arm/xen: Use xen_xlate_map_ballooned_pages to setup grant table

Use xen_xlate_map_ballooned_pages to setup grant table. Then it doesn't
rely on DT or ACPI to pass the start address and size of grant table.
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Julien Grall <julien.grall@arm.com>
Tested-by: Julien Grall <julien.grall@arm.com>

arch/arm/xen/enlighten.c

@@ -282,18 +282,10 @@ static int __init xen_guest_init(void)
 {
 	struct xen_add_to_physmap xatp;
 	struct shared_info *shared_info_page = NULL;
-	struct resource res;
-	phys_addr_t grant_frames;
 
 	if (!xen_domain())
 		return 0;
 
-	if (of_address_to_resource(xen_node, GRANT_TABLE_PHYSADDR, &res)) {
-		pr_err("Xen grant table base address not found\n");
-		return -ENODEV;
-	}
-	grant_frames = res.start;
-
 	xen_events_irq = irq_of_parse_and_map(xen_node, 0);
 	if (!xen_events_irq) {
 		pr_err("Xen event channel interrupt not found\n");
@@ -328,7 +320,10 @@ static int __init xen_guest_init(void)
 	if (xen_vcpu_info == NULL)
 		return -ENOMEM;
 
-	if (gnttab_setup_auto_xlat_frames(grant_frames)) {
+	xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames();
+	if (xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn,
+					  &xen_auto_xlat_grant_frames.vaddr,
+					  xen_auto_xlat_grant_frames.count)) {
 		free_percpu(xen_vcpu_info);
 		return -ENOMEM;
 	}