Release 4.12 drivers/of/resolver.c
/*
* Functions for dealing with DT resolution
*
* Copyright (C) 2012 Pantelis Antoniou <panto@antoniou-consulting.com>
* Copyright (C) 2012 Texas Instruments Inc.
*
* 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.
*/
#define pr_fmt(fmt) "OF: resolver: " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/errno.h>
#include <linux/slab.h>
/* illegal phandle value (set when unresolved) */
#define OF_PHANDLE_ILLEGAL 0xdeadbeef
/**
* Find a node with the give full name by recursively following any of
* the child node links.
*/
static struct device_node *find_node_by_full_name(struct device_node *node,
const char *full_name)
{
struct device_node *child, *found;
if (!node)
return NULL;
if (!of_node_cmp(node->full_name, full_name))
return of_node_get(node);
for_each_child_of_node(node, child) {
found = find_node_by_full_name(child, full_name);
if (found != NULL) {
of_node_put(child);
return found;
}
}
return NULL;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Pantelis Antoniou | 74 | 84.09% | 1 | 25.00% |
| Amitoj Kaur Chawla | 10 | 11.36% | 1 | 25.00% |
| Frank Rowand | 4 | 4.55% | 2 | 50.00% |
| Total | 88 | 100.00% | 4 | 100.00% |
static phandle live_tree_max_phandle(void)
{
struct device_node *node;
phandle phandle;
unsigned long flags;
raw_spin_lock_irqsave(&devtree_lock, flags);
phandle = 0;
for_each_of_allnodes(node) {
if (node->phandle != OF_PHANDLE_ILLEGAL &&
node->phandle > phandle)
phandle = node->phandle;
}
raw_spin_unlock_irqrestore(&devtree_lock, flags);
return phandle;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Pantelis Antoniou | 68 | 98.55% | 1 | 50.00% |
| Frank Rowand | 1 | 1.45% | 1 | 50.00% |
| Total | 69 | 100.00% | 2 | 100.00% |
static void adjust_overlay_phandles(struct device_node *overlay,
int phandle_delta)
{
struct device_node *child;
struct property *prop;
phandle phandle;
/* adjust node's phandle in node */
if (overlay->phandle != 0 && overlay->phandle != OF_PHANDLE_ILLEGAL)
overlay->phandle += phandle_delta;
/* copy adjusted phandle into *phandle properties */
for_each_property_of_node(overlay, prop) {
if (of_prop_cmp(prop->name, "phandle") &&
of_prop_cmp(prop->name, "linux,phandle"))
continue;
if (prop->length < 4)
continue;
phandle = be32_to_cpup(prop->value);
if (phandle == OF_PHANDLE_ILLEGAL)
continue;
*(__be32 *)prop->value = cpu_to_be32(overlay->phandle);
}
for_each_child_of_node(overlay, child)
adjust_overlay_phandles(child, phandle_delta);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Pantelis Antoniou | 120 | 90.91% | 1 | 20.00% |
| Frank Rowand | 11 | 8.33% | 3 | 60.00% |
| Rob Herring | 1 | 0.76% | 1 | 20.00% |
| Total | 132 | 100.00% | 5 | 100.00% |
static int update_usages_of_a_phandle_reference(struct device_node *overlay,
struct property *prop_fixup, phandle phandle)
{
struct device_node *refnode;
struct property *prop;
char *value, *cur, *end, *node_path, *prop_name, *s;
int offset, len;
int err = 0;
value = kmalloc(prop_fixup->length, GFP_KERNEL);
if (!value)
return -ENOMEM;
memcpy(value, prop_fixup->value, prop_fixup->length);
/* prop_fixup contains a list of tuples of path:property_name:offset */
end = value + prop_fixup->length;
for (cur = value; cur < end; cur += len + 1) {
len = strlen(cur);
node_path = cur;
s = strchr(cur, ':');
if (!s) {
err = -EINVAL;
goto err_fail;
}
*s++ = '\0';
prop_name = s;
s = strchr(s, ':');
if (!s) {
err = -EINVAL;
goto err_fail;
}
*s++ = '\0';
err = kstrtoint(s, 10, &offset);
if (err)
goto err_fail;
refnode = find_node_by_full_name(overlay, node_path);
if (!refnode)
continue;
