ofw_bus_subr.c

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/*-
 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 *
 * Copyright (c) 2001 - 2003 by Thomas Moestl <tmm@FreeBSD.org>.
 * Copyright (c) 2005 Marius Strobl <marius@FreeBSD.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification, immediately at the beginning of the file.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 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.
 */
 
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
 
#include "opt_platform.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/errno.h>
#include <sys/libkern.h>
#include <sys/sbuf.h>
 
#include <machine/resource.h>
 
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <dev/ofw/openfirm.h>
 
#include "ofw_bus_if.h"
 
#define OFW_COMPAT_LEN  255
#define OFW_STATUS_LEN  16
 
int
ofw_bus_gen_setup_devinfo(struct ofw_bus_devinfo *obd, phandle_t node)
{
 
        if (obd == NULL)
                return (ENOMEM);
        /* The 'name' property is considered mandatory. */
        if ((OF_getprop_alloc(node, "name", (void **)&obd->obd_name)) == -1)
                return (EINVAL);
        OF_getprop_alloc(node, "compatible", (void **)&obd->obd_compat);
        OF_getprop_alloc(node, "device_type", (void **)&obd->obd_type);
        OF_getprop_alloc(node, "model", (void **)&obd->obd_model);
        OF_getprop_alloc(node, "status", (void **)&obd->obd_status);
        obd->obd_node = node;
        return (0);
}
 
void
ofw_bus_gen_destroy_devinfo(struct ofw_bus_devinfo *obd)
{
 
        if (obd == NULL)
                return;
        if (obd->obd_compat != NULL)
                free(obd->obd_compat, M_OFWPROP);
        if (obd->obd_model != NULL)
                free(obd->obd_model, M_OFWPROP);
        if (obd->obd_name != NULL)
                free(obd->obd_name, M_OFWPROP);
        if (obd->obd_type != NULL)
                free(obd->obd_type, M_OFWPROP);
        if (obd->obd_status != NULL)
                free(obd->obd_status, M_OFWPROP);
}
 
int
ofw_bus_gen_child_pnpinfo(device_t cbdev, device_t child, struct sbuf *sb)
{
 
        if (!ofw_bus_status_okay(child))
                return (0);
 
        if (ofw_bus_get_name(child) != NULL) {
                sbuf_printf(sb, "name=%s ", ofw_bus_get_name(child));
        }
 
        if (ofw_bus_get_compat(child) != NULL) {
                sbuf_printf(sb, "compat=%s ", ofw_bus_get_compat(child));
        }
 
        return (0);
};
 
const char *
ofw_bus_gen_get_compat(device_t bus, device_t dev)
{
        const struct ofw_bus_devinfo *obd;
 
        obd = OFW_BUS_GET_DEVINFO(bus, dev);
        if (obd == NULL)
                return (NULL);
        return (obd->obd_compat);
}
 
const char *
ofw_bus_gen_get_model(device_t bus, device_t dev)
{
        const struct ofw_bus_devinfo *obd;
 
        obd = OFW_BUS_GET_DEVINFO(bus, dev);
        if (obd == NULL)
                return (NULL);
        return (obd->obd_model);
}
 
const char *
ofw_bus_gen_get_name(device_t bus, device_t dev)
{
        const struct ofw_bus_devinfo *obd;
 
        obd = OFW_BUS_GET_DEVINFO(bus, dev);
        if (obd == NULL)
                return (NULL);
        return (obd->obd_name);
}
 
phandle_t
ofw_bus_gen_get_node(device_t bus, device_t dev)
{
        const struct ofw_bus_devinfo *obd;
 
        obd = OFW_BUS_GET_DEVINFO(bus, dev);
        if (obd == NULL)
                return ((phandle_t)-1);
        return (obd->obd_node);
}
 
const char *
ofw_bus_gen_get_type(device_t bus, device_t dev)
{
        const struct ofw_bus_devinfo *obd;
 
        obd = OFW_BUS_GET_DEVINFO(bus, dev);
        if (obd == NULL)
                return (NULL);
        return (obd->obd_type);
}
 
const char *
ofw_bus_get_status(device_t dev)
{
        const struct ofw_bus_devinfo *obd;
 
        obd = OFW_BUS_GET_DEVINFO(device_get_parent(dev), dev);
        if (obd == NULL)
                return (NULL);
 
        return (obd->obd_status);
}
 
int
ofw_bus_status_okay(device_t dev)
{
        const char *status;
 
        status = ofw_bus_get_status(dev);
        if (status == NULL || strcmp(status, "okay") == 0 ||
            strcmp(status, "ok") == 0)
                return (1);
 
        return (0);
}
 
int
ofw_bus_node_status_okay(phandle_t node)
{
        char status[OFW_STATUS_LEN];
        int len;
 
        len = OF_getproplen(node, "status");
        if (len <= 0)
                return (1);
 
