_PASS_BUS);
Index: sys/dev/acpica/acpi.c
===================================================================
--- sys/dev/acpica/acpi.c
+++ sys/dev/acpica/acpi.c
@@ -228,7 +228,8 @@
 };
 
 static devclass_t acpi_devclass;
-DRIVER_MODULE(acpi, nexus, acpi_driver, acpi_devclass, acpi_modevent, 0);
+EARLY_DRIVER_MODULE(acpi, nexus, acpi_driver, acpi_devclass, acpi_modevent, 0,
+    BUS_PASS_BUS);
 MODULE_VERSION(acpi, 1);
 
 ACPI_SERIAL_DECL(acpi, "ACPI root bus");
Index: sys/dev/acpica/acpi_cpu.c
===================================================================
--- sys/dev/acpica/acpi_cpu.c
+++ sys/dev/acpica/acpi_cpu.c
@@ -211,7 +211,8 @@
 };
 
 static devclass_t acpi_cpu_devclass;
-DRIVER_MODULE(cpu, acpi, acpi_cpu_driver, acpi_cpu_devclass, 0, 0);
+EARLY_DRIVER_MODULE(cpu, acpi, acpi_cpu_driver, acpi_cpu_devclass, 0, 0,
+    BUS_PASS_CPU);
 MODULE_DEPEND(cpu, acpi, 1, 1, 1);
 
 static int
Index: sys/dev/acpica/acpi_hpet.c
===================================================================
--- sys/dev/acpica/acpi_hpet.c
+++ sys/dev/acpica/acpi_hpet.c
@@ -861,5 +861,5 @@
 	sizeof(struct hpet_softc),
 };
 
-DRIVER_MODULE(hpet, acpi, hpet_driver, hpet_devclass, 0, 0);
+EARLY_DRIVER_MODULE(hpet, acpi, hpet_driver, hpet_devclass, 0, 0, BUS_PASS_TIMER);
 MODULE_DEPEND(hpet, acpi, 1, 1, 1);
Index: sys/dev/acpica/acpi_isab.c
===================================================================
--- sys/dev/acpica/acpi_isab.c
+++ sys/dev/acpica/acpi_isab.c
@@ -85,7 +85,8 @@
 	sizeof(struct acpi_isab_softc),
 };
 
-DRIVER_MODULE(acpi_isab, acpi, acpi_isab_driver, isab_devclass, 0, 0);
+EARLY_DRIVER_MODULE(acpi_isab, acpi, acpi_isab_driver, isab_devclass, 0, 0,
+    BUS_PASS_BUS);
 MODULE_DEPEND(acpi_isab, acpi, 1, 1, 1);
 
 static int
Index: sys/dev/acpica/acpi_pci.c
===================================================================
--- sys/dev/acpica/acpi_pci.c
+++ sys/dev/acpica/acpi_pci.c
@@ -105,7 +105,8 @@
 
 DEFINE_CLASS_1(pci, acpi_pci_driver, acpi_pci_methods, sizeof(struct pci_softc),
     pci_driver);
-DRIVER_MODULE(acpi_pci, pcib, acpi_pci_driver, pci_devclass, 0, 0);
+EARLY_DRIVER_MODULE(acpi_pci, pcib, acpi_pci_driver, pci_devclass, 0, 0,
+    BUS_PASS_BUS);
 MODULE_DEPEND(acpi_pci, acpi, 1, 1, 1);
 MODULE_DEPEND(acpi_pci, pci, 1, 1, 1);
 MODULE_VERSION(acpi_pci, 1);
Index: sys/dev/acpica/acpi_pci_link.c
===================================================================
--- sys/dev/acpica/acpi_pci_link.c
+++ sys/dev/acpica/acpi_pci_link.c
@@ -1118,6 +1118,6 @@
 
 static devclass_t pci_link_devclass;
 
-DRIVER_MODULE(acpi_pci_link, acpi, acpi_pci_link_driver, pci_link_devclass, 0,
-    0);
+EARLY_DRIVER_MODULE(acpi_pci_link, acpi, acpi_pci_link_driver,
+    pci_link_devclass, 0, 0, BUS_PASS_BUS);
 MODULE_DEPEND(acpi_pci_link, acpi, 1, 1, 1);
Index: sys/dev/acpica/acpi_pcib_acpi.c
===================================================================
--- sys/dev/acpica/acpi_pcib_acpi.c
+++ sys/dev/acpica/acpi_pcib_acpi.c
@@ -150,7 +150,8 @@
 
