/*
* Functions for working with the Flattened Device Tree data format
*
* Copyright 2009 Benjamin Herrenschmidt, IBM Corp
* benh@kernel.crashing.org
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/initrd.h>
#include <linux/memblock.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
#ifdef CONFIG_PPC
#include <asm/machdep.h>
#endif /* CONFIG_PPC */
#include <asm/page.h>
char *of_fdt_get_string(struct boot_param_header *blob, u32 offset)
{
return ((char *)blob) +
be32_to_cpu(blob->off_dt_strings) + offset;
}
/**
* of_fdt_get_property - Given a node in the given flat blob, return
* the property ptr
*/
void *of_fdt_get_property(struct boot_param_header *blob,
unsigned long node, const char *name,
unsigned long *size)
{
unsigned long p = node;
do {
u32 tag = be32_to_cpup((__be32 *)p);
u32 sz, noff;
const char *nstr;
p += 4;
if (tag == OF_DT_NOP)
continue;
if (tag != OF_DT_PROP)
return NULL;
sz = be32_to_cpup((__be32 *)p);
noff = be32_to_cpup((__be32 *)(p + 4));
p += 8;
if (be32_to_cpu(blob->version) < 0x10)
p = ALIGN(p, sz >= 8 ? 8 : 4);
nstr = of_fdt_get_string(blob, noff);
if (nstr == NULL) {
pr_warning("Can't find property index name !\n");
return NULL;
}
if (strcmp(name, nstr) == 0) {
if (size)
*size = sz;
return (void *)p;
}
p += sz;
p = ALIGN(p, 4);
} while (1);
}
/**
* of_fdt_is_compatible - Return true if given node from the given blob has
* compat in its compatible list
* @blob: A device tree blob
* @node: node to test
* @compat: compatible string to compare with compatible list.
*
* On match, returns a non-zero value with smaller values returned for more
* specific compatible values.
*/
int of_fdt_is_compatible(struct boot_param_header *blob,
unsigned long node, const char *compat)
{
const char *cp;
unsigned long cplen, l, score = 0;
cp = of_fdt_get_property(blob, node, "compatible", &cplen);
if (cp == NULL)
return 0;
while (cplen > 0) {
score++;
if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
return score;
l = strlen(cp) + 1;
cp += l;
cplen -= l;
}
return 0;
}
/**
* of_fdt_match - Return true if node matches a list of compatible values
*/
int of_fdt_match(struct boot_param_header *blob, unsigned long node,
const char *const *compat)
{
unsigned int tmp, score = 0;
if (!compat)
return 0;
while (*compat) {
tmp = of_fdt_is_compatible(blob, node, *compat);
if (tmp && (score == 0 || (tmp < score)))
score = tmp;
compat++;
}
return score;
}
static void *unflatten_dt_alloc(void **mem, unsigned long size,
unsigned long align)
{
void *res;
*mem = PTR_ALIGN(*mem, align);
res = *mem;
*mem += size;
return res;
}
/**
* unflatten_dt_node - Alloc and populate a device_node from the flat tree
* @blob: The parent device tree blob
* @mem: Memory chunk to use for allocating device nodes and properties
* @p: pointer to node in flat tree
* @dad: Parent struct device_node
* @allnextpp: pointer to ->allnext from last allocated device_node
* @fpsize: Size of the node path up at the current depth.
*/
static void * unflatten_dt_node(struct boot_param_header *blob,
void *mem,
void **p,
struct device_node *dad,
struct device_node ***allnextpp,
unsigned long fpsize)
{
struct device_node *np;
struct property *pp, **prev_pp = NULL;
char *pathp;
u32 tag;
unsigned int l, allocl;
int has_name = 0;
int new_format = 0;
tag = be32_to_cpup(*p);
if (tag