/*
* base.c - basic devicetree functions
*
* Copyright (c) 2012 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
*
* based on Linux devicetree support
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <common.h>
#include <of.h>
#include <of_address.h>
#include <errno.h>
#include <malloc.h>
#include <init.h>
#include <memory.h>
#include <linux/sizes.h>
#include <of_graph.h>
#include <linux/ctype.h>
#include <linux/amba/bus.h>
#include <linux/err.h>
static struct device_node *root_node;
/*
* Iterate over all nodes of a tree. As a devicetree does not
* have a dedicated list head, the start node (usually the root
* node) will not be iterated over.
*/
static inline struct device_node *of_next_node(struct device_node *node)
{
struct device_node *next;
if (!node)
return root_node;
next = list_first_entry(&node->list, struct device_node, list);
return next->parent ? next : NULL;
}
#define of_tree_for_each_node_from(node, from) \
for (node = of_next_node(from); node; node = of_next_node(node))
/**
* struct alias_prop - Alias property in 'aliases' node
* @link: List node to link the structure in aliases_lookup list
* @alias: Alias property name
* @np: Pointer to device_node that the alias stands for
* @id: Index value from end of alias name
* @stem: Alias string without the index
*
* The structure represents one alias property of 'aliases' node as
* an entry in aliases_lookup list.
*/
struct alias_prop {
struct list_head link;
const char *alias;
struct device_node *np;
int id;
char stem[0];
};
static LIST_HEAD(aliases_lookup);
static struct device_node *of_aliases;
#define OF_ROOT_NODE_SIZE_CELLS_DEFAULT 1
#define OF_ROOT_NODE_ADDR_CELLS_DEFAULT 1
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);
struct property *of_find_property(const struct device_node *np,
const char *name, int *lenp)
{
struct property *pp;
if (!np)
return NULL;
list_for_each_entry(pp, &np->properties, list)
if (of_prop_cmp(pp->name, name) == 0) {
if (lenp)
*lenp = pp->length;
return pp;
}
return NULL;
}
EXPORT_SYMBOL(of_find_property);
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, np->full_name);
}
/**
* of_alias_scan - Scan all properties of 'aliases' node
*
* The function scans all the properties of 'aliases' node and populates
* the global lookup table with the properties. It returns the
* number of alias_prop found, or error code in error case.
*/
void of_alias_scan(void)
{
struct property *pp;
struct alias_prop *app, *tmp;
list_for_each_entry_safe(app, tmp, &aliases_lookup, link)
free(app);
INIT_LIST_HEAD(&aliases_lookup);
if (!root_node)
return;
of_aliases = of_find_node_by_path("/aliases");
if (!of_aliases)
return;
list_for_each_entry(pp, &of_aliases->properties, list) {
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 (!of_prop_cmp(pp->name, "name") ||
!of_prop_cmp(pp->name, "phandle") ||
!of_prop_cmp(pp->name, "linux,phandle"))
continue;
np = of_find_node_by_path(of_property_get_value(pp));
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;
id = simple_strtol(end, NULL, 10);
if (id < 0)
continue;
/* Allocate an alias_prop with enough space for the stem */
ap = xzalloc(sizeof(*ap) + len + 1);
ap->alias = start;
of_alias_add(ap, np, id, start, len);
}
}
EXPORT_SYMBOL(of_alias_scan);
/**
* 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 alias id for the given
* device_node and alias stem. It returns the alias id if find it.
*/
int of_alias_get_id(struct device_node *np, const char *stem)
{
struct alias_prop *app;
int id = -ENODEV;
list_for_each_entry(app, &aliases_lookup, link) {
if (of_node_cmp(app->stem, stem) != 0)
continue;
if (np == app->np) {
id = app->id;
break;
}
}
return id;
}
EXPORT_SYMBOL_GPL(of_alias_get_id);
const char *of_alias_get(struct device_node *np)
{
struct alias_prop *app;
list_for_each_entry(app, &aliases_lookup, link) {
if (np == app->np)
return app->alias;
}
return NULL;
}
EXPORT_SYMBOL_GPL(of_alias_get);
/*
* of_find_node_by_alias - Find a node given an alias name
* @root: the root node of the tree. If NULL, use internal tree
* @alias: the alias name to find
*/
struct device_node *of_find_node_by_alias(struct device_node *root, const char *alias)
{
struct device_node *aliasnp;
int ret;
const char *path;
if (!root)
root = root_node;
aliasnp = of_find_node_by_path_from(root, "/aliases");
if (!aliasnp)
return NULL;
ret = of_property_read_string(aliasnp, alias, &path);
if (ret)
return NULL;
return of_find_node_by_path_from(root, path);
}
EXPORT_SYMBOL_GPL(of_find_node_by_alias);
/*
* of_find_node_by_phandle_from - Find a node given a phandle from given
* root node.
* @handle: phandle of the node to find
* @root: root node of the tree to search in. If NULL use the
* internal tree.
