of/fdt: Add endianness helper function for early init code

Provide a libfdt-based equivalent for of_device_is_big_endian(), suitable
for use in the early_init_* functions.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rob Herring <robh@kernel.org>

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 34bdc4de83d0bbf0bcef009c1b242f36d0e842ab..4b15aa163b6ef6c92660d96bc95fadeee897f192 100644 (file)
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -108,6 +108,25 @@ int of_fdt_is_compatible(const void *blob,
        return 0;
 }
 
+/**
+ * of_fdt_is_big_endian - Return true if given node needs BE MMIO accesses
+ * @blob: A device tree blob
+ * @node: node to test
+ *
+ * Returns true if the node has a "big-endian" property, or if the kernel
+ * was compiled for BE *and* the node has a "native-endian" property.
+ * Returns false otherwise.
+ */
+bool of_fdt_is_big_endian(const void *blob, unsigned long node)
+{
+       if (fdt_getprop(blob, node, "big-endian", NULL))
+               return true;
+       if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) &&
+           fdt_getprop(blob, node, "native-endian", NULL))
+               return true;
+       return false;
+}
+
 /**
  * of_fdt_match - Return true if node matches a list of compatible values
  */

diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
index 0ff360d5b3b3078b1ca85d29696d02741473edd0..587ee507965d78a1b16112a0e3c0bba7856f1d3e 100644 (file)
--- a/include/linux/of_fdt.h
+++ b/include/linux/of_fdt.h
@@ -33,6 +33,8 @@ extern void *of_fdt_get_property(const void *blob,
 extern int of_fdt_is_compatible(const void *blob,
                                unsigned long node,
                                const char *compat);
+extern bool of_fdt_is_big_endian(const void *blob,
+                                unsigned long node);
 extern int of_fdt_match(const void *blob, unsigned long node,
                        const char *const *compat);
 extern void of_fdt_unflatten_tree(unsigned long *blob,