建立工程，成功创建两个虚拟串口

source/OpenAMP/libmetal/lib/system/linux/condition.c

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+/*
+ * Copyright (c) 2016, Xilinx Inc. and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+/*
+ * @file	generic/condition.c
+ * @brief	Generic libmetal condition variable handling.
+ */
+
+#include <metal/condition.h>
+
+int metal_condition_wait(struct metal_condition *cv,
+				       metal_mutex_t *m)
+{
+	metal_mutex_t *tmpm = 0;
+	int v = 0;
+
+	/* Check if the mutex has been acquired */
+	if (!cv || !m || !metal_mutex_is_acquired(m))
+		return -EINVAL;
+
+	if (!atomic_compare_exchange_strong(&cv->m, &tmpm, m)) {
+		if (m != tmpm)
+			return -EINVAL;
+	}
+
+	v = atomic_load(&cv->wakeups);
+	atomic_fetch_add(&cv->waiters, 1);
+
+	/* Release the mutex before sleeping. */
+	metal_mutex_release(m);
+	syscall(SYS_futex, &cv->wakeups, FUTEX_WAIT, v, NULL, NULL, 0);
+	atomic_fetch_sub(&cv->waiters, 1);
+	/* Acquire the mutex after it's waken up. */
+	metal_mutex_acquire(m);
+
+	return 0;
+}