diff --git a/sysdeps/m68k/m68020/bits/atomic.h b/sysdeps/m68k/m68020/bits/atomic.h
index 80b5b8f3bf..6978b27cde 100644
--- a/sysdeps/m68k/m68020/bits/atomic.h
+++ b/sysdeps/m68k/m68020/bits/atomic.h
@@ -179,18 +179,52 @@ typedef uintmax_t uatomic_max_t;
 	      }								      \
 	    })
 
-#define atomic_decrement_and_test(mem) \
+#define atomic_increment_and_test(mem) \
   ({ char __result;							      \
      if (sizeof (*(mem)) == 1)						      \
-       __asm __volatile ("subq%.b %#1,%1; scs %0"			      \
+       __asm __volatile ("addq%.b %#1,%1; seq %0"			      \
 			 : "=dm" (__result), "=m" (*(mem))		      \
 			 : "1" (*(mem)));				      \
      else if (sizeof (*(mem)) == 2)					      \
-       __asm __volatile ("subq%.w %#1,%1; scs %0"			      \
+       __asm __volatile ("addq%.w %#1,%1; seq %0"			      \
 			 : "=dm" (__result), "=m" (*(mem))		      \
 			 : "1" (*(mem)));				      \
      else if (sizeof (*(mem)) == 4)					      \
-       __asm __volatile ("subq%.l %#1,%1; scs %0"			      \
+       __asm __volatile ("addq%.l %#1,%1; seq %0"			      \
+			 : "=dm" (__result), "=m" (*(mem))		      \
+			 : "1" (*(mem)));				      \
+     else								      \
+       {								      \
+	 __typeof (mem) __memp = (mem);					      \
+	 __typeof (*(mem)) __oldval = *__memp;				      \
+	 __typeof (*(mem)) __temp;					      \
+	 __asm __volatile ("1: move%.l %1,%2;"				      \
+			   "   move%.l %R1,%R2;"			      \
+			   "   addq%.l %#1,%2;"				      \
+			   "   addx%.l %5,%R2;"				      \
+			   "   seq %0;"					      \
+			   "   cas2%.l %1:%R1,%2:%R2,(%3):(%4);"	      \
+			   "   jbne 1b"					      \
+			   : "=&dm" (__result), "=d" (__oldval),	      \
+			     "=&d" (__temp)				      \
+			   : "r" (__memp), "r" ((char *) __memp + 4),	      \
+			     "d" (0), "1" (__oldval)			      \
+			   : "memory");					      \
+       }								      \
+     __result; })
+
+#define atomic_decrement_and_test(mem) \
+  ({ char __result;							      \
+     if (sizeof (*(mem)) == 1)						      \
+       __asm __volatile ("subq%.b %#1,%1; seq %0"			      \
+			 : "=dm" (__result), "=m" (*(mem))		      \
+			 : "1" (*(mem)));				      \
+     else if (sizeof (*(mem)) == 2)					      \
+       __asm __volatile ("subq%.w %#1,%1; seq %0"			      \
+			 : "=dm" (__result), "=m" (*(mem))		      \
+			 : "1" (*(mem)));				      \
+     else if (sizeof (*(mem)) == 4)					      \
+       __asm __volatile ("subq%.l %#1,%1; seq %0"			      \
 			 : "=dm" (__result), "=m" (*(mem))		      \
 			 : "1" (*(mem)));				      \
      else								      \
@@ -202,7 +236,7 @@ typedef uintmax_t uatomic_max_t;
 			   "   move%.l %R1,%R2;"			      \
 			   "   subq%.l %#1,%2;"				      \
 			   "   subx%.l %5,%R2;"				      \
-			   "   scs %0;"					      \
+			   "   seq %0;"					      \
 			   "   cas2%.l %1:%R1,%2:%R2,(%3):(%4);"	      \
 			   "   jbne 1b"					      \
 			   : "=&dm" (__result), "=d" (__oldval),	      \