--- /dev/null
+/*
+ * 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.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#include <linux/console.h>
+#include <linux/ctype.h>
+#include <linux/cpu.h>
+#include <linux/module.h>
+#include <linux/of.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;
+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);
+
+int of_n_addr_cells(struct device_node *np)
+{
+ const __be32 *ip;
+
+ do {
+ if (np->parent)
+ np = np->parent;
+ ip = of_get_property(np, "#address-cells", NULL);
+ if (ip)
+ return be32_to_cpup(ip);
+ } while (np->parent);
+ /* No #address-cells property for the root node */
+ return OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
+}
+EXPORT_SYMBOL(of_n_addr_cells);
+
+int of_n_size_cells(struct device_node *np)
+{
+ const __be32 *ip;
+
+ do {
+ if (np->parent)
+ np = np->parent;
+ ip = of_get_property(np, "#size-cells", NULL);
+ if (ip)
+ return be32_to_cpup(ip);
+ } while (np->parent);
+ /* No #size-cells property for the root node */
+ return OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
+}
+EXPORT_SYMBOL(of_n_size_cells);
+
+#ifdef CONFIG_NUMA
+int __weak of_node_to_nid(struct device_node *np)
+{
+ return numa_node_id();
+}
+#endif
+
+#ifndef CONFIG_OF_DYNAMIC
+static void of_node_release(struct kobject *kobj)
+{
+ /* Without CONFIG_OF_DYNAMIC, no nodes gets freed */
+}
+#endif /* CONFIG_OF_DYNAMIC */
+
+struct kobj_type of_node_ktype = {
+ .release = of_node_release,
+};
+
+static ssize_t of_node_property_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf,
+ loff_t offset, size_t count)
+{
+ struct property *pp = container_of(bin_attr, struct property, attr);
+ return memory_read_from_buffer(buf, count, &offset, pp->value, pp->length);
+}
+
+static const char *safe_name(struct kobject *kobj, const char *orig_name)
+{
+ const char *name = orig_name;
+ struct kernfs_node *kn;
+ int i = 0;
+
+ /* don't be a hero. After 16 tries give up */
+ while (i < 16 && (kn = sysfs_get_dirent(kobj->sd, name))) {
+ sysfs_put(kn);
+ if (name != orig_name)
+ kfree(name);
+ name = kasprintf(GFP_KERNEL, "%s#%i", orig_name, ++i);
+ }
+
+ if (name != orig_name)
+ pr_warn("device-tree: Duplicate name in %s, renamed to \"%s\"\n",
+ kobject_name(kobj), name);
+ return name;
+}
+
+int __of_add_property_sysfs(struct device_node *np, struct property *pp)
+{
+ int rc;
+
+ /* Important: Don't leak passwords */
+ bool secure = strncmp(pp->name, "security-", 9) == 0;
+
+ if (!IS_ENABLED(CONFIG_SYSFS))
+ return 0;
+
+ if (!of_kset || !of_node_is_attached(np))
+ return 0;
+
+ sysfs_bin_attr_init(&pp->attr);
+ pp->attr.attr.name = safe_name(&np->kobj, pp->name);
+ pp->attr.attr.mode = secure ? S_IRUSR : S_IRUGO;
+ pp->attr.size = secure ? 0 : pp->length;
+ pp->attr.read = of_node_property_read;
+
+ rc = sysfs_create_bin_file(&np->kobj, &pp->attr);
+ WARN(rc, "error adding attribute %s to node %s\n", pp->name, np->full_name);
+ return rc;
+}
+
+int __of_attach_node_sysfs(struct device_node *np)
+{
+ const char *name;
+ struct property *pp;
+ int rc;
+
+ if (!IS_ENABLED(CONFIG_SYSFS))
+ return 0;
+
+ if (!of_kset)
+ return 0;
+
+ np->kobj.kset = of_kset;
+ if (!np->parent) {
+ /* Nodes without parents are new top level trees */
+ rc = kobject_add(&np->kobj, NULL, "%s",
+ safe_name(&of_kset->kobj, "base"));
+ } else {
+ name = safe_name(&np->parent->kobj, kbasename(np->full_name));
+ if (!name || !name[0])
+ return -EINVAL;
+
+ rc = kobject_add(&np->kobj, &np->parent->kobj, "%s", name);
+ }
+ if (rc)
+ return rc;
+
+ for_each_property_of_node(np, pp)
+ __of_add_property_sysfs(np, pp);
+
+ return 0;
+}
+
+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("devicetree: failed to register existing nodes\n");
+ return;
+ }
+ for_each_of_allnodes(np)
+ __of_attach_node_sysfs(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
+ *
+ * Returns 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);
+
+/*
+ * 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)
+ 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;
+
+ if (__of_find_n_match_cpu_property(cpun, "reg", cpu, thread))
+ return true;
+
+ return false;
+}
+
+/**
+ * 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.
