Re: [PATCH 00/10] Fix PEI Core issue during TemporaryRamMigration

["Ni, Ray" <ray.ni@Intel.com>]

On 2/19/2019 9:25 PM, Gao, Liming wrote:
> Ray:
> 	In PI spec, TEMPORARY_RAM_SUPPORT_PPI is described as an optional PPI that is only required for platforms that may have side effects when both Temporary RAM and Permanent RAM are enabled. If a platform does not have any side effects when both Temporary RAM and Permanent RAM are enabled, and the platform is required to disable the use of Temporary RAM, then EFI_PEI_TEMPORARY_RAM_DONE should be produced. If a platform does not have any side effects when both Temporary RAM and Permanent RAM are enabled, and the platform is not required to disable the use of Temporary RAM, then neither EFI_PEI_TEMPORARY_RAM_DONE nor EFI_PEI_TEMPORARY_RAM_SUPPORT_PPI should be produced.
> 
>      Now, real platform has no side effect. So, only TempRamDone PPI is produced. For emulator platform, is there any side effect when both Temporary RAM and Permanent RAM are enabled?
> 

No side effect when both of T-RAM and P-RAM are enabled.
Which means no side effect when neither of the PPIs is produced.
But for demo purpose, I think producing TemporaryRamDone PPI makes sense.

I will work out patches for EmulatorPkg to produce TemoraryRamDone.


