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

[Simon Glass]

Hi Bin,

On 26 September 2016 at 20:44, Bin Meng <bmeng.cn at gmail.com> wrote:
> 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.

Yes that's right. But in the case of the stub, it can be different
from U-Boot itself. This case takes care of that.

>
>>>
>>>>  #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,
Simon