+ *
+ * Returns a node pointer for the logical cpu if found, else NULL.
+ */
+struct device_node *of_get_cpu_node(int cpu, unsigned int *thread)
+{
+ struct device_node *cpun;
+
+ for_each_node_by_type(cpun, "cpu") {
+ if (arch_find_n_match_cpu_physical_id(cpun, cpu, thread))
+ return cpun;
+ }
+ return NULL;
+}
+EXPORT_SYMBOL(of_get_cpu_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 (!device->type || of_node_cmp(type, device->type))
+ return 0;
+ score += 2;
+ }
+
+ /* Matching name is a bit better than not */
+ if (name && name[0]) {
+ if (!device->name || of_node_cmp(name, 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);
+
+/**
+ * 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.
+ *
+ * Returns 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
+ *
+ * Returns 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
+ *
+ * Returns 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_big_endian - check if a device has BE registers
+ *
+ * @device: Node to check for endianness
+ *
+ * Returns 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
+ *
+ * Returns 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.
+ *
+ * Returns 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;
+ for (; next; next = next->sibling)
+ if (of_node_get(next))
+ break;
+ 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
+ *
+ * Returns 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_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
+ *
+ * Returns 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 (child->name && (of_node_cmp(child->name, name) == 0))
+ break;
+ return child;
+}
+EXPORT_SYMBOL(of_get_child_by_name);
+
+static 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 = strrchr(child->full_name, '/');
+ if (WARN(!name, "malformed device_node %s\n", child->full_name))
+ continue;
+ name++;
+ if (strncmp(path, name, len) == 0 && (strlen(name) == len))
+ return child;
+ }
+ return NULL;
+}
+
+/**
+ * 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
+ *
+ * Returns 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);
+ while (np && *path == '/') {
+ path++; /* Increment past '/' delimiter */
+ np = __of_find_node_by_path(np, path);
+ path = strchrnul(path, '/');
+ if (separator && separator < path)
+ break;
+ }
+ 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 it
+ * @name: The name string to match against
+ *
+ * Returns 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 (np->name && (of_node_cmp(np->name, name) == 0)
+ && 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
+ *
+ * Returns 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 (np->type && (of_node_cmp(np->type, type) == 0)
+ && 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.
+ *
+ * Returns 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.
+ *
+ * Returns 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
+ *
+ * Returns 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.
+ *
+ * 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
+ *
+ * Returns 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;
+ unsigned long flags;
+
+ if (!handle)
+ return NULL;
+
+ raw_spin_lock_irqsave(&devtree_lock, flags);
+ for_each_of_allnodes(np)
+ if (np->phandle == handle)
+ break;
+ of_node_get(np);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
+ return np;
+}
+EXPORT_SYMBOL(of_find_node_by_phandle);
+
+/**
+ * of_property_count_elems_of_size - Count the number of elements in a property
+ *
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @elem_size: size of the individual element
+ *
+ * Search for a property in a device node and count the number of elements of
+ * size elem_size in it. Returns number of elements on sucess, -EINVAL if the
+ * property does not exist or its length does not match a multiple of elem_size
+ * and -ENODATA if the property does not have a value.
