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     YˆÑÐƒyÇCÏ¾Ò !ß    Y// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
/*
 * libfdt - Flat Device Tree manipulation
 * Copyright (C) 2006 David Gibson, IBM Corporation.
 */
#include "libfdt_env.h"

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

#include "libfdt_internal.h"

static int fdt_sw_probe_(void *fdt)
{
	if (!can_assume(VALID_INPUT)) {
		if (fdt_magic(fdt) == FDT_MAGIC)
			return -FDT_ERR_BADSTATE;
		else if (fdt_magic(fdt) != FDT_SW_MAGIC)
			return -FDT_ERR_BADMAGIC;
	}

	return 0;
}

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

/* 'memrsv' state:	Initial state after fdt_create()
 *
 * Allowed functions:
 *	fdt_add_reservemap_entry()
 *	fdt_finish_reservemap()		[moves to 'struct' state]
 */
static int fdt_sw_probe_memrsv_(void *fdt)
{
	int err = fdt_sw_probe_(fdt);
	if (err)
		return err;

	if (!can_assume(VALID_INPUT) && fdt_off_dt_strings(fdt) != 0)
		return -FDT_ERR_BADSTATE;
	return 0;
}

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

/* 'struct' state:	Enter this state after fdt_finish_reservemap()
 *
 * Allowed functions:
 *	fdt_begin_node()
 *	fdt_end_node()
 *	fdt_property*()
 *	fdt_finish()			[moves to 'complete' state]
 */
static int fdt_sw_probe_struct_(void *fdt)
{
	int err = fdt_sw_probe_(fdt);
	if (err)
		return err;

	if (!can_assume(VALID_INPUT) &&
	    fdt_off_dt_strings(fdt) != fdt_totalsize(fdt))
		return -FDT_ERR_BADSTATE;
	return 0;
}

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

static inline uint32_t sw_flags(void *fdt)
{
	/* assert: (fdt_magic(fdt) == FDT_SW_MAGIC) */
	return fdt_last_comp_version(fdt);
}

/* 'complete' state:	Enter this state after fdt_finish()
 *
 * Allowed functions: none
 */

static void *fdt_grab_space_(void *fdt, size_t len)
{
	unsigned int offset = fdt_size_dt_struct(fdt);
	unsigned int spaceleft;

	spaceleft = fdt_totalsize(fdt) - fdt_off_dt_struct(fdt)
		- fdt_size_dt_strings(fdt);

	if ((offset + len < offset) || (offset + len > spaceleft))
		return NULL;

	fdt_set_size_dt_struct(fdt, offset + len);
	return fdt_offset_ptr_w_(fdt, offset);
}

int fdt_create_with_flags(void *buf, int bufsize, uint32_t flags)
{
	const int hdrsize = FDT_ALIGN(sizeof(struct fdt_header),
				      sizeof(struct fdt_reserve_entry));
	void *fdt = buf;

	if (bufsize < hdrsize)
		return -FDT_ERR_NOSPACE;

	if (flags & ~FDT_CREATE_FLAGS_ALL)
		return -FDT_ERR_BADFLAGS;

	memset(buf, 0, bufsize);

	/*
	 * magic and last_comp_version keep intermediate state during the fdt
	 * creation process, which is replaced with the proper FDT format by
	 * fdt_finish().
	 *
	 * flags should be accessed with sw_flags().
	 */
	fdt_set_magic(fdt, FDT_SW_MAGIC);
	fdt_set_version(fdt, FDT_LAST_SUPPORTED_VERSION);
	fdt_set_last_comp_version(fdt, flags);

	fdt_set_totalsize(fdt,  bufsize);

	fdt_set_off_mem_rsvmap(fdt, hdrsize);
	fdt_set_off_dt_struct(fdt, fdt_off_mem_rsvmap(fdt));
	fdt_set_off_dt_strings(fdt, 0);

	return 0;
}

int fdt_create(void *buf, int bufsize)
{
	return fdt_create_with_flags(buf, bufsize, 0);
}

int fdt_resize(void *fdt, void *buf, int bufsize)
{
	size_t headsize, tailsize;
	char *oldtail, *newtail;

	FDT_SW_PROBE(fdt);

	if (bufsize < 0)
		return -FDT_ERR_NOSPACE;

	headsize = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt);
	tailsize = fdt_size_dt_strings(fdt);

	if (!can_assume(VALID_DTB) &&
	    headsize + tailsize > fdt_totalsize(fdt))
		return -FDT_ERR_INTERNAL;

	if ((headsize + tailsize) > (unsigned)bufsize)
		return -FDT_ERR_NOSPACE;

	oldtail = (char *)fdt + fdt_totalsize(fdt) - tailsize;
	newtail = (char *)buf + bufsize - tailsize;

	/* Two cases to avoid clobbering data if the old and new
	 * buffers partially overlap */
	if (buf <= fdt) {
		memmove(buf, fdt, headsize);
		memmove(newtail, oldtail, tailsize);
	} else {
		memmove(newtail, oldtail, tailsize);
		memmove(buf, fdt, headsize);
	}

	fdt_set_totalsize(buf, bufsize);
	if (fdt_off_dt_strings