diff --git a/sys/arm/mv/mv_pci.c b/sys/arm/mv/mv_pci.c
--- a/sys/arm/mv/mv_pci.c
+++ b/sys/arm/mv/mv_pci.c
@@ -916,11 +916,9 @@
 	case SYS_RES_IOPORT:
 	case SYS_RES_MEMORY:
 		break;
-#ifdef PCI_RES_BUS
 	case PCI_RES_BUS:
 		return (pci_domain_alloc_bus(sc->ap_segment, child, rid, start,
 		    end, count, flags));
-#endif
 	default:
 		return (BUS_ALLOC_RESOURCE(device_get_parent(dev), dev,
 		    type, rid, start, end, count, flags));
@@ -944,20 +942,16 @@
 mv_pcib_adjust_resource(device_t dev, device_t child, int type,
     struct resource *r, rman_res_t start, rman_res_t end)
 {
-#ifdef PCI_RES_BUS
 	struct mv_pcib_softc *sc = device_get_softc(dev);
-#endif
 
 	switch (type) {
 	case SYS_RES_IOPORT:
 	case SYS_RES_MEMORY:
 		return (bus_generic_rman_adjust_resource(dev, child, type, r,
 		    start, end));
-#ifdef PCI_RES_BUS
 	case PCI_RES_BUS:
 		return (pci_domain_adjust_bus(sc->ap_segment, child, r, start,
 		    end));
-#endif
 	default:
 		return (bus_generic_adjust_resource(dev, child, type, r,
 		    start, end));
@@ -968,19 +962,15 @@
 mv_pcib_release_resource(device_t dev, device_t child, int type, int rid,
     struct resource *res)
 {
-#ifdef PCI_RES_BUS
 	struct mv_pcib_softc *sc = device_get_softc(dev);
-#endif
 
 	switch (type) {
 	case SYS_RES_IOPORT:
 	case SYS_RES_MEMORY:
 		return (bus_generic_rman_release_resource(dev, child, type,
 		    rid, res));
-#ifdef PCI_RES_BUS
 	case PCI_RES_BUS:
 		return (pci_domain_release_bus(sc->ap_segment, child, rid, res));
-#endif
 	default:
 		return (BUS_RELEASE_RESOURCE(device_get_parent(dev), child,
 		    type, rid, res));
@@ -991,19 +981,15 @@
 mv_pcib_activate_resource(device_t dev, device_t child, int type, int rid,
     struct resource *r)
 {
-#ifdef PCI_RES_BUS
 	struct mv_pcib_softc *sc = device_get_softc(dev);
-#endif
 
 	switch (type) {
 	case SYS_RES_IOPORT:
 	case SYS_RES_MEMORY:
 		return (bus_generic_rman_activate_resource(dev, child, type,
 		    rid, r));
-#ifdef PCI_RES_BUS
 	case PCI_RES_BUS:
 		return (pci_domain_activate_bus(sc->ap_segment, child, rid, r));
-#endif
 	default:
 		return (bus_generic_activate_resource(dev, child, type, rid,
 		    r));
@@ -1014,20 +1000,16 @@
 mv_pcib_deactivate_resource(device_t dev, device_t child, int type, int rid,
     struct resource *r)
 {
-#ifdef PCI_RES_BUS
 	struct mv_pcib_softc *sc = device_get_softc(dev);
-#endif
 
 	switch (type) {
 	case SYS_RES_IOPORT:
 	case SYS_RES_MEMORY:
 		return (bus_generic_rman_deactivate_resource(dev, child, type,
 		    rid, r));
-#ifdef PCI_RES_BUS
 	case PCI_RES_BUS:
 		return (pci_domain_deactivate_bus(sc->ap_segment, child, rid,
 		    r));
-#endif
 	default:
 		return (bus_generic_deactivate_resource(dev, child, type, rid,
 		    r));
diff --git a/sys/arm64/cavium/thunder_pcie_pem.c b/sys/arm64/cavium/thunder_pcie_pem.c
--- a/sys/arm64/cavium/thunder_pcie_pem.c
+++ b/sys/arm64/cavium/thunder_pcie_pem.c
@@ -257,16 +257,12 @@
 thunder_pem_activate_resource(device_t dev, device_t child, int type, int rid,
     struct resource *r)
 {
-#if defined(PCI_RES_BUS)
 	struct thunder_pem_softc *sc;
 
 	sc = device_get_softc(dev);
-#endif
 	switch (type) {
-#if defined(PCI_RES_BUS)
 	case PCI_RES_BUS:
 		return (pci_domain_activate_bus(sc->id, child, rid, r));
-#endif
 	case SYS_RES_MEMORY:
 	case SYS_RES_IOPORT:
 		return (bus_generic_rman_activate_resource(dev, child, type,
@@ -281,16 +277,12 @@
 thunder_pem_deactivate_resource(device_t dev, device_t child, int type, int rid,
     struct resource *r)
 {
-#if defined(PCI_RES_BUS)
 	struct thunder_pem_softc *sc;
 
 	sc = device_get_softc(dev);
-#endif
 	switch (type) {
-#if defined(PCI_RES_BUS)
 	case PCI_RES_BUS:
 		return (pci_domain_deactivate_bus(sc->id, child, rid, r));
-#endif
 	case SYS_RES_MEMORY:
 	case SYS_RES_IOPORT:
 		return (bus_generic_rman_deactivate_resource(dev, child, type,
@@ -358,16 +350,12 @@
 thunder_pem_adjust_resource(device_t dev, device_t child, int type,
     struct resource *res, rman_res_t start, rman_res_t end)
 {
-#if defined(PCI_RES_BUS)
 	struct thunder_pem_softc *sc;
 
