Merge git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc

* git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (78 commits)
  [PATCH] powerpc: Add FSL SEC node to documentation
  [PATCH] macintosh: tidy-up driver_register() return values
  [PATCH] powerpc: tidy-up of_register_driver()/driver_register() return values
  [PATCH] powerpc: via-pmu warning fix
  [PATCH] macintosh: cleanup the use of i2c headers
  [PATCH] powerpc: dont allow old RTC to be selected
  [PATCH] powerpc: make powerbook_sleep_grackle static
  [PATCH] powerpc: Fix warning in add_memory
  [PATCH] powerpc: update mailing list addresses
  [PATCH] powerpc: Remove calculation of io hole
  [PATCH] powerpc: iseries: Add bootargs to /chosen
  [PATCH] powerpc: iseries: Add /system-id, /model and /compatible
  [PATCH] powerpc: Add strne2a() to convert a string from EBCDIC to ASCII
  [PATCH] powerpc: iseries: Make more stuff static in platforms/iseries/mf.c
  [PATCH] powerpc: iseries: Remove pointless iSeries_(restart|power_off|halt)
  [PATCH] powerpc: iseries: mf related cleanups
  [PATCH] powerpc: Replace platform_is_lpar() with a firmware feature
  [PATCH] powerpc: trivial: Cleanup whitespace in cputable.h
  [PATCH] powerpc: Remove unused iommu_off logic from pSeries_init_early()
  [PATCH] powerpc: Unconfuse htab_bolt_mapping() callers
  ...

1 files changed, 24 insertions, 14 deletions

diff --git a/include/asm-powerpc/atomic.h b/include/asm-powerpc/atomic.h
index 147a38dcc766..bb3c0ab7e667 100644
--- a/include/asm-powerpc/atomic.h
+++ b/include/asm-powerpc/atomic.h
@@ -8,6 +8,7 @@
 typedef struct { volatile int counter; } atomic_t;
 
 #ifdef __KERNEL__
+#include <linux/compiler.h>
 #include <asm/synch.h>
 #include <asm/asm-compat.h>
 
@@ -176,20 +177,29 @@ static __inline__ int atomic_dec_return(atomic_t *v)
  * Atomically adds @a to @v, so long as it was not @u.
  * Returns non-zero if @v was not @u, and zero otherwise.
  */
-#define atomic_add_unless(v, a, u)                      \
-({                                                      \
-        int c, old;                                     \
-        c = atomic_read(v);                             \
-        for (;;) {                                      \
-                if (unlikely(c == (u)))                 \
-                        break;                          \
-                old = atomic_cmpxchg((v), c, c + (a));  \
-                if (likely(old == c))                   \
-                        break;                          \
-                c = old;                                \
-        }                                               \
-        c != (u);                                       \
-})
+static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
+{
+        int t;
+
+        __asm__ __volatile__ (
+        LWSYNC_ON_SMP
+"1:     lwarx   %0,0,%1         # atomic_add_unless\n\
+        cmpw    0,%0,%3 \n\
+        beq-    2f \n\
+        add     %0,%2,%0 \n"
+        PPC405_ERR77(0,%2)
+"       stwcx.  %0,0,%1 \n\
+        bne-    1b \n"
+        ISYNC_ON_SMP
+"       subf    %0,%2,%0 \n\
+2:"
+        : "=&r" (t)
+        : "r" (&v->counter), "r" (a), "r" (u)
+        : "cc", "memory");
+
+        return t != u;
+}
+
 #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
 
 #define atomic_sub_and_test(a, v)       (atomic_sub_return((a), (v)) == 0)