ofwbus.c

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/*-
 * Copyright 1998 Massachusetts Institute of Technology
 * Copyright 2001 by Thomas Moestl <tmm@FreeBSD.org>.
 * Copyright 2006 by Marius Strobl <marius@FreeBSD.org>.
 * All rights reserved.
 *
 * Permission to use, copy, modify, and distribute this software and
 * its documentation for any purpose and without fee is hereby
 * granted, provided that both the above copyright notice and this
 * permission notice appear in all copies, that both the above
 * copyright notice and this permission notice appear in all
 * supporting documentation, and that the name of M.I.T. not be used
 * in advertising or publicity pertaining to distribution of the
 * software without specific, written prior permission.  M.I.T. makes
 * no representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied
 * warranty.
 *
 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      from: FreeBSD: src/sys/i386/i386/nexus.c,v 1.43 2001/02/09
 */
 
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
 
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/pcpu.h>
#include <sys/rman.h>
#ifdef INTRNG
#include <sys/intr.h>
#endif
 
#include <vm/vm.h>
#include <vm/pmap.h>
 
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <dev/ofw/openfirm.h>
#include <dev/fdt/simplebus.h>
 
#include <machine/bus.h>
#include <machine/resource.h>
 
/*
 * The ofwbus (which is a pseudo-bus actually) iterates over the nodes that
 * hang from the Open Firmware root node and adds them as devices to this bus
 * (except some special nodes which are excluded) so that drivers can be
 * attached to them.
 *
 */
 
struct ofwbus_softc {
        struct simplebus_softc simplebus_sc;
        struct rman     sc_intr_rman;
        struct rman     sc_mem_rman;
};
 
#ifndef __aarch64__
static device_identify_t ofwbus_identify;
#endif
static device_probe_t ofwbus_probe;
static device_attach_t ofwbus_attach;
static bus_alloc_resource_t ofwbus_alloc_resource;
static bus_adjust_resource_t ofwbus_adjust_resource;
static bus_release_resource_t ofwbus_release_resource;
 
static device_method_t ofwbus_methods[] = {
        /* Device interface */
#ifndef __aarch64__
        DEVMETHOD(device_identify,      ofwbus_identify),
#endif
        DEVMETHOD(device_probe,         ofwbus_probe),
        DEVMETHOD(device_attach,        ofwbus_attach),
 
        /* Bus interface */
        DEVMETHOD(bus_alloc_resource,   ofwbus_alloc_resource),
        DEVMETHOD(bus_adjust_resource,  ofwbus_adjust_resource),
        DEVMETHOD(bus_release_resource, ofwbus_release_resource),
 
        DEVMETHOD_END
};
 
DEFINE_CLASS_1(ofwbus, ofwbus_driver, ofwbus_methods,
    sizeof(struct ofwbus_softc), simplebus_driver);
static devclass_t ofwbus_devclass;
EARLY_DRIVER_MODULE(ofwbus, nexus, ofwbus_driver, ofwbus_devclass, 0, 0,
    BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
MODULE_VERSION(ofwbus, 1);
 
#ifndef __aarch64__
static void
ofwbus_identify(driver_t *driver, device_t parent)
{
 
        /* Check if Open Firmware has been instantiated */
        if (OF_peer(0) == 0)
                return;
 
        if (device_find_child(parent, "ofwbus", -1) == NULL)
                BUS_ADD_CHILD(parent, 0, "ofwbus", -1);
}
#endif
 
static int
ofwbus_probe(device_t dev)
{
 
#ifdef __aarch64__
        if (OF_peer(0) == 0)
                return (ENXIO);
#endif
 
        device_set_desc(dev, "Open Firmware Device Tree");
        return (BUS_PROBE_NOWILDCARD);
}
 
static int
ofwbus_attach(device_t dev)
{
        struct ofwbus_softc *sc;
        phandle_t node;
        struct ofw_bus_devinfo obd;
 
        sc = device_get_softc(dev);
 
        node = OF_peer(0);
 
        /*
         * If no Open Firmware, bail early
         */
        if (node == -1)
                return (ENXIO);
 