 	sc = device_get_softc(dev);
-#endif
 	switch (type) {
-#if defined(PCI_RES_BUS)
 	case PCI_RES_BUS:
 		return (pci_domain_adjust_bus(sc->id, child, res, start, end));
-#endif
 	case SYS_RES_MEMORY:
 	case SYS_RES_IOPORT:
 		return (bus_generic_rman_adjust_resource(dev, child, type, res,
@@ -679,11 +667,9 @@
 	device_t parent_dev;
 
 	switch (type) {
-#if defined(PCI_RES_BUS)
 	case PCI_RES_BUS:
 		return (pci_domain_alloc_bus(sc->id, child, rid, start,  end,
 		    count, flags));
-#endif
 	case SYS_RES_IOPORT:
 	case SYS_RES_MEMORY:
 		break;
@@ -727,15 +713,11 @@
     struct resource *res)
 {
 	device_t parent_dev;
-#if defined(PCI_RES_BUS)
 	struct thunder_pem_softc *sc = device_get_softc(dev);
-#endif
 
 	switch (type) {
-#if defined(PCI_RES_BUS)
 	case PCI_RES_BUS:
 		return (pci_domain_release_bus(sc->id, child, rid, res));
-#endif
 	case SYS_RES_MEMORY:
 	case SYS_RES_IOPORT:
 		return (bus_generic_rman_release_resource(dev, child, type,
diff --git a/sys/dev/acpica/acpi_pcib_acpi.c b/sys/dev/acpica/acpi_pcib_acpi.c
--- a/sys/dev/acpica/acpi_pcib_acpi.c
+++ b/sys/dev/acpica/acpi_pcib_acpi.c
@@ -96,7 +96,6 @@
 static int		acpi_pcib_acpi_adjust_resource(device_t dev,
 			    device_t child, int type, struct resource *r,
 			    rman_res_t start, rman_res_t end);
-#ifdef PCI_RES_BUS
 static int		acpi_pcib_acpi_release_resource(device_t dev,
 			    device_t child, int type, int rid,
 			    struct resource *r);
@@ -106,7 +105,6 @@
 static int		acpi_pcib_acpi_deactivate_resource(device_t dev,
 			    device_t child, int type, int rid,
 			    struct resource *r);
-#endif
 static int		acpi_pcib_request_feature(device_t pcib, device_t dev,
 			    enum pci_feature feature);
 static bus_dma_tag_t	acpi_pcib_get_dma_tag(device_t bus, device_t child);
@@ -124,15 +122,9 @@
     DEVMETHOD(bus_write_ivar,		acpi_pcib_write_ivar),
     DEVMETHOD(bus_alloc_resource,	acpi_pcib_acpi_alloc_resource),
     DEVMETHOD(bus_adjust_resource,	acpi_pcib_acpi_adjust_resource),
-#if defined(PCI_RES_BUS)
     DEVMETHOD(bus_release_resource,	acpi_pcib_acpi_release_resource),
     DEVMETHOD(bus_activate_resource,	acpi_pcib_acpi_activate_resource),
     DEVMETHOD(bus_deactivate_resource,	acpi_pcib_acpi_deactivate_resource),
-#else
-    DEVMETHOD(bus_release_resource,	bus_generic_release_resource),
-    DEVMETHOD(bus_activate_resource,	bus_generic_activate_resource),
-    DEVMETHOD(bus_deactivate_resource,	bus_generic_deactivate_resource),
-#endif
     DEVMETHOD(bus_setup_intr,		bus_generic_setup_intr),
     DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
     DEVMETHOD(bus_get_cpus,		acpi_pcib_get_cpus),
@@ -246,11 +238,9 @@
 		case ACPI_IO_RANGE:
 			type = SYS_RES_IOPORT;
 			break;
-#ifdef PCI_RES_BUS
 		case ACPI_BUS_NUMBER_RANGE:
 			type = PCI_RES_BUS;
 			break;
-#endif
 		default:
 			return (AE_OK);
 		}
@@ -285,7 +275,6 @@
 	return (AE_OK);
 }
 
-#if defined(PCI_RES_BUS)
 static bool
 get_decoded_bus_range(struct acpi_hpcib_softc *sc, rman_res_t *startp,
     rman_res_t *endp)
@@ -299,7 +288,6 @@
 	*endp = rle->end;
 	return (true);
 }
-#endif
 
 static int
 acpi_pcib_osc(struct acpi_hpcib_softc *sc, uint32_t osc_ctl)
@@ -364,11 +352,9 @@
     ACPI_STATUS			status;
     static int bus0_seen = 0;
     u_int slot, func, busok;
-#if defined(PCI_RES_BUS)
     struct resource *bus_res;
     rman_res_t end, start;
     int rid;
-#endif
     int error, domain;
     uint8_t busno;
 
@@ -482,7 +468,6 @@
 	}
     }
 
-#if defined(PCI_RES_BUS)
     /*
      * If nothing else worked, hope that ACPI at least lays out the
      * Host-PCI bridges in order and that as a result the next free
@@ -527,18 +512,6 @@
 		    }
 	    }
     }
-#else
-    /*
-     * If nothing else worked, hope that ACPI at least lays out the
-     * host-PCI bridges in order and that as a result our unit number
-     * is actually our bus number.  There are several reasons this
-     * might not be true.
-     */
-    if (busok == 0) {
-	sc->ap_bus = device_get_unit(dev);
-	device_printf(dev, "trying bus number %d\n", sc->ap_bus);
-    }
-#endif
 
