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 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Procedures for creating, accessing and interpreting the device tree.
  *
  * 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 and sparc64 by David S. Miller davem@davemloft.net
  *
  *  Reconsolidated from arch/x/kernel/prom.c by Stephen Rothwell and
  *  Grant Likely.
  */
 
 #define pr_fmt(fmt) "OF: " fmt
 
 #include <linux/console.h>
 #include <linux/ctype.h>
 #include <linux/cpu.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/of_graph.h>
 #include <linux/spinlock.h>
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/proc_fs.h>
 
 #include "of_private.h"
 
 LIST_HEAD(aliases_lookup);
 
 struct device_node *of_root;
 EXPORT_SYMBOL(of_root);
 struct device_node *of_chosen;
 EXPORT_SYMBOL(of_chosen);
 struct device_node *of_aliases;
 struct device_node *of_stdout;
 static const char *of_stdout_options;
 
 struct kset *of_kset;
 
 /*
  * Used to protect the of_aliases, to hold off addition of nodes to sysfs.
  * This mutex must be held whenever modifications are being made to the
  * device tree. The of_{attach,detach}_node() and
  * of_{add,remove,update}_property() helpers make sure this happens.
  */
 DEFINE_MUTEX(of_mutex);
 
 /* use when traversing tree through the child, sibling,
  * or parent members of struct device_node.
  */
 DEFINE_RAW_SPINLOCK(devtree_lock);
 
 bool of_node_name_eq(const struct device_node *np, const char *name)
 {
     const char *node_name;
     size_t len;
 
     if (!np)
         return false;
 
     node_name = kbasename(np->full_name);
     len = strchrnul(node_name, '@') - node_name;
 
     return (strlen(name) == len) && (strncmp(node_name, name, len) == 0);
 }
 EXPORT_SYMBOL(of_node_name_eq);
 
 bool of_node_name_prefix(const struct device_node *np, const char *prefix)
 {
     if (!np)
         return false;
 
     return strncmp(kbasename(np->full_name), prefix, strlen(prefix)) == 0;
 }
 EXPORT_SYMBOL(of_node_name_prefix);
 
 static bool __of_node_is_type(const struct device_node *np, const char *type)
 {
     const char *match = __of_get_property(np, "device_type", NULL);
 
     return np && match && type && !strcmp(match, type);
 }
 
 int of_bus_n_addr_cells(struct device_node *np)
 {
     u32 cells;
 
     for (; np; np = np->parent)
         if (!of_property_read_u32(np, "#address-cells", &cells))
             return cells;
 
     /* No #address-cells property for the root node */
     return OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
 }
 
 int of_n_addr_cells(struct device_node *np)
 {
     if (np->parent)
         np = np->parent;
 
     return of_bus_n_addr_cells(np);
 }
 EXPORT_SYMBOL(of_n_addr_cells);
 
 int of_bus_n_size_cells(struct device_node *np)
 {
     u32 cells;
 
     for (; np; np = np->parent)
         if (!of_property_read_u32(np, "#size-cells", &cells))
             return cells;
 
     /* No #size-cells property for the root node */
     return OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
 }
 
 int of_n_size_cells(struct device_node *np)
 {
     if (np->parent)
         np = np->parent;
 
     return of_bus_n_size_cells(np);
 }
 EXPORT_SYMBOL(of_n_size_cells);
 
 #ifdef CONFIG_NUMA
 int __weak of_node_to_nid(struct device_node *np)
 {
     return NUMA_NO_NODE;
 }
 #endif
 
 #define OF_PHANDLE_CACHE_BITS   7
 #define OF_PHANDLE_CACHE_SZ BIT(OF_PHANDLE_CACHE_BITS)
 
 static struct device_node *phandle_cache[OF_PHANDLE_CACHE_SZ];
 
 static u32 of_phandle_cache_hash(phandle handle)
 {
     return hash_32(handle, OF_PHANDLE_CACHE_BITS);
 }
 
 /*
  * Caller must hold devtree_lock.
  */
 void __of_phandle_cache_inv_entry(phandle handle)
 {
     u32 handle_hash;
     struct device_node *np;
 
     if (!handle)
         return;
 
     handle_hash = of_phandle_cache_hash(handle);
 
     np = phandle_cache[handle_hash];
     if (np && handle == np->phandle)
         phandle_cache[handle_hash] = NULL;
 }
 
 void __init of_core_init(void)
 {
     struct device_node *np;
 
 
     /* Create the kset, and register existing nodes */
     mutex_lock(&of_mutex);
     of_kset = kset_create_and_add("devicetree", NULL, firmware_kobj);
     if (!of_kset) {
         mutex_unlock(&of_mutex);
         pr_err("failed to register existing nodes\n");
         return;
     }
     for_each_of_allnodes(np) {
         __of_attach_node_sysfs(np);
         if (np->phandle && !phandle_cache[of_phandle_cache_hash(np->phandle)])
             phandle_cache[of_phandle_cache_hash(np->phandle)] = np;
     }
     mutex_unlock(&of_mutex);
 
     /* Symlink in /proc as required by userspace ABI */
     if (of_root)
         proc_symlink("device-tree", NULL, "/sys/firmware/devicetree/base");
 }
 
 static struct property *__of_find_property(const struct device_node *np,
                        const char *name, int *lenp)
 {
     struct property *pp;
 
     if (!np)
         return NULL;
 
     for (pp = np->properties; pp; pp = pp->next) {
         if (of_prop_cmp(pp->name, name) == 0) {
             if (lenp)
                 *lenp = pp->length;
             break;
         }
     }
 
     return pp;
 }
 
 struct property *of_find_property(const struct device_node *np,
                   const char *name,
                   int *lenp)
 {
     struct property *pp;
     unsigned long flags;
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     pp = __of_find_property(np, name, lenp);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
 
     return pp;
 }
 EXPORT_SYMBOL(of_find_property);
 
 struct device_node *__of_find_all_nodes(struct device_node *prev)
 {
     struct device_node *np;
     if (!prev) {
         np = of_root;
     } else if (prev->child) {
         np = prev->child;
     } else {
         /* Walk back up looking for a sibling, or the end of the structure */
         np = prev;
         while (np->parent && !np->sibling)
             np = np->parent;
         np = np->sibling; /* Might be null at the end of the tree */
     }
     return np;
 }
 
 /**
  * of_find_all_nodes - Get next node in global list
  * @prev:   Previous node or NULL to start iteration
  *      of_node_put() will be called on it
  *
  * Return: A node pointer with refcount incremented, use
  * of_node_put() on it when done.
  */
 struct device_node *of_find_all_nodes(struct device_node *prev)
 {
     struct device_node *np;
     unsigned long flags;
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     np = __of_find_all_nodes(prev);
     of_node_get(np);
     of_node_put(prev);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
     return np;
 }
 EXPORT_SYMBOL(of_find_all_nodes);
 
 /*
  * Find a property with a given name for a given node
  * and return the value.
  */
 const void *__of_get_property(const struct device_node *np,
                   const char *name, int *lenp)
 {
     struct property *pp = __of_find_property(np, name, lenp);
 
     return pp ? pp->value : NULL;
 }
 
 /*
  * Find a property with a given name for a given node
  * and return the value.
  */
 const void *of_get_property(const struct device_node *np, const char *name,
                 int *lenp)
 {
     struct property *pp = of_find_property(np, name, lenp);
 
     return pp ? pp->value : NULL;
 }
 EXPORT_SYMBOL(of_get_property);
 
