From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4C38A8C0B; Wed, 19 Feb 2025 03:56:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739937405; cv=none; b=Bx/QcU7bbMAHuDExlnoZQoV5KThAJ1QthdRHx9Ns10lvFFBucguIT3ZctogCnRy/adXnT7u7zJqIjA6UR3CvTfl+YfCzmEgfUislbQVFAi7xCTOi66hn6EH5ZXTwqk770bgPPvhpwWRcbJgyaOW6Dv5dOVOgRM0VA3nmjeAyAzI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739937405; c=relaxed/simple; bh=i5IcOWQi0O8bxInU7mflve6qdpwNp+GrKXSYxYEM57s=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=sbRuZhdEtDnU3GpmcCFtZ/x0In1wG9HjrRr20yovqw21wxrddw1YuwNQrBjfeh76mLKpIlyj0qQB4qGH806s0aLf/FGPF7o0JesqzEFTLg6tQU9UA/cffUzUqUgFLL5JLK6Kv3V4Dfl445PoVlcbfm3yTtxY3wHHpFrOKfKuN8o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=s/tE3AWb; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="s/tE3AWb" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EA144C4CED1; Wed, 19 Feb 2025 03:56:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1739937404; bh=i5IcOWQi0O8bxInU7mflve6qdpwNp+GrKXSYxYEM57s=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=s/tE3AWbM5GT5p2/ZuZ4WwfbyXzJSizCAvKFCbsipvVELsg1r9AvXkg/D6KpdLMeT 846n4D5dBMkjtmZMQ7WY8bMF4mR3gbYz0DMgq4JKdecEjbc3DNuhA/ewAlOGMsdRpk PWh27OuBkU9mePxAVgJt3UFtF6sKq2x558kpYWGioYane6f+bXb99Zj7+NCP6sZLJG 5C68y9dIV9OH37lpVvCrtCmg6icG4PB5eApB+9ABZMbmFmTWWh1Sx55jd712vQmIxP bzBG2cq72fWsSctK3AJMfkJFNvcX2lNLpI10w/1KuUKoIzw+gnIJGFI54V+JRRkYD4 d6aBQhyjPx9UA== Message-ID: Date: Tue, 18 Feb 2025 21:56:42 -0600 Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] PCI/PM: Put devices to low power state on shutdown To: Bjorn Helgaas Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, AceLan Kao , "Limonciello, Mario" , Mark Pearson , Kai-Heng Feng , mika.westerberg@linux.intel.com References: <20241208074147.22945-1-kaihengf@nvidia.com> <69ddda46-62cc-445f-a1ef-f4651ec0b138@app.fastmail.com> Content-Language: en-US From: Mario Limonciello In-Reply-To: <69ddda46-62cc-445f-a1ef-f4651ec0b138@app.fastmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 1/17/25 14:31, Mark Pearson wrote: > Hi, > > On Sun, Dec 8, 2024, at 2:41 AM, Kai-Heng Feng wrote: >> Some laptops wake up after poweroff when HP Thunderbolt Dock G4 is >> connected. >> >> The following error message can be found during shutdown: >> pcieport 0000:00:1d.0: AER: Correctable error message received from >> 0000:09:04.0 >> pcieport 0000:09:04.0: PCIe Bus Error: severity=Correctable, type=Data >> Link Layer, (Receiver ID) >> pcieport 0000:09:04.0: device [8086:0b26] error >> status/mask=00000080/00002000 >> pcieport 0000:09:04.0: [ 7] BadDLLP >> >> Calling aer_remove() during shutdown can quiesce the error message, >> however the spurious wakeup still happens. >> >> The issue won't happen if the device is in D3 before system shutdown, so >> putting device to low power state before shutdown to solve the issue. >> >> ACPI Spec 6.5, "7.4.2.5 System \_S4 State" says "Devices states are >> compatible with the current Power Resource states. In other words, all >> devices are in the D3 state when the system state is S4." >> >> The following "7.4.2.6 System \_S5 State (Soft Off)" states "The S5 >> state is similar to the S4 state except that OSPM does not save any >> context." so it's safe to assume devices should be at D3 for S5. >> >> Link: https://bugzilla.kernel.org/show_bug.cgi?id=219036 >> Cc: AceLan Kao >> Reviewed-by: Mario Limonciello >> Tested-by: Mario Limonciello >> Signed-off-by: Kai-Heng Feng >> --- >> drivers/pci/pci-driver.c | 8 ++++++++ >> 1 file changed, 8 insertions(+) >> >> diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c >> index 35270172c833..248e0c9fd161 100644 >> --- a/drivers/pci/pci-driver.c >> +++ b/drivers/pci/pci-driver.c >> @@ -510,6 +510,14 @@ static void pci_device_shutdown(struct device *dev) >> if (drv && drv->shutdown) >> drv->shutdown(pci_dev); >> >> + /* >> + * If driver already changed device's power state, it can mean the >> + * wakeup setting is in place, or a workaround is used. Hence keep it >> + * as is. >> + */ >> + if (!kexec_in_progress && pci_dev->current_state == PCI_D0) >> + pci_prepare_to_sleep(pci_dev); >> + >> /* >> * If this is a kexec reboot, turn off Bus Master bit on the >> * device to tell it to not continue to do DMA. Don't touch >> -- >> 2.47.0 > > Just a note that we've tested this in the Lenovo Linux team and confirmed that it reduces the power draw on a powered off Z16 G2 by 0.6W. > This is enough to bring Linux inline with Windows, and more importantly allow the platform to pass e-star energy certification (which it otherwise fails). We suspect other platforms will show similar benefits. > > Let me know if there's anything we can do to help get this patch moving along - I think it's important. > > Tested-by: Mark Pearson > > Mark > Bjorn, Anything else that you would like to see for this patch? Or different direction you would like to see it go? Thanks,