x86: Add relocation and link script for a 64-bit EFI application
Add a linker script and relocation code for building 64-bit EFI
applications. This can be used for the EFI stub.
Signed-off-by: Simon Glass <sjg@chromium.org>
Improvements to how the payload is built:
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/arch/x86/lib/efi/reloc_x86_64.c b/arch/x86/lib/efi/reloc_x86_64.c
new file mode 100644
index 0000000..5f71f2a
--- /dev/null
+++ b/arch/x86/lib/efi/reloc_x86_64.c
@@ -0,0 +1,66 @@
+/*
+ * reloc_x86_64.c - position independent x86_64 ELF shared object relocator
+ * Copyright (C) 1999 Hewlett-Packard Co.
+ * Contributed by David Mosberger <davidm@hpl.hp.com>.
+ * Copyright (C) 2005 Intel Co.
+ * Contributed by Fenghua Yu <fenghua.yu@intel.com>.
+ *
+ * All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <common.h>
+#include <efi.h>
+#include <elf.h>
+#include <asm/elf.h>
+
+efi_status_t _relocate(long ldbase, Elf64_Dyn *dyn, efi_handle_t image,
+ struct efi_system_table *systab)
+{
+ long relsz = 0, relent = 0;
+ Elf64_Rel *rel = 0;
+ unsigned long *addr;
+ int i;
+
+ for (i = 0; dyn[i].d_tag != DT_NULL; ++i) {
+ switch (dyn[i].d_tag) {
+ case DT_RELA:
+ rel = (Elf64_Rel *)
+ ((unsigned long)dyn[i].d_un.d_ptr + ldbase);
+ break;
+ case DT_RELASZ:
+ relsz = dyn[i].d_un.d_val;
+ break;
+ case DT_RELAENT:
+ relent = dyn[i].d_un.d_val;
+ break;
+ default:
+ break;
+ }
+ }
+
+ if (!rel && relent == 0)
+ return EFI_SUCCESS;
+
+ if (!rel || relent == 0)
+ return EFI_LOAD_ERROR;
+
+ while (relsz > 0) {
+ /* apply the relocs */
+ switch (ELF64_R_TYPE(rel->r_info)) {
+ case R_X86_64_NONE:
+ break;
+ case R_X86_64_RELATIVE:
+ addr = (unsigned long *)(ldbase + rel->r_offset);
+ *addr += ldbase;
+ break;
+ default:
+ break;
+ }
+ rel = (Elf64_Rel *)((char *)rel + relent);
+ relsz -= relent;
+ }
+
+ return EFI_SUCCESS;
+}