 /**
  * of_get_cpu_hwid - Get the hardware ID from a CPU device node
  *
  * @cpun: CPU number(logical index) for which device node is required
  * @thread: The local thread number to get the hardware ID for.
  *
  * Return: The hardware ID for the CPU node or ~0ULL if not found.
  */
 u64 of_get_cpu_hwid(struct device_node *cpun, unsigned int thread)
 {
     const __be32 *cell;
     int ac, len;
 
     ac = of_n_addr_cells(cpun);
     cell = of_get_property(cpun, "reg", &len);
     if (!cell || !ac || ((sizeof(*cell) * ac * (thread + 1)) > len))
         return ~0ULL;
 
     cell += ac * thread;
     return of_read_number(cell, ac);
 }
 
 /*
  * arch_match_cpu_phys_id - Match the given logical CPU and physical id
  *
  * @cpu: logical cpu index of a core/thread
  * @phys_id: physical identifier of a core/thread
  *
  * CPU logical to physical index mapping is architecture specific.
  * However this __weak function provides a default match of physical
  * id to logical cpu index. phys_id provided here is usually values read
  * from the device tree which must match the hardware internal registers.
  *
  * Returns true if the physical identifier and the logical cpu index
  * correspond to the same core/thread, false otherwise.
  */
 bool __weak arch_match_cpu_phys_id(int cpu, u64 phys_id)
 {
     return (u32)phys_id == cpu;
 }
 
 /*
  * Checks if the given "prop_name" property holds the physical id of the
  * core/thread corresponding to the logical cpu 'cpu'. If 'thread' is not
  * NULL, local thread number within the core is returned in it.
  */
 static bool __of_find_n_match_cpu_property(struct device_node *cpun,
             const char *prop_name, int cpu, unsigned int *thread)
 {
     const __be32 *cell;
     int ac, prop_len, tid;
     u64 hwid;
 
     ac = of_n_addr_cells(cpun);
     cell = of_get_property(cpun, prop_name, &prop_len);
     if (!cell && !ac && arch_match_cpu_phys_id(cpu, 0))
         return true;
     if (!cell || !ac)
         return false;
     prop_len /= sizeof(*cell) * ac;
     for (tid = 0; tid < prop_len; tid++) {
         hwid = of_read_number(cell, ac);
         if (arch_match_cpu_phys_id(cpu, hwid)) {
             if (thread)
                 *thread = tid;
             return true;
         }
         cell += ac;
     }
     return false;
 }
 
 /*
  * arch_find_n_match_cpu_physical_id - See if the given device node is
  * for the cpu corresponding to logical cpu 'cpu'.  Return true if so,
  * else false.  If 'thread' is non-NULL, the local thread number within the
  * core is returned in it.
  */
 bool __weak arch_find_n_match_cpu_physical_id(struct device_node *cpun,
                           int cpu, unsigned int *thread)
 {
     /* Check for non-standard "ibm,ppc-interrupt-server#s" property
      * for thread ids on PowerPC. If it doesn't exist fallback to
      * standard "reg" property.
      */
     if (IS_ENABLED(CONFIG_PPC) &&
         __of_find_n_match_cpu_property(cpun,
                        "ibm,ppc-interrupt-server#s",
                        cpu, thread))
         return true;
 
     return __of_find_n_match_cpu_property(cpun, "reg", cpu, thread);
 }
 
 /**
  * of_get_cpu_node - Get device node associated with the given logical CPU
  *
  * @cpu: CPU number(logical index) for which device node is required
  * @thread: if not NULL, local thread number within the physical core is
  *          returned
  *
  * The main purpose of this function is to retrieve the device node for the
  * given logical CPU index. It should be used to initialize the of_node in
  * cpu device. Once of_node in cpu device is populated, all the further
  * references can use that instead.
  *
  * CPU logical to physical index mapping is architecture specific and is built
  * before booting secondary cores. This function uses arch_match_cpu_phys_id
  * which can be overridden by architecture specific implementation.
  *
  * Return: A node pointer for the logical cpu with refcount incremented, use
  * of_node_put() on it when done. Returns NULL if not found.
  */
 struct device_node *of_get_cpu_node(int cpu, unsigned int *thread)
 {
     struct device_node *cpun;
 
     for_each_of_cpu_node(cpun) {
         if (arch_find_n_match_cpu_physical_id(cpun, cpu, thread))
             return cpun;
     }
     return NULL;
 }
 EXPORT_SYMBOL(of_get_cpu_node);
 
 /**
  * of_cpu_node_to_id: Get the logical CPU number for a given device_node
  *
  * @cpu_node: Pointer to the device_node for CPU.
  *
  * Return: The logical CPU number of the given CPU device_node or -ENODEV if the
  * CPU is not found.
  */
 int of_cpu_node_to_id(struct device_node *cpu_node)
 {
     int cpu;
     bool found = false;
     struct device_node *np;
 
     for_each_possible_cpu(cpu) {
         np = of_cpu_device_node_get(cpu);
         found = (cpu_node == np);
         of_node_put(np);
         if (found)
             return cpu;
     }
 
     return -ENODEV;
 }
 EXPORT_SYMBOL(of_cpu_node_to_id);
 
 /**
  * of_get_cpu_state_node - Get CPU's idle state node at the given index
  *
  * @cpu_node: The device node for the CPU
  * @index: The index in the list of the idle states
  *
  * Two generic methods can be used to describe a CPU's idle states, either via
  * a flattened description through the "cpu-idle-states" binding or via the
  * hierarchical layout, using the "power-domains" and the "domain-idle-states"
  * bindings. This function check for both and returns the idle state node for
  * the requested index.
  *
  * Return: An idle state node if found at @index. The refcount is incremented
  * for it, so call of_node_put() on it when done. Returns NULL if not found.
  */
 struct device_node *of_get_cpu_state_node(struct device_node *cpu_node,
                       int index)
 {
     struct of_phandle_args args;
     int err;
 
     err = of_parse_phandle_with_args(cpu_node, "power-domains",
                     "#power-domain-cells", 0, &args);
     if (!err) {
         struct device_node *state_node =
             of_parse_phandle(args.np, "domain-idle-states", index);
 
         of_node_put(args.np);
         if (state_node)
             return state_node;
     }
 
     return of_parse_phandle(cpu_node, "cpu-idle-states", index);
 }
 EXPORT_SYMBOL(of_get_cpu_state_node);
 
 /**
  * __of_device_is_compatible() - Check if the node matches given constraints
  * @device: pointer to node
  * @compat: required compatible string, NULL or "" for any match
  * @type: required device_type value, NULL or "" for any match
  * @name: required node name, NULL or "" for any match
  *
  * Checks if the given @compat, @type and @name strings match the
  * properties of the given @device. A constraints can be skipped by
  * passing NULL or an empty string as the constraint.
  *
  * Returns 0 for no match, and a positive integer on match. The return
  * value is a relative score with larger values indicating better
  * matches. The score is weighted for the most specific compatible value
  * to get the highest score. Matching type is next, followed by matching
  * name. Practically speaking, this results in the following priority
  * order for matches:
  *
  * 1. specific compatible && type && name
  * 2. specific compatible && type
  * 3. specific compatible && name
  * 4. specific compatible
  * 5. general compatible && type && name
  * 6. general compatible && type
  * 7. general compatible && name
  * 8. general compatible
  * 9. type && name
  * 10. type
  * 11. name
  */
 static int __of_device_is_compatible(const struct device_node *device,
                      const char *compat, const char *type, const char *name)
 {
     struct property *prop;
     const char *cp;
     int index = 0, score = 0;
 
     /* Compatible match has highest priority */
     if (compat && compat[0]) {
         prop = __of_find_property(device, "compatible", NULL);
         for (cp = of_prop_next_string(prop, NULL); cp;
              cp = of_prop_next_string(prop, cp), index++) {
             if (of_compat_cmp(cp, compat, strlen(compat)) == 0) {
                 score = INT_MAX/2 - (index << 2);
                 break;
             }
         }
         if (!score)
             return 0;
     }
 
     /* Matching type is better than matching name */
     if (type && type[0]) {
         if (!__of_node_is_type(device, type))
             return 0;
         score += 2;
     }
 
