linux/drivers/of/base.c
Rob Herring 40b0f17453 of: Use scope based kfree() cleanups
Use the relatively new scope based kfree() cleanup to simplify error
handling. Doing so reduces the chances of memory leaks and simplifies
error paths by avoiding the need for goto statements.

Reviewed-by: Saravana Kannan <saravanak@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20240409-dt-cleanup-free-v2-2-5b419a4af38d@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
2024-04-15 08:40:40 -05:00

2075 lines
53 KiB
C

// 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/cleanup.h>
#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;
of_platform_register_reconfig_notifier();
/* 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_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(const 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;
}
EXPORT_SYMBOL_GPL(of_device_compatible_match);
/**
* of_machine_compatible_match - Test root of device tree against a compatible array
* @compats: NULL terminated array of compatible strings to look for in root node's compatible property.
*
* Returns true if the root node has any of the given compatible values in its
* compatible property.
*/
bool of_machine_compatible_match(const char *const *compats)
{
struct device_node *root;
int rc = 0;
root = of_find_node_by_path("/");
if (root) {
rc = of_device_compatible_match(root, compats);
of_node_put(root);
}
return rc != 0;
}
EXPORT_SYMBOL(of_machine_compatible_match);
static bool __of_device_is_status(const struct device_node *device,
const char * const*strings)
{
const char *status;
int statlen;
if (!device)
return false;
status = __of_get_property(device, "status", &statlen);
if (status == NULL)
return false;
if (statlen > 0) {
while (*strings) {
unsigned int len = strlen(*strings);
if ((*strings)[len - 1] == '-') {
if (!strncmp(status, *strings, len))
return true;
} else {
if (!strcmp(status, *strings))
return true;
}
strings++;
}
}
return false;
}
/**
* __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)
{
static const char * const ok[] = {"okay", "ok", NULL};
if (!device)
return false;
return !__of_get_property(device, "status", NULL) ||
__of_device_is_status(device, ok);
}
/**
* __of_device_is_reserved - check if a device is reserved
*
* @device: Node to check for availability, with locks already held
*
* Return: True if the status property is set to "reserved", false otherwise
*/
static bool __of_device_is_reserved(const struct device_node *device)
{
static const char * const reserved[] = {"reserved", NULL};
return __of_device_is_status(device, reserved);
}
/**
* 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)
{
static const char * const fail[] = {"fail", "fail-", NULL};
return __of_device_is_status(device, fail);
}
/**
* 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);
static struct device_node *of_get_next_status_child(const struct device_node *node,
struct device_node *prev,
bool (*checker)(const struct device_node *))
{
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 (!checker(next))
continue;
if (of_node_get(next))
break;
}
of_node_put(prev);
raw_spin_unlock_irqrestore(&devtree_lock, flags);
return next;
}
/**
* 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)
{
return of_get_next_status_child(node, prev, __of_device_is_available);
}
EXPORT_SYMBOL(of_get_next_available_child);
/**
* of_get_next_reserved_child - Find the next reserved 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_reserved_child(const struct device_node *node,
struct device_node *prev)
{
return of_get_next_status_child(node, prev, __of_device_is_reserved);
}
EXPORT_SYMBOL(of_get_next_reserved_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_alias_from_compatible - Lookup appropriate alias for a device node
* depending on compatible
* @node: pointer to a device tree node
* @alias: Pointer to buffer that alias value will be copied into
* @len: Length of alias value
*
* Based on the value of the compatible property, this routine will attempt
* to choose an appropriate alias 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.
*
* Note: The matching on just the "product" side of the compatible is a relic
* from I2C and SPI. Please do not add any new user.
*
* Return: This routine returns 0 on success, <0 on failure.
*/
int of_alias_from_compatible(const struct device_node *node, char *alias, 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, ',');
strscpy(alias, p ? p + 1 : compatible, len);
return 0;
}
EXPORT_SYMBOL_GPL(of_alias_from_compatible);
/**
* 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 __free(kfree) = kasprintf(GFP_KERNEL, "#%s-cells", stem_name);
char *map_name __free(kfree) = kasprintf(GFP_KERNEL, "%s-map", stem_name);
char *mask_name __free(kfree) = kasprintf(GFP_KERNEL, "%s-map-mask", stem_name);
char *pass_name __free(kfree) = kasprintf(GFP_KERNEL, "%s-map-pass-thru", stem_name);
struct device_node *cur, *new = NULL;
const __be32 *map, *mask, *pass;
static const __be32 dummy_mask[] = { [0 ... MAX_PHANDLE_ARGS] = cpu_to_be32(~0) };
static const __be32 dummy_pass[] = { [0 ... MAX_PHANDLE_ARGS] = cpu_to_be32(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;
if (!cells_name || !map_name || !mask_name || !pass_name)
return -ENOMEM;
ret = __of_parse_phandle_with_args(np, list_name, cells_name, -1, index,
out_args);
if (ret)
return ret;
/* 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) {
return 0;
}
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;
new = NULL;
}
put:
of_node_put(cur);
of_node_put(new);
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);
static struct property *__of_remove_property_from_list(struct property **list, struct property *prop)
{
struct property **next;
for (next = list; *next; next = &(*next)->next) {
if (*next == prop) {
*next = prop->next;
prop->next = NULL;
return prop;
}
}
return NULL;
}
/**
* __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)
{
int rc = 0;
unsigned long flags;
struct property **next;
raw_spin_lock_irqsave(&devtree_lock, flags);
__of_remove_property_from_list(&np->deadprops, prop);
prop->next = NULL;
next = &np->properties;
while (*next) {
if (strcmp(prop->name, (*next)->name) == 0) {
/* duplicate ! don't insert it */
rc = -EEXIST;
goto out_unlock;
}
next = &(*next)->next;
}
*next = prop;
out_unlock:
raw_spin_unlock_irqrestore(&devtree_lock, flags);
if (rc)
return rc;
__of_add_property_sysfs(np, 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)
{
int rc;
mutex_lock(&of_mutex);
rc = __of_add_property(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)
{
unsigned long flags;
int rc = -ENODEV;
raw_spin_lock_irqsave(&devtree_lock, flags);
if (__of_remove_property_from_list(&np->properties, prop)) {
/* Found the property, add it to deadprops list */
prop->next = np->deadprops;
np->deadprops = prop;
rc = 0;
}
raw_spin_unlock_irqrestore(&devtree_lock, flags);
if (rc)
return rc;
__of_remove_property_sysfs(np, 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)
{
int rc;
if (!prop)
return -ENODEV;
mutex_lock(&of_mutex);
rc = __of_remove_property(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;
unsigned long flags;
raw_spin_lock_irqsave(&devtree_lock, flags);
__of_remove_property_from_list(&np->deadprops, newprop);
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;
}
raw_spin_unlock_irqrestore(&devtree_lock, flags);
__of_update_property_sysfs(np, newprop, oldprop);
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;
int rc;
if (!newprop->name)
return -EINVAL;
mutex_lock(&of_mutex);
rc = __of_update_property(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;
strscpy(ap->stem, stem, stem_len + 1);
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) {
of_node_put(prev);
prev = np;
np = of_find_next_cache_node(np);
}
of_property_read_u32(prev, "cache-level", &cache_level);
of_node_put(prev);
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);