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-rw-r--r--arch/arm/Kconfig1
-rw-r--r--arch/arm/include/asm/atomic.h228
2 files changed, 229 insertions, 0 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index b224216c11d..762ae536f90 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -12,6 +12,7 @@ config ARM
select HAVE_IDE
select RTC_LIB
select SYS_SUPPORTS_APM_EMULATION
+ select GENERIC_ATOMIC64 if (!CPU_32v6K)
select HAVE_OPROFILE
select HAVE_ARCH_KGDB
select HAVE_KPROBES if (!XIP_KERNEL)
diff --git a/arch/arm/include/asm/atomic.h b/arch/arm/include/asm/atomic.h
index d0daeab2234..e8ddec2cb15 100644
--- a/arch/arm/include/asm/atomic.h
+++ b/arch/arm/include/asm/atomic.h
@@ -235,6 +235,234 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u)
#define smp_mb__before_atomic_inc() smp_mb()
#define smp_mb__after_atomic_inc() smp_mb()
+#ifndef CONFIG_GENERIC_ATOMIC64
+typedef struct {
+ u64 __aligned(8) counter;
+} atomic64_t;
+
+#define ATOMIC64_INIT(i) { (i) }
+
+static inline u64 atomic64_read(atomic64_t *v)
+{
+ u64 result;
+
+ __asm__ __volatile__("@ atomic64_read\n"
+" ldrexd %0, %H0, [%1]"
+ : "=&r" (result)
+ : "r" (&v->counter)
+ );
+
+ return result;
+}
+
+static inline void atomic64_set(atomic64_t *v, u64 i)
+{
+ u64 tmp;
+
+ __asm__ __volatile__("@ atomic64_set\n"
+"1: ldrexd %0, %H0, [%1]\n"
+" strexd %0, %2, %H2, [%1]\n"
+" teq %0, #0\n"
+" bne 1b"
+ : "=&r" (tmp)
+ : "r" (&v->counter), "r" (i)
+ : "cc");
+}
+
+static inline void atomic64_add(u64 i, atomic64_t *v)
+{
+ u64 result;
+ unsigned long tmp;
+
+ __asm__ __volatile__("@ atomic64_add\n"
+"1: ldrexd %0, %H0, [%2]\n"
+" adds %0, %0, %3\n"
+" adc %H0, %H0, %H3\n"
+" strexd %1, %0, %H0, [%2]\n"
+" teq %1, #0\n"
+" bne 1b"
+ : "=&r" (result), "=&r" (tmp)
+ : "r" (&v->counter), "r" (i)
+ : "cc");
+}
+
+static inline u64 atomic64_add_return(u64 i, atomic64_t *v)
+{
+ u64 result;
+ unsigned long tmp;
+
+ smp_mb();
+
+ __asm__ __volatile__("@ atomic64_add_return\n"
+"1: ldrexd %0, %H0, [%2]\n"
+" adds %0, %0, %3\n"
+" adc %H0, %H0, %H3\n"
+" strexd %1, %0, %H0, [%2]\n"
+" teq %1, #0\n"
+" bne 1b"
+ : "=&r" (result), "=&r" (tmp)
+ : "r" (&v->counter), "r" (i)
+ : "cc");
+
+ smp_mb();
+
+ return result;
+}
+
+static inline void atomic64_sub(u64 i, atomic64_t *v)
+{
+ u64 result;
+ unsigned long tmp;
+
+ __asm__ __volatile__("@ atomic64_sub\n"
+"1: ldrexd %0, %H0, [%2]\n"
+" subs %0, %0, %3\n"
+" sbc %H0, %H0, %H3\n"
+" strexd %1, %0, %H0, [%2]\n"
+" teq %1, #0\n"
+" bne 1b"
+ : "=&r" (result), "=&r" (tmp)
+ : "r" (&v->counter), "r" (i)
+ : "cc");
+}
+
+static inline u64 atomic64_sub_return(u64 i, atomic64_t *v)
+{
+ u64 result;
+ unsigned long tmp;
+
+ smp_mb();
+
+ __asm__ __volatile__("@ atomic64_sub_return\n"
