[U-Boot] [PATCH] fdt: Try to read #address-cells/size-cells from parent

[Michal Simek]

Read #address-cells and #size-cells from parent if they are not present in
current node.

Signed-off-by: Michal Simek <michal.simek at xilinx.com>
---

I have code which read information about memory for zynqmp but memory
node most of the time doesn't contain #address/size-cells which are
present in parent node.
That's why let's try to read it from parent.

Also I think that we shouldn't return 2 if property is not found because
it has side effect on 32bit systems with #address/size-cells = <1>;

---
 lib/libfdt/fdt_addresses.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/lib/libfdt/fdt_addresses.c b/lib/libfdt/fdt_addresses.c
index 76054d98e5fd..b164d0988079 100644
--- a/lib/libfdt/fdt_addresses.c
+++ b/lib/libfdt/fdt_addresses.c
@@ -19,10 +19,15 @@ int fdt_address_cells(const void *fdt, int nodeoffset)
 	const fdt32_t *ac;
 	int val;
 	int len;
+	int parent;
 
 	ac = fdt_getprop(fdt, nodeoffset, "#address-cells", &len);
-	if (!ac)
-		return 2;
+	if (!ac) {
+		parent = fdt_parent_offset(fdt, nodeoffset);
+		ac = fdt_getprop(fdt, parent, "#address-cells", &len);
+		if (!ac)
+			return 2;
+	}
 
 	if (len != sizeof(*ac))
 		return -FDT_ERR_BADNCELLS;
@@ -39,10 +44,15 @@ int fdt_size_cells(const void *fdt, int nodeoffset)
 	const fdt32_t *sc;
 	int val;
 	int len;
+	int parent;
 
 	sc = fdt_getprop(fdt, nodeoffset, "#size-cells", &len);
-	if (!sc)
-		return 2;
+	if (!sc) {
+		parent = fdt_parent_offset(fdt, nodeoffset);
+		sc = fdt_getprop(fdt, parent, "#size-cells", &len);
+		if (!sc)
+			return 2;
+	}
 
 	if (len != sizeof(*sc))
 		return -FDT_ERR_BADNCELLS;
-- 
1.9.1