[v3 01/24] eal/loongarch: add atomic operations for LoongArch

[Min Zhou <zhoumin@loongson.cn>]

This patch adds architecture specific atomic operations for
LoongArch architecture. These implementations use standard atomics
of toolchain and heavily reference generic atomics codes.

Signed-off-by: Min Zhou <zhoumin@loongson.cn>
---
 lib/eal/loongarch/include/rte_atomic.h | 253 +++++++++++++++++++++++++
 1 file changed, 253 insertions(+)
 create mode 100644 lib/eal/loongarch/include/rte_atomic.h

diff --git a/lib/eal/loongarch/include/rte_atomic.h b/lib/eal/loongarch/include/rte_atomic.h
new file mode 100644
index 0000000000..8e007e7f76
--- /dev/null
+++ b/lib/eal/loongarch/include/rte_atomic.h
@@ -0,0 +1,253 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2022 Loongson Technology Corporation Limited
+ */
+
+#ifndef _RTE_ATOMIC_LOONGARCH_H_
+#define _RTE_ATOMIC_LOONGARCH_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+#include "generic/rte_atomic.h"
+
+/**
+ * LoongArch Synchronize
+ */
+static inline void synchronize(void)
+{
+	__asm__ __volatile__("dbar 0":::"memory");
+}
+
+/**
+ * General memory barrier.
+ *
+ * Guarantees that the LOAD and STORE operations generated before the
+ * barrier occur before the LOAD and STORE operations generated after.
+ * This function is architecture dependent.
+ */
+#define rte_mb() synchronize()
+
+/**
+ * Write memory barrier.
+ *
+ * Guarantees that the STORE operations generated before the barrier
+ * occur before the STORE operations generated after.
+ * This function is architecture dependent.
+ */
+#define rte_wmb() synchronize()
+
+/**
+ * Read memory barrier.
+ *
+ * Guarantees that the LOAD operations generated before the barrier
+ * occur before the LOAD operations generated after.
+ * This function is architecture dependent.
+ */
+#define rte_rmb() synchronize()
+
+#define rte_smp_mb() rte_mb()
+
+#define rte_smp_wmb() rte_mb()
+
+#define rte_smp_rmb() rte_mb()
+
+#define rte_io_mb() rte_mb()
+
+#define rte_io_wmb() rte_mb()
+
+#define rte_io_rmb() rte_mb()
+
+static __rte_always_inline void
+rte_atomic_thread_fence(int memorder)
+{
+	__atomic_thread_fence(memorder);
+}
+
+#ifndef RTE_FORCE_INTRINSICS
+/*------------------------- 16 bit atomic operations -------------------------*/
+static inline int
+rte_atomic16_cmpset(volatile uint16_t *dst, uint16_t exp, uint16_t src)
+{
+	return __sync_bool_compare_and_swap(dst, exp, src);
+}
+
+static inline uint16_t
+rte_atomic16_exchange(volatile uint16_t *dst, uint16_t val)
+{
+#if defined(__clang__)
+	return __atomic_exchange_n(dst, val, __ATOMIC_SEQ_CST);
+#else
+	return __atomic_exchange_2(dst, val, __ATOMIC_SEQ_CST);
+#endif
+}
+
+static inline void
+rte_atomic16_inc(rte_atomic16_t *v)
+{
+	rte_atomic16_add(v, 1);
+}
+
+static inline void
+rte_atomic16_dec(rte_atomic16_t *v)
+{
+	rte_atomic16_sub(v, 1);
+}
+
+static inline int rte_atomic16_inc_and_test(rte_atomic16_t *v)
+{
+	return __sync_add_and_fetch(&v->cnt, 1) == 0;
+}
+
+static inline int rte_atomic16_dec_and_test(rte_atomic16_t *v)
+{
+	return __sync_sub_and_fetch(&v->cnt, 1) == 0;
+}
+
+static inline int rte_atomic16_test_and_set(rte_atomic16_t *v)