        OF_getprop(node, "status", status, OFW_STATUS_LEN);
        if ((len == 5 && (bcmp(status, "okay", len) == 0)) ||
            (len == 3 && (bcmp(status, "ok", len))))
                return (1);
 
        return (0);
}
 
static int
ofw_bus_node_is_compatible_int(const char *compat, int len,
    const char *onecompat)
{
        int onelen, l, ret;
 
        onelen = strlen(onecompat);
 
        ret = 0;
        while (len > 0) {
                if (strlen(compat) == onelen &&
                    strncasecmp(compat, onecompat, onelen) == 0) {
                        /* Found it. */
                        ret = 1;
                        break;
                }
 
                /* Slide to the next sub-string. */
                l = strlen(compat) + 1;
                compat += l;
                len -= l;
        }
 
        return (ret);
}
 
int
ofw_bus_node_is_compatible(phandle_t node, const char *compatstr)
{
        char compat[OFW_COMPAT_LEN];
        int len, rv;
 
        if ((len = OF_getproplen(node, "compatible")) <= 0)
                return (0);
 
        bzero(compat, OFW_COMPAT_LEN);
 
        if (OF_getprop(node, "compatible", compat, OFW_COMPAT_LEN) < 0)
                return (0);
 
        rv = ofw_bus_node_is_compatible_int(compat, len, compatstr);
 
        return (rv);
}
 
int
ofw_bus_is_compatible(device_t dev, const char *onecompat)
{
        phandle_t node;
        const char *compat;
        int len;
 
        if ((compat = ofw_bus_get_compat(dev)) == NULL)
                return (0);
 
        if ((node = ofw_bus_get_node(dev)) == -1)
                return (0);
 
        /* Get total 'compatible' prop len */
        if ((len = OF_getproplen(node, "compatible")) <= 0)
                return (0);
 
        return (ofw_bus_node_is_compatible_int(compat, len, onecompat));
}
 
int
ofw_bus_is_compatible_strict(device_t dev, const char *compatible)
{
        const char *compat;
        size_t len;
 
        if ((compat = ofw_bus_get_compat(dev)) == NULL)
                return (0);
 
        len = strlen(compatible);
        if (strlen(compat) == len &&
            strncasecmp(compat, compatible, len) == 0)
                return (1);
 
        return (0);
}
 
const struct ofw_compat_data *
ofw_bus_search_compatible(device_t dev, const struct ofw_compat_data *compat)
{
 
        if (compat == NULL)
                return NULL;
 
        for (; compat->ocd_str != NULL; ++compat) {
                if (ofw_bus_is_compatible(dev, compat->ocd_str))
                        break;
        }
 
        return (compat);
}
 
int
ofw_bus_has_prop(device_t dev, const char *propname)
{
        phandle_t node;
 
        if ((node = ofw_bus_get_node(dev)) == -1)
                return (0);
 
        return (OF_hasprop(node, propname));
}
 
void
ofw_bus_setup_iinfo(phandle_t node, struct ofw_bus_iinfo *ii, int intrsz)
{
        pcell_t addrc;
        int msksz;
 
        if (OF_getencprop(node, "#address-cells", &addrc, sizeof(addrc)) == -1)
                addrc = 2;
        ii->opi_addrc = addrc * sizeof(pcell_t);
 
        ii->opi_imapsz = OF_getencprop_alloc(node, "interrupt-map",
            (void **)&ii->opi_imap);
        if (ii->opi_imapsz > 0) {
                msksz = OF_getencprop_alloc(node, "interrupt-map-mask",
                    (void **)&ii->opi_imapmsk);
                /*
                 * Failure to get the mask is ignored; a full mask is used
                 * then.  We barf on bad mask sizes, however.
                 */
                if (msksz != -1 && msksz != ii->opi_addrc + intrsz)
                        panic("ofw_bus_setup_iinfo: bad interrupt-map-mask "
                            "property!");
        }
}
 
