/*
* (C) Copyright David Gibson <[email protected]>, IBM Corporation. 2005.
*
*
* This program 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 program 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 program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*/

#include "dtc.h"
#include "srcpos.h"

#define FTF_FULLPATH 0x1
#define FTF_VARALIGN 0x2
#define FTF_NAMEPROPS 0x4
#define FTF_BOOTCPUID 0x8
#define FTF_STRTABSIZE 0x10
#define FTF_STRUCTSIZE 0x20
#define FTF_NOPS 0x40

static struct version_info {
int version;
int last_comp_version;
int hdr_size;
int flags;
} version_table[] = {
{1, 1, FDT_V1_SIZE,
FTF_FULLPATH|FTF_VARALIGN|FTF_NAMEPROPS},
{2, 1, FDT_V2_SIZE,
FTF_FULLPATH|FTF_VARALIGN|FTF_NAMEPROPS|FTF_BOOTCPUID},
{3, 1, FDT_V3_SIZE,
FTF_FULLPATH|FTF_VARALIGN|FTF_NAMEPROPS|FTF_BOOTCPUID|FTF_STRTABSIZE},
{16, 16, FDT_V3_SIZE,
FTF_BOOTCPUID|FTF_STRTABSIZE|FTF_NOPS},
{17, 16, FDT_V17_SIZE,
FTF_BOOTCPUID|FTF_STRTABSIZE|FTF_STRUCTSIZE|FTF_NOPS},
};

struct emitter {
void (*cell)(void *, cell_t);
void (*string)(void *, char *, int);
void (*align)(void *, int);
void (*data)(void *, struct data);
void (*beginnode)(void *, struct label *labels);
void (*endnode)(void *, struct label *labels);
void (*property)(void *, struct label *labels);
};

static void bin_emit_cell(void *e, cell_t val)
{
struct data *dtbuf = e;

*dtbuf = data_append_cell(*dtbuf, val);
}

static void bin_emit_string(void *e, char *str, int len)
{
struct data *dtbuf = e;

if (len == 0)
len = strlen(str);

*dtbuf = data_append_data(*dtbuf, str, len);
*dtbuf = data_append_byte(*dtbuf, '\0');
}

static void bin_emit_align(void *e, int a)
{
struct data *dtbuf = e;

*dtbuf = data_append_align(*dtbuf, a);
}

static void bin_emit_data(void *e, struct data d)
{
struct data *dtbuf = e;

*dtbuf = data_append_data(*dtbuf, d.val, d.len);
}

static void bin_emit_beginnode(void *e, struct label *labels)
{
bin_emit_cell(e, FDT_BEGIN_NODE);
}

static void bin_emit_endnode(void *e, struct label *labels)
{
bin_emit_cell(e, FDT_END_NODE);
}

static void bin_emit_property(void *e, struct label *labels)
{
bin_emit_cell(e, FDT_PROP);
}

static struct emitter bin_emitter = {
.cell = bin_emit_cell,
.string = bin_emit_string,
.align = bin_emit_align,
.data = bin_emit_data,
.beginnode = bin_emit_beginnode,
.endnode = bin_emit_endnode,
.property = bin_emit_property,
};

static void emit_label(FILE *f, const char *prefix, const char *label)
{
fprintf(f, "\t.globl\t%s_%s\n", prefix, label);
fprintf(f, "%s_%s:\n", prefix, label);
fprintf(f, "_%s_%s:\n", prefix, label);
}

static void emit_offset_label(FILE *f, const char *label, int offset)
{
fprintf(f, "\t.globl\t%s\n", label);
fprintf(f, "%s\t= . + %d\n", label, offset);
}

