@@ -243,6 +243,29 @@ typedef struct {
#define ATOMIC64_INIT(i) { (i) }
+#ifdef CONFIG_ARM_LPAE
+static inline u64 atomic64_read(const atomic64_t *v)
+{
+ u64 result;
+
+ __asm__ __volatile__("@ atomic64_read\n"
+" ldrd %0, %H0, [%1]"
+ : "=&r" (result)
+ : "r" (&v->counter), "Qo" (v->counter)
+ );
+
+ return result;
+}
+
+static inline void atomic64_set(atomic64_t *v, u64 i)
+{
+ __asm__ __volatile__("@ atomic64_set\n"
+" strd %2, %H2, [%1]"
+ : "=Qo" (v->counter)
+ : "r" (&v->counter), "r" (i)
+ );
+}
+#else
static inline u64 atomic64_read(const atomic64_t *v)
{
u64 result;
@@ -269,6 +292,7 @@ static inline void atomic64_set(atomic64_t *v, u64 i)
: "r" (&v->counter), "r" (i)
: "cc");
}
+#endif
static inline void atomic64_add(u64 i, atomic64_t *v)
{
To ease page table updates with 64-bit descriptors, CPUs implementing LPAE are required to implement ldrd/strd as atomic operations. This patch uses these accessors instead of the exclusive variants when performing atomic64_{read,set} on LPAE systems. Signed-off-by: Will Deacon <will.deacon@arm.com> --- arch/arm/include/asm/atomic.h | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+)