[U-Boot] [PATCH v4 08/14] efi: arm: Add EFI app support
Simon Glass
sjg at chromium.org
Mon Nov 7 16:47:10 CET 2016
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 at chromium.org>
---
Changes in v4:
- Add new patch to add EFI app support
Changes in v3: None
Changes in v2: None
arch/arm/config.mk | 7 +++
arch/arm/lib/Makefile | 10 ++++
arch/arm/lib/crt0_arm_efi.S | 138 +++++++++++++++++++++++++++++++++++++++++++
arch/arm/lib/elf_arm_efi.lds | 70 ++++++++++++++++++++++
arch/arm/lib/reloc_arm_efi.c | 66 +++++++++++++++++++++
lib/efi_loader/Kconfig | 2 +-
6 files changed, 292 insertions(+), 1 deletion(-)
create mode 100644 arch/arm/lib/crt0_arm_efi.S
create mode 100644 arch/arm/lib/elf_arm_efi.lds
create mode 100644 arch/arm/lib/reloc_arm_efi.c
diff --git a/arch/arm/config.mk b/arch/arm/config.mk
index 542b897..27914a9 100644
--- a/arch/arm/config.mk
+++ b/arch/arm/config.mk
@@ -13,6 +13,9 @@ CONFIG_STANDALONE_LOAD_ADDR = 0xc100000
endif
endif
+CFLAGS_NON_EFI := -fno-pic -ffixed-r9 -ffunction-sections -fdata-sections
+CFLAGS_EFI := -fpic -fshort-wchar
+
LDFLAGS_FINAL += --gc-sections
PLATFORM_RELFLAGS += -ffunction-sections -fdata-sections \
-fno-common -ffixed-r9
@@ -148,3 +151,7 @@ ifneq ($(CONFIG_VF610),)
ALL-y += u-boot.vyb
endif
endif
+
+EFI_LDS := elf_arm_efi.lds
+EFI_CRT0 := crt0_arm_efi.o
+EFI_RELOC := reloc_arm_efi.o
diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
index caa62c6..a812306 100644
--- a/arch/arm/lib/Makefile
+++ b/arch/arm/lib/Makefile
@@ -92,3 +92,13 @@ AFLAGS_memset.o := -DMEMSET_NO_THUMB_BUILD
AFLAGS_memcpy.o := -DMEMCPY_NO_THUMB_BUILD
endif
endif
+
+# For building EFI apps
+CFLAGS_$(EFI_CRT0) := $(CFLAGS_EFI)
+CFLAGS_REMOVE_$(EFI_CRT0) := $(CFLAGS_NON_EFI)
+
+CFLAGS_$(EFI_RELOC) := $(CFLAGS_EFI)
+CFLAGS_REMOVE_$(EFI_RELOC) := $(CFLAGS_NON_EFI)
+
+extra-$(CONFIG_CMD_BOOTEFI_HELLO) += $(EFI_CRT0) $(EFI_RELOC)
+extra-$(CONFIG_EFI) += $(EFI_CRT0) $(EFI_RELOC)
diff --git a/arch/arm/lib/crt0_arm_efi.S b/arch/arm/lib/crt0_arm_efi.S
new file mode 100644
index 0000000..967c885
--- /dev/null
+++ b/arch/arm/lib/crt0_arm_efi.S
@@ -0,0 +1,138 @@
+/*
+ * crt0-efi-arm.S - PE/COFF header for ARM EFI applications
+ *
+ * Copright (C) 2014 Linaro Ltd. <ard.biesheuvel at linaro.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+ BSD-2-Clause
+ *
+ * This file is taken and modified from the gnu-efi project.