int
ofw_bus_lookup_imap(phandle_t node, struct ofw_bus_iinfo *ii, void *reg,
    int regsz, void *pintr, int pintrsz, void *mintr, int mintrsz,
    phandle_t *iparent)
{
        uint8_t maskbuf[regsz + pintrsz];
        int rv;
 
        if (ii->opi_imapsz <= 0)
                return (0);
        KASSERT(regsz >= ii->opi_addrc,
            ("ofw_bus_lookup_imap: register size too small: %d < %d",
                regsz, ii->opi_addrc));
        if (node != -1) {
                rv = OF_getencprop(node, "reg", reg, regsz);
                if (rv < regsz)
                        panic("ofw_bus_lookup_imap: cannot get reg property");
        }
        return (ofw_bus_search_intrmap(pintr, pintrsz, reg, ii->opi_addrc,
            ii->opi_imap, ii->opi_imapsz, ii->opi_imapmsk, maskbuf, mintr,
            mintrsz, iparent));
}
 
/*
 * Map an interrupt using the firmware reg, interrupt-map and
 * interrupt-map-mask properties.
 * The interrupt property to be mapped must be of size intrsz, and pointed to
 * by intr.  The regs property of the node for which the mapping is done must
 * be passed as regs. This property is an array of register specifications;
 * the size of the address part of such a specification must be passed as
 * physsz.  Only the first element of the property is used.
 * imap and imapsz hold the interrupt mask and it's size.
 * imapmsk is a pointer to the interrupt-map-mask property, which must have
 * a size of physsz + intrsz; it may be NULL, in which case a full mask is
 * assumed.
 * maskbuf must point to a buffer of length physsz + intrsz.
 * The interrupt is returned in result, which must point to a buffer of length
 * rintrsz (which gives the expected size of the mapped interrupt).
 * Returns number of cells in the interrupt if a mapping was found, 0 otherwise.
 */
int
ofw_bus_search_intrmap(void *intr, int intrsz, void *regs, int physsz,
    void *imap, int imapsz, void *imapmsk, void *maskbuf, void *result,
    int rintrsz, phandle_t *iparent)
{
        phandle_t parent;
        uint8_t *ref = maskbuf;
        uint8_t *uiintr = intr;
        uint8_t *uiregs = regs;
        uint8_t *uiimapmsk = imapmsk;
        uint8_t *mptr;
        pcell_t paddrsz;
        pcell_t pintrsz;
        int i, tsz;
 
        if (imapmsk != NULL) {
                for (i = 0; i < physsz; i++)
                        ref[i] = uiregs[i] & uiimapmsk[i];
                for (i = 0; i < intrsz; i++)
                        ref[physsz + i] = uiintr[i] & uiimapmsk[physsz + i];
        } else {
                bcopy(regs, ref, physsz);
                bcopy(intr, ref + physsz, intrsz);
        }
 
        mptr = imap;
        i = imapsz;
        paddrsz = 0;
        while (i > 0) {
                bcopy(mptr + physsz + intrsz, &parent, sizeof(parent));
#ifndef OFW_IMAP_NO_IPARENT_ADDR_CELLS
                /*
                 * Find if we need to read the parent address data.
                 * CHRP-derived OF bindings, including ePAPR-compliant FDTs,
                 * use this as an optional part of the specifier.
                 */
                if (OF_getencprop(OF_node_from_xref(parent),
                    "#address-cells", &paddrsz, sizeof(paddrsz)) == -1)
                        paddrsz = 0;    /* default */
                paddrsz *= sizeof(pcell_t);
#endif
 
                if (OF_searchencprop(OF_node_from_xref(parent),
                    "#interrupt-cells", &pintrsz, sizeof(pintrsz)) == -1)
                        pintrsz = 1;    /* default */
                pintrsz *= sizeof(pcell_t);
 
                /* Compute the map stride size. */
                tsz = physsz + intrsz + sizeof(phandle_t) + paddrsz + pintrsz;
                KASSERT(i >= tsz, ("ofw_bus_search_intrmap: truncated map"));
 
                if (bcmp(ref, mptr, physsz + intrsz) == 0) {
                        bcopy(mptr + physsz + intrsz + sizeof(parent) + paddrsz,
                            result, MIN(rintrsz, pintrsz));
 
