/*
 * 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/of.h>
#include <linux/of_fdt.h>
#include <linux/of_reserved_mem.h>
#include <linux/sizes.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/libfdt.h>
#include <linux/debugfs.h>
#include <linux/serial_core.h>

#include <asm/setup.h>  /* for COMMAND_LINE_SIZE */
#include <asm/page.h>

/**
 * 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(const void *blob,
		      unsigned long node, const char *compat)
{
	const char *cp;
	int cplen;
	unsigned long l, score = 0;

	cp = fdt_getprop(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(const void *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(void *blob,
				void *mem,
				int *poffset,
				struct device_node *dad,
				struct device_node ***allnextpp,
				unsigned long fpsize)
{
	const __be32 *p;
	struct device_node *np;
	struct property *pp, **prev_pp = NULL;
	const char *pathp;
	unsigned int l, allocl;
	static int depth = 0;
	int old_depth;
	int offset;
	int has_name = 0;
	int new_format = 0;

	pathp = fdt_get_name(blob, *poffset, &l);
	if (!pathp)
		return mem;

	allocl = l++;

	/* version 0x10 has a more compact unit name here instead of the full
	 * path. we accumulate the full path size using "fpsize", we'll rebuild
	 * it later. We detect this because the first character of the name is
	 * not '/'.
	 */
	if ((*pathp) != '/') {
		new_format = 1;
		if (fpsize == 0) {
			/* root node: special case. fpsize accounts for path
			 * plus terminating zero. root node only has '/', so
			 * fpsize should be 2, but we want to avoid the first
			 * level nodes to have two '/' so we use fpsize 1 here
			 */
			fpsize = 1;
			allocl = 2;
			l = 1;
			pathp = "";
		} else {
			/* account for '/' and path size minus terminal 0
			 * already in 'l'
			 */
			fpsize += l;
			allocl = fpsize;
		}
	}

	np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
				__alignof__(struct device_node));
	if (allnextpp) {
		char *fn;
		of_node_init(np);
		np->full_name = fn = ((char *)np) + sizeof(*np);
		if (new_format) {
			/* rebuild full path for new format */
			if (dad && dad->parent) {
				strcp