From c5eeb0f4eb90a3c2ae50ae715576b321c784cf14 Mon Sep 17 00:00:00 2001
From: Evgeniy Paltsev <PaltsevEvgeniy@gmail.com>
Date: Thu, 19 Aug 2021 15:44:30 +0300
Subject: [PATCH] ARC: MWDT: add locking interface implementation

ARC MWDT libraries require to implement locking interface
otherwise not all of functionality is guarantee to be
thread-safe.

So, let's implement locking interface.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Evgeniy Paltsev <PaltsevEvgeniy@gmail.com>
---
 lib/libc/arcmwdt/CMakeLists.txt |  1 +
 lib/libc/arcmwdt/threading.c    | 64 +++++++++++++++++++++++++++++++++
 2 files changed, 65 insertions(+)
 create mode 100644 lib/libc/arcmwdt/threading.c

diff --git a/lib/libc/arcmwdt/CMakeLists.txt b/lib/libc/arcmwdt/CMakeLists.txt
index 1db97738e0f..da53b56bc65 100644
--- a/lib/libc/arcmwdt/CMakeLists.txt
+++ b/lib/libc/arcmwdt/CMakeLists.txt
@@ -6,4 +6,5 @@ zephyr_library()
 zephyr_library_sources(
   arcmwdt-string.c
   libc-hooks.c
+  threading.c
 )
diff --git a/lib/libc/arcmwdt/threading.c b/lib/libc/arcmwdt/threading.c
new file mode 100644
index 00000000000..a2dd4bfffe0
--- /dev/null
+++ b/lib/libc/arcmwdt/threading.c
@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 2021 Synopsys.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifdef CONFIG_MULTITHREADING
+
+#include <init.h>
+#include <kernel.h>
+#include <sys/__assert.h>
+#include <sys/mutex.h>
+#include <logging/log.h>
+#include <../lib/src/c/inc/internal/thread.h>
+
+#ifndef CONFIG_USERSPACE
+#define ARCMWDT_DYN_LOCK_SZ	(sizeof(struct k_mutex))
+#define ARCMWDT_MAX_DYN_LOCKS	10
+
+K_MEM_SLAB_DEFINE(z_arcmwdt_lock_slab, ARCMWDT_DYN_LOCK_SZ, ARCMWDT_MAX_DYN_LOCKS, sizeof(void *));
+#endif /* !CONFIG_USERSPACE */
+
+LOG_MODULE_DECLARE(os, CONFIG_KERNEL_LOG_LEVEL);
+
+void _mwmutex_create(_lock_t *mutex_ptr)
+{
+	bool alloc_fail;
+#ifdef CONFIG_USERSPACE
+	*mutex_ptr = k_object_alloc(K_OBJ_MUTEX);
+	alloc_fail = (*mutex_ptr == NULL);
+#else
+	alloc_fail = !!k_mem_slab_alloc(&z_arcmwdt_lock_slab, mutex_ptr, K_NO_WAIT);
+#endif /* CONFIG_USERSPACE */
+
+	if (alloc_fail) {
+		LOG_ERR("MWDT lock allocation failed");
+		k_panic();
+	}
+
+	k_mutex_init((struct k_mutex *)*mutex_ptr);
+}
+
+void _mwmutex_delete(_lock_t *mutex_ptr)
+{
+	__ASSERT_NO_MSG(mutex_ptr != NULL);
+#ifdef CONFIG_USERSPACE
+	k_object_release(mutex_ptr);
+#else
+	k_mem_slab_free(&z_arcmwdt_lock_slab, mutex_ptr);
+#endif /* CONFIG_USERSPACE */
+}
+
+void _mwmutex_lock(_lock_t mutex)
+{
+	__ASSERT_NO_MSG(mutex != NULL);
+	k_mutex_lock((struct k_mutex *)mutex, K_FOREVER);
+}
+
+void _mwmutex_unlock(_lock_t mutex)
+{
+	__ASSERT_NO_MSG(mutex != NULL);
+	k_mutex_unlock((struct k_mutex *)mutex);
+}
+#endif /* CONFIG_MULTITHREADING */