     /* If this is bus 0 on segment 0, note that it has been seen already. */
     if (sc->ap_segment == 0 && sc->ap_bus == 0)
@@ -569,9 +542,7 @@
 
 errout:
     device_printf(device_get_parent(dev), "couldn't attach pci bus\n");
-#if defined(PCI_RES_BUS)
     pcib_host_res_free(dev, &sc->ap_host_res);
-#endif
     return (error);
 }
 
@@ -703,11 +674,9 @@
 #endif
 
     sc = device_get_softc(dev);
-#ifdef PCI_RES_BUS
     if (type == PCI_RES_BUS)
 	return (pci_domain_alloc_bus(sc->ap_segment, child, rid, start, end,
 	    count, flags));
-#endif
     res = pcib_host_res_alloc(&sc->ap_host_res, child, type, rid, start, end,
 	count, flags);
 
@@ -731,16 +700,13 @@
 	struct acpi_hpcib_softc *sc;
 
 	sc = device_get_softc(dev);
-#ifdef PCI_RES_BUS
 	if (type == PCI_RES_BUS)
 		return (pci_domain_adjust_bus(sc->ap_segment, child, r, start,
 		    end));
-#endif
 	return (pcib_host_res_adjust(&sc->ap_host_res, child, type, r, start,
 	    end));
 }
 
-#ifdef PCI_RES_BUS
 int
 acpi_pcib_acpi_release_resource(device_t dev, device_t child, int type, int rid,
     struct resource *r)
@@ -777,7 +743,6 @@
 		    r));
 	return (bus_generic_deactivate_resource(dev, child, type, rid, r));
 }
-#endif
 
 static int
 acpi_pcib_request_feature(device_t pcib, device_t dev, enum pci_feature feature)
diff --git a/sys/dev/cardbus/cardbus.c b/sys/dev/cardbus/cardbus.c
--- a/sys/dev/cardbus/cardbus.c
+++ b/sys/dev/cardbus/cardbus.c
@@ -93,13 +93,10 @@
 cardbus_attach(device_t cbdev)
 {
 	struct cardbus_softc *sc;
-#ifdef PCI_RES_BUS
 	int rid;
-#endif
 
 	sc = device_get_softc(cbdev);
 	sc->sc_dev = cbdev;
-#ifdef PCI_RES_BUS
 	rid = 0;
 	sc->sc_bus = bus_alloc_resource(cbdev, PCI_RES_BUS, &rid,
 	    pcib_get_bus(cbdev), pcib_get_bus(cbdev), 1, 0);
@@ -107,25 +104,18 @@
 		device_printf(cbdev, "failed to allocate bus number\n");
 		return (ENXIO);
 	}
-#else
-	device_printf(cbdev, "Your bus numbers may be AFU\n");
-#endif
 	return (0);
 }
 
 static int
 cardbus_detach(device_t cbdev)
 {
-#ifdef PCI_RES_BUS
 	struct cardbus_softc *sc;
-#endif
 
 	cardbus_detach_card(cbdev);
-#ifdef PCI_RES_BUS
 	sc = device_get_softc(cbdev);
 	device_printf(cbdev, "Freeing up the allocatd bus\n");
 	(void)bus_release_resource(cbdev, PCI_RES_BUS, 0, sc->sc_bus);
-#endif
 	return (0);
 }
 
diff --git a/sys/dev/cardbus/cardbusvar.h b/sys/dev/cardbus/cardbusvar.h
--- a/sys/dev/cardbus/cardbusvar.h
+++ b/sys/dev/cardbus/cardbusvar.h
@@ -68,9 +68,7 @@
 struct cardbus_softc 
 {
 	device_t	sc_dev;
-#ifdef PCI_RES_BUS
 	struct resource *sc_bus;
-#endif
 };
 
 /*
diff --git a/sys/dev/ofw/ofw_pcib.c b/sys/dev/ofw/ofw_pcib.c
--- a/sys/dev/ofw/ofw_pcib.c
+++ b/sys/dev/ofw/ofw_pcib.c
@@ -424,17 +424,13 @@
 ofw_pcib_alloc_resource(device_t bus, device_t child, int type, int *rid,
     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
 {
-#if defined(PCI_RES_BUS)
 	struct ofw_pci_softc *sc;
 
 	sc = device_get_softc(bus);
-#endif
 	switch (type) {
-#if defined(PCI_RES_BUS)
 	case PCI_RES_BUS:
 		return (pci_domain_alloc_bus(sc->sc_pci_domain, child, rid,
 		    start, end, count, flags));
-#endif
 	case SYS_RES_MEMORY:
 	case SYS_RES_IOPORT:
 		return (bus_generic_rman_alloc_resource(bus, child, type, rid,
@@ -449,17 +445,13 @@
 ofw_pcib_release_resource(device_t bus, device_t child, int type, int rid,
     struct resource *res)
 {
-#if defined(PCI_RES_BUS)
 	struct ofw_pci_softc *sc;
 
