Move display_options functions to their own header

Before adding one more function, create a separate header to help reduce
the size of common.h. Add the missing function comments and tidy up.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

include/common.h

@@ -192,22 +192,8 @@ int	cpu_init(void);
 
 /* */
 phys_size_t initdram (int);
-int	display_options (void);
 
-/**
- * print_size() - Print a size with a suffic
- *
- * print sizes as "xxx KiB", "xxx.y KiB", "xxx MiB", "xxx.y MiB",
- * xxx GiB, xxx.y GiB, etc as needed; allow for optional trailing string
- * (like "\n")
- *
- * @size:	Size to print
- * @suffix	String to print after the size
- */
-void print_size(uint64_t size, const char *suffix);
-
-int print_buffer(ulong addr, const void *data, uint width, uint count,
-		 uint linelen);
+#include <display_options.h>
 
 /* common/main.c */
 void	main_loop	(void);

include/display_options.h

@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2015 Google, Inc
+ *
+ * (C) Copyright 2000-2002
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __DISPLAY_OPTIONS_H
+#define __DISPLAY_OPTIONS_H
+
+/**
+ * print_size() - Print a size with a suffix
+ *
+ * Print sizes as "xxx KiB", "xxx.y KiB", "xxx MiB", "xxx.y MiB",
+ * xxx GiB, xxx.y GiB, etc as needed; allow for optional trailing string
+ * (like "\n")
+ *
+ * @size:	Size to print
+ * @suffix	String to print after the size
+ */
+void print_size(uint64_t size, const char *suffix);
+
+/**
+ * print_buffer() - Print data buffer in hex and ascii form
+ *
+ * Data reads are buffered so that each memory address is only read once.
+ * This is useful when displaying the contents of volatile registers.
+ *
+ * @addr:	Starting address to display at start of line
+ * @data:	pointer to data buffer
+ * @width:	data value width.  May be 1, 2, or 4.
+ * @count:	number of values to display
+ * @linelen:	Number of values to print per line; specify 0 for default length
+ */
+int print_buffer(ulong addr, const void *data, uint width, uint count,
+		 uint linelen);
+
+/**
+ * display_options() - display the version string / build tag
+ *
+ * This displays the U-Boot version string. If a build tag is available this
+ * is displayed also.
+ */
+int display_options(void);
+
+#endif

lib/display_options.c

@@ -63,19 +63,6 @@ void print_size(uint64_t size, const char *s)
 	printf (" %ciB%s", c, s);
 }
 
-/*
- * Print data buffer in hex and ascii form to the terminal.
- *
- * data reads are buffered so that each memory address is only read once.
- * Useful when displaying the contents of volatile registers.
- *
- * parameters:
- *    addr: Starting address to display at start of line
- *    data: pointer to data buffer
- *    width: data value width.  May be 1, 2, or 4.
- *    count: number of values to display
- *    linelen: Number of values to print per line; specify 0 for default length
- */
 #define MAX_LINE_LENGTH_BYTES (64)
 #define DEFAULT_LINE_LENGTH_BYTES (16)
 int print_buffer(ulong addr, const void *data, uint width, uint count,