*/
struct device_node *of_find_node_by_phandle_from(phandle phandle,
struct device_node *root)
{
struct device_node *node;
of_tree_for_each_node_from(node, root)
if (node->phandle == phandle)
return node;
return NULL;
}
EXPORT_SYMBOL(of_find_node_by_phandle_from);
/*
* of_find_node_by_phandle - Find a node given a phandle
* @handle: phandle of the node to find
*/
struct device_node *of_find_node_by_phandle(phandle phandle)
{
return of_find_node_by_phandle_from(phandle, root_node);
}
EXPORT_SYMBOL(of_find_node_by_phandle);
/*
* of_get_tree_max_phandle - Find the maximum phandle of a tree
* @root: root node of the tree to search in. If NULL use the
* internal tree.
*/
phandle of_get_tree_max_phandle(struct device_node *root)
{
struct device_node *n;
phandle max = 0;
of_tree_for_each_node_from(n, root) {
if (n->phandle > max)
max = n->phandle;
}
return max;
}
EXPORT_SYMBOL(of_get_tree_max_phandle);
/*
* of_node_create_phandle - create a phandle for a node
* @node: The node to create a phandle in
*
* returns the new phandle or the existing phandle if the node
* already has a phandle.
*/
phandle of_node_create_phandle(struct device_node *node)
{
phandle p;
struct device_node *root;
if (node->phandle)
return node->phandle;
root = of_find_root_node(node);
p = of_get_tree_max_phandle(root) + 1;
node->phandle = p;
p = cpu_to_be32(p);
of_set_property(node, "phandle", &p, sizeof(p), 1);
return node->phandle;
}
EXPORT_SYMBOL(of_node_create_phandle);
int of_set_property_to_child_phandle(struct device_node *node, char *prop_name)
{
int ret;
phandle p;
/* Check if property exist */
if (!of_get_property(of_get_parent(node), prop_name, NULL))
return -EINVAL;
/* Create or get existing phandle of child node */
p = of_node_create_phandle(node);
p = cpu_to_be32(p);
node = of_get_parent(node);
ret = of_set_property(node, prop_name, &p, sizeof(p), 0);
return ret;
}
EXPORT_SYMBOL(of_set_property_to_child_phandle);
/*
* 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);
if (!pp)
return NULL;
return of_property_get_value(pp);
}
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
*
* Returns true if the physical identifier and the logical cpu index
* correspond to the same core/thread, false otherwise.
*/
static bool 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.
*/
static bool arch_find_n_match_cpu_physical_id(struct device_node *cpun,
int cpu, unsigned int *thread)
{
return __of_find_n_match_cpu_property(cpun, "reg", cpu, thread);
}
/**
* of_get_cpu_node - Get device node associated with the given logical CPU
*
* @cpu: CPU number(logical index) for which device node is required
* @thread: if not NULL, local thread number within the physical core is
* returned
*
* The main purpose of this function is to retrieve the device node for the
* given logical CPU index. It should be used to initialize the of_node in
* cpu device. Once of_node in cpu device is populated, all the further
* references can use that instead.
*
* CPU logical to physical index mapping is architecture specific and is built
* before booting secondary cores. This function uses arch_match_cpu_phys_id
* which can be overridden by architecture specific implementation.
*
* Returns a node pointer for the logical cpu with refcount incremented, use
* of_node_put() on it when done. Returns NULL if not found.
*/
struct device_node *of_get_cpu_node(int cpu, unsigned int *thread)
{
struct device_node *cpun;
for_each_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);
/** 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)
{
struct property *prop;
const char *cp;
int index = 0, score = 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;
}
}
return score;
}
EXPORT_SYMBOL(of_device_is_compatible);
/**
* 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.
* @name: The name string to match against
*
* Returns a pointer to the node found or NULL.
*/
struct device_node *of_find_node_by_name(struct device_node *from,
const char *name)
{
struct device_node *np;
of_tree_for_each_node_from(np, from)
if (np->name && !of_node_cmp(np->name, name))
return np;
return NULL;
}
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.
* @type: The type string to match against.
*
* Returns a pointer to the node found or NULL.
*/
struct device_node *of_find_node_by_type(struct device_node *from,
const char *type)
{
struct device_node *np;
const char *device_type;
int ret;
of_tree_for_each_node_from(np, from) {
ret = of_property_read_string(np, "device_type", &device_type);
if (!ret && !of_node_cmp(device_type, type))
return np;
}
return NULL;
}
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.
* @type: The type string to match "device_type" or NULL to ignore
* (currently always ignored in barebox)
* @compatible: The string to match to one of the tokens in the device
* "compatible" list.
*
* Returns a pointer to the node found or NULL.
*/
struct device_node *of_find_compatible_node(struct device_node *from,
const char *type, const char *compatible)
{
struct device_node *np;
of_tree_for_each_node_from(np, from)
if (of_device_is_compatible(np, compatible))
return np;
return NULL;
}
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.
* @prop_name: The name of the property to look for.
*
* Returns a pointer to the node found or NULL.