#define ASM_EMIT_BELONG(f, fmt, ...) \
{ \
fprintf((f), "\t.byte\t((" fmt ") >> 24) & 0xff\n", __VA_ARGS__); \
fprintf((f), "\t.byte\t((" fmt ") >> 16) & 0xff\n", __VA_ARGS__); \
fprintf((f), "\t.byte\t((" fmt ") >> 8) & 0xff\n", __VA_ARGS__); \
fprintf((f), "\t.byte\t(" fmt ") & 0xff\n", __VA_ARGS__); \
}

static void asm_emit_cell(void *e, cell_t val)
{
FILE *f = e;

fprintf(f, "\t.byte 0x%02x; .byte 0x%02x; .byte 0x%02x; .byte 0x%02x\n",
(val >> 24) & 0xff, (val >> 16) & 0xff,
(val >> 8) & 0xff, val & 0xff);
}

static void asm_emit_string(void *e, char *str, int len)
{
FILE *f = e;
char c = 0;

if (len != 0) {
/* XXX: ewww */
c = str[len];
str[len] = '\0';
}

fprintf(f, "\t.string\t\"%s\"\n", str);

if (len != 0) {
str[len] = c;
}
}

static void asm_emit_align(void *e, int a)
{
FILE *f = e;

fprintf(f, "\t.balign\t%d, 0\n", a);
}

static void asm_emit_data(void *e, struct data d)
{
FILE *f = e;
int off = 0;
struct marker *m = d.markers;

for_each_marker_of_type(m, LABEL)
emit_offset_label(f, m->ref, m->offset);

while ((d.len - off) >= sizeof(uint32_t)) {
asm_emit_cell(e, fdt32_to_cpu(*((uint32_t *)(d.val+off))));
off += sizeof(uint32_t);
}

while ((d.len - off) >= 1) {
fprintf(f, "\t.byte\t0x%hhx\n", d.val[off]);
off += 1;
}

assert(off == d.len);
}

static void asm_emit_beginnode(void *e, struct label *labels)
{
FILE *f = e;
struct label *l;

for_each_label(labels, l) {
fprintf(f, "\t.globl\t%s\n", l->label);
fprintf(f, "%s:\n", l->label);
}
fprintf(f, "\t/* FDT_BEGIN_NODE */\n");
asm_emit_cell(e, FDT_BEGIN_NODE);
}

static void asm_emit_endnode(void *e, struct label *labels)
{
FILE *f = e;
struct label *l;

fprintf(f, "\t/* FDT_END_NODE */\n");
asm_emit_cell(e, FDT_END_NODE);
for_each_label(labels, l) {
fprintf(f, "\t.globl\t%s_end\n", l->label);
fprintf(f, "%s_end:\n", l->label);
}
}

static void asm_emit_property(void *e, struct label *labels)
{
FILE *f = e;
struct label *l;

for_each_label(labels, l) {
fprintf(f, "\t.globl\t%s\n", l->label);
fprintf(f, "%s:\n", l->label);
}
fprintf(f, "\t/* FDT_PROP */\n");
asm_emit_cell(e, FDT_PROP);
}

static struct emitter asm_emitter = {
.cell = asm_emit_cell,
.string = asm_emit_string,
.align = asm_emit_align,
.data = asm_emit_data,
.beginnode = asm_emit_beginnode,
.endnode = asm_emit_endnode,
.property = asm_emit_property,
};

static int stringtable_insert(struct data *d, const char *str)
{
int i;

/* FIXME: do this more efficiently? */

for (i = 0; i < d->len; i++) {
if (streq(str, d->val + i))
return i;
}

*d = data_append_data(*d, str, strlen(str)+1);
return i;
}

static void flatten_tree(struct node *tree, struct emitter *emit,
void *etarget, struct data *strbuf,
struct version_info *vi)
{
struct property *prop;
struct node *child;
int seen_name_prop = 0;

if (tree->deleted)
return;

emit->beginnode(etarget, tree->labels);

if (vi->flags & FTF_FULLPATH)
emit->string(etarget, tree->fullpath, 0);
else
emit->string(etarget, tree->name, 0);

emit->align(etarget, sizeof(cell_t));