for_each_property_of_node(refnode, prop) {
if (!of_prop_cmp(prop->name, prop_name))
break;
}
of_node_put(refnode);
if (!prop) {
err = -ENOENT;
goto err_fail;
}
*(__be32 *)(prop->value + offset) = cpu_to_be32(phandle);
}
err_fail:
kfree(value);
return err;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Pantelis Antoniou | 247 | 83.45% | 1 | 14.29% |
| Frank Rowand | 44 | 14.86% | 5 | 71.43% |
| Amitoj Kaur Chawla | 5 | 1.69% | 1 | 14.29% |
| Total | 296 | 100.00% | 7 | 100.00% |
/* compare nodes taking into account that 'name' strips out the @ part */
static int node_name_cmp(const struct device_node *dn1,
const struct device_node *dn2)
{
const char *n1 = strrchr(dn1->full_name, '/') ? : "/";
const char *n2 = strrchr(dn2->full_name, '/') ? : "/";
return of_node_cmp(n1, n2);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Pantelis Antoniou | 59 | 98.33% | 1 | 50.00% |
| Frank Rowand | 1 | 1.67% | 1 | 50.00% |
| Total | 60 | 100.00% | 2 | 100.00% |
/*
* Adjust the local phandle references by the given phandle delta.
*
* Subtree @local_fixups, which is overlay node __local_fixups__,
* mirrors the fragment node structure at the root of the overlay.
*
* For each property in the fragments that contains a phandle reference,
* @local_fixups has a property of the same name that contains a list
* of offsets of the phandle reference(s) within the respective property
* value(s). The values at these offsets will be fixed up.
*/
static int adjust_local_phandle_references(struct device_node *local_fixups,
struct device_node *overlay, int phandle_delta)
{
struct device_node *child, *overlay_child;
struct property *prop_fix, *prop;
int err, i, count;
unsigned int off;
phandle phandle;
if (!local_fixups)
return 0;
for_each_property_of_node(local_fixups, prop_fix) {
/* skip properties added automatically */
if (!of_prop_cmp(prop_fix->name, "name") ||
!of_prop_cmp(prop_fix->name, "phandle") ||
!of_prop_cmp(prop_fix->name, "linux,phandle"))
continue;
if ((prop_fix->length % 4) != 0 || prop_fix->length == 0)
return -EINVAL;
count = prop_fix->length / sizeof(__be32);
for_each_property_of_node(overlay, prop) {
if (!of_prop_cmp(prop->name, prop_fix->name))
break;
}
if (!prop)
return -EINVAL;
for (i = 0; i < count; i++) {
off = be32_to_cpu(((__be32 *)prop_fix->value)[i]);
if ((off + 4) > prop->length)
return -EINVAL;
phandle = be32_to_cpu(*(__be32 *)(prop->value + off));
phandle += phandle_delta;
*(__be32 *)(prop->value + off) = cpu_to_be32(phandle);
}
}
/*
* These nested loops recurse down two subtrees in parallel, where the
* node names in the two subtrees match.
*
* The roots of the subtrees are the overlay's __local_fixups__ node
* and the overlay's root node.
*/
for_each_child_of_node(local_fixups, child) {
for_each_child_of_node(overlay, overlay_child)
if (!node_name_cmp(child, overlay_child))
break;
if (!overlay_child)
return -EINVAL;
err = adjust_local_phandle_references(child, overlay_child,
phandle_delta);
if (err)
return err;
}
return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Pantelis Antoniou | 269 | 87.06% | 2 | 28.57% |
| Frank Rowand | 40 | 12.94% | 5 | 71.43% |
| Total | 309 | 100.00% | 7 | 100.00% |
/**
* of_resolve_phandles - Relocate and resolve overlay against live tree
*
* @overlay: Pointer to devicetree overlay to relocate and resolve
*
* Modify (relocate) values of local phandles in @overlay to a range that
* does not conflict with the live expanded devicetree. Update references
* to the local phandles in @overlay. Update (resolve) phandle references
* in @overlay that refer to the live expanded devicetree.