+{
+	return rte_atomic16_cmpset((volatile uint16_t *)&v->cnt, 0, 1);
+}
+
+/*------------------------- 32 bit atomic operations -------------------------*/
+static inline int
+rte_atomic32_cmpset(volatile uint32_t *dst, uint32_t exp, uint32_t src)
+{
+	return __sync_bool_compare_and_swap(dst, exp, src);
+}
+
+static inline uint32_t
+rte_atomic32_exchange(volatile uint32_t *dst, uint32_t val)
+{
+#if defined(__clang__)
+	return __atomic_exchange_n(dst, val, __ATOMIC_SEQ_CST);
+#else
+	return __atomic_exchange_4(dst, val, __ATOMIC_SEQ_CST);
+#endif
+}
+
+static inline void
+rte_atomic32_inc(rte_atomic32_t *v)
+{
+	rte_atomic32_add(v, 1);
+}
+
+static inline void
+rte_atomic32_dec(rte_atomic32_t *v)
+{
+	rte_atomic32_sub(v, 1);
+}
+
+static inline int rte_atomic32_inc_and_test(rte_atomic32_t *v)
+{
+	return __sync_add_and_fetch(&v->cnt, 1) == 0;
+}
+
+static inline int rte_atomic32_dec_and_test(rte_atomic32_t *v)
+{
+	return __sync_sub_and_fetch(&v->cnt, 1) == 0;
+}
+
+static inline int rte_atomic32_test_and_set(rte_atomic32_t *v)
+{
+	return rte_atomic32_cmpset((volatile uint32_t *)&v->cnt, 0, 1);
+}
+
+/*------------------------- 64 bit atomic operations -------------------------*/
+static inline int
+rte_atomic64_cmpset(volatile uint64_t *dst, uint64_t exp, uint64_t src)
+{
+	return __sync_bool_compare_and_swap(dst, exp, src);
+}
+
+static inline uint64_t
+rte_atomic64_exchange(volatile uint64_t *dst, uint64_t val)
+{
+#if defined(__clang__)
+	return __atomic_exchange_n(dst, val, __ATOMIC_SEQ_CST);
+#else
+	return __atomic_exchange_8(dst, val, __ATOMIC_SEQ_CST);
+#endif
+}
+
+static inline void
+rte_atomic64_init(rte_atomic64_t *v)
+{
+	v->cnt = 0;
+}
+
+static inline int64_t
+rte_atomic64_read(rte_atomic64_t *v)
+{
+	return v->cnt;
+}
+
+static inline void
+rte_atomic64_set(rte_atomic64_t *v, int64_t new_value)
+{
+	v->cnt = new_value;
+}
+
+static inline void
+rte_atomic64_add(rte_atomic64_t *v, int64_t inc)
+{
+	__sync_fetch_and_add(&v->cnt, inc);
+}
+
+static inline void
+rte_atomic64_sub(rte_atomic64_t *v, int64_t dec)
+{
+	__sync_fetch_and_sub(&v->cnt, dec);
+}
+
+static inline void
+rte_atomic64_inc(rte_atomic64_t *v)
+{
+	rte_atomic64_add(v, 1);
+}
+
+static inline void
+rte_atomic64_dec(rte_atomic64_t *v)
+{
+	rte_atomic64_sub(v, 1);
+}
+
+static inline int64_t
+rte_atomic64_add_return(rte_atomic64_t *v, int64_t inc)
+{
+	return __sync_add_and_fetch(&v->cnt, inc);
+}
+
+static inline int64_t
+rte_atomic64_sub_return(rte_atomic64_t *v, int64_t dec)
+{
+	return __sync_sub_and_fetch(&v->cnt, dec);
+}
+
+static inline int rte_atomic64_inc_and_test(rte_atomic64_t *v)
+{
+	return rte_atomic64_add_return(v, 1) == 0;
+}
+
+static inline int rte_atomic64_dec_and_test(rte_atomic64_t *v)
+{
+	return rte_atomic64_sub_return(v, 1) == 0;
+}
+
+static inline int rte_atomic64_test_and_set(rte_atomic64_t *v)
+{
+	return rte_atomic64_cmpset((volatile uint64_t *)&v->cnt, 0, 1);
+}
+
+static inline void rte_atomic64_clear(rte_atomic64_t *v)
+{
+	rte_atomic64_set(v, 0);
+}
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _RTE_ATOMIC_LOONGARCH_H_ */
-- 
2.31.1