tile: Provide atomic_{or,xor,and}

Implement atomic logic ops -- atomic_{or,xor,and}.

For tilegx, these are relatively straightforward; the architecture
provides atomic "or" and "and", both 32-bit and 64-bit.  To support
xor we provide a loop using "cmpexch".

For the older 32-bit tilepro architecture, we have to extend
the set of low-level assembly routines to include 32-bit "and",
as well as all three 64-bit routines.  Somewhat confusingly,
some 32-bit versions are already used by the bitops inlines, with
parameter types appropriate for bitops, so we have to do a bit of
casting to match "int" to "unsigned long".

Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1436474297-32187-1-git-send-email-cmetcalf@ezchip.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 42 insertions, 0 deletions

diff --git a/arch/tile/include/asm/atomic_64.h b/arch/tile/include/asm/atomic_64.h
index 0496970cef82..d07d9fc6e2a1 100644
--- a/arch/tile/include/asm/atomic_64.h
+++ b/arch/tile/include/asm/atomic_64.h
@@ -58,6 +58,28 @@ static inline int __atomic_add_unless(atomic_t *v, int a, int u)
 	return oldval;
 }
 
+#define CONFIG_ARCH_HAS_ATOMIC_OR
+
+static inline void atomic_and(int i, atomic_t *v)
+{
+	__insn_fetchand4((void *)&v->counter, i);
+}
+
+static inline void atomic_or(int i, atomic_t *v)
+{
+	__insn_fetchor4((void *)&v->counter, i);
+}
+
+static inline void atomic_xor(int i, atomic_t *v)
+{
+	int guess, oldval = v->counter;
+	do {
+		guess = oldval;
+		__insn_mtspr(SPR_CMPEXCH_VALUE, guess);
+		oldval = __insn_cmpexch4(&v->counter, guess ^ i);
+	} while (guess != oldval);
+}
+
 /* Now the true 64-bit operations. */
 
 #define ATOMIC64_INIT(i)	{ (i) }
@@ -91,6 +113,26 @@ static inline long atomic64_add_unless(atomic64_t *v, long a, long u)
 	return oldval != u;
 }
 
+static inline void atomic64_and(long i, atomic64_t *v)
+{
+	__insn_fetchand((void *)&v->counter, i);
+}
+
+static inline void atomic64_or(long i, atomic64_t *v)
+{
+	__insn_fetchor((void *)&v->counter, i);
+}
+
+static inline void atomic64_xor(long i, atomic64_t *v)
+{
+	long guess, oldval = v->counter;
+	do {
+		guess = oldval;
+		__insn_mtspr(SPR_CMPEXCH_VALUE, guess);
+		oldval = __insn_cmpexch(&v->counter, guess ^ i);
+	} while (guess != oldval);
+}
+
 #define atomic64_sub_return(i, v)	atomic64_add_return(-(i), (v))
 #define atomic64_sub(i, v)		atomic64_add(-(i), (v))
 #define atomic64_inc_return(v)		atomic64_add_return(1, (v))