*
* Phandle values in the live tree are in the range of
* 1 .. live_tree_max_phandle(). The range of phandle values in the overlay
* also begin with at 1. Adjust the phandle values in the overlay to begin
* at live_tree_max_phandle() + 1. Update references to the phandles to
* the adjusted phandle values.
*
* The name of each property in the "__fixups__" node in the overlay matches
* the name of a symbol (a label) in the live tree. The values of each
* property in the "__fixups__" node is a list of the property values in the
* overlay that need to be updated to contain the phandle reference
* corresponding to that symbol in the live tree. Update the references in
* the overlay with the phandle values in the live tree.
*
* @overlay must be detached.
*
* Resolving and applying @overlay to the live expanded devicetree must be
* protected by a mechanism to ensure that multiple overlays are processed
* in a single threaded manner so that multiple overlays will not relocate
* phandles to overlapping ranges. The mechanism to enforce this is not
* yet implemented.
*
* Return: %0 on success or a negative error value on error.
*/
int of_resolve_phandles(struct device_node *overlay)
{
struct device_node *child, *local_fixups, *refnode;
struct device_node *tree_symbols, *overlay_fixups;
struct property *prop;
const char *refpath;
phandle phandle, phandle_delta;
int err;
tree_symbols = NULL;
if (!overlay) {
pr_err("null overlay\n");
err = -EINVAL;
goto out;
}
if (!of_node_check_flag(overlay, OF_DETACHED)) {
pr_err("overlay not detached\n");
err = -EINVAL;
goto out;
}
phandle_delta = live_tree_max_phandle() + 1;
adjust_overlay_phandles(overlay, phandle_delta);
for_each_child_of_node(overlay, local_fixups)
if (!of_node_cmp(local_fixups->name, "__local_fixups__"))
break;
err = adjust_local_phandle_references(local_fixups, overlay, phandle_delta);
if (err)
goto out;
overlay_fixups = NULL;
for_each_child_of_node(overlay, child) {
if (!of_node_cmp(child->name, "__fixups__"))
overlay_fixups = child;
}
if (!overlay_fixups) {
err = 0;
goto out;
}
tree_symbols = of_find_node_by_path("/__symbols__");
if (!tree_symbols) {
pr_err("no symbols in root of device tree.\n");
err = -EINVAL;
goto out;
}
for_each_property_of_node(overlay_fixups, prop) {
/* skip properties added automatically */
if (!of_prop_cmp(prop->name, "name"))
continue;
err = of_property_read_string(tree_symbols,
prop->name, &refpath);
if (err)
goto out;
refnode = of_find_node_by_path(refpath);
if (!refnode) {
err = -ENOENT;
goto out;
}
phandle = refnode->phandle;
of_node_put(refnode);
err = update_usages_of_a_phandle_reference(overlay, prop, phandle);
if (err)
break;
}
out:
if (err)
pr_err("overlay phandle fixup failed: %d\n", err);
of_node_put(tree_symbols);
return err;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Pantelis Antoniou | 220 | 66.87% | 2 | 20.00% |
| Frank Rowand | 73 | 22.19% | 6 | 60.00% |
| Michal Suchanek | 25 | 7.60% | 1 | 10.00% |
| Moritz Fischer | 11 | 3.34% | 1 | 10.00% |
| Total | 329 | 100.00% | 10 | 100.00% |
EXPORT_SYMBOL_GPL(of_resolve_phandles);
Overall Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Pantelis Antoniou | 1094 | 82.32% | 2 | 13.33% |
| Frank Rowand | 176 | 13.24% | 8 | 53.33% |
| Michal Suchanek | 25 | 1.88% | 1 | 6.67% |
| Amitoj Kaur Chawla | 15 | 1.13% | 1 | 6.67% |
| Moritz Fischer | 11 | 0.83% | 1 | 6.67% |
| Rob Herring | 8 | 0.60% | 2 | 13.33% |
| Total | 1329 | 100.00% | 15 | 100.00% |
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