/*
* 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 sparc32 by David S. Miller davem@davemloft.net
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/bootmem.h>
#include <linux/module.h>
#include <asm/prom.h>
#include <asm/oplib.h>
static struct device_node *allnodes;
/* use when traversing tree through the allnext, child, sibling,
* or parent members of struct device_node.
*/
static DEFINE_RWLOCK(devtree_lock);
int of_device_is_compatible(struct device_node *device, const char *compat)
{
const char* cp;
int cplen, l;
cp = (char *) of_get_property(device, "compatible", &cplen);
if (cp == NULL)
return 0;
while (cplen > 0) {
if (strncmp(cp, compat, strlen(compat)) == 0)
return 1;
l = strlen(cp) + 1;
cp += l;
cplen -= l;
}
return 0;
}
EXPORT_SYMBOL(of_device_is_compatible);
struct device_node *of_get_parent(const struct device_node *node)
{
struct device_node *np;
if (!node)
return NULL;
np = node->parent;
return np;
}
EXPORT_SYMBOL(of_get_parent);
struct device_node *of_get_next_child(const struct device_node *node,
struct device_node *prev)
{
struct device_node *next;
next = prev ? prev->sibling : node->child;
for (; next != 0; next = next->sibling) {
break;
}
return next;
}
EXPORT_SYMBOL(of_get_next_child);
struct device_node *of_find_node_by_path(const char *path)
{
struct device_node *np = allnodes;
for (; np != 0; np = np->allnext) {
if (np->full_name != 0 && strcmp(np->full_name, path) == 0)
break;
}
return np;
}
EXPORT_SYMBOL(of_find_node_by_path);
struct device_node *of_find_node_by_phandle(phandle handle)
{
struct device_node *np;
for (np = allnodes; np != 0; np = np->allnext)
if (np->node == handle)
break;
return np;
}
EXPORT_SYMBOL(of_find_node_by_phandle);
struct device_node *of_find_node_by_name(struct device_node *from,
const char *name)
{
struct device_node *np;
np = from ? from->allnext : allnodes;
for (; np != NULL; np = np->allnext)
if (np->name != NULL && strcmp(np->name, name) == 0)
break;
return np;
}
EXPORT_SYMBOL(of_find_node_by_name);
struct device_node *of_find_node_by_type(struct device_node *from,
const char *type)
{
struct device_node *np;
np = from ? from->allnext : allnodes;
for (; np != 0; np = np->allnext)
if (np->type != 0 && strcmp(np->type, type) == 0)
break;
return np;
}
EXPORT_SYMBOL(of_find_node_by_type);
struct device_node *of_find_compatible_node(struct device_node *from,
const char *type, const char *compatible)
{
struct device_node *np;
np = from ? from->allnext : allnodes;
for (; np != 0; np = np->allnext) {
if (type != NULL
&& !(np->type != 0 && strcmp(np->type, type) == 0))
continue;
if (of_device_is_compatible(np, compatible))
break;
}
return np;
}
EXPORT_SYMBOL(of_find_compatible_node);
struct property *of_find_property(struct device_node *np, const char *name,
int *lenp)
{
struct property *pp;
for (pp = np->properties; pp != 0; pp = pp->next) {
if (strcmp(pp->name, name) == 0) {
if (lenp != 0)
*lenp = pp->length;
break;
}
}
return pp;
}
EXPORT_SYMBOL(of_find_property);
/*
* Find a property with a given name for a given node
* and return the value.