> Thanks
> Liming
>> -----Original Message-----
>> From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On Behalf Of Ni, Ray
>> Sent: Tuesday, February 19, 2019 10:46 AM
>> To: Justen, Jordan L <jordan.l.justen@intel.com>; edk2-devel@lists.01.org
>> Cc: Wu, Hao A <hao.a.wu@intel.com>; Anthony Perard <anthony.perard@citrix.com>; Laszlo Ersek <lersek@redhat.com>; Zeng, Star
>> <star.zeng@intel.com>
>> Subject: Re: [edk2] [PATCH 00/10] Fix PEI Core issue during TemporaryRamMigration
>>
>> Jordan,
>> I find many real platforms do not implement the temporary ram migration
>> PPI and rely on the PeiCore migration  logic.
>> So perhaps TemporaryRamMigration PPI was added to help platform to
>> destroy the temporary RAM (CAR in x86 platform).
>> But with the introduction of TemporaryRamDone PPI, maybe the
>> TemporaryRamMigration PPI can be retired.
>> The logic in PeiCore to call TemporaryRamMigration is just for backward
>> compatibility.
>> If that's true, do you still need to enhance PeiCore?
>>
>> For the Emulator case, I already found without TemporaryRamMigration
>> the platform can still boot.
>>
>> Does OVMF hard-depend on TemporaryRamMigration? Or it can reply on
>> the PeiCore migration logic + TemporaryDone PPI?
>>
>> Thanks,
>> Ray
>>
>>> -----Original Message-----
>>> From: Justen, Jordan L <jordan.l.justen@intel.com>
>>> Sent: Monday, February 18, 2019 12:12 PM
>>> To: edk2-devel@lists.01.org
>>> Cc: Justen, Jordan L <jordan.l.justen@intel.com>; Liu Yu
>>> <pedroa.liu@outlook.com>; Andrew Fish <afish@apple.com>; Anthony
>>> Perard <anthony.perard@citrix.com>; Ard Biesheuvel
>>> <ard.biesheuvel@linaro.org>; Wu, Hao A <hao.a.wu@intel.com>; Wang, Jian
>>> J <jian.j.wang@intel.com>; Julien Grall <julien.grall@linaro.org>; Laszlo Ersek
>>> <lersek@redhat.com>; Ni, Ray <ray.ni@intel.com>; Zeng, Star
>>> <star.zeng@intel.com>
>>> Subject: [PATCH 00/10] Fix PEI Core issue during TemporaryRamMigration
>>>
>>> https://github.com/jljusten/edk2.git temp-ram-support
>>>
>>> This series fixes an issue that, while rare, is possible based on the way the
>>> TemporaryRamSupport PPI is defined along with how it is used by the PEI
>>> Core.
>>>
>>> Liu Yu reported a boot issue with EmulatorPkg, which I believe was caused by
>>> this issue.
>>>
>>> The details of the issue are described in the commit message of the
>>> "MdeModePkg/Core/Pei: Add code path to allow assembly temp-ram
>>> migration" patch.
>>>
>>> Along with this, I added a few Temporary RAM patches for EmulatorPkg and
>>> OvmfPkg.
>>>
>>> Cc: Liu Yu <pedroa.liu@outlook.com>
>>> Cc: Andrew Fish <afish@apple.com>
>>> Cc: Anthony Perard <anthony.perard@citrix.com>
>>> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>>> Cc: Hao Wu <hao.a.wu@intel.com>
>>> Cc: Jian J Wang <jian.j.wang@intel.com>
>>> Cc: Julien Grall <julien.grall@linaro.org>
>>> Cc: Laszlo Ersek <lersek@redhat.com>
>>> Cc: Ray Ni <ray.ni@intel.com>
>>> Cc: Star Zeng <star.zeng@intel.com>
>>>
>>> Jordan Justen (10):
>>>    EmulatorPkg/build.sh: Fix missing usage of -b BUILDTARGET parameter
>>>    EmulatorPkg/Unix/Host: Use PcdInitValueInTempStack to init temp-ram
>>>    EmulatorPkg/Sec: Replace assembly temp-ram support with C code
>>>    EmulatorPkg/Sec: Disable optimizations for TemporaryRamMigration
>>>      function
>>>    OvmfPkg/Sec: Swap TemporaryRam Stack and Heap locations
>>>    OvmfPkg/Sec: Disable optimizations for TemporaryRamMigration
>>>    MdeModePkg/Core/Pei: Add code path to allow assembly temp-ram
>>>      migration
>>>    MdeModulePkg/Core/Pei: Use assembly for X64 TemporaryRamMigration
>>>    MdeModulePkg/Core/Pei: Use assembly for IA32 TemporaryRamMigration
>>>    OvmfPkg/Sec: Fill Temp Ram after TemporaryRamMigration
>>>
>>>   EmulatorPkg/Sec/Ia32/SwitchRam.S              | 95 -------------------
>>>   EmulatorPkg/Sec/Ia32/SwitchRam.asm            | 94 ------------------
>>>   EmulatorPkg/Sec/Ia32/TempRam.c                | 65 -------------
>>>   EmulatorPkg/Sec/Sec.c                         | 76 ++++++++++++++-
>>>   EmulatorPkg/Sec/Sec.inf                       | 13 +--
>>>   EmulatorPkg/Sec/X64/SwitchRam.S               | 72 --------------
>>>   EmulatorPkg/Sec/X64/SwitchRam.asm             | 76 ---------------
>>>   EmulatorPkg/Unix/Host/Host.c                  |  2 +-
>>>   EmulatorPkg/Unix/Host/Host.inf                |  1 +
>>>   EmulatorPkg/build.sh                          | 10 +-
>>>   MdeModulePkg/Core/Pei/Dispatcher/Dispatcher.c | 59 ++++++++----
>>>   .../Dispatcher/Ia32/TemporaryRamMigration.S   | 72 ++++++++++++++
>>>   .../Ia32/TemporaryRamMigration.nasm           | 78 +++++++++++++++
>>>   .../Pei/Dispatcher/TemporaryRamMigration.c    | 52 ++++++++++
>>>   .../Dispatcher/X64/TemporaryRamMigration.S    | 69 ++++++++++++++
>>>   .../Dispatcher/X64/TemporaryRamMigration.nasm | 75 +++++++++++++++
>>>   MdeModulePkg/Core/Pei/PeiMain.h               | 52 ++++++++++
>>>   MdeModulePkg/Core/Pei/PeiMain.inf             | 14 +++
>>>   OvmfPkg/Sec/Ia32/SecEntry.nasm                |  2 +-
>>>   OvmfPkg/Sec/SecMain.c                         | 59 ++++++++----
>>>   OvmfPkg/Sec/X64/SecEntry.nasm                 |  2 +-
>>>   21 files changed, 577 insertions(+), 461 deletions(-)  delete mode 100644
>>> EmulatorPkg/Sec/Ia32/SwitchRam.S  delete mode 100644
>>> EmulatorPkg/Sec/Ia32/SwitchRam.asm
>>>   delete mode 100644 EmulatorPkg/Sec/Ia32/TempRam.c  delete mode
>>> 100644 EmulatorPkg/Sec/X64/SwitchRam.S  delete mode 100644
>>> EmulatorPkg/Sec/X64/SwitchRam.asm  create mode 100644
>>> MdeModulePkg/Core/Pei/Dispatcher/Ia32/TemporaryRamMigration.S
>>>   create mode 100644
>>> MdeModulePkg/Core/Pei/Dispatcher/Ia32/TemporaryRamMigration.nasm
>>>   create mode 100644
>>> MdeModulePkg/Core/Pei/Dispatcher/TemporaryRamMigration.c
>>>   create mode 100644
>>> MdeModulePkg/Core/Pei/Dispatcher/X64/TemporaryRamMigration.S
>>>   create mode 100644
>>> MdeModulePkg/Core/Pei/Dispatcher/X64/TemporaryRamMigration.nasm
>>>
>>> --
>>> 2.20.0.rc1
>>
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-- 
Thanks,
Ray