*/
struct device_node *of_find_node_with_property(struct device_node *from,
const char *prop_name)
{
struct device_node *np;
of_tree_for_each_node_from(np, from) {
struct property *pp = of_find_property(np, prop_name, NULL);
if (pp)
return np;
}
return NULL;
}
EXPORT_SYMBOL(of_find_node_with_property);
/**
* of_match_node - Tell if an 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 *best_match = NULL;
int score, best_score = 0;
if (!matches || !node)
return NULL;
for (; matches->compatible; matches++) {
score = of_device_is_compatible(node, matches->compatible);
if (score > best_score) {
best_match = matches;
best_score = score;
}
}
return best_match;
}
/**
* 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.
* @matches: array of of device match structures to search in
* @match Updated to point at the matches entry which matched
*
* Returns a pointer to the node found or NULL.
*/
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;
if (match)
*match = NULL;
of_tree_for_each_node_from(np, from) {
const struct of_device_id *m = of_match_node(matches, np);
if (m) {
if (match)
*match = m;
return np;
}
}
return NULL;
}
EXPORT_SYMBOL(of_find_matching_node_and_match);
int of_match(struct device_d *dev, struct driver_d *drv)
{
const struct of_device_id *id;
id = of_match_node(drv->of_compatible, dev->device_node);
if (!id)
return 1;
dev->of_id_entry = id;
return 0;
}
EXPORT_SYMBOL(of_match);
/**
* 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 const 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);
const void *value;
if (!prop)
return ERR_PTR(-EINVAL);
value = of_property_get_value(prop);
if (!value)
return ERR_PTR(-ENODATA);
if (len > prop->length)
return ERR_PTR(-EOVERFLOW);
return 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_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 %pOF is not a multiple of %d\n",
propname, np, elem_size);
return -EINVAL;
}
return prop->length / elem_size;
}
EXPORT_SYMBOL_GPL(of_property_count_elems_of_size);
/**
* 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_value: 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_value 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_value: 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_value 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_value: 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_value 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_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);
const void *value;
if (!prop)
return -EINVAL;
value = of_property_get_value(prop);
if (!value)
return -ENODATA;
if (strnlen(value, prop->length) >= prop->length)
return -EILSEQ;
*out_string = 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;
p = of_property_get_value(prop);
if (!p)
return -ENODATA;
end = p + prop->length;
for (i = 0; p < end; i++, p += l) {
l = strlen(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);
const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur,
u32 *pu)
{
const void *curv = cur;
const void *value;
if (!prop)
return NULL;
value = of_property_get_value(prop);
if (!cur) {
curv = value;
goto out_val;
}
curv += sizeof(*cur);
if (curv >= 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;
const void *value;
if (!prop)
return NULL;
value = of_property_get_value(prop);
if (!cur)
return value;
curv += strlen(cur) + 1;
if (curv >= value + prop->length)
return NULL;
return curv;
}
EXPORT_SYMBOL_GPL(of_prop_next_string);
/**
* of_property_write_bool - Create/Delete empty (bool) property.
*
* @np: device node from which the property is to be set.
* @propname: name of the property to be set.
*
* Search for a property in a device node and create or delete the property.
* If the property already exists and write value is false, the property is
* deleted. If write value is true and the property does not exist, it is
* created. Returns 0 on success, -ENOMEM if the property or array
* of elements cannot be created.
*/
int of_property_write_bool(struct device_node *np, const char *propname,
const bool value)
{
struct property *prop = of_find_property(np, propname, NULL);
if (!value) {
if (prop)
of_delete_property(prop);
return 0;
}
if (!prop)
prop = of_new_property(np, propname, NULL, 0);
if (!prop)
return -ENOMEM;
return 0;
}
/**
* of_property_write_u8_array - Write an array of u8 to a property. If
* the property does not exist, it will be created and appended to the given
* device node.
*
* @np: device node to which the property value is to be written.
* @propname: name of the property to be written.
* @values: pointer to array elements to write.
* @sz: number of array elements to write.
*
* Search for a property in a device node and write 8-bit value(s) to
* it. If the property does not exist, it will be created and appended to
* the device node. Returns 0 on success, -ENOMEM if the property or array
* of elements cannot be created.
*/
int of_property_write_u8_array(struct device_node *np,
const char *propname, const u8 *values,
size_t sz)
{
struct property *prop = of_find_property(np, propname, NULL);
if (prop)
of_delete_property(prop);
prop = of_new_property(np, propname, values, sizeof(*values) * sz);
if (!prop)
return -ENOMEM;
return 0;
}
/**
* of_property_write_u16_array - Write an array of u16 to a property. If
* the property does not exist, it will be created and appended to the given
* device node.
*
* @np: device node to which the property value is to be written.
* @propname: name of the property to be written.
* @values: pointer to array elements to write.
* @sz: number of array elements to write.
*
* Search for a property in a device node and write 16-bit value(s) to
* it. If the property does not exist, it will be created and appended to
* the device node. Returns 0 on success, -ENOMEM if the property or array
* of elements cannot be created.
*/
int of_property_write_u16_array(struct device_node *np,
const char *propname, const u16 *values,
size_t sz)
{
struct property *prop = of_find_property(np, propname, NULL);
__be16 *val;
if (prop)
of_delete_property(prop);
prop = of_new_property(np, propname, NULL, sizeof(*val) * sz);
if (!prop)
return -ENOMEM;
val = prop->value;
while (sz--)
*val++ = cpu_to_be16(*values++);
return 0;
}
/**
* of_property_write_u32_array - Write an array of u32 to a property. If
* the property does not exist, it will be created and appended to the given
* device node.
