[U-Boot] [PATCH 8/8] mips: bmips: add support for raw .elf images

[Álvaro Fernández Rojas]

Hi,

El 15/04/2017 a las 21:14, Álvaro Fernández Rojas escribió:
> Hi,
> 
> El 15/04/2017 a las 20:54, Daniel Schwierzeck escribió:
>>
>>
>> Am 15.04.2017 um 20:10 schrieb Álvaro Fernández Rojas:
>>> Hi,
>>>
>>> El 15/04/2017 a las 19:19, Álvaro Fernández Rojas escribió:
>>>>
>>>>
>>>> El 14/04/2017 a las 21:05, Daniel Schwierzeck escribió:
>>>>>
>>>>>
>>>>> Am 13.04.2017 um 17:52 schrieb Álvaro Fernández Rojas:
>>>>>> CFE supports loading .elf images instead of raw binaries.
>>>>>>
>>>>>> Signed-off-by: Álvaro Fernández Rojas <noltari at gmail.com>
>>>>>> ---
>>>>>>  Makefile                     | 22 ++++++++++++++++++++++
>>>>>>  arch/mips/cpu/u-boot-elf.lds | 10 ++++++++++
>>>>>>  2 files changed, 32 insertions(+)
>>>>>>  create mode 100644 arch/mips/cpu/u-boot-elf.lds
>>>>>>
>>>>>> diff --git a/Makefile b/Makefile
>>>>>> index 09b597d..667b5f2 100644
>>>>>> --- a/Makefile
>>>>>> +++ b/Makefile
>>>>>> @@ -568,6 +568,15 @@ ifndef LDSCRIPT
>>>>>>  	endif
>>>>>>  endif
>>>>>>  
>>>>>> +ifndef LDSCRIPT_ELF
>>>>>> +	ifeq ($(wildcard $(LDSCRIPT_ELF)),)
>>>>>> +		LDSCRIPT_ELF := $(srctree)/$(CPUDIR)/u-boot-elf.lds
>>>>>> +	endif
>>>>>> +	ifeq ($(wildcard $(LDSCRIPT_ELF)),)
>>>>>> +		LDSCRIPT_ELF := $(srctree)/arch/$(ARCH)/cpu/u-boot-elf.lds
>>>>>> +	endif
>>>>>> +endif
>>>>>
>>>>> could you try to build the ELF binary without a custom linker script? I
>>>>> think the built-in one should work too.
>>>>>
>>>>>> +
>>>>>>  else
>>>>>>  # Dummy target needed, because used as prerequisite
>>>>>>  include/config/auto.conf: ;
>>>>>> @@ -786,6 +795,7 @@ ifneq ($(CONFIG_SPL_TARGET),)
>>>>>>  ALL-$(CONFIG_SPL) += $(CONFIG_SPL_TARGET:"%"=%)
>>>>>>  endif
>>>>>>  ALL-$(CONFIG_REMAKE_ELF) += u-boot.elf
>>>>>> +ALL-$(CONFIG_ARCH_BMIPS) += u-boot-bmips.elf
>>>>>>  ALL-$(CONFIG_EFI_APP) += u-boot-app.efi
>>>>>>  ALL-$(CONFIG_EFI_STUB) += u-boot-payload.efi
>>>>>>  
>>>>>> @@ -1192,6 +1202,15 @@ u-boot.elf: u-boot.bin
>>>>>>  		--defsym=_start=$(CONFIG_SYS_TEXT_BASE) \
>>>>>>  		-Ttext=$(CONFIG_SYS_TEXT_BASE)
>>>>>>  
>>>>>> +# Rules to link u-boot-bmips
>>>>>> +quiet_cmd_u-boot-bmips ?= LD      $@
>>>>>> +	cmd_u-boot-bmips ?= $(LD) -e startup -T u-boot-elf.lds \
>>>>>> +	-Ttext $(CONFIG_SYS_TEXT_BASE) -o $@ u-boot-bmips.o
>>>>>> +
>>>>>> +u-boot-bmips.elf: u-boot.bin u-boot-elf.lds
>>>>>> +	$(Q)$(LD) -r -b binary --oformat elf32-tradbigmips -o u-boot-bmips.o $<
>>>>>> +	$(call if_changed,u-boot-bmips)
>>>>>
>>>>> could you try to generate the ELF binary like in the existing rule
>>>>> above? If that works, we could refactor the generic rule to remove the
>>>>> hard-coded aarch64 flags. If not, move this code and the
>>>>> "ALL-$(CONFIG_ARCH_BMIPS) += u-boot-bmips.elf" to arch/mips/Makefile
>>>> Sure, I will try and see if it works.
>>> It works, but it has to be changed:
>>> u-boot.elf: u-boot.bin
>>> 	@$(OBJCOPY) -B mips -I binary -O elf32-tradbigmips \
>>> 		$< u-boot-elf.o
>>> 	@$(LD) u-boot-elf.o -o $@ \
>>> 		--defsym=__start=$(CONFIG_SYS_TEXT_BASE) \
>>> 		-Ttext=$(CONFIG_SYS_TEXT_BASE)
>>> Changes:
>>> 1) __start symbol instead of _start
>>> 2) mips instead of aarch64
>>> 3) elf32-tradbigmips instead of elf64-littleaarch64
>>
>> 2) and 3) are expected, that's what could be fixed with a small
>> refactoring. But why --defsym=__start? The U-Boot entry point is _start.
> --defsym=_start throws the following error:
> mips-openwrt-linux-ld.bfd: warning: cannot find entry symbol __start; defaulting to 0000000080010000
> However, --defsym=__start throws no errors...
Is this reasonable?
https://gist.github.com/Noltari/d259af2709ac4cb9e091f291d7cf5e6f

> 
>>
>>>
>>>>
>>>>>
>>>>> Also don't forget to add new binaries to .gitignore and the Makefile
>>>>> clean targets.
>>>> Right, my fault :).
>>>>
>>>>>
>>>>>> +
>>>>>>  # Rule to link u-boot
>>>>>>  # May be overridden by arch/$(ARCH)/config.mk
>>>>>>  quiet_cmd_u-boot__ ?= LD      $@
>>>>>> @@ -1340,6 +1359,9 @@ cmd_cpp_lds = $(CPP) -Wp,-MD,$(depfile) $(cpp_flags) $(LDPPFLAGS) \
>>>>>>  u-boot.lds: $(LDSCRIPT) prepare FORCE
>>>>>>  	$(call if_changed_dep,cpp_lds)
>>>>>>  
>>>>>> +u-boot-elf.lds: $(LDSCRIPT_ELF) prepare
>>>>>> +	$(call if_changed_dep,cpp_lds)
>>>>>> +
>>>>>>  spl/u-boot-spl.bin: spl/u-boot-spl
>>>>>>  	@:
>>>>>>  spl/u-boot-spl: tools prepare \
>>>>>> diff --git a/arch/mips/cpu/u-boot-elf.lds b/arch/mips/cpu/u-boot-elf.lds
>>>>>> new file mode 100644
>>>>>> index 0000000..db0bb46
>>>>>> --- /dev/null
>>>>>> +++ b/arch/mips/cpu/u-boot-elf.lds
>>>>>> @@ -0,0 +1,10 @@
>>>>>> +OUTPUT_ARCH(mips)
>>>>>> +SECTIONS {
>>>>>> +	.text : {
>>>>>> +		startup = .;
>>>>>> +		*(.text)
>>>>>> +		*(.text.*)
>>>>>> +		*(.data)
>>>>>> +		*(.data.*)
>>>>>> +	}
>>>>>> +}
>>>>>>
>>>>>
>>