 	sc = device_get_softc(bus);
-#endif
 	switch (type) {
-#if defined(PCI_RES_BUS)
 	case PCI_RES_BUS:
 		return (pci_domain_release_bus(sc->sc_pci_domain, child, rid,
 		    res));
-#endif
 	case SYS_RES_MEMORY:
 	case SYS_RES_IOPORT:
 		return (bus_generic_rman_release_resource(bus, child, type, rid,
@@ -513,17 +505,13 @@
 ofw_pcib_activate_resource(device_t bus, device_t child, int type, int rid,
     struct resource *res)
 {
-#if defined(PCI_RES_BUS)
 	struct ofw_pci_softc *sc;
 
 	sc = device_get_softc(bus);
-#endif
 	switch (type) {
-#if defined(PCI_RES_BUS)
 	case PCI_RES_BUS:
 		return (pci_domain_activate_bus(sc->sc_pci_domain, child, rid,
 		    res));
-#endif
 	case SYS_RES_MEMORY:
 	case SYS_RES_IOPORT:
 		return (bus_generic_rman_activate_resource(bus, child, type, rid,
@@ -634,17 +622,13 @@
 ofw_pcib_deactivate_resource(device_t bus, device_t child, int type, int rid,
     struct resource *res)
 {
-#if defined(PCI_RES_BUS)
 	struct ofw_pci_softc *sc;
 
 	sc = device_get_softc(bus);
-#endif
 	switch (type) {
-#if defined(PCI_RES_BUS)
 	case PCI_RES_BUS:
 		return (pci_domain_deactivate_bus(sc->sc_pci_domain, child, rid,
 		    res));
-#endif
 	case SYS_RES_MEMORY:
 	case SYS_RES_IOPORT:
 		return (bus_generic_rman_deactivate_resource(bus, child, type,
@@ -659,17 +643,13 @@
 ofw_pcib_adjust_resource(device_t bus, device_t child, int type,
     struct resource *res, rman_res_t start, rman_res_t end)
 {
-#if defined(PCI_RES_BUS)
 	struct ofw_pci_softc *sc;
 
 	sc = device_get_softc(bus);
-#endif
 	switch (type) {
-#if defined(PCI_RES_BUS)
 	case PCI_RES_BUS:
 		return (pci_domain_adjust_bus(sc->sc_pci_domain, child, res,
 		    start, end));
-#endif
 	case SYS_RES_MEMORY:
 	case SYS_RES_IOPORT:
 		return (bus_generic_rman_adjust_resource(bus, child, type, res,
diff --git a/sys/dev/pccbb/pccbb_pci.c b/sys/dev/pccbb/pccbb_pci.c
--- a/sys/dev/pccbb/pccbb_pci.c
+++ b/sys/dev/pccbb/pccbb_pci.c
@@ -276,10 +276,6 @@
 static int
 cbb_pci_attach(device_t brdev)
 {
-#if !defined(PCI_RES_BUS)
-	static int curr_bus_number = 2; /* XXX EVILE BAD (see below) */
-	uint32_t pribus;
-#endif
 	struct cbb_softc *sc = (struct cbb_softc *)device_get_softc(brdev);
 	struct sysctl_ctx_list *sctx;
 	struct sysctl_oid *soid;
@@ -293,13 +289,8 @@
 	sc->cbdev = NULL;
 	sc->domain = pci_get_domain(brdev);
 	sc->pribus = pcib_get_bus(parent);
-#if defined(PCI_RES_BUS)
 	pci_write_config(brdev, PCIR_PRIBUS_2, sc->pribus, 1);
 	pcib_setup_secbus(brdev, &sc->bus, 1);
-#else
-	sc->bus.sec = pci_read_config(brdev, PCIR_SECBUS_2, 1);
-	sc->bus.sub = pci_read_config(brdev, PCIR_SUBBUS_2, 1);
-#endif
 	SLIST_INIT(&sc->rl);
 
 	rid = CBBR_SOCKBASE;
@@ -351,32 +342,6 @@
 	    CTLFLAG_RD, &sc->subbus, 0, "io range 2 open");
 #endif
 
-#if !defined(PCI_RES_BUS)
-	/*
-	 * This is a gross hack.  We should be scanning the entire pci
-	 * tree, assigning bus numbers in a way such that we (1) can
-	 * reserve 1 extra bus just in case and (2) all sub buses
-	 * are in an appropriate range.
-	 */
-	DEVPRINTF((brdev, "Secondary bus is %d\n", sc->bus.sec));
-	pribus = pci_read_config(brdev, PCIR_PRIBUS_2, 1);
-	if (sc->bus.sec == 0 || sc->pribus != pribus) {
-		if (curr_bus_number <= sc->pribus)
-			curr_bus_number = sc->pribus + 1;
-		if (pribus != sc->pribus) {
-			DEVPRINTF((brdev, "Setting primary bus to %d\n",
-			    sc->pribus));
-			pci_write_config(brdev, PCIR_PRIBUS_2, sc->pribus, 1);
-		}
-		sc->bus.sec = curr_bus_number++;
-		sc->bus.sub = curr_bus_number++;
-		DEVPRINTF((brdev, "Secondary bus set to %d subbus %d\n",
-		    sc->bus.sec, sc->bus.sub));
-		pci_write_config(brdev, PCIR_SECBUS_2, sc->bus.sec, 1);
-		pci_write_config(brdev, PCIR_SUBBUS_2, sc->bus.sub, 1);
-	}
-#endif
-
 	/* Map and establish the interrupt. */
 	rid = 0;
 	sc->irq_res = bus_alloc_resource_any(brdev, SYS_RES_IRQ, &rid,
@@ -429,16 +394,12 @@
 static int
 cbb_pci_detach(device_t brdev)
 {
-#if defined(PCI_RES_BUS)
 	struct cbb_softc *sc = device_get_softc(brdev);
-#endif
 	int error;
 
 	error = cbb_detach(brdev);
-#if defined(PCI_RES_BUS)
 	if (error == 0)
 		pcib_free_secbus(brdev, &sc->bus);
-#endif
 	return (error);
 }
 