                        if (iparent != NULL)
                                *iparent = parent;
                        return (pintrsz/sizeof(pcell_t));
                }
                mptr += tsz;
                i -= tsz;
        }
        return (0);
}
 
int
ofw_bus_msimap(phandle_t node, uint16_t pci_rid, phandle_t *msi_parent,
    uint32_t *msi_rid)
{
        pcell_t *map, mask, msi_base, rid_base, rid_length;
        ssize_t len;
        uint32_t masked_rid;
        int err, i;
 
        /* TODO: This should be OF_searchprop_alloc if we had it */
        len = OF_getencprop_alloc_multi(node, "msi-map", sizeof(*map),
            (void **)&map);
        if (len < 0) {
                if (msi_parent != NULL) {
                        *msi_parent = 0;
                        OF_getencprop(node, "msi-parent", msi_parent,
                            sizeof(*msi_parent));
                }
                if (msi_rid != NULL)
                        *msi_rid = pci_rid;
                return (0);
        }
 
        err = ENOENT;
        mask = 0xffffffff;
        OF_getencprop(node, "msi-map-mask", &mask, sizeof(mask));
 
        masked_rid = pci_rid & mask;
        for (i = 0; i < len; i += 4) {
                rid_base = map[i + 0];
                rid_length = map[i + 3];
 
                if (masked_rid < rid_base ||
                    masked_rid >= (rid_base + rid_length))
                        continue;
 
                msi_base = map[i + 2];
 
                if (msi_parent != NULL)
                        *msi_parent = map[i + 1];
                if (msi_rid != NULL)
                        *msi_rid = masked_rid - rid_base + msi_base;
                err = 0;
                break;
        }
 
        free(map, M_OFWPROP);
 
        return (err);
}
 
static int
ofw_bus_reg_to_rl_helper(device_t dev, phandle_t node, pcell_t acells, pcell_t scells,
    struct resource_list *rl, const char *reg_source)
{
        uint64_t phys, size;
        ssize_t i, j, rid, nreg, ret;
        uint32_t *reg;
        char *name;
 
        /*
         * This may be just redundant when having ofw_bus_devinfo
         * but makes this routine independent of it.
         */
        ret = OF_getprop_alloc(node, "name", (void **)&name);
        if (ret == -1)
                name = NULL;
 
        ret = OF_getencprop_alloc_multi(node, reg_source, sizeof(*reg),
            (void **)&reg);
        nreg = (ret == -1) ? 0 : ret;
 
        if (nreg % (acells + scells) != 0) {
                if (bootverbose)
                        device_printf(dev, "Malformed reg property on <%s>\n",
                            (name == NULL) ? "unknown" : name);
                nreg = 0;
        }
 
        for (i = 0, rid = 0; i < nreg; i += acells + scells, rid++) {
                phys = size = 0;
                for (j = 0; j < acells; j++) {
                        phys <<= 32;
                        phys |= reg[i + j];
                }
                for (j = 0; j < scells; j++) {
                        size <<= 32;
                        size |= reg[i + acells + j];
                }
                /* Skip the dummy reg property of glue devices like ssm(4). */
                if (size != 0)
                        resource_list_add(rl, SYS_RES_MEMORY, rid,
                            phys, phys + size - 1, size);
        }
        free(name, M_OFWPROP);
        free(reg, M_OFWPROP);
 
        return (0);
}
 
int
ofw_bus_reg_to_rl(device_t dev, phandle_t node, pcell_t acells, pcell_t scells,
    struct resource_list *rl)
{
 
        return (ofw_bus_reg_to_rl_helper(dev, node, acells, scells, rl, "reg"));
}
 
int
ofw_bus_assigned_addresses_to_rl(device_t dev, phandle_t node, pcell_t acells,
    pcell_t scells, struct resource_list *rl)
{
 
        return (ofw_bus_reg_to_rl_helper(dev, node, acells, scells,
            rl, "assigned-addresses"));
}
 
