linux_dsm_epyc7002/drivers/of/pdt.c
Andres Salomon a74ea43df1 of/promtree: allow DT device matching by fixing 'name' brokenness (v5)
Commit e2f2a93b, "of/promtree: add package-to-path support to pdt"
changed dp->name from using the 'name' property to using
package-to-path.  This fixed /proc/device-tree creation by eliminating
conflicts between names (the 'name' property provides names like
'battery', whereas package-to-path provides names like
'/foo/bar/battery@0', which we stripped to 'battery@0').  However, it
also breaks of_device_id table matching.

The fix that we _really_ wanted was to keep dp->name based upon
the name property ('battery'), but based dp->full_name upon
package-to-path ('battery@0').  This patch does just that.

This changes all users (except SPARC) of promtree to use the full
result from package-to-path for full_name, rather than stripping the
directory out.  In practice, the strings end up being exactly the
same; this change saves time, code, and memory.

SPARC continues to use the existing build_path_component() code.

v2: combine two patches and revert of_pdt_node_name to original version
v3: use dp->phandle instead of passing around node
v4: warn/bail out for non-sparc archs if pkg2path is not set
v5: split of_pdt_build_full_name into sparc & non-sparc versions
v6: Pass NULL to pkg2path before buf gets assigned.
    Drop check for pkg2path hook on each and every node.
v7: Don't BUG() when unable to get the full_path; create a
    known-unique name instead.

Signed-off-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-03-02 13:45:19 -07:00

249 lines
5.7 KiB
C

/* pdt.c: OF PROM device tree support code.
*
* 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 by David S. Miller davem@davemloft.net
* Adapted for multiple architectures by Andres Salomon <dilinger@queued.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/module.h>
#include <linux/errno.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/of_pdt.h>
#include <asm/prom.h>
static struct of_pdt_ops *of_pdt_prom_ops __initdata;
void __initdata (*of_pdt_build_more)(struct device_node *dp,
struct device_node ***nextp);
#if defined(CONFIG_SPARC)
unsigned int of_pdt_unique_id __initdata;
#define of_pdt_incr_unique_id(p) do { \
(p)->unique_id = of_pdt_unique_id++; \
} while (0)
static char * __init of_pdt_build_full_name(struct device_node *dp)
{
int len, ourlen, plen;
char *n;
dp->path_component_name = build_path_component(dp);
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 (!of_node_is_root(dp->parent)) {
strcpy(n + plen, "/");
plen++;
}
strcpy(n + plen, dp->path_component_name);
return n;
}
#else /* CONFIG_SPARC */
static inline void of_pdt_incr_unique_id(void *p) { }
static inline void irq_trans_init(struct device_node *dp) { }
static char * __init of_pdt_build_full_name(struct device_node *dp)
{
static int failsafe_id = 0; /* for generating unique names on failure */
char *buf;
int len;
if (of_pdt_prom_ops->pkg2path(dp->phandle, NULL, 0, &len))
goto failsafe;
buf = prom_early_alloc(len + 1);
if (of_pdt_prom_ops->pkg2path(dp->phandle, buf, len, &len))
goto failsafe;
return buf;
failsafe:
buf = prom_early_alloc(strlen(dp->parent->full_name) +
strlen(dp->name) + 16);
sprintf(buf, "%s/%s@unknown%i",
of_node_is_root(dp->parent) ? "" : dp->parent->full_name,
dp->name, failsafe_id++);
pr_err("%s: pkg2path failed; assigning %s\n", __func__, buf);
return buf;
}
#endif /* !CONFIG_SPARC */
static struct property * __init of_pdt_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 err;
if (tmp) {
p = tmp;
memset(p, 0, sizeof(*p) + 32);
tmp = NULL;
} else {
p = prom_early_alloc(sizeof(struct property) + 32);
of_pdt_incr_unique_id(p);
}
p->name = (char *) (p + 1);
if (special_name) {
strcpy(p->name, special_name);
p->length = special_len;
p->value = prom_early_alloc(special_len);
memcpy(p->value, special_val, special_len);
} else {
err = of_pdt_prom_ops->nextprop(node, prev, p->name);
if (err) {
tmp = p;
return NULL;
}
p->length = of_pdt_prom_ops->getproplen(node, p->name);
if (p->length <= 0) {
p->length = 0;
} else {
int len;
p->value = prom_early_alloc(p->length + 1);
len = of_pdt_prom_ops->getproperty(node, p->name,
p->value, p->length);
if (len <= 0)
p->length = 0;
((unsigned char *)p->value)[p->length] = '\0';
}
}
return p;
}
static struct property * __init of_pdt_build_prop_list(phandle node)
{
struct property *head, *tail;
head = tail = of_pdt_build_one_prop(node, NULL,
".node", &node, sizeof(node));
tail->next = of_pdt_build_one_prop(node, NULL, NULL, NULL, 0);
tail = tail->next;
while(tail) {
tail->next = of_pdt_build_one_prop(node, tail->name,
NULL, NULL, 0);
tail = tail->next;
}
return head;
}
static char * __init of_pdt_get_one_property(phandle node, const char *name)
{
char *buf = "<NULL>";
int len;
len = of_pdt_prom_ops->getproplen(node, name);
if (len > 0) {
buf = prom_early_alloc(len);
len = of_pdt_prom_ops->getproperty(node, name, buf, len);
}
return buf;
}
static struct device_node * __init of_pdt_create_node(phandle node,
struct device_node *parent)
{
struct device_node *dp;
if (!node)
return NULL;
dp = prom_early_alloc(sizeof(*dp));
of_pdt_incr_unique_id(dp);
dp->parent = parent;
kref_init(&dp->kref);
dp->name = of_pdt_get_one_property(node, "name");
dp->type = of_pdt_get_one_property(node, "device_type");
dp->phandle = node;
dp->properties = of_pdt_build_prop_list(node);
irq_trans_init(dp);
return dp;
}
static struct device_node * __init of_pdt_build_tree(struct device_node *parent,
phandle node,
struct device_node ***nextp)
{
struct device_node *ret = NULL, *prev_sibling = NULL;
struct device_node *dp;
while (1) {
dp = of_pdt_create_node(node, parent);
if (!dp)
break;
if (prev_sibling)
prev_sibling->sibling = dp;
if (!ret)
ret = dp;
prev_sibling = dp;
*(*nextp) = dp;
*nextp = &dp->allnext;
dp->full_name = of_pdt_build_full_name(dp);
dp->child = of_pdt_build_tree(dp,
of_pdt_prom_ops->getchild(node), nextp);
if (of_pdt_build_more)
of_pdt_build_more(dp, nextp);
node = of_pdt_prom_ops->getsibling(node);
}
return ret;
}
void __init of_pdt_build_devicetree(phandle root_node, struct of_pdt_ops *ops)
{
struct device_node **nextp;
BUG_ON(!ops);
of_pdt_prom_ops = ops;
allnodes = of_pdt_create_node(root_node, NULL);
#if defined(CONFIG_SPARC)
allnodes->path_component_name = "";
#endif
allnodes->full_name = "/";
nextp = &allnodes->allnext;
allnodes->child = of_pdt_build_tree(allnodes,
of_pdt_prom_ops->getchild(allnodes->phandle), &nextp);
}