arm64: xenvm: Add Xen hypercall interface for arm64

This commit adds Xen hypervisor call interface for arm64 architecture.
This is needed for further development of Xen features in Zephyr.

Signed-off-by: Dmytro Firsov <[email protected]>

Author: firscity

arch/arm64/core/CMakeLists.txt

@@ -31,3 +31,5 @@ endif ()
 add_subdirectory_ifdef(CONFIG_ARM_MPU cortex_r/mpu)
 
 zephyr_cc_option_ifdef(CONFIG_USERSPACE -mno-outline-atomics)
+
+add_subdirectory_ifdef(CONFIG_SOC_XENVM xen)

arch/arm64/core/xen/CMakeLists.txt

@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: Apache-2.0
+# Copyright (c) 2021 EPAM Systems
+
+# Needed to separate definitions in common Xen headers
+zephyr_compile_options($<$<COMPILE_LANGUAGE:ASM>:-D__ASSEMBLY__>)
+
+# Xen interface version used in headers for correct definition
+zephyr_compile_options(-D__XEN_INTERFACE_VERSION__=0x00040e00)
+
+zephyr_library_sources(hypercall.S)

arch/arm64/core/xen/hypercall.S

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2021 EPAM Systems
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <toolchain.h>
+#include <linker/sections.h>
+#include <xen/public/arch-arm.h>
+#include <xen/public/xen.h>
+
+#define HYPERCALL(hypercall)			\
+GTEXT(HYPERVISOR_##hypercall);			\
+SECTION_FUNC(TEXT, HYPERVISOR_##hypercall)	\
+	mov x16, #__HYPERVISOR_##hypercall;	\
+	hvc XEN_HYPERCALL_TAG;			\
+	ret;
+
+_ASM_FILE_PROLOGUE
+
+HYPERCALL(console_io);
+HYPERCALL(grant_table_op);
+HYPERCALL(sched_op);
+HYPERCALL(event_channel_op);
+HYPERCALL(hvm_op);
+HYPERCALL(memory_op);

include/arch/arm64/hypercall.h

@@ -0,0 +1,12 @@
+/*
+ * Copyright (c() 2021 EPAM Systems
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/* defined in hypercall.S by HYPERCALL(hypercall) */
+int HYPERVISOR_console_io(int op, int cnt, char *str);
+int HYPERVISOR_sched_op(int op, void *param);
+int HYPERVISOR_event_channel_op(int op, void *param);
+int HYPERVISOR_hvm_op(int op, void *param);
+int HYPERVISOR_memory_op(int op, void *param);