*
* @np: device node to which the property value is to be written.
* @propname: name of the property to be written.
* @values: pointer to array elements to write.
* @sz: number of array elements to write.
*
* Search for a property in a device node and write 32-bit value(s) to
* it. If the property does not exist, it will be created and appended to
* the device node. Returns 0 on success, -ENOMEM if the property or array
* of elements cannot be created.
*/
int of_property_write_u32_array(struct device_node *np,
const char *propname, const u32 *values,
size_t sz)
{
struct property *prop = of_find_property(np, propname, NULL);
__be32 *val;
if (prop)
of_delete_property(prop);
prop = of_new_property(np, propname, NULL, sizeof(*val) * sz);
if (!prop)
return -ENOMEM;
val = prop->value;
while (sz--)
*val++ = cpu_to_be32(*values++);
return 0;
}
/**
* of_property_write_u64_array - Write an array of u64 to a property. If
* the property does not exist, it will be created and appended to the given
* device node.
*
* @np: device node to which the property value is to be written.
* @propname: name of the property to be written.
* @values: pointer to array elements to write.
* @sz: number of array elements to write.
*
* Search for a property in a device node and write 64-bit value(s) to
* it. If the property does not exist, it will be created and appended to
* the device node. Returns 0 on success, -ENOMEM if the property or array
* of elements cannot be created.
*/
int of_property_write_u64_array(struct device_node *np,
const char *propname, const u64 *values,
size_t sz)
{
struct property *prop = of_find_property(np, propname, NULL);
__be32 *val;
if (prop)
of_delete_property(prop);
prop = of_new_property(np, propname, NULL, 2 * sizeof(*val) * sz);
if (!prop)
return -ENOMEM;
val = prop->value;
while (sz--) {
of_write_number(val, *values++, 2);
val += 2;
}
return 0;
}
/**
* of_property_write_string - Write a string to a property. If
* the property does not exist, it will be created and appended to the given
* device node.
*
* @np: device node to which the property value is to be written.
* @propname: name of the property to be written.
* @value: pointer to the string to write
*
* Search for a property in a device node and write a string to
* it. If the property does not exist, it will be created and appended to
* the device node. Returns 0 on success, -ENOMEM if the property or array
* of elements cannot be created.
*/
int of_property_write_string(struct device_node *np,
const char *propname, const char *value)
{
size_t len = strlen(value);
return of_set_property(np, propname, value, len + 1, 1);
}
/**
* of_parse_phandle_from - Resolve a phandle property to a device_node pointer from
* a given root node
* @np: Pointer to device node holding phandle property
* @root: root node of the tree to search in. If NULL use the internal tree.
* @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 found or NULL.
*/
struct device_node *of_parse_phandle_from(const struct device_node *np,
struct device_node *root,
const char *phandle_name, int index)
{
const __be32 *phandle;
int size;
phandle = of_get_property(np, phandle_name, &size);
if ((!phandle) || (size < sizeof(*phandle) * (index + 1)))
return NULL;
return of_find_node_by_phandle_from(be32_to_cpup(phandle + index),
root);
}
EXPORT_SYMBOL(of_parse_phandle_from);
/**
* 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 found or NULL.
*/
struct device_node *of_parse_phandle(const struct device_node *np,
const char *phandle_name, int index)
{
return of_parse_phandle_from(np, root_node, phandle_name, index);
}
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.
*
* 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);
*/
static 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)
{
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
*/
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 &&
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;
}
/*
* 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++);
}
/* Found it! return success */
return 0;
}
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:
return rc;
}
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,
index, out_args);
}
EXPORT_SYMBOL(of_parse_phandle_with_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,
-1, NULL);
}
EXPORT_SYMBOL(of_count_phandle_with_args);
/**
* 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 true if the root node has the given value in its
* compatible property.
*/
int of_machine_is_compatible(const char *compat)
{
if (!root_node)
return 0;
return of_device_is_compatible(root_node, compat);
}
EXPORT_SYMBOL(of_machine_is_compatible);
/**
* of_find_node_by_path_from - Find a node matching a full OF path
* relative to a given root node.
* @path: The full path to match
*
* Returns a pointer to the node found or NULL.
*/
struct device_node *of_find_node_by_path_from(struct device_node *from,
const char *path)
{
char *slash, *p, *freep;
if (!from)
from = root_node;
if (!from || !path || *path != '/')
return NULL;
path++;
freep = p = xstrdup(path);
while (1) {
if (!*p)
goto out;
slash = strchr(p, '/');
if (slash)
*slash = 0;
from = of_get_child_by_name(from, p);
if (!from)
goto out;
if (!slash)
goto out;
p = slash + 1;
}
out:
free(freep);
return from;
}
EXPORT_SYMBOL(of_find_node_by_path_from);
/**
* of_find_node_by_path - Find a node matching a full OF path
* @path: The full path to match
*
* Returns a pointer to the node found or NULL.