for_each_property(tree, prop) {
int nameoff;

if (streq(prop->name, "name"))
seen_name_prop = 1;

nameoff = stringtable_insert(strbuf, prop->name);

emit->property(etarget, prop->labels);
emit->cell(etarget, prop->val.len);
emit->cell(etarget, nameoff);

if ((vi->flags & FTF_VARALIGN) && (prop->val.len >= 8))
emit->align(etarget, 8);

emit->data(etarget, prop->val);
emit->align(etarget, sizeof(cell_t));
}

if ((vi->flags & FTF_NAMEPROPS) && !seen_name_prop) {
emit->property(etarget, NULL);
emit->cell(etarget, tree->basenamelen+1);
emit->cell(etarget, stringtable_insert(strbuf, "name"));

if ((vi->flags & FTF_VARALIGN) && ((tree->basenamelen+1) >= 8))
emit->align(etarget, 8);

emit->string(etarget, tree->name, tree->basenamelen);
emit->align(etarget, sizeof(cell_t));
}

for_each_child(tree, child) {
flatten_tree(child, emit, etarget, strbuf, vi);
}

emit->endnode(etarget, tree->labels);
}

static struct data flatten_reserve_list(struct reserve_info *reservelist,
struct version_info *vi)
{
struct reserve_info *re;
struct data d = empty_data;
static struct fdt_reserve_entry null_re = {0,0};
int j;

for (re = reservelist; re; re = re->next) {
d = data_append_re(d, &re->re);
}
/*
* Add additional reserved slots if the user asked for them.
*/
for (j = 0; j < reservenum; j++) {
d = data_append_re(d, &null_re);
}

return d;
}

static void make_fdt_header(struct fdt_header *fdt,
struct version_info *vi,
int reservesize, int dtsize, int strsize,
int boot_cpuid_phys)
{
int reserve_off;

reservesize += sizeof(struct fdt_reserve_entry);

memset(fdt, 0xff, sizeof(*fdt));

fdt->magic = cpu_to_fdt32(FDT_MAGIC);
fdt->version = cpu_to_fdt32(vi->version);
fdt->last_comp_version = cpu_to_fdt32(vi->last_comp_version);

/* Reserve map should be doubleword aligned */
reserve_off = ALIGN(vi->hdr_size, 8);

fdt->off_mem_rsvmap = cpu_to_fdt32(reserve_off);
fdt->off_dt_struct = cpu_to_fdt32(reserve_off + reservesize);
fdt->off_dt_strings = cpu_to_fdt32(reserve_off + reservesize
+ dtsize);
fdt->totalsize = cpu_to_fdt32(reserve_off + reservesize + dtsize + strsize);

if (vi->flags & FTF_BOOTCPUID)
fdt->boot_cpuid_phys = cpu_to_fdt32(boot_cpuid_phys);
if (vi->flags & FTF_STRTABSIZE)
fdt->size_dt_strings = cpu_to_fdt32(strsize);
if (vi->flags & FTF_STRUCTSIZE)
fdt->size_dt_struct = cpu_to_fdt32(dtsize);
}

void dt_to_blob(FILE *f, struct boot_info *bi, int version)
{
struct version_info *vi = NULL;
int i;
struct data blob = empty_data;
struct data reservebuf = empty_data;
struct data dtbuf = empty_data;
struct data strbuf = empty_data;
struct fdt_header fdt;
int padlen = 0;

for (i = 0; i < ARRAY_SIZE(version_table); i++) {
if (version_table[i].version == version)
vi = &version_table[i];
}
if (!vi)
die("Unknown device tree blob version %d\n", version);

flatten_tree(bi->dt, &bin_emitter, &dtbuf, &strbuf, vi);
bin_emit_cell(&dtbuf, FDT_END);

reservebuf = flatten_reserve_list(bi->reservelist, vi);