+ */
+int of_property_count_elems_of_size(const struct device_node *np,
+ const char *propname, int elem_size)
+{
+ struct property *prop = of_find_property(np, propname, NULL);
+
+ if (!prop)
+ return -EINVAL;
+ if (!prop->value)
+ return -ENODATA;
+
+ if (prop->length % elem_size != 0) {
+ pr_err("size of %s in node %s is not a multiple of %d\n",
+ propname, np->full_name, elem_size);
+ return -EINVAL;
+ }
+
+ return prop->length / elem_size;
+}
+EXPORT_SYMBOL_GPL(of_property_count_elems_of_size);
+
+/**
+ * of_find_property_value_of_size
+ *
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @len: requested length of property value
+ *
+ * Search for a property in a device node and valid the requested size.
+ * Returns the property value on success, -EINVAL if the property does not
+ * exist, -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ */
+static void *of_find_property_value_of_size(const struct device_node *np,
+ const char *propname, u32 len)
+{
+ struct property *prop = of_find_property(np, propname, NULL);
+
+ if (!prop)
+ return ERR_PTR(-EINVAL);
+ if (!prop->value)
+ return ERR_PTR(-ENODATA);
+ if (len > prop->length)
+ return ERR_PTR(-EOVERFLOW);
+
+ return prop->value;
+}
+
+/**
+ * of_property_read_u32_index - Find and read a u32 from a multi-value property.
+ *
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @index: index of the u32 in the list of values
+ * @out_value: pointer to return value, modified only if no error.
+ *
+ * Search for a property in a device node and read nth 32-bit value from
+ * it. Returns 0 on success, -EINVAL if the property does not exist,
+ * -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ * The out_value is modified only if a valid u32 value can be decoded.
+ */
+int of_property_read_u32_index(const struct device_node *np,
+ const char *propname,
+ u32 index, u32 *out_value)
+{
+ const u32 *val = of_find_property_value_of_size(np, propname,
+ ((index + 1) * sizeof(*out_value)));
+
+ if (IS_ERR(val))
+ return PTR_ERR(val);
+
+ *out_value = be32_to_cpup(((__be32 *)val) + index);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(of_property_read_u32_index);
+
+/**
+ * of_property_read_u8_array - Find and read an array of u8 from a property.
+ *
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @out_values: pointer to return value, modified only if return value is 0.
+ * @sz: number of array elements to read
+ *
+ * Search for a property in a device node and read 8-bit value(s) from
+ * it. Returns 0 on success, -EINVAL if the property does not exist,
+ * -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ * dts entry of array should be like:
+ * property = /bits/ 8 <0x50 0x60 0x70>;
+ *
+ * The out_values is modified only if a valid u8 value can be decoded.
+ */
+int of_property_read_u8_array(const struct device_node *np,
+ const char *propname, u8 *out_values, size_t sz)
+{
+ const u8 *val = of_find_property_value_of_size(np, propname,
+ (sz * sizeof(*out_values)));
+
+ if (IS_ERR(val))
+ return PTR_ERR(val);
+
+ while (sz--)
+ *out_values++ = *val++;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(of_property_read_u8_array);
+
+/**
+ * of_property_read_u16_array - Find and read an array of u16 from a property.
+ *
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @out_values: pointer to return value, modified only if return value is 0.
+ * @sz: number of array elements to read
+ *
+ * Search for a property in a device node and read 16-bit value(s) from
+ * it. Returns 0 on success, -EINVAL if the property does not exist,
+ * -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ * dts entry of array should be like:
+ * property = /bits/ 16 <0x5000 0x6000 0x7000>;
+ *
+ * The out_values is modified only if a valid u16 value can be decoded.
+ */
+int of_property_read_u16_array(const struct device_node *np,
+ const char *propname, u16 *out_values, size_t sz)
+{
+ const __be16 *val = of_find_property_value_of_size(np, propname,
+ (sz * sizeof(*out_values)));
+
+ if (IS_ERR(val))
+ return PTR_ERR(val);
+
+ while (sz--)
+ *out_values++ = be16_to_cpup(val++);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(of_property_read_u16_array);
+
+/**
+ * of_property_read_u32_array - Find and read an array of 32 bit integers
+ * from a property.
+ *
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @out_values: pointer to return value, modified only if return value is 0.
+ * @sz: number of array elements to read
+ *
+ * Search for a property in a device node and read 32-bit value(s) from
+ * it. Returns 0 on success, -EINVAL if the property does not exist,
+ * -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ * The out_values is modified only if a valid u32 value can be decoded.
