Committer: Michael Beasley <mike@snafu.setup>

[mikesnafu-overlay.git] / arch / powerpc / boot / libfdt / fdt_rw.c

/*
 * libfdt - Flat Device Tree manipulation
 * Copyright (C) 2006 David Gibson, IBM Corporation.
 *
 * libfdt is dual licensed: you can use it either under the terms of
 * the GPL, or the BSD license, at your option.
 *
 *  a) This library is free software; you can redistribute it and/or
 *     modify it under the terms of the GNU General Public License as
 *     published by the Free Software Foundation; either version 2 of the
 *     License, or (at your option) any later version.
 *
 *     This library is distributed in the hope that it will be useful,
 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *     GNU General Public License for more details.
 *
 *     You should have received a copy of the GNU General Public
 *     License along with this library; if not, write to the Free
 *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
 *     MA 02110-1301 USA
 *
 * Alternatively,
 *
 *  b) 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.
 *     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 COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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 "libfdt_env.h"

#include <fdt.h>
#include <libfdt.h>

#include "libfdt_internal.h"

static int _blocks_misordered(const void *fdt,
                              int mem_rsv_size, int struct_size)
{
        return (fdt_off_mem_rsvmap(fdt) < ALIGN(sizeof(struct fdt_header), 8))
                || (fdt_off_dt_struct(fdt) <
                    (fdt_off_mem_rsvmap(fdt) + mem_rsv_size))
                || (fdt_off_dt_strings(fdt) <
                    (fdt_off_dt_struct(fdt) + struct_size))
                || (fdt_totalsize(fdt) <
                    (fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt)));
}

static int rw_check_header(void *fdt)
{
        int err;

        if ((err = fdt_check_header(fdt)))
                return err;
        if (fdt_version(fdt) < 17)
                return -FDT_ERR_BADVERSION;
        if (_blocks_misordered(fdt, sizeof(struct fdt_reserve_entry),
                               fdt_size_dt_struct(fdt)))
                return -FDT_ERR_BADLAYOUT;
        if (fdt_version(fdt) > 17)
                fdt_set_version(fdt, 17);

        return 0;
}

#define RW_CHECK_HEADER(fdt) \
        { \
                int err; \
                if ((err = rw_check_header(fdt)) != 0) \
                        return err; \
        }

static inline int _blob_data_size(void *fdt)
{
        return fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt);
}

static int _blob_splice(void *fdt, void *p, int oldlen, int newlen)
{
        void *end = fdt + _blob_data_size(fdt);

        if (((p + oldlen) < p) || ((p + oldlen) > end))
                return -FDT_ERR_BADOFFSET;
        if ((end - oldlen + newlen) > (fdt + fdt_totalsize(fdt)))
                return -FDT_ERR_NOSPACE;
        memmove(p + newlen, p + oldlen, end - p - oldlen);
        return 0;
}

static int _blob_splice_mem_rsv(void *fdt, struct fdt_reserve_entry *p,
                                int oldn, int newn)
{
        int delta = (newn - oldn) * sizeof(*p);
        int err;
        err = _blob_splice(fdt, p, oldn * sizeof(*p), newn * sizeof(*p));
        if (err)
                return err;
        fdt_set_off_dt_struct(fdt, fdt_off_dt_struct(fdt) + delta);
        fdt_set_off_dt_strings(fdt, fdt_off_dt_strings(fdt) + delta);
        return 0;
}

static int _blob_splice_struct(void *fdt, void *p,
                               int oldlen, int newlen)
{
        int delta = newlen - oldlen;
        int err;

        if ((err = _blob_splice(fdt, p, oldlen, newlen)))
                return err;

        fdt_set_size_dt_struct(fdt, fdt_size_dt_struct(fdt) + delta);
        fdt_set_off_dt_strings(fdt, fdt_off_dt_strings(fdt) + delta);
        return 0;
}

static int _blob_splice_string(void *fdt, int newlen)
{
        void *p = fdt + fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt);
        int err;

        if ((err = _blob_splice(fdt, p, 0, newlen)))
                return err;

        fdt_set_size_dt_strings(fdt, fdt_size_dt_strings(fdt) + newlen);
        return 0;
}

static int _find_add_string(void *fdt, const char *s)
{
        char *strtab = (char *)fdt + fdt_off_dt_strings(fdt);
        const char *p;
        char *new;
        int len = strlen(s) + 1;
        int err;

        p = _fdt_find_string(strtab, fdt_size_dt_strings(fdt), s);
        if (p)
                /* found it */
                return (p - strtab);