 DEFINE_CLASS_0(pcib, acpi_pcib_acpi_driver, acpi_pcib_acpi_methods,
     sizeof(struct acpi_hpcib_softc));
-DRIVER_MODULE(acpi_pcib, acpi, acpi_pcib_acpi_driver, pcib_devclass, 0, 0);
+EARLY_DRIVER_MODULE(acpi_pcib, acpi, acpi_pcib_acpi_driver, pcib_devclass,
+    0, 0, BUS_PASS_BUS);
 MODULE_DEPEND(acpi_pcib, acpi, 1, 1, 1);
 
 static int
Index: sys/dev/acpica/acpi_pcib_pci.c
===================================================================
--- sys/dev/acpica/acpi_pcib_pci.c
+++ sys/dev/acpica/acpi_pcib_pci.c
@@ -90,7 +90,8 @@
 
 DEFINE_CLASS_1(pcib, acpi_pcib_pci_driver, acpi_pcib_pci_methods,
     sizeof(struct acpi_pcib_softc), pcib_driver);
-DRIVER_MODULE(acpi_pcib, pci, acpi_pcib_pci_driver, pcib_devclass, 0, 0);
+EARLY_DRIVER_MODULE(acpi_pcib, pci, acpi_pcib_pci_driver, pcib_devclass, 0, 0,
+    BUS_PASS_BUS);
 MODULE_DEPEND(acpi_pcib, acpi, 1, 1, 1);
 
 static int
Index: sys/dev/acpica/acpi_resource.c
===================================================================
--- sys/dev/acpica/acpi_resource.c
+++ sys/dev/acpica/acpi_resource.c
@@ -646,8 +646,8 @@
 };
 
 static devclass_t acpi_sysres_devclass;
-DRIVER_MODULE(acpi_sysresource, acpi, acpi_sysres_driver, acpi_sysres_devclass,
-    0, 0);
+EARLY_DRIVER_MODULE(acpi_sysresource, acpi, acpi_sysres_driver,
+    acpi_sysres_devclass, 0, 0, BUS_PASS_RESOURCE);
 MODULE_DEPEND(acpi_sysresource, acpi, 1, 1, 1);
 
 static int
Index: sys/dev/pci/hostb_pci.c
===================================================================
--- sys/dev/pci/hostb_pci.c
+++ sys/dev/pci/hostb_pci.c
@@ -264,4 +264,5 @@
 
 static devclass_t pci_hostb_devclass;
 
-DRIVER_MODULE(hostb, pci, pci_hostb_driver, pci_hostb_devclass, 0, 0);
+EARLY_DRIVER_MODULE(hostb, pci, pci_hostb_driver, pci_hostb_devclass, 0, 0,
+    BUS_PASS_BUS);
Index: sys/dev/pci/pci.c
===================================================================
--- sys/dev/pci/pci.c
+++ sys/dev/pci/pci.c
@@ -193,7 +193,8 @@
 DEFINE_CLASS_0(pci, pci_driver, pci_methods, sizeof(struct pci_softc));
 
 static devclass_t pci_devclass;
-DRIVER_MODULE(pci, pcib, pci_driver, pci_devclass, pci_modevent, NULL);
+EARLY_DRIVER_MODULE(pci, pcib, pci_driver, pci_devclass, pci_modevent, NULL,
+    BUS_PASS_BUS);
 MODULE_VERSION(pci, 1);
 
 static char	*pci_vendordata;
Index: sys/dev/pci/pci_pci.c
===================================================================
--- sys/dev/pci/pci_pci.c
+++ sys/dev/pci/pci_pci.c
@@ -111,7 +111,8 @@
 static devclass_t pcib_devclass;
 
 DEFINE_CLASS_0(pcib, pcib_driver, pcib_methods, sizeof(struct pcib_softc));
-DRIVER_MODULE(pcib, pci, pcib_driver, pcib_devclass, NULL, NULL);
+EARLY_DRIVER_MODULE(pcib, pci, pcib_driver, pcib_devclass, NULL, NULL,
+    BUS_PASS_BUS);
 
 #ifdef NEW_PCIB
 SYSCTL_DECL(_hw_pci);
Index: sys/dev/pci/vga_pci.c
===================================================================
--- sys/dev/pci/vga_pci.c
+++ sys/dev/pci/vga_pci.c
@@ -600,4 +600,5 @@
 
 static devclass_t vga_devclass;
 
