[U-Boot] [PATCH v2 4/8] x86: Tidy up selection of building the EFI stub

[Bin Meng]

Hi Simon,

On Tue, Sep 27, 2016 at 8:35 AM, Simon Glass <sjg at chromium.org> wrote:
> Hi Bin,
>
> On 26 September 2016 at 02:50, Bin Meng <bmeng.cn at gmail.com> wrote:
>> Hi Simon,
>>
>> On Mon, Sep 26, 2016 at 5:27 AM, Simon Glass <sjg at chromium.org> wrote:
>>> At present we use a CONFIG option in efi.h to determine whether we are
>>> building the EFI stub or not. This means that the same header cannot be
>>> used for EFI_LOADER support. The CONFIG option will be enabled for the
>>> whole build, even when not building the stub.
>>>
>>> Use a different define instead, set up just for the files that make up the
>>> stub.
>>>
>>> Signed-off-by: Simon Glass <sjg at chromium.org>
>>> ---
>>>
>>> Changes in v2:
>>> - Add new patch to tidy up selection of building the EFI stub
>>>
>>>  include/efi.h    | 7 +++++--
>>>  lib/efi/Makefile | 4 ++--
>>>  2 files changed, 7 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/include/efi.h b/include/efi.h
>>> index d07187c..3d58780 100644
>>> --- a/include/efi.h
>>> +++ b/include/efi.h
>>> @@ -30,8 +30,11 @@ struct efi_device_path;
>>>
>>>  #define EFI_BITS_PER_LONG      BITS_PER_LONG
>>>
>>> -/* With 64-bit EFI stub, EFI_BITS_PER_LONG has to be 64 */
>>> -#ifdef CONFIG_EFI_STUB_64BIT
>>> +/*
>>> + * With 64-bit EFI stub, EFI_BITS_PER_LONG has to be 64. EFI_STUB is set
>>> + * in lib/efi/Makefile, when building the stub.
>>> + */
>>> +#if defined(CONFIG_EFI_STUB_64BIT) && defined(EFI_STUB)
>>
>> I don't understand why this is needed?
>
> If building the 64-bit EFI stub, we need to use 64-bit ints for the
> stub, but 32-bits for the rest of U-Boot. So this header gets used
> both ways.
>

For 32-bit EFI stub or U-Boot itself, EFI_BITS_PER_LONG is defined as
BITS_PER_LONG which is 32.

>>
>>>  #undef EFI_BITS_PER_LONG
>>>  #define EFI_BITS_PER_LONG      64
>>>  #endif
>>> diff --git a/lib/efi/Makefile b/lib/efi/Makefile
>>> index e32dc14..9449600 100644
>>> --- a/lib/efi/Makefile
>>> +++ b/lib/efi/Makefile
>>> @@ -9,9 +9,9 @@ obj-$(CONFIG_EFI_STUB) += efi_info.o
>>>
>>>  CFLAGS_REMOVE_efi_stub.o := -mregparm=3 \
>>>         $(if $(CONFIG_EFI_STUB_64BIT),-march=i386 -m32)
>>> -CFLAGS_efi_stub.o := -fpic -fshort-wchar
>>> +CFLAGS_efi_stub.o := -fpic -fshort-wchar -DEFI_STUB
>>>  CFLAGS_REMOVE_efi.o := -mregparm=3 \
>>>         $(if $(CONFIG_EFI_STUB_64BIT),-march=i386 -m32)
>>> -CFLAGS_efi.o := -fpic -fshort-wchar
>>> +CFLAGS_efi.o := -fpic -fshort-wchar -DEFI_STUB
>>>
>>>  extra-$(CONFIG_EFI_STUB) += efi_stub.o efi.o
>>> --

Regards,
Bin