xtensa: add s32c1i-based atomic ops implementations

[deliverable/linux.git] / arch / xtensa / include / asm / cmpxchg.h

diff --git a/arch/xtensa/include/asm/cmpxchg.h b/arch/xtensa/include/asm/cmpxchg.h
index 64dad04a9d276453cfca46df63eabcad816a07e2..25869a190490468d3e8420762f8d78a106c19f32 100644 (file)
--- a/arch/xtensa/include/asm/cmpxchg.h
+++ b/arch/xtensa/include/asm/cmpxchg.h
@@ -22,17 +22,30 @@
 static inline unsigned long
 __cmpxchg_u32(volatile int *p, int old, int new)
 {
-  __asm__ __volatile__("rsil    a15, "__stringify(LOCKLEVEL)"\n\t"
-                      "l32i    %0, %1, 0              \n\t"
-                      "bne     %0, %2, 1f             \n\t"
-                      "s32i    %3, %1, 0              \n\t"
-                      "1:                             \n\t"
-                      "wsr     a15, ps                \n\t"
-                      "rsync                          \n\t"
-                      : "=&a" (old)
-                      : "a" (p), "a" (old), "r" (new)
-                      : "a15", "memory");
-  return old;
+#if XCHAL_HAVE_S32C1I
+       __asm__ __volatile__(
+                       "       wsr     %2, scompare1\n"
+                       "       s32c1i  %0, %1, 0\n"
+                       : "+a" (new)
+                       : "a" (p), "a" (old)
+                       : "memory"
+                       );
+
+       return new;
+#else
+       __asm__ __volatile__(
+                       "       rsil    a15, "__stringify(LOCKLEVEL)"\n"
+                       "       l32i    %0, %1, 0\n"
+                       "       bne     %0, %2, 1f\n"
+                       "       s32i    %3, %1, 0\n"
+                       "1:\n"
+                       "       wsr     a15, ps\n"
+                       "       rsync\n"
+                       : "=&a" (old)
+                       : "a" (p), "a" (old), "r" (new)
+                       : "a15", "memory");
+       return old;
+#endif
 }
 /* This function doesn't exist, so you'll get a linker error
  * if something tries to do an invalid cmpxchg(). */
@@ -93,16 +106,32 @@ static inline unsigned long __cmpxchg_local(volatile void *ptr,
 
 static inline unsigned long xchg_u32(volatile int * m, unsigned long val)
 {
-  unsigned long tmp;
-  __asm__ __volatile__("rsil    a15, "__stringify(LOCKLEVEL)"\n\t"
-                      "l32i    %0, %1, 0              \n\t"
-                      "s32i    %2, %1, 0              \n\t"
-                      "wsr     a15, ps                \n\t"
-                      "rsync                          \n\t"
-                      : "=&a" (tmp)
-                      : "a" (m), "a" (val)
-                      : "a15", "memory");
-  return tmp;
+#if XCHAL_HAVE_S32C1I
+       unsigned long tmp, result;
+       __asm__ __volatile__(
+                       "1:     l32i    %1, %2, 0\n"
+                       "       mov     %0, %3\n"
+                       "       wsr     %1, scompare1\n"
+                       "       s32c1i  %0, %2, 0\n"
+                       "       bne     %0, %1, 1b\n"
+                       : "=&a" (result), "=&a" (tmp)
+                       : "a" (m), "a" (val)
+                       : "memory"
+                       );
+       return result;
+#else
+       unsigned long tmp;
+       __asm__ __volatile__(
+                       "       rsil    a15, "__stringify(LOCKLEVEL)"\n"
+                       "       l32i    %0, %1, 0\n"
+                       "       s32i    %2, %1, 0\n"
+                       "       wsr     a15, ps\n"
+                       "       rsync\n"
+                       : "=&a" (tmp)
+                       : "a" (m), "a" (val)
+                       : "a15", "memory");
+       return tmp;
+#endif
 }
 
 #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))