-DRIVER_MODULE(vgapci, pci, vga_pci_driver, vga_devclass, 0, 0);
+EARLY_DRIVER_MODULE(vgapci, pci, vga_pci_driver, vga_devclass, 0, 0,
+    BUS_PASS_BUS);
Index: sys/i386/acpica/acpi_machdep.c
===================================================================
--- sys/i386/acpica/acpi_machdep.c
+++ sys/i386/acpica/acpi_machdep.c
@@ -391,4 +391,5 @@
 DEFINE_CLASS_1(nexus, nexus_acpi_driver, nexus_acpi_methods, 1, nexus_driver);
 static devclass_t nexus_devclass;
 
-DRIVER_MODULE(nexus_acpi, root, nexus_acpi_driver, nexus_devclass, 0, 0);
+EARLY_DRIVER_MODULE(nexus_acpi, root, nexus_acpi_driver, nexus_devclass, 0, 0,
+    BUS_PASS_BUS);
Index: sys/powerpc/ofw/ofw_pcib_pci.c
===================================================================
--- sys/powerpc/ofw/ofw_pcib_pci.c
+++ sys/powerpc/ofw/ofw_pcib_pci.c
@@ -83,7 +83,8 @@
 
 DEFINE_CLASS_1(pcib, ofw_pcib_pci_driver, ofw_pcib_pci_methods,
     sizeof(struct ofw_pcib_softc), pcib_driver);
-DRIVER_MODULE(ofw_pcib, pci, ofw_pcib_pci_driver, pcib_devclass, 0, 0);
+EARLY_DRIVER_MODULE(ofw_pcib, pci, ofw_pcib_pci_driver, pcib_devclass, 0, 0,
+    BUS_PASS_BUS);
 
 static int
 ofw_pcib_pci_probe(device_t dev)
Index: sys/powerpc/ofw/ofw_pcibus.c
===================================================================
--- sys/powerpc/ofw/ofw_pcibus.c
+++ sys/powerpc/ofw/ofw_pcibus.c
@@ -93,7 +93,8 @@
 
 DEFINE_CLASS_1(pci, ofw_pcibus_driver, ofw_pcibus_methods,
     sizeof(struct pci_softc), pci_driver);
-DRIVER_MODULE(ofw_pcibus, pcib, ofw_pcibus_driver, pci_devclass, 0, 0);
+EARLY_DRIVER_MODULE(ofw_pcibus, pcib, ofw_pcibus_driver, pci_devclass, 0, 0,
+    BUS_PASS_BUS);
 MODULE_VERSION(ofw_pcibus, 1);
 MODULE_DEPEND(ofw_pcibus, pci, 1, 1, 1);
 
Index: sys/powerpc/ofw/openpic_ofw.c
===================================================================
--- sys/powerpc/ofw/openpic_ofw.c
+++ sys/powerpc/ofw/openpic_ofw.c
@@ -93,9 +93,12 @@
 	sizeof(struct openpic_softc),
 };
 
-DRIVER_MODULE(openpic, ofwbus, openpic_ofw_driver, openpic_devclass, 0, 0);
-DRIVER_MODULE(openpic, simplebus, openpic_ofw_driver, openpic_devclass, 0, 0);
-DRIVER_MODULE(openpic, macio, openpic_ofw_driver, openpic_devclass, 0, 0);
+EARLY_DRIVER_MODULE(openpic, ofwbus, openpic_ofw_driver, openpic_devclass,
+    0, 0, BUS_PASS_INTERRUPT);
+EARLY_DRIVER_MODULE(openpic, simplebus, openpic_ofw_driver, openpic_devclass,
+    0, 0, BUS_PASS_INTERRUPT);
+EARLY_DRIVER_MODULE(openpic, macio, openpic_ofw_driver, openpic_devclass, 0, 0,
+    BUS_PASS_INTERRUPT);
 
 static int
 openpic_ofw_probe(device_t dev)
Index: sys/powerpc/powermac/cpcht.c
===================================================================
--- sys/powerpc/powermac/cpcht.c
+++ sys/powerpc/powermac/cpcht.c
@@ -135,7 +135,8 @@
 static devclass_t	cpcht_devclass;
 DEFINE_CLASS_1(pcib, cpcht_driver, cpcht_methods, sizeof(struct cpcht_softc),
     ofw_pci_driver);
-DRIVER_MODULE(cpcht, ofwbus, cpcht_driver, cpcht_devclass, 0, 0);
+EARLY_DRIVER_MODULE(cpcht, ofwbus, cpcht_driver, cpcht_devclass, 0, 0,
+    BUS_PASS_BUS);
 
