v4.19.13 snapshot.
diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c
new file mode 100644
index 0000000..a00934d
--- /dev/null
+++ b/drivers/firmware/efi/arm-runtime.c
@@ -0,0 +1,177 @@
+/*
+ * Extensible Firmware Interface
+ *
+ * Based on Extensible Firmware Interface Specification version 2.4
+ *
+ * Copyright (C) 2013, 2014 Linaro Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/dmi.h>
+#include <linux/efi.h>
+#include <linux/io.h>
+#include <linux/memblock.h>
+#include <linux/mm_types.h>
+#include <linux/preempt.h>
+#include <linux/rbtree.h>
+#include <linux/rwsem.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include <asm/cacheflush.h>
+#include <asm/efi.h>
+#include <asm/mmu.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+
+extern u64 efi_system_table;
+
+#ifdef CONFIG_ARM64_PTDUMP_DEBUGFS
+#include <asm/ptdump.h>
+
+static struct ptdump_info efi_ptdump_info = {
+ .mm = &efi_mm,
+ .markers = (struct addr_marker[]){
+ { 0, "UEFI runtime start" },
+ { TASK_SIZE_64, "UEFI runtime end" }
+ },
+ .base_addr = 0,
+};
+
+static int __init ptdump_init(void)
+{
+ if (!efi_enabled(EFI_RUNTIME_SERVICES))
+ return 0;
+
+ return ptdump_debugfs_register(&efi_ptdump_info, "efi_page_tables");
+}
+device_initcall(ptdump_init);
+
+#endif
+
+static bool __init efi_virtmap_init(void)
+{
+ efi_memory_desc_t *md;
+ bool systab_found;
+
+ efi_mm.pgd = pgd_alloc(&efi_mm);
+ mm_init_cpumask(&efi_mm);
+ init_new_context(NULL, &efi_mm);
+
+ systab_found = false;
+ for_each_efi_memory_desc(md) {
+ phys_addr_t phys = md->phys_addr;
+ int ret;
+
+ if (!(md->attribute & EFI_MEMORY_RUNTIME))
+ continue;
+ if (md->virt_addr == 0)
+ return false;
+
+ ret = efi_create_mapping(&efi_mm, md);
+ if (ret) {
+ pr_warn(" EFI remap %pa: failed to create mapping (%d)\n",
+ &phys, ret);
+ return false;
+ }
+ /*
+ * If this entry covers the address of the UEFI system table,
+ * calculate and record its virtual address.
+ */
+ if (efi_system_table >= phys &&
+ efi_system_table < phys + (md->num_pages * EFI_PAGE_SIZE)) {
+ efi.systab = (void *)(unsigned long)(efi_system_table -
+ phys + md->virt_addr);
+ systab_found = true;
+ }
+ }
+ if (!systab_found) {
+ pr_err("No virtual mapping found for the UEFI System Table\n");
+ return false;
+ }
+
+ if (efi_memattr_apply_permissions(&efi_mm, efi_set_mapping_permissions))
+ return false;
+
+ return true;
+}
+
+/*
+ * Enable the UEFI Runtime Services if all prerequisites are in place, i.e.,
+ * non-early mapping of the UEFI system table and virtual mappings for all
+ * EFI_MEMORY_RUNTIME regions.
+ */
+static int __init arm_enable_runtime_services(void)
+{
+ u64 mapsize;
+
+ if (!efi_enabled(EFI_BOOT)) {
+ pr_info("EFI services will not be available.\n");
+ return 0;
+ }
+
+ efi_memmap_unmap();
+
+ mapsize = efi.memmap.desc_size * efi.memmap.nr_map;
+
+ if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) {
+ pr_err("Failed to remap EFI memory map\n");
+ return 0;
+ }
+
+ if (efi_runtime_disabled()) {
+ pr_info("EFI runtime services will be disabled.\n");
+ return 0;
+ }
+
+ if (efi_enabled(EFI_RUNTIME_SERVICES)) {
+ pr_info("EFI runtime services access via paravirt.\n");
+ return 0;
+ }
+
+ pr_info("Remapping and enabling EFI services.\n");
+
+ if (!efi_virtmap_init()) {
+ pr_err("UEFI virtual mapping missing or invalid -- runtime services will not be available\n");
+ return -ENOMEM;
+ }
+
+ /* Set up runtime services function pointers */
+ efi_native_runtime_setup();
+ set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
+
+ return 0;
+}
+early_initcall(arm_enable_runtime_services);
+
+void efi_virtmap_load(void)
+{
+ preempt_disable();
+ efi_set_pgd(&efi_mm);
+}
+
+void efi_virtmap_unload(void)
+{
+ efi_set_pgd(current->active_mm);
+ preempt_enable();
+}
+
+
+static int __init arm_dmi_init(void)
+{
+ /*
+ * On arm64/ARM, DMI depends on UEFI, and dmi_scan_machine() needs to
+ * be called early because dmi_id_init(), which is an arch_initcall
+ * itself, depends on dmi_scan_machine() having been called already.
+ */
+ dmi_scan_machine();
+ if (dmi_available)
+ dmi_set_dump_stack_arch_desc();
+ return 0;
+}
+core_initcall(arm_dmi_init);