*/
struct device_node *of_find_node_by_path(const char *path)
{
return of_find_node_by_path_from(root_node, path);
}
EXPORT_SYMBOL(of_find_node_by_path);
/**
* of_find_node_by_path_or_alias - Find a node matching a full OF path
* or an alias
* @root: The root node. If NULL the internal tree is used
* @str: the full path or alias
*
* Returns a pointer to the node found or NULL.
*/
struct device_node *of_find_node_by_path_or_alias(struct device_node *root,
const char *str)
{
struct device_node *node;
const char *slash;
char *alias;
size_t len = 0;
if (*str == '/')
return of_find_node_by_path_from(root, str);
slash = strchr(str, '/');
if (!slash)
return of_find_node_by_alias(root, str);
len = slash - str + 1;
alias = xmalloc(len);
strlcpy(alias, str, len);
node = of_find_node_by_alias(root, alias);
if (!node)
goto out;
node = of_find_node_by_path_from(node, slash);
out:
free(alias);
return node;
}
EXPORT_SYMBOL(of_find_node_by_path_or_alias);
/**
* 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);
struct device_node *of_get_root_node(void)
{
return root_node;
}
int of_set_root_node(struct device_node *node)
{
if (node && root_node)
return -EBUSY;
root_node = node;
of_alias_scan();
return 0;
}
/**
* of_device_is_available - check if a device is available for use
*
* @device: Node to check for availability
*
* Returns 1 if the status property is absent or set to "okay" or "ok",
* 0 otherwise
*/
int of_device_is_available(const struct device_node *device)
{
const char *status;
int statlen;
status = of_get_property(device, "status", &statlen);
if (status == NULL)
return 1;
if (statlen > 0) {
if (!strcmp(status, "okay") || !strcmp(status, "ok"))
return 1;
}
return 0;
}
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 pointer to the parent node or NULL if already at root.
*/
struct device_node *of_get_parent(const struct device_node *node)
{
return (!node) ? NULL : node->parent;
}
EXPORT_SYMBOL(of_get_parent);
/**
* 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)
{
prev = list_prepare_entry(prev, &node->children, parent_list);
list_for_each_entry_continue(prev, &node->children, parent_list)
if (of_device_is_available(prev))
return prev;
return NULL;
}
EXPORT_SYMBOL(of_get_next_available_child);
/**
* of_get_next_child - Iterate a node children
* @node: parent node
* @prev: previous child of the parent node, or NULL to get first
*
* Returns a node pointer with refcount incremented.
*/
struct device_node *of_get_next_child(const struct device_node *node,
struct device_node *prev)
{
prev = list_prepare_entry(prev, &node->children, parent_list);
list_for_each_entry_continue(prev, &node->children, parent_list)
return prev;
return NULL;
}
EXPORT_SYMBOL(of_get_next_child);
/**
* of_get_child_count - Count child nodes of given parent node
* @parent: parent node
*
* Returns the number of child nodes or -EINVAL on NULL parent node.
*/
int of_get_child_count(const struct device_node *parent)
{
struct device_node *child;
int num = 0;
if (!parent)
return -EINVAL;
for_each_child_of_node(parent, child)
num++;
return num;
}
EXPORT_SYMBOL(of_get_child_count);
/**
* of_get_available_child_count - Count available child nodes of given
* parent node
* @parent: parent node
*
* Returns the number of available child nodes or -EINVAL on NULL parent
* node.
*/
int of_get_available_child_count(const struct device_node *parent)
{
struct device_node *child;
int num = 0;
if (!parent)
return -EINVAL;
for_each_child_of_node(parent, child)
if (of_device_is_available(child))
num++;
return num;
}
EXPORT_SYMBOL(of_get_available_child_count);
/**
* 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.
*
* Returns 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))
return child;
}
return NULL;
}
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
*
* Returns a node pointer if found or NULL.
*/
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))
return child;
return NULL;
}
EXPORT_SYMBOL(of_get_child_by_name);
/**
* 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(const struct device_node *np,
const char *propname, const char **out_strs,
size_t sz, int skip)
{
const 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;
}
static void __of_print_nodes(struct device_node *node, int indent, const char *prefix)
{
struct device_node *n;
struct property *p;
if (!node)
return;
if (!prefix)
prefix = "";
printf("%s%*s%s%s\n", prefix, indent * 8, "", node->name, node->name ? " {" : "{");
list_for_each_entry(p, &node->properties, list) {
printf("%s%*s%s", prefix, (indent + 1) * 8, "", p->name);
if (p->length) {
printf(" = ");
of_print_property(of_property_get_value(p), p->length);
}
printf(";\n");
}
list_for_each_entry(n, &node->children, parent_list) {
__of_print_nodes(n, indent + 1, prefix);
}
printf("%s%*s};\n", prefix, indent * 8, "");
}
void of_print_nodes(struct device_node *node, int indent)
{
__of_print_nodes(node, indent, NULL);
}
static void __of_print_property(struct property *p, int indent)
{
int i;
for (i = 0; i < indent; i++)
printf("\t");
printf("%s", p->name);
if (p->length) {
printf(" = ");
of_print_property(of_property_get_value(p), p->length);
}
printf(";\n");
}
static int __of_print_parents(struct device_node *node)
{
int indent, i;
if (!node->parent)
return 0;
indent = __of_print_parents(node->parent);
for (i = 0; i < indent; i++)
printf("\t");
printf("%s {\n", node->name);
return indent + 1;
}
static void of_print_parents(struct device_node *node, int *printed)
{
if (*printed)
return;
__of_print_parents(node);
*printed = 1;
}
static void of_print_close(struct device_node *node, int *printed)
{
int depth = 0, i, j;
if (!*printed)
return;
while ((node = node->parent))
depth++;
for (i = depth; i > 0; i--) {
for (j = 0; j + 1 < i; j++)
printf("\t");
printf("};\n");
}
}
/**
* of_diff - compare two device trees against each other
* @a: The first device tree
* @b: The second device tree
* @indent: The initial indentation level when printing
*
* This function compares two device trees against each other and prints
* a diff-like result.
