csky: Misc headers

This patch adds csky registers' definition, bitops, byteorder,
asm-offsets codes.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

arch/csky/include/asm/reg_ops.h

@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __ASM_REGS_OPS_H
+#define __ASM_REGS_OPS_H
+
+#define mfcr(reg)		\
+({				\
+	unsigned int tmp;	\
+	asm volatile(		\
+	"mfcr %0, "reg"\n"	\
+	: "=r"(tmp)		\
+	:			\
+	: "memory");		\
+	tmp;			\
+})
+
+#define mtcr(reg, val)		\
+({				\
+	asm volatile(		\
+	"mtcr %0, "reg"\n"	\
+	:			\
+	: "r"(val)		\
+	: "memory");		\
+})
+
+#endif /* __ASM_REGS_OPS_H */