diff --git a/arch/sparc/kernel/prom.c b/arch/sparc/kernel/prom.c
index 63b2b9bd778ec45b2651a00d8891b60c0ae0237d..f3f53f2e0e1e03e70fc797c4300c078f4e952842 100644
--- a/arch/sparc/kernel/prom.c
+++ b/arch/sparc/kernel/prom.c
@@ -27,6 +27,11 @@
 
 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;
@@ -185,6 +190,54 @@ int of_getintprop_default(struct device_node *np, const char *name, int def)
 }
 EXPORT_SYMBOL(of_getintprop_default);
 
+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)
diff --git a/arch/sparc64/kernel/prom.c b/arch/sparc64/kernel/prom.c
index e9d703eea806a097aaa0c57e0c1d90e36a61d4f0..c62fd3e7a0f81e265149ee3a12a2aab0d48c9ef2 100644
--- a/arch/sparc64/kernel/prom.c
+++ b/arch/sparc64/kernel/prom.c
@@ -27,6 +27,11 @@
 
 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;
@@ -185,6 +190,54 @@ int of_getintprop_default(struct device_node *np, const char *name, int def)
 }
 EXPORT_SYMBOL(of_getintprop_default);
 
+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)
diff --git a/include/asm-sparc/prom.h b/include/asm-sparc/prom.h
index c5e3d26eabd35ea43ac995128e7e507dcdb1a21d..e9b8047470fe02efe564067fb86b4620b4c86f7f 100644
--- a/include/asm-sparc/prom.h
+++ b/include/asm-sparc/prom.h
@@ -35,6 +35,7 @@ struct property {
 	int	length;
 	void	*value;
 	struct property *next;
+	unsigned long _flags;
 };
 
 struct device_node {
@@ -60,6 +61,12 @@ struct device_node {
 	void	*data;
 };
 
+/* flag descriptions */
+#define OF_DYNAMIC 1 /* node and properties were allocated via kmalloc */
+
+#define OF_IS_DYNAMIC(x) test_bit(OF_DYNAMIC, &x->_flags)
+#define OF_MARK_DYNAMIC(x) set_bit(OF_DYNAMIC, &x->_flags)
+
 static inline void set_node_proc_entry(struct device_node *dn, struct proc_dir_entry *de)
 {
 	dn->pde = de;
@@ -88,6 +95,7 @@ extern struct property *of_find_property(struct device_node *np,
 extern int of_device_is_compatible(struct device_node *device, const char *);
 extern void *of_get_property(struct device_node *node, const char *name,
 			     int *lenp);
+extern int of_set_property(struct device_node *node, const char *name, void *val, int len);
 extern int of_getintprop_default(struct device_node *np,
 				 const char *name,
 				 int def);
diff --git a/include/asm-sparc64/prom.h b/include/asm-sparc64/prom.h
index 6d1556c0c263307f0cc95995fb04ac00ab2e84cc..c8022a337380721461a9371de5514ee4d3558565 100644
--- a/include/asm-sparc64/prom.h
+++ b/include/asm-sparc64/prom.h
@@ -35,6 +35,7 @@ struct property {
 	int	length;
 	void	*value;
 	struct property *next;
+	unsigned long _flags;
 };
 
 struct device_node {
@@ -60,6 +61,12 @@ struct device_node {
 	void	*data;
 };
 
+/* flag descriptions */
+#define OF_DYNAMIC 1 /* node and properties were allocated via kmalloc */
+
+#define OF_IS_DYNAMIC(x) test_bit(OF_DYNAMIC, &x->_flags)
+#define OF_MARK_DYNAMIC(x) set_bit(OF_DYNAMIC, &x->_flags)
+
 static inline void set_node_proc_entry(struct device_node *dn, struct proc_dir_entry *de)
 {
 	dn->pde = de;
@@ -88,6 +95,7 @@ extern struct property *of_find_property(struct device_node *np,
 extern int of_device_is_compatible(struct device_node *device, const char *);
 extern void *of_get_property(struct device_node *node, const char *name,
 			     int *lenp);
+extern int of_set_property(struct device_node *node, const char *name, void *val, int len);
 extern int of_getintprop_default(struct device_node *np,
 				 const char *name,
 				 int def);