/* Make header */
make_fdt_header(&fdt, vi, reservebuf.len, dtbuf.len, strbuf.len,
bi->boot_cpuid_phys);

/*
* If the user asked for more space than is used, adjust the totalsize.
*/
if (minsize > 0) {
padlen = minsize - fdt32_to_cpu(fdt.totalsize);
if ((padlen < 0) && (quiet < 1))
fprintf(stderr,
"Warning: blob size %d >= minimum size %d\n",
fdt32_to_cpu(fdt.totalsize), minsize);
}

if (padsize > 0)
padlen = padsize;

if (padlen > 0) {
int tsize = fdt32_to_cpu(fdt.totalsize);
tsize += padlen;
fdt.totalsize = cpu_to_fdt32(tsize);
}

/*
* Assemble the blob: start with the header, add with alignment
* the reserve buffer, add the reserve map terminating zeroes,
* the device tree itself, and finally the strings.
*/
blob = data_append_data(blob, &fdt, vi->hdr_size);
blob = data_append_align(blob, 8);
blob = data_merge(blob, reservebuf);
blob = data_append_zeroes(blob, sizeof(struct fdt_reserve_entry));
blob = data_merge(blob, dtbuf);
blob = data_merge(blob, strbuf);

/*
* If the user asked for more space than is used, pad out the blob.
*/
if (padlen > 0)
blob = data_append_zeroes(blob, padlen);

if (fwrite(blob.val, blob.len, 1, f) != 1) {
if (ferror(f))
die("Error writing device tree blob: %s\n",
strerror(errno));
else
die("Short write on device tree blob\n");
}

/*
* data_merge() frees the right-hand element so only the blob
* remains to be freed.
*/
data_free(blob);
}

static void dump_stringtable_asm(FILE *f, struct data strbuf)
{
const char *p;
int len;

p = strbuf.val;

while (p < (strbuf.val + strbuf.len)) {
len = strlen(p);
fprintf(f, "\t.string \"%s\"\n", p);
p += len+1;
}
}

void dt_to_asm(FILE *f, struct boot_info *bi, int version)
{
struct version_info *vi = NULL;
int i;
struct data strbuf = empty_data;
struct reserve_info *re;
const char *symprefix = "dt";

for (i = 0; i < ARRAY_SIZE(version_table); i++) {
if (version_table[i].version == version)
vi = &version_table[i];
}
if (!vi)
die("Unknown device tree blob version %d\n", version);

fprintf(f, "/* autogenerated by dtc, do not edit */\n\n");

emit_label(f, symprefix, "blob_start");
emit_label(f, symprefix, "header");
fprintf(f, "\t/* magic */\n");
asm_emit_cell(f, FDT_MAGIC);
fprintf(f, "\t/* totalsize */\n");
ASM_EMIT_BELONG(f, "_%s_blob_abs_end - _%s_blob_start",
symprefix, symprefix);
fprintf(f, "\t/* off_dt_struct */\n");
ASM_EMIT_BELONG(f, "_%s_struct_start - _%s_blob_start",
symprefix, symprefix);
fprintf(f, "\t/* off_dt_strings */\n");
ASM_EMIT_BELONG(f, "_%s_strings_start - _%s_blob_start",
symprefix, symprefix);
fprintf(f, "\t/* off_mem_rsvmap */\n");
ASM_EMIT_BELONG(f, "_%s_reserve_map - _%s_blob_start",
symprefix, symprefix);
fprintf(f, "\t/* version */\n");
asm_emit_cell(f, vi->version);
fprintf(f, "\t/* last_comp_version */\n");
asm_emit_cell(f, vi->last_comp_version);

if (vi->flags & FTF_BOOTCPUID) {
fprintf(f, "\t/* boot_cpuid_phys */\n");
asm_emit_cell(f, bi->boot_cpuid_phys);
}

if (vi->flags & FTF_STRTABSIZE) {
fprintf(f, "\t/* size_dt_strings */\n");
ASM_EMIT_BELONG(f, "_%s_strings_end - _%s_strings_start",
symprefix, symprefix);
}

if (vi->flags & FTF_STRUCTSIZE) {
fprintf(f, "\t/* size_dt_struct */\n");
ASM_EMIT_BELONG(f, "_%s_struct_end - _%s_struct_start",
symprefix, symprefix);
}