        new = strtab + fdt_size_dt_strings(fdt);
        err = _blob_splice_string(fdt, len);
        if (err)
                return err;

        memcpy(new, s, len);
        return (new - strtab);
}

int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size)
{
        struct fdt_reserve_entry *re;
        int err;

        if ((err = rw_check_header(fdt)))
                return err;

        re = _fdt_mem_rsv_w(fdt, fdt_num_mem_rsv(fdt));
        err = _blob_splice_mem_rsv(fdt, re, 0, 1);
        if (err)
                return err;

        re->address = cpu_to_fdt64(address);
        re->size = cpu_to_fdt64(size);
        return 0;
}

int fdt_del_mem_rsv(void *fdt, int n)
{
        struct fdt_reserve_entry *re = _fdt_mem_rsv_w(fdt, n);
        int err;

        if ((err = rw_check_header(fdt)))
                return err;
        if (n >= fdt_num_mem_rsv(fdt))
                return -FDT_ERR_NOTFOUND;

        err = _blob_splice_mem_rsv(fdt, re, 1, 0);
        if (err)
                return err;
        return 0;
}

static int _resize_property(void *fdt, int nodeoffset, const char *name, int len,
                            struct fdt_property **prop)
{
        int oldlen;
        int err;

        *prop = fdt_get_property_w(fdt, nodeoffset, name, &oldlen);
        if (! (*prop))
                return oldlen;

        if ((err = _blob_splice_struct(fdt, (*prop)->data,
                                       ALIGN(oldlen, FDT_TAGSIZE),
                                       ALIGN(len, FDT_TAGSIZE))))
                return err;

        (*prop)->len = cpu_to_fdt32(len);
        return 0;
}

static int _add_property(void *fdt, int nodeoffset, const char *name, int len,
                         struct fdt_property **prop)
{
        uint32_t tag;
        int proplen;
        int nextoffset;
        int namestroff;
        int err;

        tag = fdt_next_tag(fdt, nodeoffset, &nextoffset);
        if (tag != FDT_BEGIN_NODE)
                return -FDT_ERR_BADOFFSET;

        namestroff = _find_add_string(fdt, name);
        if (namestroff < 0)
                return namestroff;

        *prop = _fdt_offset_ptr_w(fdt, nextoffset);
        proplen = sizeof(**prop) + ALIGN(len, FDT_TAGSIZE);

        err = _blob_splice_struct(fdt, *prop, 0, proplen);
        if (err)
                return err;

        (*prop)->tag = cpu_to_fdt32(FDT_PROP);
        (*prop)->nameoff = cpu_to_fdt32(namestroff);
        (*prop)->len = cpu_to_fdt32(len);
        return 0;
}

int fdt_setprop(void *fdt, int nodeoffset, const char *name,
                const void *val, int len)
{
        struct fdt_property *prop;
        int err;

        if ((err = rw_check_header(fdt)))
                return err;

        err = _resize_property(fdt, nodeoffset, name, len, &prop);
        if (err == -FDT_ERR_NOTFOUND)
                err = _add_property(fdt, nodeoffset, name, len, &prop);
        if (err)
                return err;

        memcpy(prop->data, val, len);
        return 0;
}

int fdt_delprop(void *fdt, int nodeoffset, const char *name)
{
        struct fdt_property *prop;
        int len, proplen;

        RW_CHECK_HEADER(fdt);

        prop = fdt_get_property_w(fdt, nodeoffset, name, &len);
        if (! prop)
                return len;

        proplen = sizeof(*prop) + ALIGN(len, FDT_TAGSIZE);
        return _blob_splice_struct(fdt, prop, proplen, 0);
}

int fdt_add_subnode_namelen(void *fdt, int parentoffset,
                            const char *name, int namelen)
{
        struct fdt_node_header *nh;
        int offset, nextoffset;
        int nodelen;
        int err;
        uint32_t tag;
        uint32_t *endtag;

        RW_CHECK_HEADER(fdt);

        offset = fdt_subnode_offset_namelen(fdt, parentoffset, name, namelen);
        if (offset >= 0)
                return -FDT_ERR_EXISTS;
        else if (offset != -FDT_ERR_NOTFOUND)
                return offset;

