From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from m16.mail.163.com (m16.mail.163.com [117.135.210.3]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 575161DF26B; Tue, 15 Jul 2025 14:55:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=117.135.210.3 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752591335; cv=none; b=KsGY/onODa4v7rNmK5Q/IcF3gEwvOV0ztEiN1/fcpvbijM5PRHhpi79O0sVXeAgHK8SZbvcbhLpcySPRA+2igByxtv22diEYtMtpLrP++Voccgo7Wnx+0t03+Lbsw2/hB9MdzE/kRds7+LvurfVs3hGsO3F5zyOPN3x3EHTn61A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752591335; c=relaxed/simple; bh=txUfSwjyOVKeDzlPKIBEVTgZb3j/w8eAWl4cWJAms9Y=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=UI4p0iJixg0K5HIc9P/EeBuu5GdBGWmm6PAcvh66hx6zBBvjXTPxKXOq7BHwyM302YYX8inJi51+MHAOZ50RqEipwmoQ+NtU32q+RITWqYuABOcZ8CGESdsOC4n0mJ/5xtHI44HPZZVY5yCwM654A+dgdgTqxIufmWAWvJOn35g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com; spf=pass smtp.mailfrom=163.com; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b=nehBQBhg; arc=none smtp.client-ip=117.135.210.3 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=163.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="nehBQBhg" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=Message-ID:Date:MIME-Version:Subject:To:From: Content-Type; bh=SP7dE1bKFm+Zk1R9d8gy12/jTWzAHbDIeWSSV5I0Ffw=; b=nehBQBhggmGzsVClzFYyo3YKVar9NmcrCXQKH8/hXqk5TfLczz5c1ul8b+/3Md Gi6wgadAcqQOQ3nTTgkOj1J6DmC5lmBoBBWwQ4MzVcGoj70yWjogVitdw/yXdeiT W/lcliVaXiL2IhxP/n8ycjonrgMtKRzJdTYd4i0BLSrKk= Received: from [IPV6:240e:b8f:919b:3100:7981:39b4:a847:709a] (unknown []) by gzga-smtp-mtada-g1-2 (Coremail) with SMTP id _____wCHnzWFa3ZoCeijFA--.44532S2; Tue, 15 Jul 2025 22:53:58 +0800 (CST) Message-ID: <64e0809b-b931-4820-8f61-377db0dbfc49@163.com> Date: Tue, 15 Jul 2025 22:53:56 +0800 Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 06/11] PCI/ASPM: Clear aspm_disable as part of __pci_enable_link_state() To: Manivannan Sadhasivam Cc: Bjorn Helgaas , =?UTF-8?Q?Ilpo_J=C3=A4rvinen?= , Krishna Chaitanya Chundru , Bjorn Helgaas , Jingoo Han , Lorenzo Pieralisi , Rob Herring , Jeff Johnson , Bartosz Golaszewski , =?UTF-8?Q?Krzysztof_Wilczy=C5=84ski?= , linux-pci@vger.kernel.org, LKML , linux-arm-msm@vger.kernel.org, mhi@lists.linux.dev, linux-wireless@vger.kernel.org, ath11k@lists.infradead.org, qiang.yu@oss.qualcomm.com, quic_vbadigan@quicinc.com, quic_vpernami@quicinc.com, quic_mrana@quicinc.com, Jeff Johnson References: <604ffae3-1bfc-0922-b001-f3338880eb21@linux.intel.com> <20250711230013.GA2309106@bhelgaas> <470742a6-861e-498e-9da4-1fa213969c7e@163.com> Content-Language: en-US From: Hans Zhang <18255117159@163.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CM-TRANSID:_____wCHnzWFa3ZoCeijFA--.44532S2 X-Coremail-Antispam: 1Uf129KBjvJXoWxArWrZw1kuF45Gr4rZFykGrg_yoW5Gr43pF WFyFySka1kArn7Cw12qw1UJFyYyw4Syry5W34Fqw1UAFs093s7Jr47trWruF9xWr4xZw1j vrWYgF9rXFyq9aDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07UizVbUUUUU= X-CM-SenderInfo: rpryjkyvrrlimvzbiqqrwthudrp/1tbiQwOLo2h2Y3mlqwAAsi On 2025/7/13 01:02, Manivannan Sadhasivam wrote: > On Sun, Jul 13, 2025 at 12:05:18AM GMT, Hans Zhang wrote: >> >> >> On 2025/7/12 17:35, Manivannan Sadhasivam wrote: >>>> We only have two callers of this (pcie-qcom.c and vmd.c, both in >>>> drivers/pci/), so it's not clear to me that it needs to be in >>>> include/linux/pci.h. >>>> >>>> I'm a little dubious about it in the first place since I don't think >>>> drivers should be enabling ASPM states on their own, but pcie-qcom.c >>>> and vmd.c are PCIe controller drivers, not PCI device drivers, so I >>>> guess we can live with them for now. >>>> >>>> IMO the "someday" goal should be that we get rid of aspm_policy and >>>> enable all the available power saving states by default. We have >>>> sysfs knobs that administrators can use if necessary, and drivers or >>>> quirks can disable states if they need to work around hardware >>>> defects. >>>> >>> >>> Yeah, I think the default should be powersave and let the users disable it for >>> performance if they want. >>> >> >> Dear Bjorn and Mani, >> >> Perhaps I don't think so. At present, our company's testing team has tested >> quite a few NVMe SSDS. As far as I can remember, the SSDS from two companies >> have encountered problems and will hang directly when turned on. We have set >> CONFIG_PCIEASPM_POWERSAVE=y by default. When encountering SSDS from these >> two companies, we had to add "pcie_aspm.policy=default" in the cmdline, and >> then the boot worked normally. Currently, we do not have a PCIe protocol >> analyzer to analyze such issues. The current approach is to modify the >> cmdline. So I can't prove whether it's a problem with the Root Port of our >> SOC or the SSD device. >> >> Here I agree with Bjorn's statement that sometimes the EP is not necessarily >> very standard and there are no hardware issues. Personally, I think the >> default is default or performance. When users need to save power, they >> should then decide whether to configure it as powersave or powersupersave. >> Sometimes, if the EP device connected by the customer is perfect, they can >> turn it on to save power. But if the EP is not perfect, at least they will >> immediately know what caused the problem. >> > > We all agree that not all endpoints are standards compliant. So if they have any > issues with ASPM, then ASPM for those devices should be disabled in the quirks > or in the device driver. > > That said, the change that Bjorn proposed is not going to happen in the > immediate future. Dear Mani, Ok, I will keep an eye on the changes of ASPM. Best regards, Hans