+ */
+int of_property_read_u32_array(const struct device_node *np,
+ const char *propname, u32 *out_values,
+ size_t sz)
+{
+ const __be32 *val = of_find_property_value_of_size(np, propname,
+ (sz * sizeof(*out_values)));
+
+ if (IS_ERR(val))
+ return PTR_ERR(val);
+
+ while (sz--)
+ *out_values++ = be32_to_cpup(val++);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(of_property_read_u32_array);
+
+/**
+ * of_property_read_u64 - Find and read a 64 bit integer from a property
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @out_value: pointer to return value, modified only if return value is 0.
+ *
+ * Search for a property in a device node and read a 64-bit value from
+ * it. Returns 0 on success, -EINVAL if the property does not exist,
+ * -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ * The out_value is modified only if a valid u64 value can be decoded.
+ */
+int of_property_read_u64(const struct device_node *np, const char *propname,
+ u64 *out_value)
+{
+ const __be32 *val = of_find_property_value_of_size(np, propname,
+ sizeof(*out_value));
+
+ if (IS_ERR(val))
+ return PTR_ERR(val);
+
+ *out_value = of_read_number(val, 2);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(of_property_read_u64);
+
+/**
+ * of_property_read_u64_array - Find and read an array of 64 bit integers
+ * from a property.
+ *
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @out_values: pointer to return value, modified only if return value is 0.
+ * @sz: number of array elements to read
+ *
+ * Search for a property in a device node and read 64-bit value(s) from
+ * it. Returns 0 on success, -EINVAL if the property does not exist,
+ * -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ * The out_values is modified only if a valid u64 value can be decoded.
+ */
+int of_property_read_u64_array(const struct device_node *np,
+ const char *propname, u64 *out_values,
+ size_t sz)
+{
+ const __be32 *val = of_find_property_value_of_size(np, propname,
+ (sz * sizeof(*out_values)));
+
+ if (IS_ERR(val))
+ return PTR_ERR(val);
+
+ while (sz--) {
+ *out_values++ = of_read_number(val, 2);
+ val += 2;
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(of_property_read_u64_array);
+
+/**
+ * of_property_read_string - Find and read a string from a property
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @out_string: pointer to null terminated return string, modified only if
+ * return value is 0.
+ *
+ * Search for a property in a device tree node and retrieve a null
+ * terminated string value (pointer to data, not a copy). Returns 0 on
+ * success, -EINVAL if the property does not exist, -ENODATA if property
+ * does not have a value, and -EILSEQ if the string is not null-terminated
+ * within the length of the property data.
+ *
+ * The out_string pointer is modified only if a valid string can be decoded.
+ */
+int of_property_read_string(struct device_node *np, const char *propname,
+ const char **out_string)
+{
+ struct property *prop = of_find_property(np, propname, NULL);
+ if (!prop)
+ return -EINVAL;
+ if (!prop->value)
+ return -ENODATA;
+ if (strnlen(prop->value, prop->length) >= prop->length)
+ return -EILSEQ;
+ *out_string = prop->value;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(of_property_read_string);
+
+/**
+ * of_property_match_string() - Find string in a list and return index
+ * @np: pointer to node containing string list property
+ * @propname: string list property name
+ * @string: pointer to string to search for in string list
+ *
+ * This function searches a string list property and returns the index
+ * of a specific string value.
+ */
+int of_property_match_string(struct device_node *np, const char *propname,
+ const char *string)
+{
+ struct property *prop = of_find_property(np, propname, NULL);
+ size_t l;
+ int i;
+ const char *p, *end;
+
+ if (!prop)
+ return -EINVAL;
+ if (!prop->value)
+ return -ENODATA;
+
+ p = prop->value;
+ end = p + prop->length;
+
+ for (i = 0; p < end; i++, p += l) {
+ l = strnlen(p, end - p) + 1;
+ if (p + l > end)
+ return -EILSEQ;
+ pr_debug("comparing %s with %s\n", string, p);
+ if (strcmp(string, p) == 0)
+ return i; /* Found it; return index */
+ }
+ return -ENODATA;
+}
+EXPORT_SYMBOL_GPL(of_property_match_string);
+
+/**
+ * of_property_read_string_helper() - Utility helper for parsing string properties
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @out_strs: output array of string pointers.
