// SPDX-License-Identifier: GPL-2.0+

  /* pdt.c: OF PROM device tree support code.

   *
   * Paul Mackerras	August 1996.
   * Copyright (C) 1996-2005 Paul Mackerras.
   *
   *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
   *    {engebret|bergner}@us.ibm.com
   *
   *  Adapted for sparc by David S. Miller davem@davemloft.net

   *  Adapted for multiple architectures by Andres Salomon <dilinger@queued.net>

   */
  
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/errno.h>
  #include <linux/mutex.h>
  #include <linux/slab.h>
  #include <linux/of.h>

  #include <linux/of_pdt.h>

  
  static struct of_pdt_ops *of_pdt_prom_ops __initdata;

  #if defined(CONFIG_SPARC)
  unsigned int of_pdt_unique_id __initdata;
  
  #define of_pdt_incr_unique_id(p) do { \
  	(p)->unique_id = of_pdt_unique_id++; \
  } while (0)

  static char * __init of_pdt_build_full_name(struct device_node *dp)

  {

  	return build_path_component(dp);

  }

  #else /* CONFIG_SPARC */

  
  static inline void of_pdt_incr_unique_id(void *p) { }
  static inline void irq_trans_init(struct device_node *dp) { }

  static char * __init of_pdt_build_full_name(struct device_node *dp)

  {

  	static int failsafe_id = 0; /* for generating unique names on failure */

  	const char *name;
  	char path[256];

  	char *buf;
  	int len;

  	if (!of_pdt_prom_ops->pkg2path(dp->phandle, path, sizeof(path), &len)) {
  		name = kbasename(path);
  		buf = prom_early_alloc(strlen(name) + 1);
  		strcpy(buf, name);
  		return buf;
  	}

  	name = of_get_property(dp, "name", &len);
  	buf = prom_early_alloc(len + 16);
  	sprintf(buf, "%s@unknown%i", name, failsafe_id++);

  	pr_err("%s: pkg2path failed; assigning %s
  ", __func__, buf);
  	return buf;

  }
  
  #endif /* !CONFIG_SPARC */

  static struct property * __init of_pdt_build_one_prop(phandle node, char *prev,

  					       char *special_name,
  					       void *special_val,
  					       int special_len)
  {
  	static struct property *tmp = NULL;
  	struct property *p;

  	int err;

  
  	if (tmp) {
  		p = tmp;
  		memset(p, 0, sizeof(*p) + 32);
  		tmp = NULL;
  	} else {
  		p = prom_early_alloc(sizeof(struct property) + 32);

  		of_pdt_incr_unique_id(p);

  	}
  
  	p->name = (char *) (p + 1);
  	if (special_name) {
  		strcpy(p->name, special_name);
  		p->length = special_len;
  		p->value = prom_early_alloc(special_len);
  		memcpy(p->value, special_val, special_len);
  	} else {

  		err = of_pdt_prom_ops->nextprop(node, prev, p->name);
  		if (err) {

  			tmp = p;
  			return NULL;
  		}

  		p->length = of_pdt_prom_ops->getproplen(node, p->name);

  		if (p->length <= 0) {
  			p->length = 0;
  		} else {
  			int len;
  
  			p->value = prom_early_alloc(p->length + 1);

  			len = of_pdt_prom_ops->getproperty(node, p->name,
  					p->value, p->length);

  			if (len <= 0)
  				p->length = 0;
  			((unsigned char *)p->value)[p->length] = '\0';
  		}
  	}
  	return p;
  }

  static struct property * __init of_pdt_build_prop_list(phandle node)

  {
  	struct property *head, *tail;

  	head = tail = of_pdt_build_one_prop(node, NULL,

  				     ".node", &node, sizeof(node));

  	tail->next = of_pdt_build_one_prop(node, NULL, NULL, NULL, 0);

  	tail = tail->next;
  	while(tail) {

  		tail->next = of_pdt_build_one_prop(node, tail->name,

  					    NULL, NULL, 0);
  		tail = tail->next;
  	}
  
  	return head;
  }

  static char * __init of_pdt_get_one_property(phandle node, const char *name)

  {
  	char *buf = "<NULL>";
  	int len;

  	len = of_pdt_prom_ops->getproplen(node, name);

  	if (len > 0) {
  		buf = prom_early_alloc(len);

  		len = of_pdt_prom_ops->getproperty(node, name, buf, len);

  	}
  
  	return buf;
  }

  static struct device_node * __init of_pdt_create_node(phandle node,

  						    struct device_node *parent)
  {
  	struct device_node *dp;
  
  	if (!node)
  		return NULL;
  
  	dp = prom_early_alloc(sizeof(*dp));

  	of_node_init(dp);

  	of_pdt_incr_unique_id(dp);

  	dp->parent = parent;

  	dp->name = of_pdt_get_one_property(node, "name");

  	dp->phandle = node;

  	dp->properties = of_pdt_build_prop_list(node);

  	dp->full_name = of_pdt_build_full_name(dp);

  	irq_trans_init(dp);
  
  	return dp;
  }

  static struct device_node * __init of_pdt_build_tree(struct device_node *parent,

  						   phandle node)

  {
  	struct device_node *ret = NULL, *prev_sibling = NULL;
  	struct device_node *dp;
  
  	while (1) {

  		dp = of_pdt_create_node(node, parent);

  		if (!dp)
  			break;
  
  		if (prev_sibling)
  			prev_sibling->sibling = dp;
  
  		if (!ret)
  			ret = dp;
  		prev_sibling = dp;

  		dp->child = of_pdt_build_tree(dp, of_pdt_prom_ops->getchild(node));

  		node = of_pdt_prom_ops->getsibling(node);

  	}
  
  	return ret;
  }

  static void * __init kernel_tree_alloc(u64 size, u64 align)

  {
  	return prom_early_alloc(size);
  }

  void __init of_pdt_build_devicetree(phandle root_node, struct of_pdt_ops *ops)

  {

  	BUG_ON(!ops);
  	of_pdt_prom_ops = ops;

  	of_root = of_pdt_create_node(root_node, NULL);

  	of_root->full_name = "/";

  	of_root->child = of_pdt_build_tree(of_root,
  				of_pdt_prom_ops->getchild(of_root->phandle));

  	/* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */

  	of_alias_scan(kernel_tree_alloc);

  }