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Date: Tue, 23 May 2023 07:44:31 +0200
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Subject: Re: managing memory attributes in PEI
To: Gerd Hoffmann <kraxel@redhat.com>, Ard Biesheuvel <ardb@kernel.org>
Cc: edk2-devel-groups-io <devel@edk2.groups.io>, Ray Ni <ray.ni@intel.com>,
 Jiewen Yao <jiewen.yao@intel.com>, Taylor Beebe <t@taylorbeebe.com>,
 Oliver Smith-Denny <osd@smith-denny.com>
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From: "Laszlo Ersek" <lersek@redhat.com>
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On 5/22/23 14:06, Gerd Hoffmann wrote:
>> So my questions are:
>> - do we need to retain mixed IA32 / X64 support, and if so, why? (I
>> think it is related to SMM emulation but I need someone to confirm
>> this)
> 
> Yes, it's SMM related.  S3 suspend in SMM-enabled builds requires
> 32bit PEI.
> 
> Intel seems to be working on removing the IA32 dependency, by adding
> full X64 support to various places in the code base.  There have been
> numerous patch sets on the list over the last months, some of them
> are merged meanwhile.  As far I know the patch series addressing the
> suspend problem is not yet merged (Ray, Jiewen, please correct me if
> I'm wrong).

You've forgotten about our discussion in <https://bugzilla.tianocore.org/show_bug.cgi?id=4195> :)

> So, right now we still need that, but I expect that to change in near
> future.

BTW just last evening I found out about X86-S:

- https://www.phoronix.com/news/Intel-X86-S-64-bit-Only
- https://www.intel.com/content/www/us/en/developer/articles/technical/envisioning-future-simplified-architecture.html
- https://cdrdv2.intel.com/v1/dl/getContent/776648

I'm slightly curious if those IA32->X64 "replacement" patches you mention are related to X86-S ;)

Laszlo