@@ -787,7 +748,6 @@
 	return retval;
 }
 
-#if defined(PCI_RES_BUS)
 static struct resource *
 cbb_pci_alloc_resource(device_t bus, device_t child, int type, int *rid,
     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
@@ -837,7 +797,6 @@
 	}
 	return (cbb_release_resource(bus, child, type, rid, r));
 }
-#endif
 
 /************************************************************************/
 /* PCI compat methods							*/
@@ -932,14 +891,9 @@
 	/* bus methods */
 	DEVMETHOD(bus_read_ivar,		cbb_read_ivar),
 	DEVMETHOD(bus_write_ivar,		cbb_write_ivar),
-#if defined(PCI_RES_BUS)
 	DEVMETHOD(bus_alloc_resource,		cbb_pci_alloc_resource),
 	DEVMETHOD(bus_adjust_resource,		cbb_pci_adjust_resource),
 	DEVMETHOD(bus_release_resource,		cbb_pci_release_resource),
-#else
-	DEVMETHOD(bus_alloc_resource,		cbb_alloc_resource),
-	DEVMETHOD(bus_release_resource,		cbb_release_resource),
-#endif
 	DEVMETHOD(bus_activate_resource,	cbb_activate_resource),
 	DEVMETHOD(bus_deactivate_resource,	cbb_deactivate_resource),
 	DEVMETHOD(bus_driver_added,		cbb_driver_added),
diff --git a/sys/dev/pci/pci.c b/sys/dev/pci/pci.c
--- a/sys/dev/pci/pci.c
+++ b/sys/dev/pci/pci.c
@@ -399,11 +399,9 @@
 SYSCTL_INT(_hw_pci, OID_AUTO, clear_bars, CTLFLAG_RDTUN, &pci_clear_bars, 0,
     "Ignore firmware-assigned resources for BARs.");
 
-#if defined(PCI_RES_BUS)
 static int pci_clear_buses;
 SYSCTL_INT(_hw_pci, OID_AUTO, clear_buses, CTLFLAG_RDTUN, &pci_clear_buses, 0,
     "Ignore firmware-assigned bus numbers.");
-#endif
 
 static int pci_enable_ari = 1;
 SYSCTL_INT(_hw_pci, OID_AUTO, enable_ari, CTLFLAG_RDTUN, &pci_enable_ari,
@@ -3700,7 +3698,6 @@
 	bus_release_resource(self, SYS_RES_MEMORY, rid, res);
 }
 
-#if defined(PCI_RES_BUS)
 static void
 pci_reserve_secbus(device_t bus, device_t dev, pcicfgregs *cfg,
     struct resource_list *rl)
@@ -3856,7 +3853,6 @@
 	return (resource_list_alloc(rl, dev, child, PCI_RES_BUS, rid, start,
 	    end, count, flags));
 }
-#endif
 
 static int
 pci_ea_bei_to_rid(device_t dev, int bei)
@@ -4112,13 +4108,11 @@
 			uhci_early_takeover(dev);
 	}
 
-#if defined(PCI_RES_BUS)
 	/*
 	 * Reserve resources for secondary bus ranges behind bridge
 	 * devices.
 	 */
 	pci_reserve_secbus(bus, dev, cfg, rl);
-#endif
 }
 
 static struct pci_devinfo *
@@ -4464,14 +4458,11 @@
 {
 	struct pci_softc *sc;
 	int busno, domain;
-#ifdef PCI_RES_BUS
 	int rid;
-#endif
 
 	sc = device_get_softc(dev);
 	domain = pcib_get_domain(dev);
 	busno = pcib_get_bus(dev);
-#ifdef PCI_RES_BUS
 	rid = 0;
 	sc->sc_bus = bus_alloc_resource(dev, PCI_RES_BUS, &rid, busno, busno,
 	    1, 0);
@@ -4479,7 +4470,6 @@
 		device_printf(dev, "failed to allocate bus number\n");
 		return (ENXIO);
 	}
-#endif
 	if (bootverbose)
 		device_printf(dev, "domain=%d, physical bus=%d\n",
 		    domain, busno);
@@ -4511,20 +4501,16 @@
 int
 pci_detach(device_t dev)
 {
-#ifdef PCI_RES_BUS
 	struct pci_softc *sc;
-#endif
 	int error;
 
 	error = bus_generic_detach(dev);
 	if (error)
 		return (error);
-#ifdef PCI_RES_BUS
 	sc = device_get_softc(dev);
 	error = bus_release_resource(dev, PCI_RES_BUS, 0, sc->sc_bus);
 	if (error)
 		return (error);
-#endif
 	return (device_delete_children(dev));
 }
 