*/
void *of_get_property(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);
int of_getintprop_default(struct device_node *np, const char *name, int def)
{
struct property *prop;
int len;
prop = of_find_property(np, name, &len);
if (!prop || len != 4)
return def;
return *(int *) prop->value;
}
EXPORT_SYMBOL(of_getintprop_default);
int of_n_addr_cells(struct device_node *np)
{
int* ip;
do {
if (np->parent)
np = np->parent;
ip = of_get_property(np, "#address-cells", NULL);
if (ip != NULL)
return *ip;
} while (np->parent);
/* No #address-cells property for the root node, default to 2 */
return 2;
}
EXPORT_SYMBOL(of_n_addr_cells);
int of_n_size_cells(struct device_node *np)
{
int* ip;
do {
if (np->parent)
np = np->parent;
ip = of_get_property(np, "#size-cells", NULL);
if (ip != NULL)
return *ip;
} while (np->parent);
/* No #size-cells property for the root node, default to 1 */
return 1;
}
EXPORT_SYMBOL(of_n_size_cells);
int of_set_property(struct device_node *dp, const char *name, void *val, int len)
{
struct property **prevp;
void *new_val;
int err;
new_val = kmalloc(len, GFP_KERNEL);
if (!new_val)
return -ENOMEM;
memcpy(new_val, val, len);
err = -ENODEV;
write_lock(&devtree_lock);
prevp = &dp->properties;
while (*prevp) {
struct property *prop = *prevp;
if (!strcmp(prop->name, name)) {
void *old_val = prop->value;
int ret;
ret = prom_setprop(dp->node, name, val, len);
err = -EINVAL;
if (ret >= 0) {
prop->value = new_val;
prop->length = len;
if (OF_IS_DYNAMIC(prop))
kfree(old_val);
OF_MARK_DYNAMIC(prop);
err = 0;
}
break;
}
prevp = &(*prevp)->next;
}
write_unlock(&devtree_lock);
/* XXX Upate procfs if necessary... */
return err;
}
EXPORT_SYMBOL(of_set_property);
static unsigned int prom_early_allocated;
static void * __init prom_early_alloc(unsigned long size)
{
void *ret;
ret = __alloc_bootmem(size, SMP_CACHE_BYTES, 0UL);
if (ret != NULL)
memset(ret, 0, size);
prom_early_allocated += size;
return ret;
}
static int is_root_node(const struct device_node *dp)
{
if (!dp)
return 0;
return (dp->parent == NULL);
}
/* The following routines deal with the black magic of fully naming a
* node.
*
* Certain well known named nodes are just the simple name string.
*
* Actual devices have an address specifier appended to the base name
* string, like this "foo@addr". The "addr" can be in any number of
* formats, and the platform plus the type of the node determine the
* format and how it is constructed.
*
* For children of the ROOT node, the naming convention is fixed and
* determined by whether this is a sun4u or sun4v system.
*
* For children of other nodes, it is bus type specific. So
* we walk up the tree until we discover a "device_type" property
* we recognize and we go from there.
*/
static void __init sparc32_path_component(struct device_node *dp, char *tmp_buf)
{
struct linux_prom_registers *regs;
struct property *rprop;
rprop = of_find_property(dp, "reg", NULL);
if (!rprop)
return;
regs = rprop->value;
sprintf(tmp_buf, "%s@%x,%x",
dp->name,
regs->which_io, regs->phys_addr);
}
/* "name@slot,offset" */
static void __init sbus_path_component(struct device_node *dp, char *tmp_buf)
{
struct linux_prom_registers *regs;
struct property *prop;
prop = of_find_property(dp, "reg", NULL);
if (!prop)
return;
regs = prop->value;
sprintf(tmp_buf, "%s@%x,%x",
dp->name,
regs->which_io,
regs->phys_addr);
}
/* "name@devnum[,func]" */
static void __init pci_path_component(struct device_node *dp, char *tmp_buf)
{
struct linux_prom_pci_registers *regs;
struct property *prop;
unsigned int devfn;
prop = of_find_property(dp, "reg", NULL);
if (!prop)
return;
regs = prop->value;
devfn = (regs->phys_hi >> 8) & 0xff;
if (devfn & 0x07) {
sprintf(tmp_buf, "%s@%x,%x",
dp->name,
devfn >> 3,
devfn & 0x07);
} else {
sprintf(tmp_buf, "%s@%x",
dp->name,
devfn >> 3);
}
}
/* "name@addrhi,addrlo" */
static void __init ebus_path_component(struct device_node *dp, char *tmp_buf)
{
struct linux_prom_registers *regs;
struct property *prop;
prop = of_find_property(dp, "reg", NULL);
if (!prop)
return;