     /* Matching name is a bit better than not */
     if (name && name[0]) {
         if (!of_node_name_eq(device, name))
             return 0;
         score++;
     }
 
     return score;
 }
 
 /** Checks if the given "compat" string matches one of the strings in
  * the device's "compatible" property
  */
 int of_device_is_compatible(const struct device_node *device,
         const char *compat)
 {
     unsigned long flags;
     int res;
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     res = __of_device_is_compatible(device, compat, NULL, NULL);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
     return res;
 }
 EXPORT_SYMBOL(of_device_is_compatible);
 
 /** Checks if the device is compatible with any of the entries in
  *  a NULL terminated array of strings. Returns the best match
  *  score or 0.
  */
 int of_device_compatible_match(struct device_node *device,
                    const char *const *compat)
 {
     unsigned int tmp, score = 0;
 
     if (!compat)
         return 0;
 
     while (*compat) {
         tmp = of_device_is_compatible(device, *compat);
         if (tmp > score)
             score = tmp;
         compat++;
     }
 
     return score;
 }
 
 /**
  * of_machine_is_compatible - Test root of device tree for a given compatible value
  * @compat: compatible string to look for in root node's compatible property.
  *
  * Return: A positive integer if the root node has the given value in its
  * compatible property.
  */
 int of_machine_is_compatible(const char *compat)
 {
     struct device_node *root;
     int rc = 0;
 
     root = of_find_node_by_path("/");
     if (root) {
         rc = of_device_is_compatible(root, compat);
         of_node_put(root);
     }
     return rc;
 }
 EXPORT_SYMBOL(of_machine_is_compatible);
 
 /**
  *  __of_device_is_available - check if a device is available for use
  *
  *  @device: Node to check for availability, with locks already held
  *
  *  Return: True if the status property is absent or set to "okay" or "ok",
  *  false otherwise
  */
 static bool __of_device_is_available(const struct device_node *device)
 {
     const char *status;
     int statlen;
 
     if (!device)
         return false;
 
     status = __of_get_property(device, "status", &statlen);
     if (status == NULL)
         return true;
 
     if (statlen > 0) {
         if (!strcmp(status, "okay") || !strcmp(status, "ok"))
             return true;
     }
 
     return false;
 }
 
 /**
  *  of_device_is_available - check if a device is available for use
  *
  *  @device: Node to check for availability
  *
  *  Return: True if the status property is absent or set to "okay" or "ok",
  *  false otherwise
  */
 bool of_device_is_available(const struct device_node *device)
 {
     unsigned long flags;
     bool res;
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     res = __of_device_is_available(device);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
     return res;
 
 }
 EXPORT_SYMBOL(of_device_is_available);
 
 /**
  *  __of_device_is_fail - check if a device has status "fail" or "fail-..."
  *
  *  @device: Node to check status for, with locks already held
  *
  *  Return: True if the status property is set to "fail" or "fail-..." (for any
  *  error code suffix), false otherwise
  */
 static bool __of_device_is_fail(const struct device_node *device)
 {
     const char *status;
 
     if (!device)
         return false;
 
     status = __of_get_property(device, "status", NULL);
     if (status == NULL)
         return false;
 
     return !strcmp(status, "fail") || !strncmp(status, "fail-", 5);
 }
 
 /**
  *  of_device_is_big_endian - check if a device has BE registers
  *
  *  @device: Node to check for endianness
  *
  *  Return: True if the device has a "big-endian" property, or if the kernel
  *  was compiled for BE *and* the device has a "native-endian" property.
  *  Returns false otherwise.
  *
  *  Callers would nominally use ioread32be/iowrite32be if
  *  of_device_is_big_endian() == true, or readl/writel otherwise.
  */
 bool of_device_is_big_endian(const struct device_node *device)
 {
     if (of_property_read_bool(device, "big-endian"))
         return true;
     if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) &&
         of_property_read_bool(device, "native-endian"))
         return true;
     return false;
 }
 EXPORT_SYMBOL(of_device_is_big_endian);
 
 /**
  * of_get_parent - Get a node's parent if any
  * @node:   Node to get parent
  *
  * Return: A node pointer with refcount incremented, use
  * of_node_put() on it when done.
  */
 struct device_node *of_get_parent(const struct device_node *node)
 {
     struct device_node *np;
     unsigned long flags;
 
     if (!node)
         return NULL;
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     np = of_node_get(node->parent);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
     return np;
 }
 EXPORT_SYMBOL(of_get_parent);
 
 /**
  * of_get_next_parent - Iterate to a node's parent
  * @node:   Node to get parent of
  *
  * This is like of_get_parent() except that it drops the
  * refcount on the passed node, making it suitable for iterating
  * through a node's parents.
  *
  * Return: A node pointer with refcount incremented, use
  * of_node_put() on it when done.
  */
 struct device_node *of_get_next_parent(struct device_node *node)
 {
     struct device_node *parent;
     unsigned long flags;
 
     if (!node)
         return NULL;
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     parent = of_node_get(node->parent);
     of_node_put(node);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
     return parent;
 }
 EXPORT_SYMBOL(of_get_next_parent);
 
 static struct device_node *__of_get_next_child(const struct device_node *node,
                         struct device_node *prev)
 {
     struct device_node *next;
 
     if (!node)
         return NULL;
 
     next = prev ? prev->sibling : node->child;
     of_node_get(next);
     of_node_put(prev);
     return next;
 }
 #define __for_each_child_of_node(parent, child) \
     for (child = __of_get_next_child(parent, NULL); child != NULL; \
          child = __of_get_next_child(parent, child))
 
 /**
  * of_get_next_child - Iterate a node childs
  * @node:   parent node
  * @prev:   previous child of the parent node, or NULL to get first
  *
  * Return: A node pointer with refcount incremented, use of_node_put() on
  * it when done. Returns NULL when prev is the last child. Decrements the
  * refcount of prev.
  */
 struct device_node *of_get_next_child(const struct device_node *node,
     struct device_node *prev)
 {
     struct device_node *next;
     unsigned long flags;
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     next = __of_get_next_child(node, prev);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
     return next;
 }
 EXPORT_SYMBOL(of_get_next_child);
 
 /**
  * of_get_next_available_child - Find the next available child node
  * @node:   parent node
  * @prev:   previous child of the parent node, or NULL to get first
  *
  * This function is like of_get_next_child(), except that it
  * automatically skips any disabled nodes (i.e. status = "disabled").
  */
 struct device_node *of_get_next_available_child(const struct device_node *node,
     struct device_node *prev)
 {
     struct device_node *next;
     unsigned long flags;
 
     if (!node)
         return NULL;
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     next = prev ? prev->sibling : node->child;
     for (; next; next = next->sibling) {
         if (!__of_device_is_available(next))
             continue;
         if (of_node_get(next))
             break;
     }
     of_node_put(prev);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
     return next;
 }
 EXPORT_SYMBOL(of_get_next_available_child);
 
 /**
  * of_get_next_cpu_node - Iterate on cpu nodes
  * @prev:   previous child of the /cpus node, or NULL to get first
  *
  * Unusable CPUs (those with the status property set to "fail" or "fail-...")
  * will be skipped.
  *
  * Return: A cpu node pointer with refcount incremented, use of_node_put()
  * on it when done. Returns NULL when prev is the last child. Decrements
  * the refcount of prev.
  */
 struct device_node *of_get_next_cpu_node(struct device_node *prev)
 {
     struct device_node *next = NULL;
     unsigned long flags;
     struct device_node *node;
 
     if (!prev)
         node = of_find_node_by_path("/cpus");
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     if (prev)
         next = prev->sibling;
     else if (node) {
         next = node->child;
         of_node_put(node);
     }
     for (; next; next = next->sibling) {
         if (__of_device_is_fail(next))
             continue;
         if (!(of_node_name_eq(next, "cpu") ||
               __of_node_is_type(next, "cpu")))
             continue;
         if (of_node_get(next))
             break;
     }
     of_node_put(prev);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
     return next;
 }
 EXPORT_SYMBOL(of_get_next_cpu_node);
 