@@ -5105,10 +5091,8 @@
 		pci_printf(&dinfo->cfg, "Device leaked memory resources\n");
 	if (resource_list_release_active(rl, dev, child, SYS_RES_IOPORT) != 0)
 		pci_printf(&dinfo->cfg, "Device leaked I/O resources\n");
-#ifdef PCI_RES_BUS
 	if (resource_list_release_active(rl, dev, child, PCI_RES_BUS) != 0)
 		pci_printf(&dinfo->cfg, "Device leaked PCI bus numbers\n");
-#endif
 
 	pci_cfg_save(child, dinfo, 1);
 }
@@ -5545,11 +5529,9 @@
 	rl = &dinfo->resources;
 	cfg = &dinfo->cfg;
 	switch (type) {
-#if defined(PCI_RES_BUS)
 	case PCI_RES_BUS:
 		return (pci_alloc_secbus(dev, child, rid, start, end, count,
 		    flags));
-#endif
 	case SYS_RES_IRQ:
 		/*
 		 * Can't alloc legacy interrupt once MSI messages have
diff --git a/sys/dev/pci/pci_host_generic.c b/sys/dev/pci/pci_host_generic.c
--- a/sys/dev/pci/pci_host_generic.c
+++ b/sys/dev/pci/pci_host_generic.c
@@ -363,11 +363,9 @@
 
 	sc = device_get_softc(dev);
 
-#if defined(PCI_RES_BUS)
 	if (type == PCI_RES_BUS) {
 		return (pci_domain_release_bus(sc->ecam, child, rid, res));
 	}
-#endif
 
 	rm = generic_pcie_rman(sc, type, rman_get_flags(res));
 	if (rm != NULL) {
@@ -460,12 +458,10 @@
 
 	sc = device_get_softc(dev);
 
-#if defined(PCI_RES_BUS)
 	if (type == PCI_RES_BUS) {
 		return (pci_domain_alloc_bus(sc->ecam, child, rid, start, end,
 		    count, flags));
 	}
-#endif
 
 	rm = generic_pcie_rman(sc, type, flags);
 	if (rm == NULL)
@@ -504,18 +500,14 @@
 generic_pcie_activate_resource(device_t dev, device_t child, int type,
     int rid, struct resource *r)
 {
-#if defined(PCI_RES_BUS)
 	struct generic_pcie_core_softc *sc;
-#endif
 	rman_res_t start, end;
 	int res;
 
-#if defined(PCI_RES_BUS)
 	sc = device_get_softc(dev);
 	if (type == PCI_RES_BUS) {
 		return (pci_domain_activate_bus(sc->ecam, child, rid, r));
 	}
-#endif
 
 	if ((res = rman_activate_resource(r)) != 0)
 		return (res);
@@ -539,17 +531,13 @@
 generic_pcie_deactivate_resource(device_t dev, device_t child, int type,
     int rid, struct resource *r)
 {
-#if defined(PCI_RES_BUS)
 	struct generic_pcie_core_softc *sc;
-#endif
 	int res;
 
-#if defined(PCI_RES_BUS)
 	sc = device_get_softc(dev);
 	if (type == PCI_RES_BUS) {
 		return (pci_domain_deactivate_bus(sc->ecam, child, rid, r));
 	}
-#endif
 	if ((res = rman_deactivate_resource(r)) != 0)
 		return (res);
 
@@ -575,11 +563,9 @@
 	struct rman *rm;
 
 	sc = device_get_softc(dev);
-#if defined(PCI_RES_BUS)
 	if (type == PCI_RES_BUS)
 		return (pci_domain_adjust_bus(sc->ecam, child, res, start,
 		    end));
-#endif
 
 	rm = generic_pcie_rman(sc, type, rman_get_flags(res));
 	if (rm != NULL)
diff --git a/sys/dev/pci/pci_pci.c b/sys/dev/pci/pci_pci.c
--- a/sys/dev/pci/pci_pci.c
+++ b/sys/dev/pci/pci_pci.c
@@ -166,10 +166,8 @@
 pcib_is_resource_managed(struct pcib_softc *sc, int type, struct resource *r)
 {
 
-#ifdef PCI_RES_BUS
 	if (type == PCI_RES_BUS)
 		return (rman_is_region_manager(r, &sc->bus.rman));
-#endif
 	return (pcib_get_resource_window(sc, type, r) != NULL);
 }
 
@@ -593,7 +591,6 @@
 	pcib_release_window(sc, &sc->io, SYS_RES_IOPORT);
 }
 
-#ifdef PCI_RES_BUS
 /*
  * Allocate a suitable secondary bus for this bridge if needed and
  * initialize the resource manager for the secondary bus range.  Note
@@ -780,7 +777,6 @@
 		    flags));
 	return (NULL);
 }
-#endif
 
 #ifdef PCI_HP
 /*
@@ -1387,10 +1383,6 @@
      * Get current bridge configuration.
      */
     sc->domain = pci_get_domain(dev);
-#if !defined(PCI_RES_BUS)
-    sc->bus.sec = pci_read_config(dev, PCIR_SECBUS_1, 1);
-    sc->bus.sub = pci_read_config(dev, PCIR_SUBBUS_1, 1);
-#endif
     sc->bridgectl = pci_read_config(dev, PCIR_BRIDGECTL_1, 2);
 
