Re: [edk2-devel] [PATCH] UefiCpuPkg: Adding a new TSC library by using CPUID(0x15) TSC leaf

["Laszlo Ersek" <lersek@redhat.com>]

On 08/16/19 18:16, Laszlo Ersek wrote:
> On 08/15/19 06:02, Gao, Liming wrote:
>> Donald: This change is a new feature. Now, it is not in edk2 feature
>> planning list. If you want to catch it into 201908 stable tag, please
>> get approve from Stewards first. I have cc this mail to all Stewards.
> - I don't mind adding a new feature, as long as it gets properly
> reviewed by package owners before we enter the soft feature freeze.
> 
> - Looking at the BZ
> <https://bugzilla.tianocore.org/show_bug.cgi?id=1909>, a bit more
> documentation would be nice.
> 
> - On the negative side, I'm very much *not* a fan of adding features to
> the open source edk2 tree without actually *consuming* the feature in an
> open source tree. Are the new library instances going to be put to use
> in edk2-platforms, perhaps?
> 
> We discussed this topic earlier on some of the stewards' calls. On one
> hand, it's not uncommon to see library instances from Intel enter core
> edk2 packages without any dependent platform code, or even a detailed
> problem statement / purpose description (see e.g. commit 5c9bb86f171c
> and its surrounding commits). On the other hand, attempts in the past,
> to add libraries with well demonstrated and direct in-tree use cases, to
> edk2 core, have been rejected, from other submitters. (Here's one
> example: <https://bugzilla.tianocore.org/show_bug.cgi?id=957>.) I'm not
> prying at proprietary platform information, but a new library added to
> edk2 core *should* be well-justified.
> 
> The commit message on this patch is empty. It only references
> <https://bugzilla.tianocore.org/show_bug.cgi?id=1909>. And if I open the
> BZ, this is all I get:
> 
>     Need a new TSC library to check the CPUID leaf (EAX=0x15) for TSC.
>     For new platform (start from SKL) can use CPUID and retire/remove
>     the current override from AcpiTimerLib.
> 
> Does this read like an actual feature request? (TimerLib is an MdePkg
> library class, so not exactly "niche".)

In comparison, the following email does read like a feature request:

[edk2-devel] Determining TSC frequency programmatically
https://edk2.groups.io/g/devel/message/45750
http://mid.mail-archive.com/8EC14D0D-DFA5-412D-A4E1-4D641576D58E@protonmail.com

If the posting is related to TianoCore#1909, then I urge the BZ assignee to please reference the message in the TianoCore BZ.

Thanks
Laszlo