 /**
  * of_get_compatible_child - Find compatible child node
  * @parent: parent node
  * @compatible: compatible string
  *
  * Lookup child node whose compatible property contains the given compatible
  * string.
  *
  * Return: a node pointer with refcount incremented, use of_node_put() on it
  * when done; or NULL if not found.
  */
 struct device_node *of_get_compatible_child(const struct device_node *parent,
                 const char *compatible)
 {
     struct device_node *child;
 
     for_each_child_of_node(parent, child) {
         if (of_device_is_compatible(child, compatible))
             break;
     }
 
     return child;
 }
 EXPORT_SYMBOL(of_get_compatible_child);
 
 /**
  * of_get_child_by_name - Find the child node by name for a given parent
  * @node:   parent node
  * @name:   child name to look for.
  *
  * This function looks for child node for given matching name
  *
  * Return: A node pointer if found, with refcount incremented, use
  * of_node_put() on it when done.
  * Returns NULL if node is not found.
  */
 struct device_node *of_get_child_by_name(const struct device_node *node,
                 const char *name)
 {
     struct device_node *child;
 
     for_each_child_of_node(node, child)
         if (of_node_name_eq(child, name))
             break;
     return child;
 }
 EXPORT_SYMBOL(of_get_child_by_name);
 
 struct device_node *__of_find_node_by_path(struct device_node *parent,
                         const char *path)
 {
     struct device_node *child;
     int len;
 
     len = strcspn(path, "/:");
     if (!len)
         return NULL;
 
     __for_each_child_of_node(parent, child) {
         const char *name = kbasename(child->full_name);
         if (strncmp(path, name, len) == 0 && (strlen(name) == len))
             return child;
     }
     return NULL;
 }
 
 struct device_node *__of_find_node_by_full_path(struct device_node *node,
                         const char *path)
 {
     const char *separator = strchr(path, ':');
 
     while (node && *path == '/') {
         struct device_node *tmp = node;
 
         path++; /* Increment past '/' delimiter */
         node = __of_find_node_by_path(node, path);
         of_node_put(tmp);
         path = strchrnul(path, '/');
         if (separator && separator < path)
             break;
     }
     return node;
 }
 
 /**
  * of_find_node_opts_by_path - Find a node matching a full OF path
  * @path: Either the full path to match, or if the path does not
  *       start with '/', the name of a property of the /aliases
  *       node (an alias).  In the case of an alias, the node
  *       matching the alias' value will be returned.
  * @opts: Address of a pointer into which to store the start of
  *       an options string appended to the end of the path with
  *       a ':' separator.
  *
  * Valid paths:
  *  * /foo/bar  Full path
  *  * foo   Valid alias
  *  * foo/bar   Valid alias + relative path
  *
  * Return: A node pointer with refcount incremented, use
  * of_node_put() on it when done.
  */
 struct device_node *of_find_node_opts_by_path(const char *path, const char **opts)
 {
     struct device_node *np = NULL;
     struct property *pp;
     unsigned long flags;
     const char *separator = strchr(path, ':');
 
     if (opts)
         *opts = separator ? separator + 1 : NULL;
 
     if (strcmp(path, "/") == 0)
         return of_node_get(of_root);
 
     /* The path could begin with an alias */
     if (*path != '/') {
         int len;
         const char *p = separator;
 
         if (!p)
             p = strchrnul(path, '/');
         len = p - path;
 
         /* of_aliases must not be NULL */
         if (!of_aliases)
             return NULL;
 
         for_each_property_of_node(of_aliases, pp) {
             if (strlen(pp->name) == len && !strncmp(pp->name, path, len)) {
                 np = of_find_node_by_path(pp->value);
                 break;
             }
         }
         if (!np)
             return NULL;
         path = p;
     }
 
     /* Step down the tree matching path components */
     raw_spin_lock_irqsave(&devtree_lock, flags);
     if (!np)
         np = of_node_get(of_root);
     np = __of_find_node_by_full_path(np, path);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
     return np;
 }
 EXPORT_SYMBOL(of_find_node_opts_by_path);
 
 /**
  * of_find_node_by_name - Find a node by its "name" property
  * @from:   The node to start searching from or NULL; the node
  *      you pass will not be searched, only the next one
  *      will. Typically, you pass what the previous call
  *      returned. of_node_put() will be called on @from.
  * @name:   The name string to match against
  *
  * Return: A node pointer with refcount incremented, use
  * of_node_put() on it when done.
  */
 struct device_node *of_find_node_by_name(struct device_node *from,
     const char *name)
 {
     struct device_node *np;
     unsigned long flags;
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     for_each_of_allnodes_from(from, np)
         if (of_node_name_eq(np, name) && of_node_get(np))
             break;
     of_node_put(from);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
     return np;
 }
 EXPORT_SYMBOL(of_find_node_by_name);
 
 /**
  * of_find_node_by_type - Find a node by its "device_type" property
  * @from:   The node to start searching from, or NULL to start searching
  *      the entire device tree. The node you pass will not be
  *      searched, only the next one will; typically, you pass
  *      what the previous call returned. of_node_put() will be
  *      called on from for you.
  * @type:   The type string to match against
  *
  * Return: A node pointer with refcount incremented, use
  * of_node_put() on it when done.
  */
 struct device_node *of_find_node_by_type(struct device_node *from,
     const char *type)
 {
     struct device_node *np;
     unsigned long flags;
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     for_each_of_allnodes_from(from, np)
         if (__of_node_is_type(np, type) && of_node_get(np))
             break;
     of_node_put(from);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
     return np;
 }
 EXPORT_SYMBOL(of_find_node_by_type);
 
 /**
  * of_find_compatible_node - Find a node based on type and one of the
  *                                tokens in its "compatible" property
  * @from:   The node to start searching from or NULL, the node
  *      you pass will not be searched, only the next one
  *      will; typically, you pass what the previous call
  *      returned. of_node_put() will be called on it
  * @type:   The type string to match "device_type" or NULL to ignore
  * @compatible: The string to match to one of the tokens in the device
  *      "compatible" list.
  *
  * Return: A node pointer with refcount incremented, use
  * of_node_put() on it when done.
  */
 struct device_node *of_find_compatible_node(struct device_node *from,
     const char *type, const char *compatible)
 {
     struct device_node *np;
     unsigned long flags;
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     for_each_of_allnodes_from(from, np)
         if (__of_device_is_compatible(np, compatible, type, NULL) &&
             of_node_get(np))
             break;
     of_node_put(from);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
     return np;
 }
 EXPORT_SYMBOL(of_find_compatible_node);
 