 #define CPCHT_IOPORT_BASE	0xf4000000UL /* Hardwired */
 #define CPCHT_IOPORT_SIZE	0x00400000UL
@@ -541,7 +542,8 @@
 	sizeof(struct openpic_cpcht_softc),
 };
 
-DRIVER_MODULE(openpic, unin, openpic_cpcht_driver, openpic_devclass, 0, 0);
+EARLY_DRIVER_MODULE(openpic, unin, openpic_cpcht_driver, openpic_devclass,
+    0, 0, BUS_PASS_INTERRUPT);
 
 static int
 openpic_cpcht_probe(device_t dev)
Index: sys/powerpc/powermac/macgpio.c
===================================================================
--- sys/powerpc/powermac/macgpio.c
+++ sys/powerpc/powermac/macgpio.c
@@ -124,7 +124,8 @@
 
 devclass_t macgpio_devclass;
 
-DRIVER_MODULE(macgpio, macio, macgpio_pci_driver, macgpio_devclass, 0, 0);
+EARLY_DRIVER_MODULE(macgpio, macio, macgpio_pci_driver, macgpio_devclass, 0, 0,
+    BUS_PASS_BUS);
 
 struct macgpio_devinfo {
 	struct ofw_bus_devinfo mdi_obdinfo;
Index: sys/powerpc/powermac/macio.c
===================================================================
--- sys/powerpc/powermac/macio.c
+++ sys/powerpc/powermac/macio.c
@@ -133,7 +133,8 @@
 
 devclass_t macio_devclass;
 
-DRIVER_MODULE(macio, pci, macio_pci_driver, macio_devclass, 0, 0);
+EARLY_DRIVER_MODULE(macio, pci, macio_pci_driver, macio_devclass, 0, 0,
+    BUS_PASS_BUS);
 
 /*
  * PCI ID search table
Index: sys/powerpc/powermac/pmu.c
===================================================================
--- sys/powerpc/powermac/pmu.c
+++ sys/powerpc/powermac/pmu.c
@@ -146,7 +146,8 @@
 
 static devclass_t pmu_devclass;
 
-DRIVER_MODULE(pmu, macio, pmu_driver, pmu_devclass, 0, 0);
+EARLY_DRIVER_MODULE(pmu, macio, pmu_driver, pmu_devclass, 0, 0,
+    BUS_PASS_RESOURCE);
 DRIVER_MODULE(adb, pmu, adb_driver, adb_devclass, 0, 0);
 
 static int	pmuextint_probe(device_t);
@@ -168,7 +169,8 @@
 
 static devclass_t pmuextint_devclass;
 
-DRIVER_MODULE(pmuextint, macgpio, pmuextint_driver, pmuextint_devclass, 0, 0);
+EARLY_DRIVER_MODULE(pmuextint, macgpio, pmuextint_driver, pmuextint_devclass,
+    0, 0, BUS_PASS_RESOURCE);
 
 /* Make sure uhid is loaded, as it turns off some of the ADB emulation */
 MODULE_DEPEND(pmu, usb, 1, 1, 1);
Index: sys/powerpc/powermac/uninorth.c
===================================================================
--- sys/powerpc/powermac/uninorth.c
+++ sys/powerpc/powermac/uninorth.c
@@ -143,7 +143,8 @@
  */
 static device_t		unin_chip;
 
-DRIVER_MODULE(unin, ofwbus, unin_chip_driver, unin_chip_devclass, 0, 0);
+EARLY_DRIVER_MODULE(unin, ofwbus, unin_chip_driver, unin_chip_devclass, 0, 0,
+    BUS_PASS_BUS);
 
 /*
  * Add an interrupt to the dev's resource list if present
Index: sys/powerpc/powermac/uninorthpci.c
===================================================================
--- sys/powerpc/powermac/uninorthpci.c
+++ sys/powerpc/powermac/uninorthpci.c
@@ -98,7 +98,8 @@
 
 DEFINE_CLASS_1(pcib, uninorth_driver, uninorth_methods,
     sizeof(struct uninorth_softc), ofw_pci_driver);
-DRIVER_MODULE(uninorth, ofwbus, uninorth_driver, uninorth_devclass, 0, 0);
+EARLY_DRIVER_MODULE(uninorth, ofwbus, uninorth_driver, uninorth_devclass, 0, 0,
+    BUS_PASS_BUS);
 
 static int
 uninorth_probe(device_t dev)