/*
* Reserve map entries.
* Align the reserve map to a doubleword boundary.
* Each entry is an (address, size) pair of u64 values.
* Always supply a zero-sized temination entry.
*/
asm_emit_align(f, 8);
emit_label(f, symprefix, "reserve_map");

fprintf(f, "/* Memory reserve map from source file */\n");

/*
* Use .long on high and low halfs of u64s to avoid .quad
* as it appears .quad isn't available in some assemblers.
*/
for (re = bi->reservelist; re; re = re->next) {
struct label *l;

for_each_label(re->labels, l) {
fprintf(f, "\t.globl\t%s\n", l->label);
fprintf(f, "%s:\n", l->label);
}
ASM_EMIT_BELONG(f, "0x%08x", (unsigned int)(re->re.address >> 32));
ASM_EMIT_BELONG(f, "0x%08x",
(unsigned int)(re->re.address & 0xffffffff));
ASM_EMIT_BELONG(f, "0x%08x", (unsigned int)(re->re.size >> 32));
ASM_EMIT_BELONG(f, "0x%08x", (unsigned int)(re->re.size & 0xffffffff));
}
for (i = 0; i < reservenum; i++) {
fprintf(f, "\t.long\t0, 0\n\t.long\t0, 0\n");
}

fprintf(f, "\t.long\t0, 0\n\t.long\t0, 0\n");

emit_label(f, symprefix, "struct_start");
flatten_tree(bi->dt, &asm_emitter, f, &strbuf, vi);

fprintf(f, "\t/* FDT_END */\n");
asm_emit_cell(f, FDT_END);
emit_label(f, symprefix, "struct_end");

emit_label(f, symprefix, "strings_start");
dump_stringtable_asm(f, strbuf);
emit_label(f, symprefix, "strings_end");

emit_label(f, symprefix, "blob_end");

/*
* If the user asked for more space than is used, pad it out.
*/
if (minsize > 0) {
fprintf(f, "\t.space\t%d - (_%s_blob_end - _%s_blob_start), 0\n",
minsize, symprefix, symprefix);
}
if (padsize > 0) {
fprintf(f, "\t.space\t%d, 0\n", padsize);
}
emit_label(f, symprefix, "blob_abs_end");

data_free(strbuf);
}

struct inbuf {
char *base, *limit, *ptr;
};

static void inbuf_init(struct inbuf *inb, void *base, void *limit)
{
inb->base = base;
inb->limit = limit;
inb->ptr = inb->base;
}

static void flat_read_chunk(struct inbuf *inb, void *p, int len)
{
if ((inb->ptr + len) > inb->limit)
die("Premature end of data parsing flat device tree\n");

memcpy(p, inb->ptr, len);

inb->ptr += len;
}

static uint32_t flat_read_word(struct inbuf *inb)
{
uint32_t val;

assert(((inb->ptr - inb->base) % sizeof(val)) == 0);

flat_read_chunk(inb, &val, sizeof(val));

return fdt32_to_cpu(val);
}

static void flat_realign(struct inbuf *inb, int align)
{
int off = inb->ptr - inb->base;

inb->ptr = inb->base + ALIGN(off, align);
if (inb->ptr > inb->limit)
die("Premature end of data parsing flat device tree\n");
}

static char *flat_read_string(struct inbuf *inb)
{
int len = 0;
const char *p = inb->ptr;
char *str;

do {
if (p >= inb->limit)
die("Premature end of data parsing flat device tree\n");
len++;
} while ((*p++) != '\0');

str = xstrdup(inb->ptr);

inb->ptr += len;