 /**
  * of_find_node_with_property - Find a node which has a property with
  *                              the given name.
  * @from:   The node to start searching from or NULL, the node
  *      you pass will not be searched, only the next one
  *      will; typically, you pass what the previous call
  *      returned. of_node_put() will be called on it
  * @prop_name:  The name of the property to look for.
  *
  * Return: A node pointer with refcount incremented, use
  * of_node_put() on it when done.
  */
 struct device_node *of_find_node_with_property(struct device_node *from,
     const char *prop_name)
 {
     struct device_node *np;
     struct property *pp;
     unsigned long flags;
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     for_each_of_allnodes_from(from, np) {
         for (pp = np->properties; pp; pp = pp->next) {
             if (of_prop_cmp(pp->name, prop_name) == 0) {
                 of_node_get(np);
                 goto out;
             }
         }
     }
 out:
     of_node_put(from);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
     return np;
 }
 EXPORT_SYMBOL(of_find_node_with_property);
 
 static
 const struct of_device_id *__of_match_node(const struct of_device_id *matches,
                        const struct device_node *node)
 {
     const struct of_device_id *best_match = NULL;
     int score, best_score = 0;
 
     if (!matches)
         return NULL;
 
     for (; matches->name[0] || matches->type[0] || matches->compatible[0]; matches++) {
         score = __of_device_is_compatible(node, matches->compatible,
                           matches->type, matches->name);
         if (score > best_score) {
             best_match = matches;
             best_score = score;
         }
     }
 
     return best_match;
 }
 
 /**
  * of_match_node - Tell if a device_node has a matching of_match structure
  * @matches:    array of of device match structures to search in
  * @node:   the of device structure to match against
  *
  * Low level utility function used by device matching.
  */
 const struct of_device_id *of_match_node(const struct of_device_id *matches,
                      const struct device_node *node)
 {
     const struct of_device_id *match;
     unsigned long flags;
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     match = __of_match_node(matches, node);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
     return match;
 }
 EXPORT_SYMBOL(of_match_node);
 
 /**
  * of_find_matching_node_and_match - Find a node based on an of_device_id
  *                   match table.
  * @from:   The node to start searching from or NULL, the node
  *      you pass will not be searched, only the next one
  *      will; typically, you pass what the previous call
  *      returned. of_node_put() will be called on it
  * @matches:    array of of device match structures to search in
  * @match:  Updated to point at the matches entry which matched
  *
  * Return: A node pointer with refcount incremented, use
  * of_node_put() on it when done.
  */
 struct device_node *of_find_matching_node_and_match(struct device_node *from,
                     const struct of_device_id *matches,
                     const struct of_device_id **match)
 {
     struct device_node *np;
     const struct of_device_id *m;
     unsigned long flags;
 
     if (match)
         *match = NULL;
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     for_each_of_allnodes_from(from, np) {
         m = __of_match_node(matches, np);
         if (m && of_node_get(np)) {
             if (match)
                 *match = m;
             break;
         }
     }
     of_node_put(from);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
     return np;
 }
 EXPORT_SYMBOL(of_find_matching_node_and_match);
 
 /**
  * of_modalias_node - Lookup appropriate modalias for a device node
  * @node:   pointer to a device tree node
  * @modalias:   Pointer to buffer that modalias value will be copied into
  * @len:    Length of modalias value
  *
  * Based on the value of the compatible property, this routine will attempt
  * to choose an appropriate modalias value for a particular device tree node.
  * It does this by stripping the manufacturer prefix (as delimited by a ',')
  * from the first entry in the compatible list property.
  *
  * Return: This routine returns 0 on success, <0 on failure.
  */
 int of_modalias_node(struct device_node *node, char *modalias, int len)
 {
     const char *compatible, *p;
     int cplen;
 
     compatible = of_get_property(node, "compatible", &cplen);
     if (!compatible || strlen(compatible) > cplen)
         return -ENODEV;
     p = strchr(compatible, ',');
     strlcpy(modalias, p ? p + 1 : compatible, len);
     return 0;
 }
 EXPORT_SYMBOL_GPL(of_modalias_node);
 
 /**
  * of_find_node_by_phandle - Find a node given a phandle
  * @handle: phandle of the node to find
  *
  * Return: A node pointer with refcount incremented, use
  * of_node_put() on it when done.
  */
 struct device_node *of_find_node_by_phandle(phandle handle)
 {
     struct device_node *np = NULL;
     unsigned long flags;
     u32 handle_hash;
 
     if (!handle)
         return NULL;
 
     handle_hash = of_phandle_cache_hash(handle);
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
 
     if (phandle_cache[handle_hash] &&
         handle == phandle_cache[handle_hash]->phandle)
         np = phandle_cache[handle_hash];
 
     if (!np) {
         for_each_of_allnodes(np)
             if (np->phandle == handle &&
                 !of_node_check_flag(np, OF_DETACHED)) {
                 phandle_cache[handle_hash] = np;
                 break;
             }
     }
 
     of_node_get(np);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
     return np;
 }
 EXPORT_SYMBOL(of_find_node_by_phandle);
 
 void of_print_phandle_args(const char *msg, const struct of_phandle_args *args)
 {
     int i;
     printk("%s %pOF", msg, args->np);
     for (i = 0; i < args->args_count; i++) {
         const char delim = i ? ',' : ':';
 
         pr_cont("%c%08x", delim, args->args[i]);
     }
     pr_cont("\n");
 }
 
 int of_phandle_iterator_init(struct of_phandle_iterator *it,
         const struct device_node *np,
         const char *list_name,
         const char *cells_name,
         int cell_count)
 {
     const __be32 *list;
     int size;
 
     memset(it, 0, sizeof(*it));
 
     /*
      * one of cell_count or cells_name must be provided to determine the
      * argument length.
      */
     if (cell_count < 0 && !cells_name)
         return -EINVAL;
 
     list = of_get_property(np, list_name, &size);
     if (!list)
         return -ENOENT;
 
     it->cells_name = cells_name;
     it->cell_count = cell_count;
     it->parent = np;
     it->list_end = list + size / sizeof(*list);
     it->phandle_end = list;
     it->cur = list;
 
     return 0;
 }
 EXPORT_SYMBOL_GPL(of_phandle_iterator_init);
 
 int of_phandle_iterator_next(struct of_phandle_iterator *it)
 {
     uint32_t count = 0;
 
     if (it->node) {
         of_node_put(it->node);
         it->node = NULL;
     }
 
     if (!it->cur || it->phandle_end >= it->list_end)
         return -ENOENT;
 
     it->cur = it->phandle_end;
 
     /* If phandle is 0, then it is an empty entry with no arguments. */
     it->phandle = be32_to_cpup(it->cur++);
 
     if (it->phandle) {
 
         /*
          * Find the provider node and parse the #*-cells property to
          * determine the argument length.
          */
         it->node = of_find_node_by_phandle(it->phandle);
 
         if (it->cells_name) {
             if (!it->node) {
                 pr_err("%pOF: could not find phandle %d\n",
                        it->parent, it->phandle);
                 goto err;
             }
 
             if (of_property_read_u32(it->node, it->cells_name,
                          &count)) {
                 /*
                  * If both cell_count and cells_name is given,
                  * fall back to cell_count in absence
                  * of the cells_name property
                  */
                 if (it->cell_count >= 0) {
                     count = it->cell_count;
                 } else {
                     pr_err("%pOF: could not get %s for %pOF\n",
                            it->parent,
                            it->cells_name,
                            it->node);
                     goto err;
                 }
             }
         } else {
             count = it->cell_count;
         }
 
         /*
          * Make sure that the arguments actually fit in the remaining
          * property data length
          */
         if (it->cur + count > it->list_end) {
             if (it->cells_name)
                 pr_err("%pOF: %s = %d found %td\n",
                     it->parent, it->cells_name,
                     count, it->list_end - it->cur);
             else
                 pr_err("%pOF: phandle %s needs %d, found %td\n",
                     it->parent, of_node_full_name(it->node),
                     count, it->list_end - it->cur);
             goto err;
         }
     }
 
     it->phandle_end = it->cur + count;
     it->cur_count = count;
 
     return 0;
 
 err:
     if (it->node) {
         of_node_put(it->node);
         it->node = NULL;
     }
 
     return -EINVAL;
 }
 EXPORT_SYMBOL_GPL(of_phandle_iterator_next);
 
 int of_phandle_iterator_args(struct of_phandle_iterator *it,
                  uint32_t *args,
                  int size)
 {
     int i, count;
 
     count = it->cur_count;
 
     if (WARN_ON(size < count))
         count = size;
 
     for (i = 0; i < count; i++)
         args[i] = be32_to_cpup(it->cur++);
 
     return count;
 }
 
 int __of_parse_phandle_with_args(const struct device_node *np,
                  const char *list_name,
                  const char *cells_name,
                  int cell_count, int index,
                  struct of_phandle_args *out_args)
 {
     struct of_phandle_iterator it;
     int rc, cur_index = 0;
 
     if (index < 0)
         return -EINVAL;
 