*/
void of_diff(struct device_node *a, struct device_node *b, int indent)
{
struct property *ap, *bp;
struct device_node *ca, *cb;
int printed = 0;
list_for_each_entry(ap, &a->properties, list) {
bp = of_find_property(b, ap->name, NULL);
if (!bp) {
of_print_parents(a, &printed);
printf("- ");
__of_print_property(ap, indent);
continue;
}
if (ap->length != bp->length || memcmp(of_property_get_value(ap), of_property_get_value(bp), bp->length)) {
of_print_parents(a, &printed);
printf("- ");
__of_print_property(ap, indent);
printf("+ ");
__of_print_property(bp, indent);
}
}
list_for_each_entry(bp, &b->properties, list) {
ap = of_find_property(a, bp->name, NULL);
if (!ap) {
of_print_parents(a, &printed);
printf("+ ");
__of_print_property(bp, indent);
}
}
for_each_child_of_node(a, ca) {
cb = of_get_child_by_name(b, ca->name);
if (cb) {
of_diff(ca, cb, indent + 1);
} else {
of_print_parents(a, &printed);
__of_print_nodes(ca, indent, "-");
}
}
for_each_child_of_node(b, cb) {
if (!of_get_child_by_name(a, cb->name)) {
of_print_parents(a, &printed);
__of_print_nodes(cb, indent, "+");
}
}
of_print_close(a, &printed);
}
struct device_node *of_new_node(struct device_node *parent, const char *name)
{
struct device_node *node;
node = xzalloc(sizeof(*node));
node->parent = parent;
if (parent)
list_add_tail(&node->parent_list, &parent->children);
INIT_LIST_HEAD(&node->children);
INIT_LIST_HEAD(&node->properties);
if (parent) {
node->name = xstrdup(name);
node->full_name = basprintf("%s/%s",
node->parent->full_name, name);
list_add(&node->list, &parent->list);
} else {
node->name = xstrdup("");
node->full_name = xstrdup("");
INIT_LIST_HEAD(&node->list);
}
return node;
}
/**
* of_new_property - Add a new property to a node
* @node: device node to which the property is added
* @name: Name of the new property
* @data: Value of the property (can be NULL)
* @len: Length of the value
*
* This adds a new property to a device node. @data is copied and no longer needed
* after calling this function.
*
* Return: A pointer to the new property
*/
struct property *of_new_property(struct device_node *node, const char *name,
const void *data, int len)
{
struct property *prop;
prop = xzalloc(sizeof(*prop));
prop->name = xstrdup(name);
prop->length = len;
prop->value = xzalloc(len);
if (data)
memcpy(prop->value, data, len);
list_add_tail(&prop->list, &node->properties);
return prop;
}
/**
* of_new_property_const - Add a new property to a node
* @node: device node to which the property is added
* @name: Name of the new property
* @data: Value of the property (can be NULL)
* @len: Length of the value
*
* This adds a new property to a device node. @data is used directly in the
* property and must be valid until the property is deleted again or set to
* another value. Normally you shouldn't use this function, use of_new_property()
* instead.
