Liming,

That is awesome, thank you! My recommendation is moving all of our MinPlatform builds to this new toolchain then!

Thanks,

Nate

From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of gaoliming
Sent: Monday, October 12, 2020 7:29 PM
To: devel@edk2.groups.io; afish@apple.com; michael.kubacki@outlook.com
Cc: Desimone, Nathaniel L <nathaniel.l.desimone@intel.com>; 'Leif Lindholm' <leif@nuviainc.com>; 'Laszlo Ersek' <lersek@redhat.com>; 'Ard Biesheuvel' <ard.biesheuvel@arm.com>; Ni, Ray <ray.ni@intel.com>; Chaganty, Rangasai V <rangasai.v.chaganty@intel.com>; Dong, Eric <eric.dong@intel.com>; Bi, Dandan <dandan.bi@intel.com>; Kinney, Michael D <michael.d.kinney@intel.com>; Steele, Kelly <kelly.steele@intel.com>; Sun, Zailiang <zailiang.sun@intel.com>; Qian, Yi <yi.qian@intel.com>; Chiu, Chasel <chasel.chiu@intel.com>; Agyeman, Prince <prince.agyeman@intel.com>; Feng, Bob C <bob.c.feng@intel.com>; 'Abner Chang' <abner.chang@hpe.com>; 'Daniel Schaefer' <daniel.schaefer@hpe.com>; 'Gilbert Chen' <gilbert.chen@hpe.com>; 'Christian Walter' <christian.walter@9elements.com>
Subject: 回复: [edk2-devel] [edk2-platforms] [RFC] Compatibility Expectations in edk2-platforms

CLANG tool issue has been resolved. CLANGPDB tool chain has been added in Edk2. OVMF IA32X64 platform has been verified on Windows/Linux/Mac with CLANGPDB tool chain. On release build, OVMF IA32X64 can generates the same binary BIOS images on Windows/Linux/Mac OS. 

Here is wiki page https://github.com/tianocore/tianocore.github.io/wiki/CLANG9-Tools-Chain.

Thanks

Liming

发件人: bounce+27952+65963+4905953+8761045@groups.io <bounce+27952+65963+4905953+8761045@groups.io> 代表 Andrew Fish via groups.io
发送时间: 2020年10月7日 13:42
收件人: edk2-devel-groups-io <devel@edk2.groups.io>; michael.kubacki@outlook.com
抄送: Desimone, Nathaniel L <nathaniel.l.desimone@intel.com>; Leif Lindholm <leif@nuviainc.com>; Laszlo Ersek <lersek@redhat.com>; Ard Biesheuvel <ard.biesheuvel@arm.com>; Ni, Ray <ray.ni@intel.com>; Chaganty, Rangasai V <rangasai.v.chaganty@intel.com>; Dong, Eric <eric.dong@intel.com>; Bi, Dandan <dandan.bi@intel.com>; Mike Kinney <michael.d.kinney@intel.com>; Steele, Kelly <kelly.steele@intel.com>; Sun, Zailiang <zailiang.sun@intel.com>; Qian, Yi <yi.qian@intel.com>; Chiu, Chasel <chasel.chiu@intel.com>; Agyeman, Prince <prince.agyeman@intel.com>; Feng, Bob C <bob.c.feng@intel.com>; Liming Gao <gaoliming@byosoft.com.cn>; Abner Chang <abner.chang@hpe.com>; Daniel Schaefer <daniel.schaefer@hpe.com>; Gilbert Chen <gilbert.chen@hpe.com>; Christian Walter <christian.walter@9elements.com>
主题: Re: [edk2-devel] [edk2-platforms] [RFC] Compatibility Expectations in edk2-platforms

On Oct 6, 2020, at 10:01 PM, Michael Kubacki <michael.kubacki@outlook.com> wrote:

Hi Nate,

On 10/6/2020 9:19 PM, Desimone, Nathaniel L wrote:

Hey Michael,
On 10/5/20, 3:36 PM, Michael Kubacki <michael.kubacki@outlook.com> wrote:

1. Inconsistent maintainer support
    * Some packages currently do not build. Some packages are not getting
updated often.

    * Example: Last week I had to update Vlv2TbltDevicePkg which did not
build.
    * Example: Many packages only document support for old toolchains.

