From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-132.freemail.mail.aliyun.com (out30-132.freemail.mail.aliyun.com [115.124.30.132]) (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 787202EC083; Wed, 5 Nov 2025 10:22:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.132 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762338164; cv=none; b=R7SN0JfvtXGn9csz3yPElCd9ILMuax8p/myndfZ8JlmTFM7uc3kS5n/CGbkdfbINZ7SjkTewAcsrX7QnMQj7ZluFvpU6TQY9l7Kn8CCbteisvGUoX7kYSJn+0Kz1ZF3BOZFFs5mCwa0VE1/lHJ4O1A/VJf3cBhPRhhljzaYeP28= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762338164; c=relaxed/simple; bh=ItYXVK2PdUIcKip20t5lPFH0eehgUIl+xtt3Ngpl7Qc=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=TvchVeAXIVXD2xLM5FkfHU9fTaSmMwgskSzGCBnE1RNFgVhw3hDsfcbRGJ5qfV0r5Khhg55hc/ysaFPee5EKYOKBfhfY5oQSU3LBNMN9gMxUk7zFtVjJEQBc/IOkN4A8laP/P303QQKt1Tq0W2DfQKs9QW856zGOZqoSbqsx/0E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=l5Yf4g9g; arc=none smtp.client-ip=115.124.30.132 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="l5Yf4g9g" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1762338153; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=wUXBxSgyHViOpb4J0afxMYP8uNQ8fKWBiLqr1WSZuQs=; b=l5Yf4g9gzAfiD2cmagb0T8aL1q+wDwfxJ3GcDSWp6R2jvtWUwuHWIQZo7Z3H981DfKLT1RqSrCtKYNh4dzbNDXW5hfSWn8UFiLpjToJBNU6LViZt5EESWmO/zeT0j1q6H72A6wD31446R+/EtBAStMK/xC3CRhVoWO95JnGebAk= Received: from 30.50.177.113(mailfrom:guwen@linux.alibaba.com fp:SMTPD_---0Wrl49Gy_1762338144 cluster:ay36) by smtp.aliyun-inc.com; Wed, 05 Nov 2025 18:22:31 +0800 Message-ID: <8a74f801-1de5-4a1d-adc7-66a91221485d@linux.alibaba.com> Date: Wed, 5 Nov 2025 18:22:19 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net-next v5 1/2] ptp: introduce Alibaba CIPU PHC driver To: Jakub Kicinski Cc: richardcochran@gmail.com, andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com, pabeni@redhat.com, xuanzhuo@linux.alibaba.com, dust.li@linux.alibaba.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <20251030121314.56729-1-guwen@linux.alibaba.com> <20251030121314.56729-2-guwen@linux.alibaba.com> <20251031165820.70353b68@kernel.org> From: Wen Gu In-Reply-To: <20251031165820.70353b68@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2025/11/1 07:58, Jakub Kicinski wrote: > On Thu, 30 Oct 2025 20:13:13 +0800 Wen Gu wrote: >> This adds a driver for Alibaba CIPU PTP clock. The CIPU, an underlying >> infrastructure of Alibaba Cloud, synchronizes time with atomic clocks >> via the network and provides microsecond or sub-microsecond precision >> timestamps for VMs and bare metals on cloud. >> >> User space processes, such as chrony, running in VMs or on bare metals >> can get the high precision time through the PTP device exposed by this >> driver. > > As mentioned on previous revisions this is a pure clock device which has > nothing to do with networking and PTP. I don't quite agree that this has nothing to do with PTP. What is the difference between this CIPU PTP driver and other PTP drivers under drivers/ptp? such as ptp_s390, ptp_vmw, ptp_pch, and others. Most of these PTP drivers do not directly involve IEEE 1588 or networking as well. > There should be a separate class > for "hypervisor clocks", if not a common driver. 'hypervisor clock' is not very accurate. CIPU PTP can be used in VM and bare metal scenarios, and bare metals do not need hypervisors. Regards.