+"1: ldrexd %0, %H0, [%2]\n"
+" subs %0, %0, %3\n"
+" sbc %H0, %H0, %H3\n"
+" strexd %1, %0, %H0, [%2]\n"
+" teq %1, #0\n"
+" bne 1b"
+ : "=&r" (result), "=&r" (tmp)
+ : "r" (&v->counter), "r" (i)
+ : "cc");
+
+ smp_mb();
+
+ return result;
+}
+
+static inline u64 atomic64_cmpxchg(atomic64_t *ptr, u64 old, u64 new)
+{
+ u64 oldval;
+ unsigned long res;
+
+ smp_mb();
+
+ do {
+ __asm__ __volatile__("@ atomic64_cmpxchg\n"
+ "ldrexd %1, %H1, [%2]\n"
+ "mov %0, #0\n"
+ "teq %1, %3\n"
+ "teqeq %H1, %H3\n"
+ "strexdeq %0, %4, %H4, [%2]"
+ : "=&r" (res), "=&r" (oldval)
+ : "r" (&ptr->counter), "r" (old), "r" (new)
+ : "cc");
+ } while (res);
+
+ smp_mb();
+
+ return oldval;
+}
+
+static inline u64 atomic64_xchg(atomic64_t *ptr, u64 new)
+{
+ u64 result;
+ unsigned long tmp;
+
+ smp_mb();
+
+ __asm__ __volatile__("@ atomic64_xchg\n"
+"1: ldrexd %0, %H0, [%2]\n"
+" strexd %1, %3, %H3, [%2]\n"
+" teq %1, #0\n"
+" bne 1b"
+ : "=&r" (result), "=&r" (tmp)
+ : "r" (&ptr->counter), "r" (new)
+ : "cc");
+
+ smp_mb();
+
+ return result;
+}
+
+static inline u64 atomic64_dec_if_positive(atomic64_t *v)
+{
+ u64 result;
+ unsigned long tmp;
+
+ smp_mb();
+
+ __asm__ __volatile__("@ atomic64_dec_if_positive\n"
+"1: ldrexd %0, %H0, [%2]\n"
+" subs %0, %0, #1\n"
+" sbc %H0, %H0, #0\n"
+" teq %H0, #0\n"
+" bmi 2f\n"
+" strexd %1, %0, %H0, [%2]\n"
+" teq %1, #0\n"
+" bne 1b\n"
+"2:"
+ : "=&r" (result), "=&r" (tmp)
+ : "r" (&v->counter)
+ : "cc");
+
+ smp_mb();
+
+ return result;
+}
+
+static inline int atomic64_add_unless(atomic64_t *v, u64 a, u64 u)
+{
+ u64 val;
+ unsigned long tmp;
+ int ret = 1;
+
+ smp_mb();
+
+ __asm__ __volatile__("@ atomic64_add_unless\n"
+"1: ldrexd %0, %H0, [%3]\n"
+" teq %0, %4\n"
+" teqeq %H0, %H4\n"
+" moveq %1, #0\n"
+" beq 2f\n"
+" adds %0, %0, %5\n"
+" adc %H0, %H0, %H5\n"
+" strexd %2, %0, %H0, [%3]\n"
+" teq %2, #0\n"
+" bne 1b\n"
+"2:"
+ : "=&r" (val), "=&r" (ret), "=&r" (tmp)
+ : "r" (&v->counter), "r" (u), "r" (a)
+ : "cc");
+
+ if (ret)
+ smp_mb();
+
+ return ret;
+}
+
+#define atomic64_add_negative(a, v) (atomic64_add_return((a), (v)) < 0)
+#define atomic64_inc(v) atomic64_add(1LL, (v))
+#define atomic64_inc_return(v) atomic64_add_return(1LL, (v))
+#define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
+#define atomic64_sub_and_test(a, v) (atomic64_sub_return((a), (v)) == 0)
+#define atomic64_dec(v) atomic64_sub(1LL, (v))
+#define atomic64_dec_return(v) atomic64_sub_return(1LL, (v))
+#define atomic64_dec_and_test(v) (atomic64_dec_return((v)) == 0)
+#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1LL, 0LL)
+
+#else /* !CONFIG_GENERIC_ATOMIC64 */
+#include <asm-generic/atomic64.h>
+#endif
#include <asm-generic/atomic-long.h>
#endif
#endif