/*
 * Get interrupt parent for given node.
 * Returns 0 if interrupt parent doesn't exist.
 */
phandle_t
ofw_bus_find_iparent(phandle_t node)
{
        phandle_t iparent;
 
        if (OF_searchencprop(node, "interrupt-parent", &iparent,
                    sizeof(iparent)) == -1) {
                for (iparent = node; iparent != 0;
                    iparent = OF_parent(iparent)) {
                        if (OF_hasprop(iparent, "interrupt-controller"))
                                break;
                }
                iparent = OF_xref_from_node(iparent);
        }
        return (iparent);
}
 
int
ofw_bus_intr_to_rl(device_t dev, phandle_t node,
    struct resource_list *rl, int *rlen)
{
        phandle_t iparent;
        uint32_t icells, *intr;
        int err, i, irqnum, nintr, rid;
        boolean_t extended;
 
        nintr = OF_getencprop_alloc_multi(node, "interrupts",  sizeof(*intr),
            (void **)&intr);
        if (nintr > 0) {
                iparent = ofw_bus_find_iparent(node);
                if (iparent == 0) {
                        device_printf(dev, "No interrupt-parent found, "
                            "assuming direct parent\n");
                        iparent = OF_parent(node);
                        iparent = OF_xref_from_node(iparent);
                }
                if (OF_searchencprop(OF_node_from_xref(iparent), 
                    "#interrupt-cells", &icells, sizeof(icells)) == -1) {
                        device_printf(dev, "Missing #interrupt-cells "
                            "property, assuming <1>\n");
                        icells = 1;
                }
                if (icells < 1 || icells > nintr) {
                        device_printf(dev, "Invalid #interrupt-cells property "
                            "value <%d>, assuming <1>\n", icells);
                        icells = 1;
                }
                extended = false;
        } else {
                nintr = OF_getencprop_alloc_multi(node, "interrupts-extended",
                    sizeof(*intr), (void **)&intr);
                if (nintr <= 0)
                        return (0);
                extended = true;
        }
        err = 0;
        rid = 0;
        for (i = 0; i < nintr; i += icells) {
                if (extended) {
                        iparent = intr[i++];
                        if (OF_searchencprop(OF_node_from_xref(iparent), 
                            "#interrupt-cells", &icells, sizeof(icells)) == -1) {
                                device_printf(dev, "Missing #interrupt-cells "
                                    "property\n");
                                err = ENOENT;
                                break;
                        }
                        if (icells < 1 || (i + icells) > nintr) {
                                device_printf(dev, "Invalid #interrupt-cells "
                                    "property value <%d>\n", icells);
                                err = ERANGE;
                                break;
                        }
                }
                irqnum = ofw_bus_map_intr(dev, iparent, icells, &intr[i]);
                resource_list_add(rl, SYS_RES_IRQ, rid++, irqnum, irqnum, 1);
        }
        if (rlen != NULL)
                *rlen = rid;
        free(intr, M_OFWPROP);
        return (err);
}
 
int
ofw_bus_intr_by_rid(device_t dev, phandle_t node, int wanted_rid,
    phandle_t *producer, int *ncells, pcell_t **cells)
{
        phandle_t iparent;
        uint32_t icells, *intr;
        int err, i, nintr, rid;
        boolean_t extended;
 
        nintr = OF_getencprop_alloc_multi(node, "interrupts",  sizeof(*intr),
            (void **)&intr);
        if (nintr > 0) {
                iparent = ofw_bus_find_iparent(node);
                if (iparent == 0) {
                        device_printf(dev, "No interrupt-parent found, "
                            "assuming direct parent\n");
                        iparent = OF_parent(node);
                        iparent = OF_xref_from_node(iparent);
                }
                if (OF_searchencprop(OF_node_from_xref(iparent),
                    "#interrupt-cells", &icells, sizeof(icells)) == -1) {
                        device_printf(dev, "Missing #interrupt-cells "
                            "property, assuming <1>\n");
                        icells = 1;
                }
                if (icells < 1 || icells > nintr) {
                        device_printf(dev, "Invalid #interrupt-cells property "
                            "value <%d>, assuming <1>\n", icells);
                        icells = 1;
                }
                extended = false;
        } else {
                nintr = OF_getencprop_alloc_multi(node, "interrupts-extended",
                    sizeof(*intr), (void **)&intr);
                if (nintr <= 0)
                        return (ESRCH);
                extended = true;
        }
        err = ESRCH;
        rid = 0;
        for (i = 0; i < nintr; i += icells, rid++) {
                if (extended) {
                        iparent = intr[i++];
                        if (OF_searchencprop(OF_node_from_xref(iparent),
                            "#interrupt-cells", &icells, sizeof(icells)) == -1) {
                                device_printf(dev, "Missing #interrupt-cells "
                                    "property\n");
                                err = ENOENT;
                                break;
                        }
                        if (icells < 1 || (i + icells) > nintr) {
                                device_printf(dev, "Invalid #interrupt-cells "
                                    "property value <%d>\n", icells);
                                err = ERANGE;
                                break;
                        }
                }
                if (rid == wanted_rid) {
                        *cells = malloc(icells * sizeof(**cells), M_OFWPROP,
                            M_WAITOK);
                        *producer = iparent;
                        *ncells= icells;
                        memcpy(*cells, intr + i, icells * sizeof(**cells));
                        err = 0;
                        break;
                }
        }
        free(intr, M_OFWPROP);
        return (err);
}
 
