From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E996BC433EF for ; Thu, 24 Mar 2022 13:49:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350602AbiCXNvO (ORCPT ); Thu, 24 Mar 2022 09:51:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40560 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350584AbiCXNvJ (ORCPT ); Thu, 24 Mar 2022 09:51:09 -0400 Received: from mail-pg1-x536.google.com (mail-pg1-x536.google.com [IPv6:2607:f8b0:4864:20::536]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EA1741B782 for ; Thu, 24 Mar 2022 06:49:37 -0700 (PDT) Received: by mail-pg1-x536.google.com with SMTP id q19so3889109pgm.6 for ; Thu, 24 Mar 2022 06:49:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=ikm/0ZjRJewNvQ6cWOgMbpAqJSotvsfurofTtKMVK4A=; b=QHaNmZa8r3exqnPtdcsJd7MtwOIffBxpxhm2DC4Wrztpoatu46cqaELPCwm4SUZjoP eGaTvPZ94tT4p/cNL0HuDPgthCpAfzapwa42RKovG3nlenXCnL3YpSZNW6SBZB0U0pjm OA4SKPU3nfOc2kk8oqYI1mc7mdpL8lYq04+wipMddkPWoi2R4zlvsVHzo/r/AlBpJoZw Uxirm6FHsTjvDFr9/oh+ChK9vOxmnZDdNiVQvmmR9hHKCY/hAvyoR1I7r8p0V0ovQIgu hSZ5ilNtLjbY1mNzOdQcpOYqJDsEtbh5RC6nn5TUekMFc8yJ/GurJiqKpkaOUAp+9KJf MfAw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=ikm/0ZjRJewNvQ6cWOgMbpAqJSotvsfurofTtKMVK4A=; b=Z4R6Hu1zUygtSt4BWCf7vtr1gI4NLJTmEkNHjDLytrjbVTCq38el/pgwHVyiCJ6St9 GpLTUwcD/eLMVto2tWNwCiez9l3zyQixgf/4M8x1e1xI8kXKSM4dcVPhtKjpO5plY2zY 95r5qD2fGmhPPLlWZpe4Cad1+K2mZfCHUpkLXbzKLPyHr1niiBm61XHW1xIMUrBBmT7j CUFYUmlhZLAzpeSQViLZNw2Tili3CMwUf/djuL96ImCa6rmMVNeM+swaxCg6CVL8w+gR pseAtDaOl7quy9aXxNovcFBROdHzt8PrCKvsDSRADz2vQcBJnOdEq9SWh70pHXQ5VuqB VkdA== X-Gm-Message-State: AOAM530vib9Gk/kxiKMETs3d+zpUZ4QlXfvvpQI5QMiTLVKoLfSDA7GF qBC1u2UoaVesAm4mGNRIwh0= X-Google-Smtp-Source: ABdhPJz2sfQAR38yyq7HMwWgt0LTvOkXeF9spelcdsBSPH9KarJ6FKnyaRTsm8W/p4UdVMMjidJDuA== X-Received: by 2002:a63:17:0:b0:37f:f283:24b with SMTP id 23-20020a630017000000b0037ff283024bmr4146482pga.407.1648129777476; Thu, 24 Mar 2022 06:49:37 -0700 (PDT) Received: from hoboy.vegasvil.org ([2601:640:8200:33:e2d5:5eff:fea5:802f]) by smtp.gmail.com with ESMTPSA id s21-20020a63dc15000000b00378c9e5b37fsm2714090pgg.63.2022.03.24.06.49.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 24 Mar 2022 06:49:37 -0700 (PDT) Date: Thu, 24 Mar 2022 06:49:34 -0700 From: Richard Cochran To: Gerhard Engleder Cc: yangbo.lu@nxp.com, davem@davemloft.net, kuba@kernel.org, mlichvar@redhat.com, vinicius.gomes@intel.com, netdev@vger.kernel.org Subject: Re: [PATCH net-next v1 2/6] ptp: Request cycles for TX timestamp Message-ID: <20220324134934.GB27824@hoboy.vegasvil.org> References: <20220322210722.6405-1-gerhard@engleder-embedded.com> <20220322210722.6405-3-gerhard@engleder-embedded.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220322210722.6405-3-gerhard@engleder-embedded.com> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue, Mar 22, 2022 at 10:07:18PM +0100, Gerhard Engleder wrote: > The free running time of physical clocks called cycles shall be used for > hardware timestamps to enable synchronisation. > > Introduce new flag SKBTX_HW_TSTAMP_USE_CYCLES, which signals driver to > provide a TX timestamp based on cycles if cycles are supported. > > Signed-off-by: Gerhard Engleder > --- > include/linux/skbuff.h | 3 +++ > net/core/skbuff.c | 2 ++ > net/socket.c | 10 +++++++++- > 3 files changed, 14 insertions(+), 1 deletion(-) > > diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h > index 26538ceb4b01..f494ddbfc826 100644 > --- a/include/linux/skbuff.h > +++ b/include/linux/skbuff.h > @@ -578,6 +578,9 @@ enum { > /* device driver is going to provide hardware time stamp */ > SKBTX_IN_PROGRESS = 1 << 2, > > + /* generate hardware time stamp based on cycles if supported */ > + SKBTX_HW_TSTAMP_USE_CYCLES = 1 << 3, Bit 4 used, but 3 was unused... interesting! > /* generate wifi status information (where possible) */ > SKBTX_WIFI_STATUS = 1 << 4, > > diff --git a/net/core/skbuff.c b/net/core/skbuff.c > index 10bde7c6db44..c0f8f1341c3f 100644 > --- a/net/core/skbuff.c > +++ b/net/core/skbuff.c > @@ -4847,6 +4847,8 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb, > skb_shinfo(skb)->tx_flags |= skb_shinfo(orig_skb)->tx_flags & > SKBTX_ANY_TSTAMP; > skb_shinfo(skb)->tskey = skb_shinfo(orig_skb)->tskey; > + } else { > + skb_shinfo(skb)->tx_flags &= ~SKBTX_HW_TSTAMP_USE_CYCLES; > } > > if (hwtstamps) > diff --git a/net/socket.c b/net/socket.c > index 982eecad464c..1acebcb19e8f 100644 > --- a/net/socket.c > +++ b/net/socket.c > @@ -683,9 +683,17 @@ void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags) > { > u8 flags = *tx_flags; > > - if (tsflags & SOF_TIMESTAMPING_TX_HARDWARE) > + if (tsflags & SOF_TIMESTAMPING_TX_HARDWARE) { > flags |= SKBTX_HW_TSTAMP; > > + /* PTP hardware clocks can provide a free running time called > + * cycles as base for virtual clocks. "PTP hardware clocks can provide a free running cycle counter as a time base for virtual clocks." Thanks, Richard