efi: arm: Add EFI app support

Add support for EFI apps on ARM. This includes start-up and relocation
code, plus a link script and some compiler setting changes.

Signed-off-by: Simon Glass <sjg@chromium.org>
[agraf: Remove whitespace change, add kconfig dep]
Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 66 insertions, 0 deletions

diff --git a/arch/arm/lib/reloc_arm_efi.c b/arch/arm/lib/reloc_arm_efi.c
new file mode 100644
index 0000000..d2f96ee
--- /dev/null
+++ b/arch/arm/lib/reloc_arm_efi.c
@@ -0,0 +1,66 @@
+/*
+ * reloc_arm.c - position-independent ARM ELF shared object relocator
+ *
+ * Copyright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
+ * Copyright (C) 1999 Hewlett-Packard Co.
+ * Contributed by David Mosberger <davidm@hpl.hp.com>.
+ *
+ * All rights reserved.
+ *
+ * SPDX-License-Identifier:	BSD-3-Clause
+ *
+ * This file is taken and modified from the gnu-efi project.
+ */
+
+#include <efi.h>
+#include <elf.h>
+
+efi_status_t _relocate(long ldbase, Elf32_Dyn *dyn, efi_handle_t image,
+		       struct efi_system_table *systab)
+{
+	long relsz = 0, relent = 0;
+	Elf32_Rel *rel = 0;
+	ulong *addr;
+	int i;
+
+	for (i = 0; dyn[i].d_tag != DT_NULL; ++i) {
+		switch (dyn[i].d_tag) {
+		case DT_REL:
+			rel = (Elf32_Rel *)((ulong)dyn[i].d_un.d_ptr
+					+ ldbase);
+			break;
+		case DT_RELSZ:
+			relsz = dyn[i].d_un.d_val;
+			break;
+		case DT_RELENT:
+			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 (ELF32_R_TYPE(rel->r_info)) {
+		case R_ARM_NONE:
+			break;
+		case R_ARM_RELATIVE:
+			addr = (ulong *)(ldbase + rel->r_offset);
+			*addr += ldbase;
+			break;
+		default:
+			break;
+		}
+		rel = (Elf32_Rel *)((char *)rel + relent);
+		relsz -= relent;
+	}
+
+	return EFI_SUCCESS;
+}