phandle_t
ofw_bus_find_child(phandle_t start, const char *child_name)
{
        char *name;
        int ret;
        phandle_t child;
 
        for (child = OF_child(start); child != 0; child = OF_peer(child)) {
                ret = OF_getprop_alloc(child, "name", (void **)&name);
                if (ret == -1)
                        continue;
                if (strcmp(name, child_name) == 0) {
                        free(name, M_OFWPROP);
                        return (child);
                }
 
                free(name, M_OFWPROP);
        }
 
        return (0);
}
 
phandle_t
ofw_bus_find_compatible(phandle_t node, const char *onecompat)
{
        phandle_t child, ret;
 
        /*
         * Traverse all children of 'start' node, and find first with
         * matching 'compatible' property.
         */
        for (child = OF_child(node); child != 0; child = OF_peer(child)) {
                if (ofw_bus_node_is_compatible(child, onecompat) != 0)
                        return (child);
 
                ret = ofw_bus_find_compatible(child, onecompat);
                if (ret != 0)
                        return (ret);
        }
        return (0);
}
 
device_t
ofw_bus_find_child_device_by_phandle(device_t bus, phandle_t node)
{
        device_t *children, retval, child;
        int nkid, i;
 
        /*
         * Nothing can match the flag value for no node.
         */
        if (node == -1)
                return (NULL);
 
        /*
         * Search the children for a match. We microoptimize
         * a bit by not using ofw_bus_get since we already know
         * the parent. We do not recurse.
         */
        if (device_get_children(bus, &children, &nkid) != 0)
                return (NULL);
        retval = NULL;
        for (i = 0; i < nkid; i++) {
                child = children[i];
                if (OFW_BUS_GET_NODE(bus, child) == node) {
                        retval = child;
                        break;
                }
        }
        free(children, M_TEMP);
 
        return (retval);
}
 
/*
 * Parse property that contain list of xrefs and values
 * (like standard "clocks" and "resets" properties)
 * Input arguments:
 *  node - consumers device node
 *  list_name  - name of parsed list - "clocks"
 *  cells_name - name of size property - "#clock-cells"
 *  idx - the index of the requested list entry, or, if -1, an indication
 *        to return the number of entries in the parsed list.
 * Output arguments:
 *  producer - handle of producer
 *  ncells   - number of cells in result or the number of items in the list when
 *             idx == -1.
 *  cells    - array of decoded cells
 */
static int
ofw_bus_parse_xref_list_internal(phandle_t node, const char *list_name,
    const char *cells_name, int idx, phandle_t *producer, int *ncells,
    pcell_t **cells)
{
        phandle_t pnode;
        phandle_t *elems;
        uint32_t  pcells;
        int rv, i, j, nelems, cnt;
 
        elems = NULL;
        nelems = OF_getencprop_alloc_multi(node, list_name,  sizeof(*elems),
            (void **)&elems);
        if (nelems <= 0)
                return (ENOENT);
        rv = (idx == -1) ? 0 : ENOENT;
        for (i = 0, cnt = 0; i < nelems; i += pcells, cnt++) {
                pnode = elems[i++];
                if (OF_getencprop(OF_node_from_xref(pnode),
                    cells_name, &pcells, sizeof(pcells)) == -1) {
                        printf("Missing %s property\n", cells_name);
                        rv = ENOENT;
                        break;
                }
 
