fdt_support.c

/*
 * (C) Copyright 2007
 * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com
 *
 * Copyright 2010-2011 Freescale Semiconductor, Inc.
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <inttypes.h>
#include <stdio_dev.h>
#include <linux/ctype.h>
#include <linux/types.h>
#include <asm/global_data.h>
#include <libfdt.h>
#include <fdt_support.h>
#include <exports.h>

/**
 * fdt_getprop_u32_default_node - Return a node's property or a default
 *
 * @fdt: ptr to device tree
 * @off: offset of node
 * @cell: cell offset in property
 * @prop: property name
 * @dflt: default value if the property isn't found
 *
 * Convenience function to return a node's property or a default value if
 * the property doesn't exist.
 */
u32 fdt_getprop_u32_default_node(const void *fdt, int off, int cell,
				const char *prop, const u32 dflt)
{
	const fdt32_t *val;
	int len;

	val = fdt_getprop(fdt, off, prop, &len);

	/* Check if property exists */
	if (!val)
		return dflt;

	/* Check if property is long enough */
	if (len < ((cell + 1) * sizeof(uint32_t)))
		return dflt;

	return fdt32_to_cpu(*val);
}

/**
 * fdt_getprop_u32_default - Find a node and return it's property or a default
 *
 * @fdt: ptr to device tree
 * @path: path of node
 * @prop: property name
 * @dflt: default value if the property isn't found
 *
 * Convenience function to find a node and return it's property or a
 * default value if it doesn't exist.
 */
u32 fdt_getprop_u32_default(const void *fdt, const char *path,
				const char *prop, const u32 dflt)
{
	int off;

	off = fdt_path_offset(fdt, path);
	if (off < 0)
		return dflt;

	return fdt_getprop_u32_default_node(fdt, off, 0, prop, dflt);
}

/**
 * fdt_find_and_setprop: Find a node and set it's property
 *
 * @fdt: ptr to device tree
 * @node: path of node
 * @prop: property name
 * @val: ptr to new value
 * @len: length of new property value
 * @create: flag to create the property if it doesn't exist
 *
 * Convenience function to directly set a property given the path to the node.
 */
int fdt_find_and_setprop(void *fdt, const char *node, const char *prop,
			 const void *val, int len, int create)
{
	int nodeoff = fdt_path_offset(fdt, node);

	if (nodeoff < 0)
		return nodeoff;

	if ((!create) && (fdt_get_property(fdt, nodeoff, prop, NULL) == NULL))
		return 0; /* create flag not set; so exit quietly */

	return fdt_setprop(fdt, nodeoff, prop, val, len);
}

/**
 * fdt_find_or_add_subnode() - find or possibly add a subnode of a given node
 *
 * @fdt: pointer to the device tree blob
 * @parentoffset: structure block offset of a node
 * @name: name of the subnode to locate
 *
 * fdt_subnode_offset() finds a subnode of the node with a given name.
 * If the subnode does not exist, it will be created.
 */
int fdt_find_or_add_subnode(void *fdt, int parentoffset, const char *name)
{
	int offset;

	offset = fdt_subnode_offset(fdt, parentoffset, name);

	if (offset == -FDT_ERR_NOTFOUND)
		offset = fdt_add_subnode(fdt, parentoffset, name);

	if (offset < 0)
		printf("%s: %s: %s\n", __func__, name, fdt_strerror(offset));

	return offset;
}

/* rename to CONFIG_OF_STDOUT_PATH ? */
#if defined(OF_STDOUT_PATH)
static int fdt_fixup_stdout(void *fdt, int chosenoff)
{
	return fdt_setprop(fdt, chosenoff, "linux,stdout-path",
			      OF_STDOUT_PATH, strlen(OF_STDOUT_PATH) + 1);
}
#elif defined(CONFIG_OF_STDOUT_VIA_ALIAS) && defined(CONFIG_CONS_INDEX)
static void fdt_fill_multisername(char *sername, size_t maxlen)
{
	const char *outname = stdio_devices[stdout]->name;

	if (strcmp(outname, "serial") > 0)
		strncpy(sername, outname, maxlen);

	/* eserial? */
	if (strcmp(outname + 1, "serial") > 0)
		strncpy(sername, outname + 1, maxlen);
}

static int fdt_fixup_stdout(void *fdt, int chosenoff)
{
	int err;
	int aliasoff;
	char sername[9] = { 0 };
	const void *path;
	int len;
	char tmp[256]; /* long enough */

	fdt_fill_multisername(sername, sizeof(sername) - 1);
	if (!sername[0])
		sprintf(sername, "serial%d", CONFIG_CONS_INDEX - 1);

	aliasoff = fdt_path_offset(fdt, "/aliases");
	if (aliasoff < 0) {
		err = aliasoff;
		goto error;
	}

	path = fdt_getprop(fdt, aliasoff, sername, &len);
	if (!path) {
		err = len;
		goto error;
	}

	/* fdt_setprop may break "path" so we copy it to tmp buffer */
	memcpy(tmp, path, len);

	err = fdt_setprop(fdt, chosenoff, "linux,stdout-path", tmp, len);
error:
	if (err < 0)
		printf("WARNING: could not set linux,stdout-path %s.\n",
		       fdt_strerror(err));

	return err;
}
#else
static int fdt_fixup_stdout(void *fdt, int chosenoff)
{
	return 0;
}
#endif

static inline int fdt_setprop_uxx(void *fdt, int nodeoffset, const char *name,
				  uint64_t val, int is_u64)
{
	if (is_u64)
		return fdt_setprop_u64(fdt, nodeoffset, name, val);
	else
		return fdt_setprop_u32(fdt, nodeoffset, name, (uint32_t)val);
}


int fdt_initrd(void *fdt, ulong initrd_start, ulong initrd_end)
{
	int   nodeoffset;