        /*
         * ofwbus bus starts on unamed node in FDT, so we cannot make
         * ofw_bus_devinfo from it. Pass node to simplebus_init directly.
         */
        simplebus_init(dev, node);
        sc->sc_intr_rman.rm_type = RMAN_ARRAY;
        sc->sc_intr_rman.rm_descr = "Interrupts";
        sc->sc_mem_rman.rm_type = RMAN_ARRAY;
        sc->sc_mem_rman.rm_descr = "Device Memory";
        if (rman_init(&sc->sc_intr_rman) != 0 ||
            rman_init(&sc->sc_mem_rman) != 0 ||
            rman_manage_region(&sc->sc_intr_rman, 0, ~0) != 0 ||
            rman_manage_region(&sc->sc_mem_rman, 0, BUS_SPACE_MAXADDR) != 0)
                panic("%s: failed to set up rmans.", __func__);
 
        /*
         * Allow devices to identify.
         */
        bus_generic_probe(dev);
 
        /*
         * Now walk the OFW tree and attach top-level devices.
         */
        for (node = OF_child(node); node > 0; node = OF_peer(node)) {
                if (ofw_bus_gen_setup_devinfo(&obd, node) != 0)
                        continue;
                simplebus_add_device(dev, node, 0, NULL, -1, NULL);
        }
        return (bus_generic_attach(dev));
}
 
static struct resource *
ofwbus_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)
{
        struct ofwbus_softc *sc;
        struct rman *rm;
        struct resource *rv;
        struct resource_list_entry *rle;
        int isdefault, passthrough;
 
        isdefault = RMAN_IS_DEFAULT_RANGE(start, end);
        passthrough = (device_get_parent(child) != bus);
        sc = device_get_softc(bus);
        rle = NULL;
        if (!passthrough && isdefault) {
                rle = resource_list_find(BUS_GET_RESOURCE_LIST(bus, child),
                    type, *rid);
                if (rle == NULL) {
                        if (bootverbose)
                                device_printf(bus, "no default resources for "
                                    "rid = %d, type = %d\n", *rid, type);
                        return (NULL);
                }
                start = rle->start;
                count = ummax(count, rle->count);
                end = ummax(rle->end, start + count - 1);
        }
 
        switch (type) {
        case SYS_RES_IRQ:
                rm = &sc->sc_intr_rman;
                break;
        case SYS_RES_MEMORY:
                rm = &sc->sc_mem_rman;
                break;
        default:
                return (NULL);
        }
 
        rv = rman_reserve_resource(rm, start, end, count, flags & ~RF_ACTIVE,
            child);
        if (rv == NULL)
                return (NULL);
        rman_set_rid(rv, *rid);
 
        if ((flags & RF_ACTIVE) != 0 && bus_activate_resource(child, type,
            *rid, rv) != 0) {
                rman_release_resource(rv);
                return (NULL);
        }
 
        if (!passthrough && rle != NULL) {
                rle->res = rv;
                rle->start = rman_get_start(rv);
                rle->end = rman_get_end(rv);
                rle->count = rle->end - rle->start + 1;
        }
 
        return (rv);
}
 
static int
ofwbus_adjust_resource(device_t bus, device_t child __unused, int type,
    struct resource *r, rman_res_t start, rman_res_t end)
{
        struct ofwbus_softc *sc;
        struct rman *rm;
        device_t ofwbus;
 
        ofwbus = bus;
        while (strcmp(device_get_name(device_get_parent(ofwbus)), "root") != 0)
                ofwbus = device_get_parent(ofwbus);
        sc = device_get_softc(ofwbus);
        switch (type) {
        case SYS_RES_IRQ:
                rm = &sc->sc_intr_rman;
                break;
        case SYS_RES_MEMORY:
                rm = &sc->sc_mem_rman;
                break;
        default:
                return (EINVAL);
        }
        if (rm == NULL)
                return (ENXIO);
        if (rman_is_region_manager(r, rm) == 0)
                return (EINVAL);
        return (rman_adjust_resource(r, start, end));
}
 
static int
ofwbus_release_resource(device_t bus, device_t child, int type,
    int rid, struct resource *r)
{
        struct resource_list_entry *rle;
        int passthrough;
        int error;
 
        passthrough = (device_get_parent(child) != bus);
        if (!passthrough) {
                /* Clean resource list entry */
                rle = resource_list_find(BUS_GET_RESOURCE_LIST(bus, child),
                    type, rid);
                if (rle != NULL)
                        rle->res = NULL;
        }
 
        if ((rman_get_flags(r) & RF_ACTIVE) != 0) {
                error = bus_deactivate_resource(child, type, rid, r);
                if (error)
                        return (error);
        }
        return (rman_release_resource(r));
}