100% agreed here.

2. Inconsistent toolchain support

To build these according to instruction, a developer needs to install Visual
Studio dating back to 2015 (though it is 2020), and multiple versions of iASL,
NASM, a separate host OS for Linux/Windows builds, etc.

IMHO, the best way forward would be to finish the EDK II native clang port that Liming started some time ago. This would need to include robust support for Windows, Linux, and Mac host systems. From what I remember the last status update was issues with stability of the LLVM linker's support for PE/COFF output.

Aligning on Clang support would be great. It's worth noting that current CI support in edk2 does not support Clang so that needs to be enabled - https://github.com/tianocore/edk2/blob/master/.pytool/Readme.md.

Is adding a new toolchain just a documenting the config, and testing? 

Thanks,

Andrew Fish

Is anyone looking at those LLVM issues now?

Otherwise build reproducibility will always be a problem since the binary generated will be different depending on which OS/compiler the developer was using at the time. The coreboot community handles this issue by only supporting GCC, which I think is inappropriate for TianoCore since Windows ports of GCC differ greatly from Linux versions. While I think the goal of supporting many different C toolchains is admirable and definitely appropriate for edk2 core code... for edk2-platforms I think it would be better to have everyone agree on a single cross-platform toolchain; at least for x86 and ARM since clang supports those architectures well (maybe other architectures depending on the clang's maturity.)

3. Inconsistent build requirements

Many builds use the "build" command. Others have script wrappers with
unique parameters. Platforms are free to choose what they do and do not
support and developers have to figure it out.

We solved that for MinPlatform based boards with build_bios.py, but agreed that that at an overall project level this is still an issue. I believe Bob and Liming were working on adding extensibility to BaseTools needed for "build" to work everywhere, but I'm not sure what the status of that work is.

I've always liked the simplicity of build_bios.py. There's also a lot of effort put into edk2-pytool-extensions. I'm not partial to any particular solution as I've had positive experiences with both but having more consistency at a repo level would be awesome.

Perhaps a community discussion around leveraging existing tool support for open source platforms would help with adoption. Apart from consistency across open source platforms, usage could also serve as a practical example to closed source consumers on how to better integrate such tools into their environments.

4. Lack of build health indicators

Basically, there is no public CI across platforms. It is not clear exactly what
platform builds are broken, what configurations they are broken against,
how long they have been broken, etc.

Public CI seems like a great idea. Public automated testing would also be awesome. I believe 9elements has been working on building a pool of hardware for automated testing of Open System Firmware, maybe we should check and see if they would be interested in supporting automated testing for TianoCore. We would also need to see what the intersection is between what they have in their pool and what boards are supported in edk2-platforms.

I look forward to hearing from 9elements.

Do you think it would be feasible for Intel to support something like KabylakeOpenBoardPkg/GalagoPro3 and/or WhiskeylakeOpenBoardPkg/UpXtreme in public CI?

Without such support, I believe platforms can only have a dependency on
edk2 (not vice versa). Maintainers move their edk2 pointer when they have
verified that their platform properly integrates the latest changes. This is
relatively common in relationships with package-based dependencies and
how this is typically handled outside edk2-platforms. I believe this is
reasonable even with public CI in place unless maintainers understand and
accept the challenges and additional support that is involved with being on
edk2/master.

Coreboot handles this problem by auditing the how good the maintenance is of boards over time. If a given board becomes stale, then the board becomes a candidate for getting deleted from master and moved to a legacy branch. Sometimes entire technologies are dropped, for example FSP v1.0 is only supported up to coreboot 4.11, for that reason there is a long-lived 4.11_branch in coreboot git to maintain platforms dependent on FSP v1.0 binaries.
I think we need some sort of deprecation process for edk2-platforms as well because as you note, the Bay Trail Minnow Max is not receiving particularly good maintenance at this point. A similar issue happened with PurleyOpenBoardPkg last year and you actually sent the patch series to delete it.

Deprecation branches sound reasonable to me personally. I'm not aware of prior documentation or discussion around platform deprecation in edk2-platforms. Is anyone else?

I just wanted to give my observation of some recent challenges and see if
the community can align on some practices to help simplify edk2-platforms
integration and testing.

Thanks,
Michael