+ * @sz: number of array elements to read.
+ * @skip: Number of strings to skip over at beginning of list.
+ *
+ * Don't call this function directly. It is a utility helper for the
+ * of_property_read_string*() family of functions.
+ */
+int of_property_read_string_helper(struct device_node *np, const char *propname,
+ const char **out_strs, size_t sz, int skip)
+{
+ struct property *prop = of_find_property(np, propname, NULL);
+ int l = 0, i = 0;
+ const char *p, *end;
+
+ if (!prop)
+ return -EINVAL;
+ if (!prop->value)
+ return -ENODATA;
+ p = prop->value;
+ end = p + prop->length;
+
+ for (i = 0; p < end && (!out_strs || i < skip + sz); i++, p += l) {
+ l = strnlen(p, end - p) + 1;
+ if (p + l > end)
+ return -EILSEQ;
+ if (out_strs && i >= skip)
+ *out_strs++ = p;
+ }
+ i -= skip;
+ return i <= 0 ? -ENODATA : i;
+}
+EXPORT_SYMBOL_GPL(of_property_read_string_helper);
+
+void of_print_phandle_args(const char *msg, const struct of_phandle_args *args)
+{
+ int i;
+ printk("%s %s", msg, of_node_full_name(args->np));
+ for (i = 0; i < args->args_count; i++)
+ printk(i ? ",%08x" : ":%08x", args->args[i]);
+ printk("\n");
+}
+
+static 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)
+{
+ const __be32 *list, *list_end;
+ int rc = 0, size, cur_index = 0;
+ uint32_t count = 0;
+ struct device_node *node = NULL;
+ phandle phandle;
+
+ /* Retrieve the phandle list property */
+ list = of_get_property(np, list_name, &size);
+ if (!list)
+ return -ENOENT;
+ list_end = list + size / sizeof(*list);
+
+ /* Loop over the phandles until all the requested entry is found */
+ while (list < list_end) {
+ rc = -EINVAL;
+ count = 0;
+
+ /*
+ * If phandle is 0, then it is an empty entry with no
+ * arguments. Skip forward to the next entry.
+ */
+ phandle = be32_to_cpup(list++);
+ if (phandle) {
+ /*
+ * Find the provider node and parse the #*-cells
+ * property to determine the argument length.
+ *
+ * This is not needed if the cell count is hard-coded
+ * (i.e. cells_name not set, but cell_count is set),
+ * except when we're going to return the found node
+ * below.
+ */
+ if (cells_name || cur_index == index) {
+ node = of_find_node_by_phandle(phandle);
+ if (!node) {
+ pr_err("%s: could not find phandle\n",
+ np->full_name);
+ goto err;
+ }
+ }
+
+ if (cells_name) {
+ if (of_property_read_u32(node, cells_name,
+ &count)) {
+ pr_err("%s: could not get %s for %s\n",
+ np->full_name, cells_name,
+ node->full_name);
+ goto err;
+ }
+ } else {
+ count = cell_count;
+ }
+
+ /*
+ * Make sure that the arguments actually fit in the
+ * remaining property data length
+ */
+ if (list + count > list_end) {
+ pr_err("%s: arguments longer than property\n",
+ np->full_name);
+ goto err;
+ }
+ }
+
+ /*
+ * All of the error cases above 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 (!phandle)
+ goto err;
+
+ if (out_args) {
+ int i;
+ if (WARN_ON(count > MAX_PHANDLE_ARGS))
+ count = MAX_PHANDLE_ARGS;
+ out_args->np = node;
+ out_args->args_count = count;
+ for (i = 0; i < count; i++)
+ out_args->args[i] = be32_to_cpup(list++);
+ } else {
+ of_node_put(node);
+ }
+
+ /* Found it! return success */
+ return 0;
+ }
+
+ of_node_put(node);
+ node = NULL;
+ list += count;
+ cur_index++;
+ }
+
+ /*
+ * Unlock node before returning result; will be one of:
+ * -ENOENT : index is for empty phandle
+ * -EINVAL : parsing error on data
+ * [1..n] : Number of phandle (count mode; when index = -1)
+ */
+ rc = index < 0 ? cur_index : -ENOENT;
+ err:
+ if (node)
+ of_node_put(node);
+ return rc;
+}
+
+/**
+ * of_parse_phandle - Resolve a phandle property to a device_node pointer
+ * @np: Pointer to device node holding phandle property
+ * @phandle_name: Name of property holding a phandle value
+ * @index: For properties holding a table of phandles, this is the index into
+ * the table
+ *
+ * Returns the device_node pointer with refcount incremented. Use
+ * of_node_put() on it when done.
