[U-Boot] [PATCH 1/1] efi_loader: allow return value in EFI_CALL

[Heinrich Schuchardt]

On 08/17/2017 01:49 PM, Rob Clark wrote:
> On Tue, Aug 15, 2017 at 3:42 PM, Heinrich Schuchardt <xypron.glpk at gmx.de> wrote:
>> Macro EFI_CALL was introduced to call an UEFI function.
>> Unfortunately is did not support return values.
>> Most UEFI functions have a return value.
>>
>> So let's rename EFI_CALL to EFI_CALL_VOID and introduce a
>> new EFI_CALL macro that supports return values.
>>
>> Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
>> ---
>>  include/efi_loader.h          | 16 ++++++++++++++--
>>  lib/efi_loader/efi_boottime.c |  3 ++-
>>  2 files changed, 16 insertions(+), 3 deletions(-)
>>
>> diff --git a/include/efi_loader.h b/include/efi_loader.h
>> index 037cc7c543..1cee10ea0c 100644
>> --- a/include/efi_loader.h
>> +++ b/include/efi_loader.h
>> @@ -41,9 +41,21 @@ const char *__efi_nesting_dec(void);
>>         })
>>
>>  /*
>> - * Callback into UEFI world from u-boot:
>> + * Call non-void UEFI function from u-boot and retrieve return value:
>>   */
>> -#define EFI_CALL(exp) do { \
>> +#define EFI_CALL(exp) ({ \
>> +       debug("%sEFI: Call: %s\n", __efi_nesting_inc(), #exp); \
>> +       assert(__efi_exit_check()); \
>> +       typeof(exp) r = exp; \
>> +       assert(__efi_entry_check()); \
>> +       debug("%sEFI: Return From: %s\n", __efi_nesting_dec(), #exp); \
>> +       r; \
>> +})
>> +
> 
> So, I had considered something similar, for the purposes of being able
> to print return value, but in the end decided that the EFI_EXIT()
> print was usually sufficient (except in cases where you enable DEBUG
> in some files but not others), and opted for the simpler MACRO(ret =
> somecall()) approach.. also the longer macro name makes not going over
> 80 chars harder in some cases ;-)
> 
> I don't really feel strongly one way or another.. but I guess if we do
> this we might as well add the return value (cast to u64 and print as
> hex to cover both ptrs and efi_status_t?) to the "Return From" debug
> print.

We already print the return value in EFI_EXIT.
Why should we print it twice?

In c160d2f5ec9

Regards

Heinrich

> 
> BR,
> -R
> 
>> +/*
>> + * Call void UEFI function world from u-boot:
>> + */
>> +#define EFI_CALL_VOID(exp) do { \
>>         debug("%sEFI: Call: %s\n", __efi_nesting_inc(), #exp); \
>>         assert(__efi_exit_check()); \
>>         exp; \
>> diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
>> index 43f32385fa..6489a32505 100644
>> --- a/lib/efi_loader/efi_boottime.c
>> +++ b/lib/efi_loader/efi_boottime.c
>> @@ -158,7 +158,8 @@ void efi_signal_event(struct efi_event *event)
>>                 return;
>>         event->signaled = 1;
>>         if (event->type & EVT_NOTIFY_SIGNAL) {
>> -               EFI_CALL(event->notify_function(event, event->notify_context));
>> +               EFI_CALL_VOID(event->notify_function(event,
>> +                                                    event->notify_context));
>>         }
>>  }
>>
>> --
>> 2.14.1
>>
>