     /* Loop over the phandles until all the requested entry is found */
     of_for_each_phandle(&it, rc, np, list_name, cells_name, cell_count) {
         /*
          * All of the error cases bail out of the loop, so at
          * this point, the parsing is successful. If the requested
          * index matches, then fill the out_args structure and return,
          * or return -ENOENT for an empty entry.
          */
         rc = -ENOENT;
         if (cur_index == index) {
             if (!it.phandle)
                 goto err;
 
             if (out_args) {
                 int c;
 
                 c = of_phandle_iterator_args(&it,
                                  out_args->args,
                                  MAX_PHANDLE_ARGS);
                 out_args->np = it.node;
                 out_args->args_count = c;
             } else {
                 of_node_put(it.node);
             }
 
             /* Found it! return success */
             return 0;
         }
 
         cur_index++;
     }
 
     /*
      * Unlock node before returning result; will be one of:
      * -ENOENT : index is for empty phandle
      * -EINVAL : parsing error on data
      */
 
  err:
     of_node_put(it.node);
     return rc;
 }
 EXPORT_SYMBOL(__of_parse_phandle_with_args);
 
 /**
  * of_parse_phandle_with_args_map() - Find a node pointed by phandle in a list and remap it
  * @np:     pointer to a device tree node containing a list
  * @list_name:  property name that contains a list
  * @stem_name:  stem of property names that specify phandles' arguments count
  * @index:  index of a phandle to parse out
  * @out_args:   optional pointer to output arguments structure (will be filled)
  *
  * This function is useful to parse lists of phandles and their arguments.
  * Returns 0 on success and fills out_args, on error returns appropriate errno
  * value. The difference between this function and of_parse_phandle_with_args()
  * is that this API remaps a phandle if the node the phandle points to has
  * a <@stem_name>-map property.
  *
  * Caller is responsible to call of_node_put() on the returned out_args->np
  * pointer.
  *
  * Example::
  *
  *  phandle1: node1 {
  *      #list-cells = <2>;
  *  };
  *
  *  phandle2: node2 {
  *      #list-cells = <1>;
  *  };
  *
  *  phandle3: node3 {
  *      #list-cells = <1>;
  *      list-map = <0 &phandle2 3>,
  *             <1 &phandle2 2>,
  *             <2 &phandle1 5 1>;
  *      list-map-mask = <0x3>;
  *  };
  *
  *  node4 {
  *      list = <&phandle1 1 2 &phandle3 0>;
  *  };
  *
  * To get a device_node of the ``node2`` node you may call this:
  * of_parse_phandle_with_args(node4, "list", "list", 1, &args);
  */
 int of_parse_phandle_with_args_map(const struct device_node *np,
                    const char *list_name,
                    const char *stem_name,
                    int index, struct of_phandle_args *out_args)
 {
     char *cells_name, *map_name = NULL, *mask_name = NULL;
     char *pass_name = NULL;
     struct device_node *cur, *new = NULL;
     const __be32 *map, *mask, *pass;
     static const __be32 dummy_mask[] = { [0 ... MAX_PHANDLE_ARGS] = ~0 };
     static const __be32 dummy_pass[] = { [0 ... MAX_PHANDLE_ARGS] = 0 };
     __be32 initial_match_array[MAX_PHANDLE_ARGS];
     const __be32 *match_array = initial_match_array;
     int i, ret, map_len, match;
     u32 list_size, new_size;
 
     if (index < 0)
         return -EINVAL;
 
     cells_name = kasprintf(GFP_KERNEL, "#%s-cells", stem_name);
     if (!cells_name)
         return -ENOMEM;
 
     ret = -ENOMEM;
     map_name = kasprintf(GFP_KERNEL, "%s-map", stem_name);
     if (!map_name)
         goto free;
 
     mask_name = kasprintf(GFP_KERNEL, "%s-map-mask", stem_name);
     if (!mask_name)
         goto free;
 
     pass_name = kasprintf(GFP_KERNEL, "%s-map-pass-thru", stem_name);
     if (!pass_name)
         goto free;
 
     ret = __of_parse_phandle_with_args(np, list_name, cells_name, -1, index,
                        out_args);
     if (ret)
         goto free;
 
     /* Get the #<list>-cells property */
     cur = out_args->np;
     ret = of_property_read_u32(cur, cells_name, &list_size);
     if (ret < 0)
         goto put;
 
     /* Precalculate the match array - this simplifies match loop */
     for (i = 0; i < list_size; i++)
         initial_match_array[i] = cpu_to_be32(out_args->args[i]);
 
     ret = -EINVAL;
     while (cur) {
         /* Get the <list>-map property */
         map = of_get_property(cur, map_name, &map_len);
         if (!map) {
             ret = 0;
             goto free;
         }
         map_len /= sizeof(u32);
 
         /* Get the <list>-map-mask property (optional) */
         mask = of_get_property(cur, mask_name, NULL);
         if (!mask)
             mask = dummy_mask;
         /* Iterate through <list>-map property */
         match = 0;
         while (map_len > (list_size + 1) && !match) {
             /* Compare specifiers */
             match = 1;
             for (i = 0; i < list_size; i++, map_len--)
                 match &= !((match_array[i] ^ *map++) & mask[i]);
 
             of_node_put(new);
             new = of_find_node_by_phandle(be32_to_cpup(map));
             map++;
             map_len--;
 
             /* Check if not found */
             if (!new)
                 goto put;
 
             if (!of_device_is_available(new))
                 match = 0;
 
             ret = of_property_read_u32(new, cells_name, &new_size);
             if (ret)
                 goto put;
 
             /* Check for malformed properties */
             if (WARN_ON(new_size > MAX_PHANDLE_ARGS))
                 goto put;
             if (map_len < new_size)
                 goto put;
 
             /* Move forward by new node's #<list>-cells amount */
             map += new_size;
             map_len -= new_size;
         }
         if (!match)
             goto put;
 
         /* Get the <list>-map-pass-thru property (optional) */
         pass = of_get_property(cur, pass_name, NULL);
         if (!pass)
             pass = dummy_pass;
 
         /*
          * Successfully parsed a <list>-map translation; copy new
          * specifier into the out_args structure, keeping the
          * bits specified in <list>-map-pass-thru.
          */
         match_array = map - new_size;
         for (i = 0; i < new_size; i++) {
             __be32 val = *(map - new_size + i);
 
             if (i < list_size) {
                 val &= ~pass[i];
                 val |= cpu_to_be32(out_args->args[i]) & pass[i];
             }
 
             out_args->args[i] = be32_to_cpu(val);
         }
         out_args->args_count = list_size = new_size;
         /* Iterate again with new provider */
         out_args->np = new;
         of_node_put(cur);
         cur = new;
     }
 put:
     of_node_put(cur);
     of_node_put(new);
 free:
     kfree(mask_name);
     kfree(map_name);
     kfree(cells_name);
     kfree(pass_name);
 
     return ret;
 }
 EXPORT_SYMBOL(of_parse_phandle_with_args_map);
 
 /**
  * of_count_phandle_with_args() - Find the number of phandles references in a property
  * @np:     pointer to a device tree node containing a list
  * @list_name:  property name that contains a list
  * @cells_name: property name that specifies phandles' arguments count
  *
  * Return: The number of phandle + argument tuples within a property. It
  * is a typical pattern to encode a list of phandle and variable
  * arguments into a single property. The number of arguments is encoded
  * by a property in the phandle-target node. For example, a gpios
  * property would contain a list of GPIO specifies consisting of a
  * phandle and 1 or more arguments. The number of arguments are
  * determined by the #gpio-cells property in the node pointed to by the
  * phandle.
  */
 int of_count_phandle_with_args(const struct device_node *np, const char *list_name,
                 const char *cells_name)
 {
     struct of_phandle_iterator it;
     int rc, cur_index = 0;
 
