Index: sys/arm64/arm64/machdep.c
===================================================================
--- sys/arm64/arm64/machdep.c
+++ sys/arm64/arm64/machdep.c
@@ -105,6 +105,16 @@
 
 enum arm64_bus arm64_bus_method = ARM64_BUS_NONE;
 
+#ifdef XENHVM
+#include <xen/xen-os.h>
+#include <xen/features.h>
+
+static start_info_t _xen_start_info;
+start_info_t *HYPERVISOR_start_info = &_xen_start_info;
+
+enum xen_domain_type xen_domain_type = XEN_NATIVE;
+#endif
+
 struct pcpu __pcpu[MAXCPU];
 
 static struct trapframe proc0_tf;
@@ -1235,6 +1245,31 @@
 	return (VM_MEMATTR_DEVICE);
 }
 
+#ifdef XENHVM
+static void
+xen_early_init(void)
+{
+	phandle_t root;
+
+	if ((root = OF_finddevice("/")) == 0)
+		return;
+	/*
+	 * The device tree contains a node with the compatible string "xen,xen"
+	 * when the OS will run on top of Xen.
+	 */
+	if (fdt_depth_search_compatible(root, "xen,xen", 0) == 0)
+		return;
+
+	xen_domain_type = XEN_HVM_DOMAIN;
+	setup_xen_features();
+
+	if (xen_feature(XENFEAT_dom0))
+		HYPERVISOR_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
+	else
+		HYPERVISOR_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);
+}
+#endif
+
 void
 initarm(struct arm64_bootparams *abp)
 {
@@ -1267,6 +1302,14 @@
 	link_elf_ireloc(kmdp);
 	try_load_dtb(kmdp);
 
+#ifdef XENHVM
+	/*
+	 * We need to know early if FreeBSD is running on top of Xen.
+	 * Therefore we can get an early console working
+	 */
+	xen_early_init();
+#endif
+
 	efi_systbl_phys = MD_FETCH(kmdp, MODINFOMD_FW_HANDLE, vm_paddr_t);
 
 	/* Load the physical memory ranges */