+/*
+ * We can't ioremap data in EFI boot services RAM, because we've already mapped
+ * it as RAM. So, look it up in the existing EFI memory map instead. Only
+ * callable after efi_enter_virtual_mode and before efi_free_boot_services.
+ */
+void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
+{
+ struct efi_memory_map *map;
+ void *p;
+ map = efi.memmap;
+ if (!map)
+ return NULL;
+ if (WARN_ON(!map->map))
+ return NULL;
+ for (p = map->map; p < map->map_end; p += map->desc_size) {
+ efi_memory_desc_t *md = p;
+ u64 size = md->num_pages << EFI_PAGE_SHIFT;
+ u64 end = md->phys_addr + size;
+ if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
+ md->type != EFI_BOOT_SERVICES_CODE &&
+ md->type != EFI_BOOT_SERVICES_DATA)
+ continue;
+ if (!md->virt_addr)
+ continue;
+ if (phys_addr >= md->phys_addr && phys_addr < end) {
+ phys_addr += md->virt_addr - md->phys_addr;
+ return (__force void __iomem *)(unsigned long)phys_addr;
+ }
+ }
+ return NULL;
+}
+