+ */
+
+ .section .text.head
+
+ /*
+ * Magic "MZ" signature for PE/COFF
+ */
+ .globl image_base
+image_base:
+ .ascii "MZ"
+ .skip 58 /* 'MZ' + pad + offset == 64 */
+ .long pe_header - image_base /* Offset to the PE header */
+pe_header:
+ .ascii "PE"
+ .short 0
+coff_header:
+ .short 0x1c2 /* Mixed ARM/Thumb */
+ .short 2 /* nr_sections */
+ .long 0 /* TimeDateStamp */
+ .long 0 /* PointerToSymbolTable */
+ .long 1 /* NumberOfSymbols */
+ .short section_table - optional_header /* SizeOfOptionalHeader */
+ /*
+ * Characteristics: IMAGE_FILE_32BIT_MACHINE |
+ * IMAGE_FILE_DEBUG_STRIPPED | IMAGE_FILE_EXECUTABLE_IMAGE |
+ * IMAGE_FILE_LINE_NUMS_STRIPPED
+ */
+ .short 0x306
+optional_header:
+ .short 0x10b /* PE32+ format */
+ .byte 0x02 /* MajorLinkerVersion */
+ .byte 0x14 /* MinorLinkerVersion */
+ .long _edata - _start /* SizeOfCode */
+ .long 0 /* SizeOfInitializedData */
+ .long 0 /* SizeOfUninitializedData */
+ .long _start - image_base /* AddressOfEntryPoint */
+ .long _start - image_base /* BaseOfCode */
+ .long 0 /* BaseOfData */
+
+extra_header_fields:
+ .long 0 /* image_base */
+ .long 0x20 /* SectionAlignment */
+ .long 0x8 /* FileAlignment */
+ .short 0 /* MajorOperatingSystemVersion */
+ .short 0 /* MinorOperatingSystemVersion */
+ .short 0 /* MajorImageVersion */
+ .short 0 /* MinorImageVersion */
+ .short 0 /* MajorSubsystemVersion */
+ .short 0 /* MinorSubsystemVersion */
+ .long 0 /* Win32VersionValue */
+
+ .long _edata - image_base /* SizeOfImage */
+
+ /*
+ * Everything before the kernel image is considered part of the header
+ */
+ .long _start - image_base /* SizeOfHeaders */
+ .long 0 /* CheckSum */
+ .short EFI_SUBSYSTEM /* Subsystem */
+ .short 0 /* DllCharacteristics */
+ .long 0 /* SizeOfStackReserve */
+ .long 0 /* SizeOfStackCommit */
+ .long 0 /* SizeOfHeapReserve */
+ .long 0 /* SizeOfHeapCommit */
+ .long 0 /* LoaderFlags */
+ .long 0x6 /* NumberOfRvaAndSizes */
+
+ .quad 0 /* ExportTable */
+ .quad 0 /* ImportTable */
+ .quad 0 /* ResourceTable */
+ .quad 0 /* ExceptionTable */
+ .quad 0 /* CertificationTable */
+ .quad 0 /* BaseRelocationTable */
+
+section_table:
+
+ /*
+ * The EFI application loader requires a relocation section
+ * because EFI applications must be relocatable. This is a
+ * dummy section as far as we are concerned.
+ */
+ .ascii ".reloc"
+ .byte 0
+ .byte 0 /* end of 0 padding of section name */
+ .long 0
+ .long 0
+ .long 0 /* SizeOfRawData */
+ .long 0 /* PointerToRawData */
+ .long 0 /* PointerToRelocations */
+ .long 0 /* PointerToLineNumbers */
+ .short 0 /* NumberOfRelocations */
+ .short 0 /* NumberOfLineNumbers */
+ .long 0x42100040 /* Characteristics (section flags) */
+
+ .ascii ".text"
+ .byte 0
+ .byte 0
+ .byte 0 /* end of 0 padding of section name */
+ .long _edata - _start /* VirtualSize */
+ .long _start - image_base /* VirtualAddress */
+ .long _edata - _start /* SizeOfRawData */
+ .long _start - image_base /* PointerToRawData */
+
+ .long 0 /* PointerToRelocations (0 for executables) */
+ .long 0 /* PointerToLineNumbers (0 for executables) */
+ .short 0 /* NumberOfRelocations (0 for executables) */
+ .short 0 /* NumberOfLineNumbers (0 for executables) */
+ .long 0xe0500020 /* Characteristics (section flags) */
+
+_start:
+ stmfd sp!, {r0-r2, lr}
+
+ mov r2, r0
+ mov r3, r1
+ adr r1, .L_DYNAMIC
+ ldr r0, [r1]
+ add r1, r0, r1
+ adr r0, image_base
+ bl _relocate
+ teq r0, #0
+ bne 0f
+
+ ldmfd sp, {r0-r1}
+ bl efi_main
+
+0: add sp, sp, #12
+ ldr pc, [sp], #4
+
+.L_DYNAMIC:
+ .word _DYNAMIC - .