flat_realign(inb, sizeof(uint32_t));

return str;
}

static struct data flat_read_data(struct inbuf *inb, int len)
{
struct data d = empty_data;

if (len == 0)
return empty_data;

d = data_grow_for(d, len);
d.len = len;

flat_read_chunk(inb, d.val, len);

flat_realign(inb, sizeof(uint32_t));

return d;
}

static char *flat_read_stringtable(struct inbuf *inb, int offset)
{
const char *p;

p = inb->base + offset;
while (1) {
if (p >= inb->limit || p < inb->base)
die("String offset %d overruns string table\n",
offset);

if (*p == '\0')
break;

p++;
}

return xstrdup(inb->base + offset);
}

static struct property *flat_read_property(struct inbuf *dtbuf,
struct inbuf *strbuf, int flags)
{
uint32_t proplen, stroff;
char *name;
struct data val;

proplen = flat_read_word(dtbuf);
stroff = flat_read_word(dtbuf);

name = flat_read_stringtable(strbuf, stroff);

if ((flags & FTF_VARALIGN) && (proplen >= 8))
flat_realign(dtbuf, 8);

val = flat_read_data(dtbuf, proplen);

return build_property(name, val);
}


static struct reserve_info *flat_read_mem_reserve(struct inbuf *inb)
{
struct reserve_info *reservelist = NULL;
struct reserve_info *new;
struct fdt_reserve_entry re;

/*
* Each entry is a pair of u64 (addr, size) values for 4 cell_t's.
* List terminates at an entry with size equal to zero.
*
* First pass, count entries.
*/
while (1) {
flat_read_chunk(inb, &re, sizeof(re));
re.address = fdt64_to_cpu(re.address);
re.size = fdt64_to_cpu(re.size);
if (re.size == 0)
break;

new = build_reserve_entry(re.address, re.size);
reservelist = add_reserve_entry(reservelist, new);
}

return reservelist;
}


static char *nodename_from_path(const char *ppath, const char *cpath)
{
int plen;

plen = strlen(ppath);

if (!strneq(ppath, cpath, plen))
die("Path \"%s\" is not valid as a child of \"%s\"\n",
cpath, ppath);

/* root node is a special case */
if (!streq(ppath, "/"))
plen++;

return xstrdup(cpath + plen);
}

static struct node *unflatten_tree(struct inbuf *dtbuf,
struct inbuf *strbuf,
const char *parent_flatname, int flags)
{
struct node *node;
char *flatname;
uint32_t val;

node = build_node(NULL, NULL);

flatname = flat_read_string(dtbuf);

if (flags & FTF_FULLPATH)
node->name = nodename_from_path(parent_flatname, flatname);
else
node->name = flatname;

do {
struct property *prop;
struct node *child;

val = flat_read_word(dtbuf);
switch (val) {
case FDT_PROP:
if (node->children)
fprintf(stderr, "Warning: Flat tree input has "
"subnodes preceding a property.\n");
prop = flat_read_property(dtbuf, strbuf, flags);
add_property(node, prop);
break;

case FDT_BEGIN_NODE:
child = unflatten_tree(dtbuf,strbuf, flatname, flags);
add_child(node, child);
break;

case FDT_END_NODE:
break;

case FDT_END:
die("Premature FDT_END in device tree blob\n");
break;

case FDT_NOP:
if (!(flags & FTF_NOPS))
fprintf(stderr, "Warning: NOP tag found in flat tree"
" version <16\n");