+ */
+struct device_node *of_parse_phandle(const struct device_node *np,
+ const char *phandle_name, int index)
+{
+ struct of_phandle_args args;
+
+ if (index < 0)
+ return NULL;
+
+ if (__of_parse_phandle_with_args(np, phandle_name, NULL, 0,
+ index, &args))
+ return NULL;
+
+ return args.np;
+}
+EXPORT_SYMBOL(of_parse_phandle);
+
+/**
+ * of_parse_phandle_with_args() - Find a node pointed by phandle in a list
+ * @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
+ * @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.
+ *
+ * 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>;
+ * }
+ *
+ * node3 {
+ * list = <&phandle1 1 2 &phandle2 3>;
+ * }
+ *
+ * To get a device_node of the `node2' node you may call this:
+ * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
+ */
+int of_parse_phandle_with_args(const struct device_node *np, const char *list_name,
+ const char *cells_name, int index,
+ struct of_phandle_args *out_args)
+{
+ if (index < 0)
+ return -EINVAL;
+ return __of_parse_phandle_with_args(np, list_name, cells_name, 0,
+ index, out_args);
+}
+EXPORT_SYMBOL(of_parse_phandle_with_args);
+
+/**
+ * of_parse_phandle_with_fixed_args() - Find a node pointed by phandle in a list
+ * @np: pointer to a device tree node containing a list
+ * @list_name: property name that contains a list
+ * @cell_count: number of argument cells following the phandle
+ * @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.
+ *
+ * Caller is responsible to call of_node_put() on the returned out_args->np
+ * pointer.
+ *
+ * Example:
+ *
+ * phandle1: node1 {
+ * }
+ *
+ * phandle2: node2 {
+ * }
+ *
+ * node3 {
+ * list = <&phandle1 0 2 &phandle2 2 3>;
+ * }
+ *
+ * To get a device_node of the `node2' node you may call this:
+ * of_parse_phandle_with_fixed_args(node3, "list", 2, 1, &args);
+ */
+int of_parse_phandle_with_fixed_args(const struct device_node *np,
+ const char *list_name, int cell_count,
+ int index, struct of_phandle_args *out_args)
+{
+ if (index < 0)
+ return -EINVAL;
+ return __of_parse_phandle_with_args(np, list_name, NULL, cell_count,
+ index, out_args);
+}
+EXPORT_SYMBOL(of_parse_phandle_with_fixed_args);
+
+/**
+ * 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
+ *
+ * Returns 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)
+{
+ return __of_parse_phandle_with_args(np, list_name, cells_name, 0, -1,
+ NULL);
+}
+EXPORT_SYMBOL(of_count_phandle_with_args);
+
+/**
+ * __of_add_property - Add a property to a node without lock operations
+ */
+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
+ */
+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;
+}
+
+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;
+}
+
+void __of_remove_property_sysfs(struct device_node *np, struct property *prop)
+{
+ if (!IS_ENABLED(CONFIG_SYSFS))
+ return;
+
+ /* at early boot, bail here and defer setup to of_init() */
+ if (of_kset && of_node_is_attached(np))
+ sysfs_remove_bin_file(&np->kobj, &prop->attr);
+}
+
+/**
+ * of_remove_property - Remove a property from a node.
+ *
+ * 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;
+
+ 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;
+}
+
+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;
+}
+
+void __of_update_property_sysfs(struct device_node *np, struct property *newprop,
+ struct property *oldprop)
+{
+ if (!IS_ENABLED(CONFIG_SYSFS))
+ return;
+
+ /* At early boot, bail out and defer setup to of_init() */
+ if (!of_kset)
+ return;
+
+ if (oldprop)
+ sysfs_remove_bin_file(&np->kobj, &oldprop->attr);
+ __of_add_property_sysfs(np, newprop);
+}
+
+/*
+ * 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=%s\n",
+ ap->alias, ap->stem, ap->id, of_node_full_name(np));
+}
+
+/**
+ * of_alias_scan - Scan all properties of the 'aliases' node
+ *
+ * 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.
