Re: [edk2-devel] [PATCH 1/1] MdeModulePkg/BdsDxe: Also call PlatformBootManagerWaitCallback on 0

["Liming Gao" <liming.gao@intel.com>]

This change is good to me. I also verify it in Emulator platform. 

Reviewed-by: Liming Gao <liming.gao@intel.com>

Thanks
Liming
>-----Original Message-----
>From: devel@edk2.groups.io [mailto:devel@edk2.groups.io] On Behalf Of
>Laszlo Ersek
>Sent: Friday, September 27, 2019 3:30 AM
>To: devel@edk2.groups.io; pete@akeo.ie
>Cc: Gao, Zhichao <zhichao.gao@intel.com>; Ni, Ray <ray.ni@intel.com>
>Subject: Re: [edk2-devel] [PATCH 1/1] MdeModulePkg/BdsDxe: Also call
>PlatformBootManagerWaitCallback on 0
>
>On 09/25/19 17:50, Pete Batard wrote:
>> The existing loop is set to call PlatformBootManagerWaitCallback every
>> second except the last one. We believe this is a mistake as it prevents
>> the called code from performing timeout expiration tasks such as, for
>> instance, ensuring that the last segment of a progress bar is displayed
>> before continuing (which is a current issue for the RPi3 platform).
>>
>> Signed-off-by: Pete Batard <pete@akeo.ie>
>> ---
>>  MdeModulePkg/Universal/BdsDxe/BdsEntry.c | 1 +
>>  1 file changed, 1 insertion(+)
>>
>> diff --git a/MdeModulePkg/Universal/BdsDxe/BdsEntry.c
>b/MdeModulePkg/Universal/BdsDxe/BdsEntry.c
>> index f3d5e5ac0615..7968a58f3454 100644
>> --- a/MdeModulePkg/Universal/BdsDxe/BdsEntry.c
>> +++ b/MdeModulePkg/Universal/BdsDxe/BdsEntry.c
>> @@ -341,6 +341,7 @@ BdsWait (
>>        TimeoutRemain--;
>>      }
>>    }
>> +  PlatformBootManagerWaitCallback (0);
>>    DEBUG ((EFI_D_INFO, "[Bds]Exit the waiting!\n"));
>>  }
>>
>>
>
>I can confirm the problem statement, from a quick test with OVMF.
>
>Regarding the PlatformBootManagerWaitCallback (0) call, it promises to
>do the right thing, considering the following library instances:
>
>- ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBm.c
>- OvmfPkg/Library/PlatformBootManagerLib/BdsPlatform.c
>
>In both cases, the function goes,
>
>VOID
>EFIAPI
>PlatformBootManagerWaitCallback (
>  UINT16          TimeoutRemain
>  )
>{
>  EFI_GRAPHICS_OUTPUT_BLT_PIXEL_UNION Black;
>  EFI_GRAPHICS_OUTPUT_BLT_PIXEL_UNION White;
>  UINT16                              Timeout;
>
>  Timeout = PcdGet16 (PcdPlatformBootTimeOut);
>
>  Black.Raw = 0x00000000;
>  White.Raw = 0x00FFFFFF;
>
>  BootLogoUpdateProgress (
>    White.Pixel,
>    Black.Pixel,
>    L"Start boot option",
>    White.Pixel,
>    (Timeout - TimeoutRemain) * 100 / Timeout,
>    0
>    );
>}
>
>If we substitute 0 for TimeoutRemain in the BootLogoUpdateProgress()
>call, we get (Timeout * 100 / Timeout), i.e. 100%.
>
>I haven't tested the patch, and I can't review it quickly for real, but
>it looks plausible to me.
>
>Thanks
>Laszlo
>
>