board: xen: De-initialize before jumping to Linux

Free resources used by Xen board before jumping to Linux kernel.
Signed-off-by: NOleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Signed-off-by: NAnastasiia Lukianenko <anastasiia_lukianenko@epam.com>
Reviewed-by: NSimon Glass <sjg@chromium.org>

board/xen/xenguest_arm64/xenguest_arm64.c

@@ -12,6 +12,7 @@
 #include <dm.h>
 #include <errno.h>
 #include <malloc.h>
+#include <xen.h>
 
 #include <asm/io.h>
 #include <asm/armv8/mmu.h>
@@ -194,3 +195,8 @@ int print_cpuinfo(void)
 	return 0;
 }
 
+void board_cleanup_before_linux(void)
+{
+	xen_fini();
+}
+

drivers/xen/hypervisor.c

@@ -242,3 +242,11 @@ void xen_init(void)
 	init_gnttab();
 }
 
+void xen_fini(void)
+{
+	debug("%s\n", __func__);
+
+	fini_gnttab();
+	fini_xenbus();
+	fini_events();
+}

include/xen.h

@@ -13,4 +13,12 @@
  */
 void xen_init(void);
 
+/**
+ * xen_fini() - Board cleanup before Linux kernel start
+ *
+ * Unmap Xen memory pages the specified guest's pseudophysical
+ * address space and unbind all event channels.
+ */
+void xen_fini(void);
+
 #endif /* __XEN_H__ */