     /*
@@ -1418,20 +1410,6 @@
      * Quirk handling.
      */
     switch (pci_get_devid(dev)) {
-#if !defined(PCI_RES_BUS)
-    case 0x12258086:		/* Intel 82454KX/GX (Orion) */
-	{
-	    uint8_t	supbus;
-
-	    supbus = pci_read_config(dev, 0x41, 1);
-	    if (supbus != 0xff) {
-		sc->bus.sec = supbus + 1;
-		sc->bus.sub = supbus + 1;
-	    }
-	    break;
-	}
-#endif
-
     /*
      * The i82380FB mobile docking controller is a PCI-PCI bridge,
      * and it is a subtractive bridge.  However, the ProgIf is wrong
@@ -1444,34 +1422,6 @@
     case 0x060513d7:		/* Toshiba ???? */
 	sc->flags |= PCIB_SUBTRACTIVE;
 	break;
-
-#if !defined(PCI_RES_BUS)
-    /* Compaq R3000 BIOS sets wrong subordinate bus number. */
-    case 0x00dd10de:
-	{
-	    char *cp;
-
-	    if ((cp = kern_getenv("smbios.planar.maker")) == NULL)
-		break;
-	    if (strncmp(cp, "Compal", 6) != 0) {
-		freeenv(cp);
-		break;
-	    }
-	    freeenv(cp);
-	    if ((cp = kern_getenv("smbios.planar.product")) == NULL)
-		break;
-	    if (strncmp(cp, "08A0", 4) != 0) {
-		freeenv(cp);
-		break;
-	    }
-	    freeenv(cp);
-	    if (sc->bus.sub < 0xa) {
-		pci_write_config(dev, PCIR_SUBBUS_1, 0xa, 1);
-		sc->bus.sub = pci_read_config(dev, PCIR_SUBBUS_1, 1);
-	    }
-	    break;
-	}
-#endif
     }
 
     if (pci_msi_device_blacklisted(dev))
@@ -1495,9 +1445,7 @@
 #ifdef PCI_HP
     pcib_probe_hotplug(sc);
 #endif
-#ifdef PCI_RES_BUS
     pcib_setup_secbus(dev, &sc->bus, 1);
-#endif
     pcib_probe_windows(sc);
 #ifdef PCI_HP
     if (sc->flags & PCIB_HOTPLUG)
@@ -1604,9 +1552,7 @@
 	if (error)
 		return (error);
 	pcib_free_windows(sc);
-#ifdef PCI_RES_BUS
 	pcib_free_secbus(dev, &sc->bus);
-#endif
 	return (0);
 }
 
@@ -2088,11 +2034,9 @@
 	}
 
 	switch (type) {
-#ifdef PCI_RES_BUS
 	case PCI_RES_BUS:
 		return (pcib_alloc_subbus(&sc->bus, child, rid, start, end,
 		    count, flags));
-#endif
 	case SYS_RES_IOPORT:
 		if (pcib_is_isa_range(sc, start, end, count))
 			return (NULL);
@@ -2172,7 +2116,6 @@
 		return (bus_generic_adjust_resource(bus, child, type, r,
 		    start, end));
 
-#ifdef PCI_RES_BUS
 	if (type == PCI_RES_BUS) {
 		/*
 		 * If our bus range isn't big enough to grow the sub-allocation
@@ -2186,9 +2129,7 @@
 			if (error != 0)
 				return (error);
 		}
-	} else
-#endif
-	{
+	} else {
 		/*
 		 * Resource is managed and not a secondary bus number, must
 		 * be from one of our windows.
diff --git a/sys/dev/pci/pci_private.h b/sys/dev/pci/pci_private.h
--- a/sys/dev/pci/pci_private.h
+++ b/sys/dev/pci/pci_private.h
@@ -40,9 +40,7 @@
 
 struct pci_softc {
 	bus_dma_tag_t sc_dma_tag;
-#ifdef PCI_RES_BUS
 	struct resource *sc_bus;
-#endif
 };
 
 extern int 	pci_do_power_resume;
diff --git a/sys/dev/pci/pci_subr.c b/sys/dev/pci/pci_subr.c
--- a/sys/dev/pci/pci_subr.c
+++ b/sys/dev/pci/pci_subr.c
@@ -283,7 +283,6 @@
 	return (ERANGE);
 }
 
-#ifdef PCI_RES_BUS
 struct pci_domain {
 	int	pd_domain;
 	struct rman pd_bus_rman;
@@ -410,4 +409,3 @@
 #endif
 	return (rman_deactivate_resource(r));
 }
-#endif /* PCI_RES_BUS */
diff --git a/sys/dev/pci/pcib_private.h b/sys/dev/pci/pcib_private.h
--- a/sys/dev/pci/pcib_private.h
+++ b/sys/dev/pci/pcib_private.h
@@ -84,13 +84,11 @@
 struct pcib_secbus {
 	u_int		sec;
 	u_int		sub;
-#if defined(PCI_RES_BUS)
 	device_t	dev;
 	struct rman	rman;
 	struct resource	*res;
 	const char	*name;
 	int		sub_reg;
-#endif
 };
 
 /*
@@ -140,7 +138,6 @@
 
 int		host_pcib_get_busno(pci_read_config_fn read_config, int bus,
     int slot, int func, uint8_t *busnum);
-#if defined(PCI_RES_BUS)
 struct resource *pci_domain_alloc_bus(int domain, device_t dev, int *rid,
 		    rman_res_t start, rman_res_t end, rman_res_t count, u_int flags);
 int		pci_domain_adjust_bus(int domain, device_t dev,
@@ -157,7 +154,6 @@
 void		pcib_free_secbus(device_t dev, struct pcib_secbus *bus);
 void		pcib_setup_secbus(device_t dev, struct pcib_secbus *bus,
     int min_count);
-#endif
 int		pcib_attach(device_t dev);
 int		pcib_attach_child(device_t dev);
 void		pcib_attach_common(device_t dev);
diff --git a/sys/x86/pci/pci_bus.c b/sys/x86/pci/pci_bus.c
--- a/sys/x86/pci/pci_bus.c
+++ b/sys/x86/pci/pci_bus.c
@@ -595,17 +595,14 @@
     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
 {
 