*
* Return: A pointer to the new property
*/
struct property *of_new_property_const(struct device_node *node, const char *name,
const void *data, int len)
{
struct property *prop;
prop = xzalloc(sizeof(*prop));
prop->name = xstrdup(name);
prop->length = len;
prop->value_const = data;
list_add_tail(&prop->list, &node->properties);
return prop;
}
void of_delete_property(struct property *pp)
{
if (!pp)
return;
list_del(&pp->list);
free(pp->name);
free(pp->value);
free(pp);
}
/**
* of_set_property - create a property for a given node
* @node - the node
* @name - the name of the property
* @val - the value for the property
* @len - the length of the properties value
* @create - if true, the property is created if not existing already
*/
int of_set_property(struct device_node *np, const char *name, const void *val, int len,
int create)
{
struct property *pp = of_find_property(np, name, NULL);
if (!np)
return -ENOENT;
if (!pp && !create)
return -ENOENT;
of_delete_property(pp);
pp = of_new_property(np, name, val, len);
if (!pp)
return -ENOMEM;
return 0;
}
static int mem_bank_num;
int of_add_memory(struct device_node *node, bool dump)
{
const char *device_type;
struct resource res;
int n = 0, ret;
ret = of_property_read_string(node, "device_type", &device_type);
if (ret || of_node_cmp(device_type, "memory"))
return -ENXIO;
while (!of_address_to_resource(node, n, &res)) {
n++;
if (!resource_size(&res))
continue;
of_add_memory_bank(node, dump, mem_bank_num,
res.start, resource_size(&res));
mem_bank_num++;
}
return 0;
}
static struct device_node *of_chosen;
static const char *of_model;
const char *of_get_model(void)
{
return of_model;
}
const struct of_device_id of_default_bus_match_table[] = {
{
.compatible = "simple-bus",
}, {
.compatible = "simple-mfd",
}, {
/* sentinel */
}
};
static void of_probe_memory(void)
{
struct device_node *memory = root_node;
/* Parse all available node with "memory" device_type */
while (1) {
memory = of_find_node_by_type(memory, "memory");
if (!memory)
break;
of_add_memory(memory, false);
}
}
int of_probe(void)
{
struct device_node *firmware;
if(!root_node)
return -ENODEV;
of_chosen = of_find_node_by_path("/chosen");
of_property_read_string(root_node, "model", &of_model);
if (of_model)
barebox_set_model(of_model);
of_probe_memory();
firmware = of_find_node_by_path("/firmware");
if (firmware)
of_platform_populate(firmware, NULL, NULL);
of_clk_init(root_node, NULL);
of_platform_populate(root_node, of_default_bus_match_table, NULL);
return 0;
}
/**
* of_create_node - create a new node including its parents
* @path - the nodepath to create
*/
struct device_node *of_create_node(struct device_node *root, const char *path)
{
char *slash, *p, *freep;
struct device_node *tmp, *dn = root;
if (*path != '/')
return NULL;
path++;
p = freep = xstrdup(path);
while (1) {
if (!*p)
goto out;
slash = strchr(p, '/');
if (slash)
*slash = 0;
tmp = of_get_child_by_name(dn, p);
if (tmp)
dn = tmp;
else
dn = of_new_node(dn, p);
if (!dn)
goto out;
if (!slash)
goto out;
p = slash + 1;
}
out:
free(freep);
return dn;
}
struct device_node *of_copy_node(struct device_node *parent, const struct device_node *other)
{
struct device_node *np, *child;
struct property *pp;
np = of_new_node(parent, other->name);
list_for_each_entry(pp, &other->properties, list)
of_new_property(np, pp->name, pp->value, pp->length);
for_each_child_of_node(other, child)
of_copy_node(np, child);
return np;
}
void of_delete_node(struct device_node *node)
{
struct device_node *n, *nt;
struct property *p, *pt;
struct device_d *dev;
if (!node)
return;
list_for_each_entry_safe(p, pt, &node->properties, list)
of_delete_property(p);
list_for_each_entry_safe(n, nt, &node->children, parent_list)
of_delete_node(n);
if (node->parent) {
list_del(&node->parent_list);
list_del(&node->list);
}
dev = of_find_device_by_node(node);
if (dev)
dev->device_node = NULL;
free(node->name);
free(node->full_name);
free(node);
if (node == root_node)
of_set_root_node(NULL);
}
int of_device_is_stdout_path(struct device_d *dev)
{
struct device_node *dn;
const char *name;
const char *p;
char *q;
if (!dev->device_node)
return 0;
name = of_get_property(of_chosen, "stdout-path", NULL);
if (!name)
name = of_get_property(of_chosen, "linux,stdout-path", NULL);
if (!name)
return 0;
/* This could make use of strchrnul if it were available */
p = strchr(name, ':');
if (!p)
p = name + strlen(name);
q = xstrndup(name, p - name);
dn = of_find_node_by_path_or_alias(NULL, q);
free(q);
return dn == dev->device_node;
}
/**
* of_add_initrd - add initrd properties to the devicetree
* @root - the root node of the tree
* @start - physical start address of the initrd image
* @end - physical end address of the initrd image
*
* Add initrd properties to the devicetree, or, if end is 0,
* delete them.
*
* Note that Linux interprets end differently than barebox. For Linux end points
* to the first address after the memory occupied by the image while barebox
* lets end pointing to the last occupied byte.
*/
int of_add_initrd(struct device_node *root, resource_size_t start,
resource_size_t end)
{
struct device_node *chosen;
__be32 buf[2];
chosen = of_create_node(root, "/chosen");
if (!chosen)
return -ENOMEM;
if (end) {
of_write_number(buf, start, 2);
of_set_property(chosen, "linux,initrd-start", buf, 8, 1);
of_write_number(buf, end + 1, 2);
of_set_property(chosen, "linux,initrd-end", buf, 8, 1);
} else {
struct property *pp;
pp = of_find_property(chosen, "linux,initrd-start", NULL);
if (pp)
of_delete_property(pp);
pp = of_find_property(chosen, "linux,initrd-end", NULL);
if (pp)
of_delete_property(pp);
}
return 0;
}
/**
* of_device_enable - enable a devicenode device
* @node - the node to enable
*
* This deletes the status property of a devicenode effectively
* enabling the device.