+ *
+ * @dt_alloc: An allocator that provides a virtual address to memory
+ * for storing the resulting tree
+ */
+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 = of_get_property(of_chosen, "stdout-path", NULL);
+ if (!name)
+ name = of_get_property(of_chosen, "linux,stdout-path", NULL);
+ if (IS_ENABLED(CONFIG_PPC) && !name)
+ name = of_get_property(of_aliases, "stdout", NULL);
+ if (name)
+ of_stdout = of_find_node_opts_by_path(name, &of_stdout_options);
+ }
+
+ 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, 4);
+ 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. It returns 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);
+
+const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur,
+ u32 *pu)
+{
+ const void *curv = cur;
+
+ if (!prop)
+ return NULL;
+
+ if (!cur) {
+ curv = prop->value;
+ goto out_val;
+ }
+
+ curv += sizeof(*cur);
+ if (curv >= prop->value + prop->length)
+ return NULL;
+
+out_val:
+ *pu = be32_to_cpup(curv);
+ return curv;
+}
+EXPORT_SYMBOL_GPL(of_prop_next_u32);
+
+const char *of_prop_next_string(struct property *prop, const char *cur)
+{
+ const void *curv = cur;
+
+ if (!prop)
+ return NULL;
+
+ if (!cur)
+ return prop->value;
+
+ curv += strlen(cur) + 1;
+ if (curv >= prop->value + prop->length)
+ return NULL;
+
+ return curv;
+}
+EXPORT_SYMBOL_GPL(of_prop_next_string);
+
+/**
+ * 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 and return
+ * TRUE. 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;
+ return !add_preferred_console(name, index,
+ kstrdup(of_stdout_options, GFP_KERNEL));
+}
+EXPORT_SYMBOL_GPL(of_console_check);
+
+/**
+ * of_find_next_cache_node - Find a node's subsidiary cache
+ * @np: node of type "cpu" or "cache"
+ *
+ * Returns 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;
+ const phandle *handle;
+
+ handle = of_get_property(np, "l2-cache", NULL);
+ if (!handle)
+ handle = of_get_property(np, "next-level-cache", NULL);
+
+ if (handle)
+ return of_find_node_by_phandle(be32_to_cpup(handle));
+
+ /* OF on pmac has nodes instead of properties named "l2-cache"
+ * beneath CPU nodes.
+ */
+ if (!strcmp(np->type, "cpu"))
+ for_each_child_of_node(np, child)
+ if (!strcmp(child->type, "cache"))
+ return child;
+
+ return NULL;
+}
+
+/**
+ * of_graph_parse_endpoint() - parse common endpoint node properties
+ * @node: pointer to endpoint device_node
+ * @endpoint: pointer to the OF endpoint data structure
+ *
+ * The caller should hold a reference to @node.
+ */
+int of_graph_parse_endpoint(const struct device_node *node,
+ struct of_endpoint *endpoint)
+{
+ struct device_node *port_node = of_get_parent(node);
+
+ WARN_ONCE(!port_node, "%s(): endpoint %s has no parent node\n",
+ __func__, node->full_name);
+
+ memset(endpoint, 0, sizeof(*endpoint));
+
+ endpoint->local_node = node;
+ /*
+ * It doesn't matter whether the two calls below succeed.
+ * If they don't then the default value 0 is used.
+ */
+ of_property_read_u32(port_node, "reg", &endpoint->port);
+ of_property_read_u32(node, "reg", &endpoint->id);
+
+ of_node_put(port_node);
+
+ return 0;
+}
+EXPORT_SYMBOL(of_graph_parse_endpoint);
+
+/**
+ * of_graph_get_port_by_id() - get the port matching a given id
+ * @parent: pointer to the parent device node
+ * @id: id of the port
+ *
+ * Return: A 'port' node pointer with refcount incremented. The caller
+ * has to use of_node_put() on it when done.
