I'm working on a simple application that will be running on a Intel Galileo's board as UEFI app. I've started with a "Hello, World" app and tested it under qemu-system-i386
and it works well. Then, I've run it under Galileo EFI Shell and it stuck (nothing happend and never returned anything - like a never-ending loop). I know that Intel Galileo's Quark processor is a i586 architecture. It shouldn't be a problem to run application compiled for i386 under i586, due to the backward compatibility, am I right? Or am I missing something?
I'm using Ubuntu 14.04 (32-bit) for development with GCC 5.4.0 (default). Also, I'm using gnu-efi in version 3.0.4.
Should I build a cross-compiler? Will it resolve all of my problems? Is it necessary?
Here is a sample code:
#include <efi.h>
#include <efilib.h>
EFI_STATUS EFIAPI efi_main(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable) {
InitializeLib(ImageHandle, SystemTable);
Print(L"Hello, World!\n");
return EFI_SUCCESS;
}
Here is my Makefile:
ARCH = ia32
OBJS = src/main.o
HEADERS =
TARGET = build/main.efi
EFIINC = lib/gnu-efi/inc
EFIINCS = -I$(EFIINC) -I$(EFIINC)/$(ARCH) -I$(EFIINC)/protocol
LIB = lib/gnu-efi/$(ARCH)/lib
EFILIB = lib/gnu-efi/gnuefi
EFI_CRT_OBJS = $(EFILIB)/crt0-efi-$(ARCH).o
EFI_LDS = $(EFILIB)/elf_$(ARCH)_efi.lds
CFLAGS = $(EFIINCS) -ffreestanding -fno-stack-protector -fpic -fshort-wchar -mno-red-zone -Wall -masm=intel
LDFLAGS = -nostdlib -znocombreloc -T $(EFI_LDS) -shared -Bsymbolic -L $(EFILIB) -L $(LIB) $(EFI_CRT_OBJS)
all: $(TARGET)
build: $(TARGET)
src/%.so: $(OBJS) $(HEADERS)
ld $(LDFLAGS) $(OBJS) -o $@ -l:libefi.a -l:libgnuefi.a
build/%.efi: src/%.so
objcopy -j .text -j .sdata -j .data -j .dynamic \
-j .dynsym -j .rel -j .rela -j .reloc \
--target=efi-app-$(ARCH) $^ $@
run:
qemu-system-i386 bin/OVMF.fd -hda fat:build
.PHONY: all build run