of/flattree: Make the kernel accept ePAPR style phandle information

Currently when processing flattened device trees, the kernel expects
the phandle in a property called "linux,phandle".  The ePAPR spec -
not being Linux specific - instead requires phandles to be encoded in
a property named simply "phandle".  This patch makes the kernel accept
either form when unflattening the device tree.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 18d282f..b51f797 100644 (file)
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -310,10 +310,19 @@ unsigned long __init unflatten_dt_node(unsigned long mem,
                pp = unflatten_dt_alloc(&mem, sizeof(struct property),
                                        __alignof__(struct property));
                if (allnextpp) {
-                       if (strcmp(pname, "linux,phandle") == 0) {
+                       /* We accept flattened tree phandles either in
+                        * ePAPR-style "phandle" properties, or the
+                        * legacy "linux,phandle" properties.  If both
+                        * appear and have different values, things
+                        * will get weird.  Don't do that. */
+                       if ((strcmp(pname, "phandle") == 0) ||
+                           (strcmp(pname, "linux,phandle") == 0)) {
                                if (np->phandle == 0)
                                        np->phandle = *((u32 *)*p);
                        }
+                       /* And we process the "ibm,phandle" property
+                        * used in pSeries dynamic device tree
+                        * stuff */
                        if (strcmp(pname, "ibm,phandle") == 0)
                                np->phandle = *((u32 *)*p);
                        pp->name = pname;