diff --git a/tools/bmp_logo.c b/tools/bmp_logo.c
index e8dd8c8..47228d2 100644
--- a/tools/bmp_logo.c
+++ b/tools/bmp_logo.c
@@ -1,15 +1,4 @@
-#include <stdio.h>
-#include <stdlib.h>
-
-#if defined(__linux__)
-#include <stdint.h>
-#else
-#ifdef __CYGWIN__
-#include "elf.h"
-#else
-#include <inttypes.h>
-#endif
-#endif
+#include "compiler.h"
 
 typedef struct bitmap_s {		/* bitmap description */
 	uint16_t width;
diff --git a/tools/img2srec.c b/tools/img2srec.c
index b04abbd..f10379f 100644
--- a/tools/img2srec.c
+++ b/tools/img2srec.c
@@ -52,6 +52,7 @@
 |  INCLUDES
 |*************************************************************************/
 
+#include "os_support.h"
 #include <stddef.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -61,8 +62,6 @@
 #include <unistd.h>
 #include <errno.h>
 
-extern int errno;
-
 /*************************************************************************
 |  DEFINES
 |*************************************************************************/
diff --git a/tools/mingw_support.h b/tools/mingw_support.h
index 1fb6c93..9e45e64 100644
--- a/tools/mingw_support.h
+++ b/tools/mingw_support.h
@@ -34,9 +34,6 @@
 #define MAP_SHARED	0x01		/* Share changes */
 #define MAP_PRIVATE	0x02		/* Changes are private */
 
-/* Return value of `mmap' in case of an error */
-#define MAP_FAILED	((void *) -1)
-
 /* Windows 64-bit access macros */
 #define LODWORD(x) ((DWORD)((DWORDLONG)(x)))
 #define HIDWORD(x) ((DWORD)(((DWORDLONG)(x) >> 32) & 0xffffffff))
diff --git a/tools/mkimage.c b/tools/mkimage.c
index 967fe9a..02cdb95 100644
--- a/tools/mkimage.c
+++ b/tools/mkimage.c
@@ -25,12 +25,6 @@
 #include "mkimage.h"
 #include <image.h>
 
-extern int errno;
-
-#ifndef MAP_FAILED
-#define MAP_FAILED (void *)(-1)
-#endif
-
 extern	unsigned long	crc32 (unsigned long crc, const char *buf, unsigned int len);
 static	void		copy_file (int, const char *, int);
 static	void		usage (void);
@@ -502,7 +496,7 @@
 	 */
 	memcpy (hdr, ptr, sizeof(image_header_t));
 
-	if (ntohl(hdr->ih_magic) != IH_MAGIC) {
+	if (be32_to_cpu(hdr->ih_magic) != IH_MAGIC) {
 		fprintf (stderr,
 			"%s: Bad Magic Number: \"%s\" is no valid image\n",
 			cmdname, imagefile);
@@ -512,8 +506,8 @@
 	data = (char *)hdr;
 	len  = sizeof(image_header_t);
 
-	checksum = ntohl(hdr->ih_hcrc);
-	hdr->ih_hcrc = htonl(0);	/* clear for re-calculation */
+	checksum = be32_to_cpu(hdr->ih_hcrc);
+	hdr->ih_hcrc = cpu_to_be32(0);	/* clear for re-calculation */
 
 	if (crc32 (0, data, len) != checksum) {
 		fprintf (stderr,
@@ -525,7 +519,7 @@
 	data = ptr + sizeof(image_header_t);
 	len  = image_size - sizeof(image_header_t) ;
 
-	if (crc32 (0, data, len) != ntohl(hdr->ih_dcrc)) {
+	if (crc32 (0, data, len) != be32_to_cpu(hdr->ih_dcrc)) {
 		fprintf (stderr,
 			"%s: ERROR: \"%s\" has corrupted data!\n",
 			cmdname, imagefile);
diff --git a/tools/mkimage.h b/tools/mkimage.h
index c8df6e1..70c53ad 100644
--- a/tools/mkimage.h
+++ b/tools/mkimage.h
@@ -26,14 +26,6 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#ifndef __WIN32__
-#include <netinet/in.h>		/* for host / network byte order conversions	*/
-#endif
-#ifdef __MINGW32__
-#include <stdint.h>
-#else
-#include <sys/mman.h>
-#endif
 #include <sys/stat.h>
 #include <time.h>
 #include <unistd.h>
@@ -53,28 +45,3 @@
 #define MKIMAGE_DEFAULT_DTC_OPTIONS	"-I dts -O dtb -p 500"
 #define MKIMAGE_MAX_DTC_CMDLINE_LEN	512
 #define MKIMAGE_DTC			"dtc"   /* assume dtc is in $PATH */
-
-#if defined(__BEOS__) || defined(__NetBSD__) || defined(__APPLE__)
-#include <inttypes.h>
-#endif
-
-#ifdef __WIN32__
-typedef unsigned int __u32;
-
-#define SWAP_LONG(x) \
-	((__u32)( \
-		(((__u32)(x) & (__u32)0x000000ffUL) << 24) | \
-		(((__u32)(x) & (__u32)0x0000ff00UL) <<  8) | \
-		(((__u32)(x) & (__u32)0x00ff0000UL) >>  8) | \
-		(((__u32)(x) & (__u32)0xff000000UL) >> 24) ))
-typedef		unsigned char	uint8_t;
-typedef		unsigned short	uint16_t;
-typedef		unsigned int	uint32_t;
-
-#define     ntohl(a)	SWAP_LONG(a)
-#define     htonl(a)	SWAP_LONG(a)
-#endif	/* __WIN32__ */
-
-#ifndef	O_BINARY		/* should be define'd on __WIN32__ */
-#define O_BINARY	0
-#endif
diff --git a/tools/os_support.c b/tools/os_support.c
index 001fe64..5b919aa 100644
--- a/tools/os_support.c
+++ b/tools/os_support.c
@@ -19,6 +19,7 @@
 /*
  * Include additional files required for supporting different operating systems
  */
+#include "compiler.h"
 #ifdef __MINGW32__
 #include "mingw_support.c"
 #endif
diff --git a/tools/os_support.h b/tools/os_support.h
index f6f86b0..7bf930e 100644
--- a/tools/os_support.h
+++ b/tools/os_support.h
@@ -19,6 +19,8 @@
 #ifndef __OS_SUPPORT_H_
 #define __OS_SUPPORT_H_
 
+#include "compiler.h"
+
 /*
  * Include additional files required for supporting different operating systems
  */
diff --git a/tools/ubsha1.c b/tools/ubsha1.c
index c4203ed..9774eea 100644
--- a/tools/ubsha1.c
+++ b/tools/ubsha1.c
@@ -28,9 +28,6 @@
 #include <fcntl.h>
 #include <errno.h>
 #include <string.h>
-#ifndef __MINGW32__
-#include <sys/mman.h>
-#endif
 #include <sys/stat.h>
 #include "sha1.h"
 
@@ -40,16 +37,6 @@
 #include <config.h>
 #undef	__ASSEMBLY__
 
-#ifndef	O_BINARY		/* should be define'd on __WIN32__ */
-#define O_BINARY	0
-#endif
-
-#ifndef MAP_FAILED
-#define MAP_FAILED (-1)
-#endif
-
-extern int errno;
-
 extern void sha1_csum (unsigned char *input, int ilen, unsigned char output[20]);
 
 int main (int argc, char **argv)