From dafb78443a5e5dcdc45667822907bc7980fab4cd Mon Sep 17 00:00:00 2001
From: Alberto Escolar Piedras <alberto.escolar.piedras@nordicsemi.no>
Date: Fri, 13 Oct 2023 18:30:13 +0200
Subject: [PATCH] Add support for hosted test environments

Add a new hosted test environment "processor".

This is meant as a build target used when the
code is not built for a real target
but as part of a test in a hosted environment
(for ex. as a test environment like Zephyr's
native_sim target).

When building for this target PROJECT_PROCESSOR
should be set as "hosted".

In this, the "metal_sleep_usec()" call
is expected to be provided by the system folder
headers.

Signed-off-by: Alberto Escolar Piedras <alberto.escolar.piedras@nordicsemi.no>
---
 lib/processor/hosted/CMakeLists.txt |  2 ++
 lib/processor/hosted/atomic.h       | 15 +++++++++++++++
 lib/processor/hosted/cpu.h          | 22 ++++++++++++++++++++++
 3 files changed, 39 insertions(+)
 create mode 100644 lib/processor/hosted/CMakeLists.txt
 create mode 100644 lib/processor/hosted/atomic.h
 create mode 100644 lib/processor/hosted/cpu.h

diff --git a/lib/processor/hosted/CMakeLists.txt b/lib/processor/hosted/CMakeLists.txt
new file mode 100644
index 00000000..13ce0230
--- /dev/null
+++ b/lib/processor/hosted/CMakeLists.txt
@@ -0,0 +1,2 @@
+collect (PROJECT_LIB_HEADERS atomic.h)
+collect (PROJECT_LIB_HEADERS cpu.h)
diff --git a/lib/processor/hosted/atomic.h b/lib/processor/hosted/atomic.h
new file mode 100644
index 00000000..ed153c30
--- /dev/null
+++ b/lib/processor/hosted/atomic.h
@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2023 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+/*
+ * @file	hosted/atomic.h
+ * @brief	Hosted environment atomic primitives for libmetal.
+ */
+
+#ifndef __METAL_HOSTED_ATOMIC__H__
+#define __METAL_HOSTED_ATOMIC__H__
+
+#endif /* __METAL_HOSTED_ATOMIC__H__ */
diff --git a/lib/processor/hosted/cpu.h b/lib/processor/hosted/cpu.h
new file mode 100644
index 00000000..be8a1680
--- /dev/null
+++ b/lib/processor/hosted/cpu.h
@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2023 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+/*
+ * @file	hosted/cpu.h
+ * @brief	Hosted environment CPU specific primitives
+ */
+
+#include <metal/sys.h>
+
+#ifndef __METAL_HOSTED_CPU__H__
+#define __METAL_HOSTED_CPU__H__
+
+static inline void metal_cpu_yield(void)
+{
+	metal_wait_usec(10);
+}
+
+#endif /* __METAL_HOSTED_CPU__H__ */