u-boot/arch/x86/config.mk
Simon Glass 476476e73b efi: Add support for loading U-Boot through an EFI stub
It is useful to be able to load U-Boot onto a board even if is it already
running EFI. This can allow access to the U-Boot command interface, flexible
booting options and easier development.

The easiest way to do this is to build U-Boot as a binary blob and have an
EFI stub copy it into RAM. Add support for this feature, targeting 32-bit
initially.

Also add a way to detect when U-Boot has been loaded via a stub. This goes
in common.h since it needs to be widely available so that we avoid redoing
initialisation that should be skipped.

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>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
2015-08-05 08:44:06 -06:00

57 lines
1.5 KiB
Makefile

#
# (C) Copyright 2000-2002
# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
#
# SPDX-License-Identifier: GPL-2.0+
#
CONFIG_STANDALONE_LOAD_ADDR ?= 0x40000
PLATFORM_CPPFLAGS += -fno-strict-aliasing
PLATFORM_CPPFLAGS += -fomit-frame-pointer
PF_CPPFLAGS_X86 := $(call cc-option, -fno-toplevel-reorder, \
$(call cc-option, -fno-unit-at-a-time)) \
$(call cc-option, -mpreferred-stack-boundary=2)
PLATFORM_CPPFLAGS += $(PF_CPPFLAGS_X86)
PLATFORM_CPPFLAGS += -fno-dwarf2-cfi-asm
PLATFORM_CPPFLAGS += -march=i386 -m32
PLATFORM_RELFLAGS += -ffunction-sections -fvisibility=hidden
PLATFORM_LDFLAGS += -Bsymbolic -Bsymbolic-functions -m elf_i386
LDFLAGS_FINAL += --wrap=__divdi3 --wrap=__udivdi3
LDFLAGS_FINAL += --wrap=__moddi3 --wrap=__umoddi3
# This is used in the top-level Makefile which does not include
# PLATFORM_LDFLAGS
LDFLAGS_EFI_PAYLOAD := -Bsymbolic -Bsymbolic-functions -shared --no-undefined
OBJCOPYFLAGS_EFI := -j .text -j .sdata -j .data -j .dynamic -j .dynsym \
-j .rel -j .rela -j .reloc
CFLAGS_NON_EFI := -mregparm=3
CFLAGS_EFI := -fpic -fshort-wchar
EFIARCH = ia32
EFIPAYLOAD_BFDTARGET = elf32-i386
EFIPAYLOAD_BFDARCH = i386
LDSCRIPT_EFI := $(srctree)/$(CPUDIR)/efi/elf_$(EFIARCH)_efi.lds
OBJCOPYFLAGS_EFI += --target=efi-app-$(EFIARCH)
ifeq ($(CONFIG_EFI_APP),y)
PLATFORM_CPPFLAGS += $(CFLAGS_EFI)
LDFLAGS_FINAL += -znocombreloc -shared
LDSCRIPT := $(LDSCRIPT_EFI)
else
PLATFORM_CPPFLAGS += $(CFLAGS_NON_EFI)
PLATFORM_LDFLAGS += --emit-relocs
LDFLAGS_FINAL += --gc-sections -pie
endif