*/
int of_device_enable(struct device_node *node)
{
struct property *pp;
pp = of_find_property(node, "status", NULL);
if (!pp)
return 0;
of_delete_property(pp);
return 0;
}
/**
* of_device_enable_path - enable a devicenode
* @path - the nodepath to enable
*
* wrapper around of_device_enable taking the nodepath as argument
*/
int of_device_enable_path(const char *path)
{
struct device_node *node;
node = of_find_node_by_path(path);
if (!node)
return -ENODEV;
return of_device_enable(node);
}
/**
* of_device_disable - disable a devicenode device
* @node - the node to disable
*
* This sets the status of a devicenode to "disabled"
*/
int of_device_disable(struct device_node *node)
{
return of_property_write_string(node, "status", "disabled");
}
/**
* of_device_disable_path - disable a devicenode
* @path - the nodepath to disable
*
* wrapper around of_device_disable taking the nodepath as argument
*/
int of_device_disable_path(const char *path)
{
struct device_node *node;
node = of_find_node_by_path(path);
if (!node)
return -ENODEV;
return of_device_disable(node);
}
/**
* of_get_reproducible_name() - get a reproducible name of a node
* @node: The node to get a name from
*
* This function constructs a reproducible name for a node. This name can be
* used to find the same node in another device tree. The name is constructed
* from different patterns which are appended to each other.
* - If a node has no "reg" property, the name of the node is used in angle
* brackets, prepended with the result of the parent node
* - If the parent node has a "ranges" property then the address in MMIO space
* is used in square brackets
* - If a node has a "reg" property, but is not translatable in MMIO space then
* the start address is used in curly brackets, prepended with the result of
* the parent node.
*
* Returns a dynamically allocated string containing the name
*/
char *of_get_reproducible_name(struct device_node *node)
{
const __be32 *reg;
u64 addr;
u64 offset;
int na;
char *str, *res;
if (!node)
return 0;
reg = of_get_property(node, "reg", NULL);
if (!reg) {
str = of_get_reproducible_name(node->parent);
res = basprintf("%s<%s>", str, node->name);
free(str);
return res;
}
if (node->parent && of_get_property(node->parent, "ranges", NULL)) {
addr = of_translate_address(node, reg);
return basprintf("[0x%llx]", addr);
}
na = of_n_addr_cells(node);
/*
* Special workaround for the of partition binding. In the old binding
* the partitions are directly under the hardware devicenode whereas in
* the new binding the partitions are in an extra subnode with
* "fixed-partitions" compatible. We skip this extra subnode from the
* reproducible name to get the same name for both bindings.
*/
if (node->parent &&
of_device_is_compatible(node->parent, "fixed-partitions")) {
node = node->parent;
}
offset = of_read_number(reg, na);
str = of_get_reproducible_name(node->parent);
res = basprintf("%s{%llx}", str, offset);
free(str);
return res;
}
struct device_node *of_find_node_by_reproducible_name(struct device_node *from,
const char *name)
{
struct device_node *np;
of_tree_for_each_node_from(np, from) {
char *rep = of_get_reproducible_name(np);
int res;
res = of_node_cmp(rep, name);
free(rep);
if (!res)
return np;
}
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);
if (!port_node)
pr_warn("%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);
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.
*/
struct device_node *of_graph_get_port_by_id(struct device_node *node, u32 id)
{
struct device_node *port;
for_each_child_of_node(node, port) {
u32 port_id = 0;
if (strncmp(port->name, "port", 4) != 0)
continue;
of_property_read_u32(port, "reg", &port_id);
if (id == port_id)
return port;
}
return NULL;
}
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");
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 (!port) {
pr_warn("%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)
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.
*/
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 = np->parent;
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.
*/
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 np->parent;
}
EXPORT_SYMBOL(of_graph_get_remote_port);
int of_graph_port_is_available(struct device_node *node)
{
struct device_node *endpoint;
int available = 0;
for_each_child_of_node(node, endpoint) {
struct device_node *remote_parent;
remote_parent = of_graph_get_remote_port_parent(endpoint);
if (!remote_parent)
continue;
if (!of_device_is_available(remote_parent))
continue;
available = 1;
}
return available;
}
EXPORT_SYMBOL(of_graph_port_is_available);
/**
* of_get_machine_compatible - get first compatible string from the root node.
*
* Returns the string or NULL.
*/
const char *of_get_machine_compatible(void)
{
struct property *prop;
const char *name, *p;
if (!root_node)
return NULL;
prop = of_find_property(root_node, "compatible", NULL);
name = of_prop_next_string(prop, NULL);
if (!name)
return NULL;
p = strchr(name, ',');
return p ? p + 1 : name;
}
EXPORT_SYMBOL(of_get_machine_compatible);
static int of_init_hostname(void)
{
const char *name;
name = of_get_machine_compatible();
barebox_set_hostname_no_overwrite(name ?: "barebox");
return 0;
}
late_initcall(of_init_hostname);
