[POWERPC] Define of_read_ulong helper

There are various places where we want to extract an unsigned long
value from a device-tree property that can be 1 or 2 cells in length.
This replaces some open-coded calculations, and one place where we
assumed without checking that properties were the length we wanted,
with a little of_read_ulong() helper.

Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 11 insertions, 1 deletions

diff --git a/include/asm-powerpc/prom.h b/include/asm-powerpc/prom.h
index c15e66a2e681..524629769336 100644
--- a/include/asm-powerpc/prom.h
+++ b/include/asm-powerpc/prom.h
@@ -197,7 +197,7 @@ extern int release_OF_resource(struct device_node* node, int index);
  */
 
 
-/* Helper to read a big number */
+/* Helper to read a big number; size is in cells (not bytes) */
 static inline u64 of_read_number(const u32 *cell, int size)
 {
         u64 r = 0;
@@ -206,6 +206,16 @@ static inline u64 of_read_number(const u32 *cell, int size)
         return r;
 }
 
+/* Like of_read_number, but we want an unsigned long result */
+#ifdef CONFIG_PPC32
+static inline unsigned long of_read_ulong(const u32 *cell, int size)
+{
+        return cell[size-1];
+}
+#else
+#define of_read_ulong(cell, size)       of_read_number(cell, size)
+#endif
+
 /* Translate an OF address block into a CPU physical address
  */
 #define OF_BAD_ADDR     ((u64)-1)