     /*
      * If cells_name is NULL we assume a cell count of 0. This makes
      * counting the phandles trivial as each 32bit word in the list is a
      * phandle and no arguments are to consider. So we don't iterate through
      * the list but just use the length to determine the phandle count.
      */
     if (!cells_name) {
         const __be32 *list;
         int size;
 
         list = of_get_property(np, list_name, &size);
         if (!list)
             return -ENOENT;
 
         return size / sizeof(*list);
     }
 
     rc = of_phandle_iterator_init(&it, np, list_name, cells_name, -1);
     if (rc)
         return rc;
 
     while ((rc = of_phandle_iterator_next(&it)) == 0)
         cur_index += 1;
 
     if (rc != -ENOENT)
         return rc;
 
     return cur_index;
 }
 EXPORT_SYMBOL(of_count_phandle_with_args);
 
 /**
  * __of_add_property - Add a property to a node without lock operations
  * @np:     Caller's Device Node
  * @prop:   Property to add
  */
 int __of_add_property(struct device_node *np, struct property *prop)
 {
     struct property **next;
 
     prop->next = NULL;
     next = &np->properties;
     while (*next) {
         if (strcmp(prop->name, (*next)->name) == 0)
             /* duplicate ! don't insert it */
             return -EEXIST;
 
         next = &(*next)->next;
     }
     *next = prop;
 
     return 0;
 }
 
 /**
  * of_add_property - Add a property to a node
  * @np:     Caller's Device Node
  * @prop:   Property to add
  */
 int of_add_property(struct device_node *np, struct property *prop)
 {
     unsigned long flags;
     int rc;
 
     mutex_lock(&of_mutex);
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     rc = __of_add_property(np, prop);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
 
     if (!rc)
         __of_add_property_sysfs(np, prop);
 
     mutex_unlock(&of_mutex);
 
     if (!rc)
         of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop, NULL);
 
     return rc;
 }
 EXPORT_SYMBOL_GPL(of_add_property);
 
 int __of_remove_property(struct device_node *np, struct property *prop)
 {
     struct property **next;
 
     for (next = &np->properties; *next; next = &(*next)->next) {
         if (*next == prop)
             break;
     }
     if (*next == NULL)
         return -ENODEV;
 
     /* found the node */
     *next = prop->next;
     prop->next = np->deadprops;
     np->deadprops = prop;
 
     return 0;
 }
 
 /**
  * of_remove_property - Remove a property from a node.
  * @np:     Caller's Device Node
  * @prop:   Property to remove
  *
  * Note that we don't actually remove it, since we have given out
  * who-knows-how-many pointers to the data using get-property.
  * Instead we just move the property to the "dead properties"
  * list, so it won't be found any more.
  */
 int of_remove_property(struct device_node *np, struct property *prop)
 {
     unsigned long flags;
     int rc;
 
     if (!prop)
         return -ENODEV;
 
     mutex_lock(&of_mutex);
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     rc = __of_remove_property(np, prop);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
 
     if (!rc)
         __of_remove_property_sysfs(np, prop);
 
     mutex_unlock(&of_mutex);
 
     if (!rc)
         of_property_notify(OF_RECONFIG_REMOVE_PROPERTY, np, prop, NULL);
 
     return rc;
 }
 EXPORT_SYMBOL_GPL(of_remove_property);
 
 int __of_update_property(struct device_node *np, struct property *newprop,
         struct property **oldpropp)
 {
     struct property **next, *oldprop;
 
     for (next = &np->properties; *next; next = &(*next)->next) {
         if (of_prop_cmp((*next)->name, newprop->name) == 0)
             break;
     }
     *oldpropp = oldprop = *next;
 
     if (oldprop) {
         /* replace the node */
         newprop->next = oldprop->next;
         *next = newprop;
         oldprop->next = np->deadprops;
         np->deadprops = oldprop;
     } else {
         /* new node */
         newprop->next = NULL;
         *next = newprop;
     }
 
     return 0;
 }
 
 /*
  * of_update_property - Update a property in a node, if the property does
  * not exist, add it.
  *
  * Note that we don't actually remove it, since we have given out
  * who-knows-how-many pointers to the data using get-property.
  * Instead we just move the property to the "dead properties" list,
  * and add the new property to the property list
  */
 int of_update_property(struct device_node *np, struct property *newprop)
 {
     struct property *oldprop;
     unsigned long flags;
     int rc;
 
     if (!newprop->name)
         return -EINVAL;
 
     mutex_lock(&of_mutex);
 
     raw_spin_lock_irqsave(&devtree_lock, flags);
     rc = __of_update_property(np, newprop, &oldprop);
     raw_spin_unlock_irqrestore(&devtree_lock, flags);
 
     if (!rc)
         __of_update_property_sysfs(np, newprop, oldprop);
 
     mutex_unlock(&of_mutex);
 
     if (!rc)
         of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop, oldprop);
 
     return rc;
 }
 
 static void of_alias_add(struct alias_prop *ap, struct device_node *np,
              int id, const char *stem, int stem_len)
 {
     ap->np = np;
     ap->id = id;
     strncpy(ap->stem, stem, stem_len);
     ap->stem[stem_len] = 0;
     list_add_tail(&ap->link, &aliases_lookup);
     pr_debug("adding DT alias:%s: stem=%s id=%i node=%pOF\n",
          ap->alias, ap->stem, ap->id, np);
 }
 
 /**
  * of_alias_scan - Scan all properties of the 'aliases' node
  * @dt_alloc:   An allocator that provides a virtual address to memory
  *      for storing the resulting tree
  *
  * The function scans all the properties of the 'aliases' node and populates
  * the global lookup table with the properties.  It returns the
  * number of alias properties found, or an error code in case of failure.
  */
 void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align))
 {
     struct property *pp;
 
     of_aliases = of_find_node_by_path("/aliases");
     of_chosen = of_find_node_by_path("/chosen");
     if (of_chosen == NULL)
         of_chosen = of_find_node_by_path("/chosen@0");
 
     if (of_chosen) {
         /* linux,stdout-path and /aliases/stdout are for legacy compatibility */
         const char *name = NULL;
 
         if (of_property_read_string(of_chosen, "stdout-path", &name))
             of_property_read_string(of_chosen, "linux,stdout-path",
                         &name);
         if (IS_ENABLED(CONFIG_PPC) && !name)
             of_property_read_string(of_aliases, "stdout", &name);
         if (name)
             of_stdout = of_find_node_opts_by_path(name, &of_stdout_options);
         if (of_stdout)
             of_stdout->fwnode.flags |= FWNODE_FLAG_BEST_EFFORT;
     }
 
     if (!of_aliases)
         return;
 
     for_each_property_of_node(of_aliases, pp) {
         const char *start = pp->name;
         const char *end = start + strlen(start);
         struct device_node *np;
         struct alias_prop *ap;
         int id, len;
 
         /* Skip those we do not want to proceed */
         if (!strcmp(pp->name, "name") ||
             !strcmp(pp->name, "phandle") ||
             !strcmp(pp->name, "linux,phandle"))
             continue;
 
         np = of_find_node_by_path(pp->value);
         if (!np)
             continue;
 
         /* walk the alias backwards to extract the id and work out
          * the 'stem' string */
         while (isdigit(*(end-1)) && end > start)
             end--;
         len = end - start;
 
         if (kstrtoint(end, 10, &id) < 0)
             continue;
 