+ */
+struct device_node *of_graph_get_port_by_id(struct device_node *parent, u32 id)
+{
+ struct device_node *node, *port;
+
+ node = of_get_child_by_name(parent, "ports");
+ if (node)
+ parent = node;
+
+ for_each_child_of_node(parent, port) {
+ u32 port_id = 0;
+
+ if (of_node_cmp(port->name, "port") != 0)
+ continue;
+ of_property_read_u32(port, "reg", &port_id);
+ if (id == port_id)
+ break;
+ }
+
+ of_node_put(node);
+
+ return port;
+}
+EXPORT_SYMBOL(of_graph_get_port_by_id);
+
+/**
+ * of_graph_get_next_endpoint() - get next endpoint node
+ * @parent: pointer to the parent device node
+ * @prev: previous endpoint node, or NULL to get first
+ *
+ * Return: An 'endpoint' node pointer with refcount incremented. Refcount
+ * of the passed @prev node is decremented.
+ */
+struct device_node *of_graph_get_next_endpoint(const struct device_node *parent,
+ struct device_node *prev)
+{
+ struct device_node *endpoint;
+ struct device_node *port;
+
+ if (!parent)
+ return NULL;
+
+ /*
+ * Start by locating the port node. If no previous endpoint is specified
+ * search for the first port node, otherwise get the previous endpoint
+ * parent port node.
+ */
+ if (!prev) {
+ struct device_node *node;
+
+ node = of_get_child_by_name(parent, "ports");
+ if (node)
+ parent = node;
+
+ port = of_get_child_by_name(parent, "port");
+ of_node_put(node);
+
+ if (!port) {
+ pr_err("%s(): no port node found in %s\n",
+ __func__, parent->full_name);
+ return NULL;
+ }
+ } else {
+ port = of_get_parent(prev);
+ if (WARN_ONCE(!port, "%s(): endpoint %s has no parent node\n",
+ __func__, prev->full_name))
+ return NULL;
+ }
+
+ while (1) {
+ /*
+ * Now that we have a port node, get the next endpoint by
+ * getting the next child. If the previous endpoint is NULL this
+ * will return the first child.
+ */
+ endpoint = of_get_next_child(port, prev);
+ if (endpoint) {
+ of_node_put(port);
+ return endpoint;
+ }
+
+ /* No more endpoints under this port, try the next one. */
+ prev = NULL;
+
+ do {
+ port = of_get_next_child(parent, port);
+ if (!port)
+ return NULL;
+ } while (of_node_cmp(port->name, "port"));
+ }
+}
+EXPORT_SYMBOL(of_graph_get_next_endpoint);
+
+/**
+ * of_graph_get_remote_port_parent() - get remote port's parent node
+ * @node: pointer to a local endpoint device_node
+ *
+ * Return: Remote device node associated with remote endpoint node linked
+ * to @node. Use of_node_put() on it when done.
+ */
+struct device_node *of_graph_get_remote_port_parent(
+ const struct device_node *node)
+{
+ struct device_node *np;
+ unsigned int depth;
+
+ /* Get remote endpoint node. */
+ np = of_parse_phandle(node, "remote-endpoint", 0);
+
+ /* Walk 3 levels up only if there is 'ports' node. */
+ for (depth = 3; depth && np; depth--) {
+ np = of_get_next_parent(np);
+ if (depth == 2 && of_node_cmp(np->name, "ports"))
+ break;
+ }
+ return np;
+}
+EXPORT_SYMBOL(of_graph_get_remote_port_parent);
+
+/**
+ * of_graph_get_remote_port() - get remote port node
+ * @node: pointer to a local endpoint device_node
+ *
+ * Return: Remote port node associated with remote endpoint node linked
+ * to @node. Use of_node_put() on it when done.
+ */
+struct device_node *of_graph_get_remote_port(const struct device_node *node)
+{
+ struct device_node *np;
+
+ /* Get remote endpoint node. */
+ np = of_parse_phandle(node, "remote-endpoint", 0);
+ if (!np)
+ return NULL;
+ return of_get_next_parent(np);
+}
+EXPORT_SYMBOL(of_graph_get_remote_port);
Code Review / kvmfornfv.git / blobdiff