endian: add portable endian functions

The current endian API support in coreboot doesn't follow
any known API that can be shared in userland as well as coreboot
proper. To that end provide big and little endian helper functions
that can be used in code that can be shared within coreboot proper
and userland tools.

BUG=chrome-os-partner:44827
BRANCH=None
TEST=Built rambi

Change-Id: I737facab0c849cb4b95756eefbf3ffd69e558b32
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/11618
Tested-by: build bot (Jenkins)
Reviewed-by: Nico Huber <nico.h@gmx.de>

src/include/endian.h

@@ -88,4 +88,70 @@
 #define clrbits_8(addr, clear) clrsetbits_8(addr, clear, 0)
 #define setbits_8(addr, set) setbits_8(addr, 0, set)
 
+#ifndef __ROMCC__
+/*
+ * Portable (API) endian support that can be used in code that is shared
+ * with userspace (man 3 endian) tools.
+ */
+static inline uint16_t htobe16(uint16_t host_16bits)
+{
+	return cpu_to_be16(host_16bits);
+}
+
+static inline uint16_t htole16(uint16_t host_16bits)
+{
+	return cpu_to_le16(host_16bits);
+}
+
+static inline uint16_t be16toh(uint16_t big_endian_16bits)
+{
+	return be16_to_cpu(big_endian_16bits);
+}
+
+static inline uint16_t le16toh(uint16_t little_endian_16bits)
+{
+	return le16_to_cpu(little_endian_16bits);
+}
+
+static inline uint32_t htobe32(uint32_t host_32bits)
+{
+	return cpu_to_be32(host_32bits);
+}
+
+static inline uint32_t htole32(uint32_t host_32bits)
+{
+	return cpu_to_le32(host_32bits);
+}
+
+static inline uint32_t be32toh(uint32_t big_endian_32bits)
+{
+	return be32_to_cpu(big_endian_32bits);
+}
+
+static inline uint32_t le32toh(uint32_t little_endian_32bits)
+{
+	return le32_to_cpu(little_endian_32bits);
+}
+
+static inline uint64_t htobe64(uint64_t host_64bits)
+{
+	return cpu_to_be64(host_64bits);
+}
+
+static inline uint64_t htole64(uint64_t host_64bits)
+{
+	return cpu_to_le64(host_64bits);
+}
+
+static inline uint64_t be64toh(uint64_t big_endian_64bits)
+{
+	return be64_to_cpu(big_endian_64bits);
+}
+
+static inline uint64_t le64toh(uint64_t little_endian_64bits)
+{
+	return le16_to_cpu(little_endian_64bits);
+}
+#endif
+
 #endif