-#if defined(PCI_RES_BUS)
 	if (type == PCI_RES_BUS)
 		return (pci_domain_alloc_bus(0, child, rid, start, end, count,
 		    flags));
-#endif
 	start = hostb_alloc_start(type, start, end, count);
 	return (bus_generic_alloc_resource(dev, child, type, rid, start, end,
 	    count, flags));
 }
 
-#if defined(PCI_RES_BUS)
 int
 legacy_pcib_adjust_resource(device_t dev, device_t child, int type,
     struct resource *r, rman_res_t start, rman_res_t end)
@@ -643,7 +640,6 @@
 		return (pci_domain_deactivate_bus(0, child, rid, r));
 	return (bus_generic_deactivate_resource(dev, child, type, rid, r));
 }
-#endif
 
 static device_method_t legacy_pcib_methods[] = {
 	/* Device interface */
@@ -658,17 +654,10 @@
 	DEVMETHOD(bus_read_ivar,	legacy_pcib_read_ivar),
 	DEVMETHOD(bus_write_ivar,	legacy_pcib_write_ivar),
 	DEVMETHOD(bus_alloc_resource,	legacy_pcib_alloc_resource),
-#if defined(PCI_RES_BUS)
 	DEVMETHOD(bus_adjust_resource,	legacy_pcib_adjust_resource),
 	DEVMETHOD(bus_release_resource,	legacy_pcib_release_resource),
 	DEVMETHOD(bus_activate_resource, legacy_pcib_activate_resource),
 	DEVMETHOD(bus_deactivate_resource, legacy_pcib_deactivate_resource),
-#else
-	DEVMETHOD(bus_adjust_resource,	bus_generic_adjust_resource),
-	DEVMETHOD(bus_release_resource,	bus_generic_release_resource),
-	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
-	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
-#endif
 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
 
diff --git a/sys/x86/pci/qpi.c b/sys/x86/pci/qpi.c
--- a/sys/x86/pci/qpi.c
+++ b/sys/x86/pci/qpi.c
@@ -246,7 +246,6 @@
 	}
 }
 
-#if defined(PCI_RES_BUS)
 static struct resource *
 qpi_pcib_alloc_resource(device_t dev, device_t child, int type, int *rid,
     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
@@ -258,7 +257,6 @@
 	return (bus_generic_alloc_resource(dev, child, type, rid, start, end,
 	    count, flags));
 }
-#endif
 
 static int
 qpi_pcib_map_msi(device_t pcib, device_t dev, int irq, uint64_t *addr,
@@ -280,18 +278,11 @@
 
 	/* Bus interface */
 	DEVMETHOD(bus_read_ivar,	qpi_pcib_read_ivar),
-#if defined(PCI_RES_BUS)
 	DEVMETHOD(bus_alloc_resource,	qpi_pcib_alloc_resource),
 	DEVMETHOD(bus_adjust_resource,	legacy_pcib_adjust_resource),
 	DEVMETHOD(bus_release_resource,	legacy_pcib_release_resource),
 	DEVMETHOD(bus_activate_resource, legacy_pcib_activate_resource),
 	DEVMETHOD(bus_deactivate_resource, legacy_pcib_deactivate_resource),
-#else
-	DEVMETHOD(bus_alloc_resource,	bus_generic_alloc_resource),
-	DEVMETHOD(bus_release_resource,	bus_generic_release_resource),
-	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
-	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
-#endif
 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
 
diff --git a/sys/x86/x86/mptable_pci.c b/sys/x86/x86/mptable_pci.c
--- a/sys/x86/x86/mptable_pci.c
+++ b/sys/x86/x86/mptable_pci.c
@@ -100,11 +100,9 @@
 {
 	struct mptable_hostb_softc *sc;
 
-#ifdef PCI_RES_BUS
 	if (type == PCI_RES_BUS)
 		return (pci_domain_alloc_bus(0, child, rid, start, end, count,
 		    flags));
-#endif
 	sc = device_get_softc(dev);
 	if (type == SYS_RES_IOPORT && start + count - 1 == end) {
 		if (mptable_is_isa_range(start, end)) {
@@ -141,10 +139,8 @@
 {
 	struct mptable_hostb_softc *sc;
 
-#ifdef PCI_RES_BUS
 	if (type == PCI_RES_BUS)
 		return (pci_domain_adjust_bus(0, child, r, start, end));
-#endif
 	sc = device_get_softc(dev);
 	return (pcib_host_res_adjust(&sc->sc_host_res, child, type, r, start,
 	    end));
@@ -163,15 +159,9 @@
 	DEVMETHOD(bus_write_ivar,	legacy_pcib_write_ivar),
 	DEVMETHOD(bus_alloc_resource,	mptable_hostb_alloc_resource),
 	DEVMETHOD(bus_adjust_resource,	mptable_hostb_adjust_resource),
-#if defined(PCI_RES_BUS)
 	DEVMETHOD(bus_release_resource,	legacy_pcib_release_resource),
 	DEVMETHOD(bus_activate_resource, legacy_pcib_activate_resource),
 	DEVMETHOD(bus_deactivate_resource, legacy_pcib_deactivate_resource),
-#else
-	DEVMETHOD(bus_release_resource,	bus_generic_release_resource),
-	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
-	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
-#endif
 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),