linux-kernel - Re: [PATCH] ACPI: EC: Fix CPU frequency limitation on AMD platforms after suspend/resume

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Message-ID: <369d0a74-4d5d-40e9-aa87-86c7563cf019@amd.com>
Date: Mon, 28 Apr 2025 14:10:58 -0500
From: Mario Limonciello <mario.limonciello@....com>
To: "Rafael J. Wysocki" <rafael@...nel.org>
Cc: Marcus Bergo <marcusbergo@...il.com>, mark.pearson@...ovo.com,
 linux-acpi@...r.kernel.org, platform-driver-x86@...r.kernel.org,
 lenb@...nel.org, LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] ACPI: EC: Fix CPU frequency limitation on AMD platforms
 after suspend/resume

On 4/28/2025 2:02 PM, Rafael J. Wysocki wrote:
> On Mon, Apr 28, 2025 at 8:23 PM Mario Limonciello
> <mario.limonciello@....com> wrote:
>>
>> On 4/28/2025 4:51 AM, Marcus Bergo wrote:
>>> Yes, it does.
>>>
>>
>> OK thanks for confirming.  Considering your finding with this patch
>> you've shared and knowing there is a timing dependency that delaying the
>> next s2idle cycle helps I do wonder if we should keep exploring.
>>
>> Rafael, do you have thoughts here?  Specifically do you think it's worth
>> revisiting if b5539eb5ee70 was the correct move.
> 
> Well, it was done for a reason that is explained in its changelog.  I
> think that the problem addressed by it is genuine, isn't it?
> 
I mean yes - of course.  My inquiry was whether this should be the 
default behavior or if it should have been a quirked behavior.

I don't have a good sense for the rest of the ecosystem what the impacts 
would really be at flipping it.  Would it be worth adding a module 
parameter debug knob and survey what happens on a wide variety of machines?