regs = prop->value;
sprintf(tmp_buf, "%s@%x,%x",
dp->name,
regs->which_io, regs->phys_addr);
}
static void __init __build_path_component(struct device_node *dp, char *tmp_buf)
{
struct device_node *parent = dp->parent;
if (parent != NULL) {
if (!strcmp(parent->type, "pci") ||
!strcmp(parent->type, "pciex"))
return pci_path_component(dp, tmp_buf);
if (!strcmp(parent->type, "sbus"))
return sbus_path_component(dp, tmp_buf);
if (!strcmp(parent->type, "ebus"))
return ebus_path_component(dp, tmp_buf);
/* "isa" is handled with platform naming */
}
/* Use platform naming convention. */
return sparc32_path_component(dp, tmp_buf);
}
static char * __init build_path_component(struct device_node *dp)
{
char tmp_buf[64], *n;
tmp_buf[0] = '\0';
__build_path_component(dp, tmp_buf);
if (tmp_buf[0] == '\0')
strcpy(tmp_buf, dp->name);
n = prom_early_alloc(strlen(tmp_buf) + 1);
strcpy(n, tmp_buf);
return n;
}
static char * __init build_full_name(struct device_node *dp)
{
int len, ourlen, plen;
char *n;
plen = strlen(dp->parent->full_name);
ourlen = strlen(dp->path_component_name);
len = ourlen + plen + 2;
n = prom_early_alloc(len);
strcpy(n, dp->parent->full_name);
if (!is_root_node(dp->parent)) {
strcpy(n + plen, "/");
plen++;
}
strcpy(n + plen, dp->path_component_name);
return n;
}
static unsigned int unique_id;
static struct property * __init build_one_prop(phandle node, char *prev, char *special_name, void *special_val, int special_len)
{
static struct property *tmp = NULL;
struct property *p;
int len;
if (tmp) {
p = tmp;
memset(p, 0, sizeof(*p) + 32);
tmp = NULL;
} else {
p = prom_early_alloc(sizeof(struct property) + 32);
p->unique_id = unique_id++;
}
p->name = (char *) (p + 1);
if (special_name) {
p->length = special_len;
p->value = prom_early_alloc(special_len);
memcpy(p->value, special_val, special_len);
} else {
if (prev == NULL) {
prom_firstprop(node, p->name);
} else {
prom_nextprop(node, prev, p->name);
}
if (strlen(p->name) == 0) {
tmp = p;
return NULL;
}
p->length = prom_getproplen(node, p->name);
if (p->length <= 0) {
p->length = 0;
} else {
p->value = prom_early_alloc(p->length + 1);
prom_getproperty(node, p->name, p->value, p->length);
((unsigned char *)p->value)[p->length] = '\0';
}
}
return p;
}
static struct property * __init build_prop_list(phandle node)
{
struct property *head, *tail;
head = tail = build_one_prop(node, NULL,
".node", &node, sizeof(node));
tail->next = build_one_prop(node, NULL, NULL, NULL, 0);
tail = tail->next;
while(tail) {
tail->next = build_one_prop(node, tail->name,
NULL, NULL, 0);
tail = tail->next;
}
return head;
}
static char * __init get_one_property(phandle node, char *name)
{
char *buf = "<NULL>";
int len;
len = prom_getproplen(node, name);
if (len > 0) {
buf = prom_early_alloc(len);
len = prom_getproperty(node, name, buf, len);
}
return buf;
}
static struct device_node * __init create_node(phandle node)
{
struct device_node *dp;
if (!node)
return NULL;
dp = prom_early_alloc(sizeof(*dp));
dp->unique_id = unique_id++;
kref_init(&dp->kref);
dp->name = get_one_property(node, "name");
dp->type = get_one_property(node, "device_type");
dp->node = node;
/* Build interrupts later... */
dp->properties = build_prop_list(node);
return dp;
}
static struct device_node * __init build_tree(struct device_node *parent, phandle node, struct device_node ***nextp)
{
struct device_node *dp;
dp = create_node(node);
if (dp) {
*(*nextp) = dp;
*nextp = &dp->allnext;
dp->parent = parent;
dp->path_component_name = build_path_component(dp);
dp->full_name = build_full_name(dp);
dp->child = build_tree(dp, prom_getchild(node), nextp);
dp->sibling = build_tree(parent, prom_getsibling(node), nextp);
}
return dp;
}
void __init prom_build_devicetree(void)
{
struct device_node **nextp;
allnodes = create_node(prom_root_node);
allnodes->path_component_name = "";
allnodes->full_name = "/";
nextp = &allnodes->allnext;
allnodes->child = build_tree(allnodes,
prom_getchild(allnodes->node),
&nextp);
printk("PROM: Built device tree with %u bytes of memory.\n",
prom_early_allocated);
}