        /* Try to place the new node after the parent's properties */
        fdt_next_tag(fdt, parentoffset, &nextoffset); /* skip the BEGIN_NODE */
        do {
                offset = nextoffset;
                tag = fdt_next_tag(fdt, offset, &nextoffset);
        } while (tag == FDT_PROP);

        nh = _fdt_offset_ptr_w(fdt, offset);
        nodelen = sizeof(*nh) + ALIGN(namelen+1, FDT_TAGSIZE) + FDT_TAGSIZE;

        err = _blob_splice_struct(fdt, nh, 0, nodelen);
        if (err)
                return err;

        nh->tag = cpu_to_fdt32(FDT_BEGIN_NODE);
        memset(nh->name, 0, ALIGN(namelen+1, FDT_TAGSIZE));
        memcpy(nh->name, name, namelen);
        endtag = (uint32_t *)((void *)nh + nodelen - FDT_TAGSIZE);
        *endtag = cpu_to_fdt32(FDT_END_NODE);

        return offset;
}

int fdt_add_subnode(void *fdt, int parentoffset, const char *name)
{
        return fdt_add_subnode_namelen(fdt, parentoffset, name, strlen(name));
}

int fdt_del_node(void *fdt, int nodeoffset)
{
        int endoffset;

        RW_CHECK_HEADER(fdt);

        endoffset = _fdt_node_end_offset(fdt, nodeoffset);
        if (endoffset < 0)
                return endoffset;

        return _blob_splice_struct(fdt, _fdt_offset_ptr_w(fdt, nodeoffset),
                                   endoffset - nodeoffset, 0);
}

static void _packblocks(const void *fdt, void *buf,
                       int mem_rsv_size, int struct_size)
{
        int mem_rsv_off, struct_off, strings_off;

        mem_rsv_off = ALIGN(sizeof(struct fdt_header), 8);
        struct_off = mem_rsv_off + mem_rsv_size;
        strings_off = struct_off + struct_size;

        memmove(buf + mem_rsv_off, fdt + fdt_off_mem_rsvmap(fdt), mem_rsv_size);
        fdt_set_off_mem_rsvmap(buf, mem_rsv_off);

        memmove(buf + struct_off, fdt + fdt_off_dt_struct(fdt), struct_size);
        fdt_set_off_dt_struct(buf, struct_off);
        fdt_set_size_dt_struct(buf, struct_size);

        memmove(buf + strings_off, fdt + fdt_off_dt_strings(fdt),
                fdt_size_dt_strings(fdt));
        fdt_set_off_dt_strings(buf, strings_off);
        fdt_set_size_dt_strings(buf, fdt_size_dt_strings(fdt));
}

int fdt_open_into(const void *fdt, void *buf, int bufsize)
{
        int err;
        int mem_rsv_size, struct_size;
        int newsize;
        void *tmp;

        err = fdt_check_header(fdt);
        if (err)
                return err;

        mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)
                * sizeof(struct fdt_reserve_entry);

        if (fdt_version(fdt) >= 17) {
                struct_size = fdt_size_dt_struct(fdt);
        } else {
                struct_size = 0;
                while (fdt_next_tag(fdt, struct_size, &struct_size) != FDT_END)
                        ;
        }

        if (!_blocks_misordered(fdt, mem_rsv_size, struct_size)) {
                /* no further work necessary */
                err = fdt_move(fdt, buf, bufsize);
                if (err)
                        return err;
                fdt_set_version(buf, 17);
                fdt_set_size_dt_struct(buf, struct_size);
                fdt_set_totalsize(buf, bufsize);
                return 0;
        }

        /* Need to reorder */
        newsize = ALIGN(sizeof(struct fdt_header), 8) + mem_rsv_size
                + struct_size + fdt_size_dt_strings(fdt);

        if (bufsize < newsize)
                return -FDT_ERR_NOSPACE;

        if (((buf + newsize) <= fdt)
            || (buf >= (fdt + fdt_totalsize(fdt)))) {
                tmp = buf;
        } else {
                tmp = (void *)fdt + fdt_totalsize(fdt);
                if ((tmp + newsize) > (buf + bufsize))
                        return -FDT_ERR_NOSPACE;
        }

        _packblocks(fdt, tmp, mem_rsv_size, struct_size);
        memmove(buf, tmp, newsize);

        fdt_set_magic(buf, FDT_MAGIC);
        fdt_set_totalsize(buf, bufsize);
        fdt_set_version(buf, 17);
        fdt_set_last_comp_version(buf, 16);
        fdt_set_boot_cpuid_phys(buf, fdt_boot_cpuid_phys(fdt));

        return 0;
}

int fdt_pack(void *fdt)
{
        int mem_rsv_size;
        int err;

        err = rw_check_header(fdt);
        if (err)
                return err;

        mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)
                * sizeof(struct fdt_reserve_entry);
        _packblocks(fdt, fdt, mem_rsv_size, fdt_size_dt_struct(fdt));
        fdt_set_totalsize(fdt, _blob_data_size(fdt));

        return 0;
}