diff --git a/arch/arm/lib/elf_arm_efi.lds b/arch/arm/lib/elf_arm_efi.lds
new file mode 100644
index 0000000..59f66a1
--- /dev/null
+++ b/arch/arm/lib/elf_arm_efi.lds
@@ -0,0 +1,70 @@
+/*
+ * U-Boot ARM EFI linker script
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Modified from elf_arm_efi.lds in gnu-efi
+ */
+
+OUTPUT_FORMAT("elf32-littlearm", "elf32-littlearm", "elf32-littlearm")
+OUTPUT_ARCH(arm)
+ENTRY(_start)
+SECTIONS
+{
+ .text 0x0 : {
+ _text = .;
+ *(.text.head)
+ *(.text)
+ *(.text.*)
+ *(.gnu.linkonce.t.*)
+ *(.srodata)
+ *(.rodata*)
+ . = ALIGN(16);
+ }
+ _etext = .;
+ _text_size = . - _text;
+ .dynamic : { *(.dynamic) }
+ .data : {
+ _data = .;
+ *(.sdata)
+ *(.data)
+ *(.data1)
+ *(.data.*)
+ *(.got.plt)
+ *(.got)
+
+ /*
+ * The EFI loader doesn't seem to like a .bss section, so we
+ * stick it all into .data:
+ */
+ . = ALIGN(16);
+ _bss = .;
+ *(.sbss)
+ *(.scommon)
+ *(.dynbss)
+ *(.bss)
+ *(.bss.*)
+ *(COMMON)
+ . = ALIGN(16);
+ _bss_end = .;
+ _edata = .;
+ }
+ .rel.dyn : { *(.rel.dyn) }
+ .rel.plt : { *(.rel.plt) }
+ .rel.got : { *(.rel.got) }
+ .rel.data : { *(.rel.data) *(.rel.data*) }
+ _data_size = . - _etext;
+
+ . = ALIGN(4096);
+ .dynsym : { *(.dynsym) }
+ . = ALIGN(4096);
+ .dynstr : { *(.dynstr) }
+ . = ALIGN(4096);
+ .note.gnu.build-id : { *(.note.gnu.build-id) }
+ /DISCARD/ : {
+ *(.rel.reloc)
+ *(.eh_frame)
+ *(.note.GNU-stack)
+ }
+ .comment 0 : { *(.comment) }
+}
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 at linaro.org>
+ * Copyright (C) 1999 Hewlett-Packard Co.
+ * Contributed by David Mosberger <davidm at 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;
+}
diff --git a/lib/efi_loader/Kconfig b/lib/efi_loader/Kconfig
index 37a0dd6..48563aa 100644
--- a/lib/efi_loader/Kconfig
+++ b/lib/efi_loader/Kconfig
@@ -1,6 +1,6 @@
config EFI_LOADER
bool "Support running EFI Applications in U-Boot"
- depends on (ARM64 || ARM) && OF_LIBFDT
+ depends on (ARM64 || ARM) && OF_LIBFDT
default y
help
Select this option if you want to run EFI applications (like grub2)
--
2.8.0.rc3.226.g39d4020
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