/* Ignore */
break;

default:
die("Invalid opcode word %08x in device tree blob\n",
val);
}
} while (val != FDT_END_NODE);

return node;
}


struct boot_info *dt_from_blob(const char *fname)
{
FILE *f;
uint32_t magic, totalsize, version, size_dt, boot_cpuid_phys;
uint32_t off_dt, off_str, off_mem_rsvmap;
int rc;
char *blob;
struct fdt_header *fdt;
char *p;
struct inbuf dtbuf, strbuf;
struct inbuf memresvbuf;
int sizeleft;
struct reserve_info *reservelist;
struct node *tree;
uint32_t val;
int flags = 0;

f = srcfile_relative_open(fname, NULL);

rc = fread(&magic, sizeof(magic), 1, f);
if (ferror(f))
die("Error reading DT blob magic number: %s\n",
strerror(errno));
if (rc < 1) {
if (feof(f))
die("EOF reading DT blob magic number\n");
else
die("Mysterious short read reading magic number\n");
}

magic = fdt32_to_cpu(magic);
if (magic != FDT_MAGIC)
die("Blob has incorrect magic number\n");

rc = fread(&totalsize, sizeof(totalsize), 1, f);
if (ferror(f))
die("Error reading DT blob size: %s\n", strerror(errno));
if (rc < 1) {
if (feof(f))
die("EOF reading DT blob size\n");
else
die("Mysterious short read reading blob size\n");
}

totalsize = fdt32_to_cpu(totalsize);
if (totalsize < FDT_V1_SIZE)
die("DT blob size (%d) is too small\n", totalsize);

blob = xmalloc(totalsize);

fdt = (struct fdt_header *)blob;
fdt->magic = cpu_to_fdt32(magic);
fdt->totalsize = cpu_to_fdt32(totalsize);

sizeleft = totalsize - sizeof(magic) - sizeof(totalsize);
p = blob + sizeof(magic) + sizeof(totalsize);

while (sizeleft) {
if (feof(f))
die("EOF before reading %d bytes of DT blob\n",
totalsize);

rc = fread(p, 1, sizeleft, f);
if (ferror(f))
die("Error reading DT blob: %s\n",
strerror(errno));

sizeleft -= rc;
p += rc;
}

off_dt = fdt32_to_cpu(fdt->off_dt_struct);
off_str = fdt32_to_cpu(fdt->off_dt_strings);
off_mem_rsvmap = fdt32_to_cpu(fdt->off_mem_rsvmap);
version = fdt32_to_cpu(fdt->version);
boot_cpuid_phys = fdt32_to_cpu(fdt->boot_cpuid_phys);

if (off_mem_rsvmap >= totalsize)
die("Mem Reserve structure offset exceeds total size\n");

if (off_dt >= totalsize)
die("DT structure offset exceeds total size\n");

if (off_str > totalsize)
die("String table offset exceeds total size\n");

if (version >= 3) {
uint32_t size_str = fdt32_to_cpu(fdt->size_dt_strings);
if (off_str+size_str > totalsize)
die("String table extends past total size\n");
inbuf_init(&strbuf, blob + off_str, blob + off_str + size_str);
} else {
inbuf_init(&strbuf, blob + off_str, blob + totalsize);
}

if (version >= 17) {
size_dt = fdt32_to_cpu(fdt->size_dt_struct);
if (off_dt+size_dt > totalsize)
die("Structure block extends past total size\n");
}

if (version < 16) {
flags |= FTF_FULLPATH | FTF_NAMEPROPS | FTF_VARALIGN;
} else {
flags |= FTF_NOPS;
}

inbuf_init(&memresvbuf,
blob + off_mem_rsvmap, blob + totalsize);
inbuf_init(&dtbuf, blob + off_dt, blob + totalsize);

reservelist = flat_read_mem_reserve(&memresvbuf);

val = flat_read_word(&dtbuf);

if (val != FDT_BEGIN_NODE)
die("Device tree blob doesn't begin with FDT_BEGIN_NODE (begins with 0x%08x)\n", val);

tree = unflatten_tree(&dtbuf, &strbuf, "", flags);

val = flat_read_word(&dtbuf);
if (val != FDT_END)
die("Device tree blob doesn't end with FDT_END\n");

free(blob);

fclose(f);

return build_boot_info(reservelist, tree, boot_cpuid_phys);
}