diff --git a/objects/pflash/ccan/endian/test/compile_ok-constant.c b/objects/pflash/ccan/endian/test/compile_ok-constant.c
new file mode 100644
index 0000000..93b5a03
--- /dev/null
+++ b/objects/pflash/ccan/endian/test/compile_ok-constant.c
@@ -0,0 +1,12 @@
+#include <ccan/endian/endian.h>
+
+struct foo {
+	char one[BSWAP_16(0xFF00)];
+	char two[BSWAP_32(0xFF000000)];
+	char three[BSWAP_64(0xFF00000000000000ULL)];
+};
+
+int main(void)
+{
+	return 0;
+}
diff --git a/objects/pflash/ccan/endian/test/run.c b/objects/pflash/ccan/endian/test/run.c
new file mode 100644
index 0000000..8604068
--- /dev/null
+++ b/objects/pflash/ccan/endian/test/run.c
@@ -0,0 +1,106 @@
+#include <ccan/endian/endian.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <ccan/tap/tap.h>
+
+int main(int argc, char *argv[])
+{
+	union {
+		uint64_t u64;
+		unsigned char u64_bytes[8];
+	} u64;
+	union {
+		uint32_t u32;
+		unsigned char u32_bytes[4];
+	} u32;
+	union {
+		uint16_t u16;
+		unsigned char u16_bytes[2];
+	} u16;
+
+	plan_tests(48);
+
+	/* Straight swap tests. */
+	u64.u64_bytes[0] = 0x00;
+	u64.u64_bytes[1] = 0x11;
+	u64.u64_bytes[2] = 0x22;
+	u64.u64_bytes[3] = 0x33;
+	u64.u64_bytes[4] = 0x44;
+	u64.u64_bytes[5] = 0x55;
+	u64.u64_bytes[6] = 0x66;
+	u64.u64_bytes[7] = 0x77;
+	u64.u64 = bswap_64(u64.u64);
+	ok1(u64.u64_bytes[7] == 0x00);
+	ok1(u64.u64_bytes[6] == 0x11);
+	ok1(u64.u64_bytes[5] == 0x22);
+	ok1(u64.u64_bytes[4] == 0x33);
+	ok1(u64.u64_bytes[3] == 0x44);
+	ok1(u64.u64_bytes[2] == 0x55);
+	ok1(u64.u64_bytes[1] == 0x66);
+	ok1(u64.u64_bytes[0] == 0x77);
+
+	u32.u32_bytes[0] = 0x00;
+	u32.u32_bytes[1] = 0x11;
+	u32.u32_bytes[2] = 0x22;
+	u32.u32_bytes[3] = 0x33;
+	u32.u32 = bswap_32(u32.u32);
+	ok1(u32.u32_bytes[3] == 0x00);
+	ok1(u32.u32_bytes[2] == 0x11);
+	ok1(u32.u32_bytes[1] == 0x22);
+	ok1(u32.u32_bytes[0] == 0x33);
+
+	u16.u16_bytes[0] = 0x00;
+	u16.u16_bytes[1] = 0x11;
+	u16.u16 = bswap_16(u16.u16);
+	ok1(u16.u16_bytes[1] == 0x00);
+	ok1(u16.u16_bytes[0] == 0x11);
+
+	/* Endian tests. */
+	u64.u64 = cpu_to_le64(0x0011223344556677ULL);
+	ok1(u64.u64_bytes[0] == 0x77);
+	ok1(u64.u64_bytes[1] == 0x66);
+	ok1(u64.u64_bytes[2] == 0x55);
+	ok1(u64.u64_bytes[3] == 0x44);
+	ok1(u64.u64_bytes[4] == 0x33);
+	ok1(u64.u64_bytes[5] == 0x22);
+	ok1(u64.u64_bytes[6] == 0x11);
+	ok1(u64.u64_bytes[7] == 0x00);
+	ok1(le64_to_cpu(u64.u64) == 0x0011223344556677ULL);
+
+	u64.u64 = cpu_to_be64(0x0011223344556677ULL);
+	ok1(u64.u64_bytes[7] == 0x77);
+	ok1(u64.u64_bytes[6] == 0x66);
+	ok1(u64.u64_bytes[5] == 0x55);
+	ok1(u64.u64_bytes[4] == 0x44);
+	ok1(u64.u64_bytes[3] == 0x33);
+	ok1(u64.u64_bytes[2] == 0x22);
+	ok1(u64.u64_bytes[1] == 0x11);
+	ok1(u64.u64_bytes[0] == 0x00);
+	ok1(be64_to_cpu(u64.u64) == 0x0011223344556677ULL);
+
+	u32.u32 = cpu_to_le32(0x00112233);
+	ok1(u32.u32_bytes[0] == 0x33);
+	ok1(u32.u32_bytes[1] == 0x22);
+	ok1(u32.u32_bytes[2] == 0x11);
+	ok1(u32.u32_bytes[3] == 0x00);
+	ok1(le32_to_cpu(u32.u32) == 0x00112233);
+
+	u32.u32 = cpu_to_be32(0x00112233);
+	ok1(u32.u32_bytes[3] == 0x33);
+	ok1(u32.u32_bytes[2] == 0x22);
+	ok1(u32.u32_bytes[1] == 0x11);
+	ok1(u32.u32_bytes[0] == 0x00);
+	ok1(be32_to_cpu(u32.u32) == 0x00112233);
+
+	u16.u16 = cpu_to_le16(0x0011);
+	ok1(u16.u16_bytes[0] == 0x11);
+	ok1(u16.u16_bytes[1] == 0x00);
+	ok1(le16_to_cpu(u16.u16) == 0x0011);
+
+	u16.u16 = cpu_to_be16(0x0011);
+	ok1(u16.u16_bytes[1] == 0x11);
+	ok1(u16.u16_bytes[0] == 0x00);
+	ok1(be16_to_cpu(u16.u16) == 0x0011);
+
+	exit(exit_status());
+}