Add new ports: i386-xen and x86_64-xen. This allows running GRUB in

XEN PV environment and load kernels.

grub-core/lib/xen/datetime.c

@@ -0,0 +1,40 @@
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2011  Free Software Foundation, Inc.
+ *
+ *  GRUB is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/datetime.h>
+#include <grub/dl.h>
+#include <grub/misc.h>
+#include <grub/xen.h>
+
+GRUB_MOD_LICENSE ("GPLv3+");
+
+grub_err_t
+grub_get_datetime (struct grub_datetime *datetime)
+{
+  long long nix;
+  nix = (grub_xen_shared_info->wc_sec
+	 + grub_divmod64 (grub_xen_shared_info->vcpu_info[0].time.system_time, 1000000000, 0));
+  grub_unixtime2datetime (nix, datetime);
+  return GRUB_ERR_NONE;
+}
+
+grub_err_t
+grub_set_datetime (struct grub_datetime *datetime __attribute__ ((unused)))
+{
+  return grub_error (GRUB_ERR_IO, "setting time isn't supported");
+}