         /* Allocate an alias_prop with enough space for the stem */
         ap = dt_alloc(sizeof(*ap) + len + 1, __alignof__(*ap));
         if (!ap)
             continue;
         memset(ap, 0, sizeof(*ap) + len + 1);
         ap->alias = start;
         of_alias_add(ap, np, id, start, len);
     }
 }
 
 /**
  * of_alias_get_id - Get alias id for the given device_node
  * @np:     Pointer to the given device_node
  * @stem:   Alias stem of the given device_node
  *
  * The function travels the lookup table to get the alias id for the given
  * device_node and alias stem.
  *
  * Return: The alias id if found.
  */
 int of_alias_get_id(struct device_node *np, const char *stem)
 {
     struct alias_prop *app;
     int id = -ENODEV;
 
     mutex_lock(&of_mutex);
     list_for_each_entry(app, &aliases_lookup, link) {
         if (strcmp(app->stem, stem) != 0)
             continue;
 
         if (np == app->np) {
             id = app->id;
             break;
         }
     }
     mutex_unlock(&of_mutex);
 
     return id;
 }
 EXPORT_SYMBOL_GPL(of_alias_get_id);
 
 /**
  * of_alias_get_highest_id - Get highest alias id for the given stem
  * @stem:   Alias stem to be examined
  *
  * The function travels the lookup table to get the highest alias id for the
  * given alias stem.  It returns the alias id if found.
  */
 int of_alias_get_highest_id(const char *stem)
 {
     struct alias_prop *app;
     int id = -ENODEV;
 
     mutex_lock(&of_mutex);
     list_for_each_entry(app, &aliases_lookup, link) {
         if (strcmp(app->stem, stem) != 0)
             continue;
 
         if (app->id > id)
             id = app->id;
     }
     mutex_unlock(&of_mutex);
 
     return id;
 }
 EXPORT_SYMBOL_GPL(of_alias_get_highest_id);
 
 /**
  * of_console_check() - Test and setup console for DT setup
  * @dn: Pointer to device node
  * @name: Name to use for preferred console without index. ex. "ttyS"
  * @index: Index to use for preferred console.
  *
  * Check if the given device node matches the stdout-path property in the
  * /chosen node. If it does then register it as the preferred console.
  *
  * Return: TRUE if console successfully setup. Otherwise return FALSE.
  */
 bool of_console_check(struct device_node *dn, char *name, int index)
 {
     if (!dn || dn != of_stdout || console_set_on_cmdline)
         return false;
 
     /*
      * XXX: cast `options' to char pointer to suppress complication
      * warnings: printk, UART and console drivers expect char pointer.
      */
     return !add_preferred_console(name, index, (char *)of_stdout_options);
 }
 EXPORT_SYMBOL_GPL(of_console_check);
 
 /**
  * of_find_next_cache_node - Find a node's subsidiary cache
  * @np: node of type "cpu" or "cache"
  *
  * Return: A node pointer with refcount incremented, use
  * of_node_put() on it when done.  Caller should hold a reference
  * to np.
  */
 struct device_node *of_find_next_cache_node(const struct device_node *np)
 {
     struct device_node *child, *cache_node;
 
     cache_node = of_parse_phandle(np, "l2-cache", 0);
     if (!cache_node)
         cache_node = of_parse_phandle(np, "next-level-cache", 0);
 
     if (cache_node)
         return cache_node;
 
     /* OF on pmac has nodes instead of properties named "l2-cache"
      * beneath CPU nodes.
      */
     if (IS_ENABLED(CONFIG_PPC_PMAC) && of_node_is_type(np, "cpu"))
         for_each_child_of_node(np, child)
             if (of_node_is_type(child, "cache"))
                 return child;
 
     return NULL;
 }
 
 /**
  * of_find_last_cache_level - Find the level at which the last cache is
  *      present for the given logical cpu
  *
  * @cpu: cpu number(logical index) for which the last cache level is needed
  *
  * Return: The level at which the last cache is present. It is exactly
  * same as  the total number of cache levels for the given logical cpu.
  */
 int of_find_last_cache_level(unsigned int cpu)
 {
     u32 cache_level = 0;
     struct device_node *prev = NULL, *np = of_cpu_device_node_get(cpu);
 
     while (np) {
         prev = np;
         of_node_put(np);
         np = of_find_next_cache_node(np);
     }
 
     of_property_read_u32(prev, "cache-level", &cache_level);
 
     return cache_level;
 }
 
 /**
  * of_map_id - Translate an ID through a downstream mapping.
  * @np: root complex device node.
  * @id: device ID to map.
  * @map_name: property name of the map to use.
  * @map_mask_name: optional property name of the mask to use.
  * @target: optional pointer to a target device node.
  * @id_out: optional pointer to receive the translated ID.
  *
  * Given a device ID, look up the appropriate implementation-defined
  * platform ID and/or the target device which receives transactions on that
  * ID, as per the "iommu-map" and "msi-map" bindings. Either of @target or
  * @id_out may be NULL if only the other is required. If @target points to
  * a non-NULL device node pointer, only entries targeting that node will be
  * matched; if it points to a NULL value, it will receive the device node of
  * the first matching target phandle, with a reference held.
  *
  * Return: 0 on success or a standard error code on failure.
  */
 int of_map_id(struct device_node *np, u32 id,
            const char *map_name, const char *map_mask_name,
            struct device_node **target, u32 *id_out)
 {
     u32 map_mask, masked_id;
     int map_len;
     const __be32 *map = NULL;
 
     if (!np || !map_name || (!target && !id_out))
         return -EINVAL;
 
     map = of_get_property(np, map_name, &map_len);
     if (!map) {
         if (target)
             return -ENODEV;
         /* Otherwise, no map implies no translation */
         *id_out = id;
         return 0;
     }
 
     if (!map_len || map_len % (4 * sizeof(*map))) {
         pr_err("%pOF: Error: Bad %s length: %d\n", np,
             map_name, map_len);
         return -EINVAL;
     }
 
     /* The default is to select all bits. */
     map_mask = 0xffffffff;
 
     /*
      * Can be overridden by "{iommu,msi}-map-mask" property.
      * If of_property_read_u32() fails, the default is used.
      */
     if (map_mask_name)
         of_property_read_u32(np, map_mask_name, &map_mask);
 
     masked_id = map_mask & id;
     for ( ; map_len > 0; map_len -= 4 * sizeof(*map), map += 4) {
         struct device_node *phandle_node;
         u32 id_base = be32_to_cpup(map + 0);
         u32 phandle = be32_to_cpup(map + 1);
         u32 out_base = be32_to_cpup(map + 2);
         u32 id_len = be32_to_cpup(map + 3);
 
         if (id_base & ~map_mask) {
             pr_err("%pOF: Invalid %s translation - %s-mask (0x%x) ignores id-base (0x%x)\n",
                 np, map_name, map_name,
                 map_mask, id_base);
             return -EFAULT;
         }
 
         if (masked_id < id_base || masked_id >= id_base + id_len)
             continue;
 
         phandle_node = of_find_node_by_phandle(phandle);
         if (!phandle_node)
             return -ENODEV;
 
         if (target) {
             if (*target)
                 of_node_put(phandle_node);
             else
                 *target = phandle_node;
 
             if (*target != phandle_node)
                 continue;
         }
 
         if (id_out)
             *id_out = masked_id - id_base + out_base;
 
         pr_debug("%pOF: %s, using mask %08x, id-base: %08x, out-base: %08x, length: %08x, id: %08x -> %08x\n",
             np, map_name, map_mask, id_base, out_base,
             id_len, id, masked_id - id_base + out_base);
         return 0;
     }
 
     pr_info("%pOF: no %s translation for id 0x%x on %pOF\n", np, map_name,
         id, target && *target ? *target : NULL);
 
     /* Bypasses translation */
     if (id_out)
         *id_out = id;
     return 0;
 }
 EXPORT_SYMBOL_GPL(of_map_id);

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