                if ((i + pcells) > nelems) {
                        printf("Invalid %s property value <%d>\n", cells_name,
                            pcells);
                        rv = ERANGE;
                        break;
                }
                if (cnt == idx) {
                        *cells= malloc(pcells * sizeof(**cells), M_OFWPROP,
                            M_WAITOK);
                        *producer = pnode;
                        *ncells = pcells;
                        for (j = 0; j < pcells; j++)
                                (*cells)[j] = elems[i + j];
                        rv = 0;
                        break;
                }
        }
        if (elems != NULL)
                free(elems, M_OFWPROP);
        if (idx == -1 && rv == 0)
                *ncells = cnt;
        return (rv);
}
 
/*
 * Parse property that contain list of xrefs and values
 * (like standard "clocks" and "resets" properties)
 * Input arguments:
 *  node - consumers device node
 *  list_name  - name of parsed list - "clocks"
 *  cells_name - name of size property - "#clock-cells"
 *  idx - the index of the requested list entry (>= 0)
 * Output arguments:
 *  producer - handle of producer
 *  ncells   - number of cells in result
 *  cells    - array of decoded cells
 */
int
ofw_bus_parse_xref_list_alloc(phandle_t node, const char *list_name,
    const char *cells_name, int idx, phandle_t *producer, int *ncells,
    pcell_t **cells)
{
 
        KASSERT(idx >= 0,
            ("ofw_bus_parse_xref_list_alloc: negative index supplied"));
 
        return (ofw_bus_parse_xref_list_internal(node, list_name, cells_name,
                    idx, producer, ncells, cells));
}
 
/*
 * Parse property that contain list of xrefs and values
 * (like standard "clocks" and "resets" properties)
 * and determine the number of items in the list
 * Input arguments:
 *  node - consumers device node
 *  list_name  - name of parsed list - "clocks"
 *  cells_name - name of size property - "#clock-cells"
 * Output arguments:
 *  count - number of items in list
 */
int
ofw_bus_parse_xref_list_get_length(phandle_t node, const char *list_name,
    const char *cells_name, int *count)
{
 
        return (ofw_bus_parse_xref_list_internal(node, list_name, cells_name,
                    -1, NULL, count, NULL));
}
 
/*
 * Find index of string in string list property (case sensitive).
 */
int
ofw_bus_find_string_index(phandle_t node, const char *list_name,
    const char *name, int *idx)
{
        char *elems;
        int rv, i, cnt, nelems;
 
        elems = NULL;
        nelems = OF_getprop_alloc(node, list_name, (void **)&elems);
        if (nelems <= 0)
                return (ENOENT);
 
        rv = ENOENT;
        for (i = 0, cnt = 0; i < nelems; cnt++) {
                if (strcmp(elems + i, name) == 0) {
                        *idx = cnt;
                        rv = 0;
                        break;
                }
                i += strlen(elems + i) + 1;
        }
 
        if (elems != NULL)
                free(elems, M_OFWPROP);
        return (rv);
}
 
/*
 * Create zero terminated array of strings from string list property.
 */
int
ofw_bus_string_list_to_array(phandle_t node, const char *list_name,
   const char ***out_array)
{
        char *elems, *tptr;
        const char **array;
        int i, cnt, nelems, len;
 
        elems = NULL;
        nelems = OF_getprop_alloc(node, list_name, (void **)&elems);
        if (nelems <= 0)
                return (nelems);
 
        /* Count number of strings. */
        for (i = 0, cnt = 0; i < nelems; cnt++)
                i += strlen(elems + i) + 1;
 
        /* Allocate space for arrays and all strings. */
        array = malloc((cnt + 1) * sizeof(char *) + nelems, M_OFWPROP,
            M_WAITOK);
 
        /* Get address of first string. */
        tptr = (char *)(array + cnt + 1);
 
        /* Copy strings. */
        memcpy(tptr, elems, nelems);
        free(elems, M_OFWPROP);
 
        /* Fill string pointers. */
        for (i = 0, cnt = 0; i < nelems; cnt++) {
                len = strlen(tptr) + 1;
                array[cnt] = tptr;
                i += len;
                tptr += len;
        }
        array[cnt] = NULL;
        *out_array = array;
 
        return (cnt);
}