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 6E3C833A9C5; Fri, 23 Jan 2026 10:12:21 +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=1769163141; cv=none; b=RjnooO3OawixJOILY+Gtd786ijMKapOOaWFC2poUxLIjO1eTqZjldGDWBjMpw/8R8q1WYJxvLQqSdfy5I/4hceE3RgE++W/tvyU1P94OHNUmN/b3CSAWHhU7HJEK2MLBNMSLCedUv2sWlL1DzExxWi9ElY+ZSrMxa4GoqFc7i5E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769163141; c=relaxed/simple; bh=Rs3+J9vly3EX1QkycoNIipTzcrq6Sl9s200nzYCGxDY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=JmaqAYTZgvS5PFH6T8vTXLOukE+QgXU+nToxqJMljR7efTYChmYH2OBv33oaNCaOdCZvPAJ4fhvqI7tWzA6z0XSrJ7bF+QyIZadTuv1seS3hYBBQUYF+TNgUfF1iA5ttCR/VtgRvDOCOuBX49SP6R6kjqt/y/luwSqEcn5vXrqo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=cj/LdxF3; 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="cj/LdxF3" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 36331C4CEF1; Fri, 23 Jan 2026 10:12:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1769163141; bh=Rs3+J9vly3EX1QkycoNIipTzcrq6Sl9s200nzYCGxDY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=cj/LdxF3Fsu/SGpfZdF24FP4C+lzIKjq8qs6dXzoJaYBJnE/rzc13e6W1vCJ37Mo1 c1m66pANSmZviUS51kES2Twe5cI02pyI0AmT2EDqgFl7yHfHfh9iCVn75r54XCVzFm iTD+BJJCjXra/jnzCidwJ/DrItSo79TZifqu4rjUiSkqpJA+aJEUtuPYDbDxK89lno N0d7MteUWt1jAldAVfFr/qgPVy5hOwJUfTAAMBYI+hfp6Z4YePli/K/j33Xkx7/oUJ vBCOx7Ul1+5Ge7O3Nrzz4O4cbFdyybkmRY2u72jiIVaW4vw7iZ5rK8kITbXr7CPF1r nTxLaC/MZ6ptw== Date: Fri, 23 Jan 2026 10:12:15 +0000 From: Simon Horman To: Bastien Curutchet Cc: Woojung Huh , UNGLinuxDriver@microchip.com, Andrew Lunn , Vladimir Oltean , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Richard Cochran , Pascal Eberhard , =?utf-8?Q?Miqu=C3=A8l?= Raynal , Thomas Petazzoni , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net-next 5/8] net: dsa: microchip: Add KSZ8463 tail tag handling Message-ID: References: <20260115-ksz8463-ptp-v1-0-bcfe2830cf50@bootlin.com> <20260115-ksz8463-ptp-v1-5-bcfe2830cf50@bootlin.com> <4f36ca91-9749-4502-bc30-838238d24ba3@bootlin.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4f36ca91-9749-4502-bc30-838238d24ba3@bootlin.com> On Thu, Jan 22, 2026 at 01:59:21PM +0100, Bastien Curutchet wrote: > Hi Simon, > > On 1/20/26 6:17 PM, Simon Horman wrote: > > On Thu, Jan 15, 2026 at 04:57:04PM +0100, Bastien Curutchet (Schneider Electric) wrote: > > > KSZ8463 uses the KSZ9893 DSA TAG driver. However, the KSZ8463 doesn't > > > use the tail tag to convey timestamps to the host as KSZ9893 does. It > > > uses the reserved fields in the PTP header instead. > > > > > > Add a KSZ8463-specifig DSA_TAG driver to handle KSZ8463 timestamps. > > > There is no information in the tail tag to distinguish PTP packets from > > > others so use the ptp_classify_raw() helper to find the PTP packets and > > > extract the timestamp from their PTP headers. > > > > > > Signed-off-by: Bastien Curutchet (Schneider Electric) > > > > ... > > > > > diff --git a/net/dsa/tag_ksz.c b/net/dsa/tag_ksz.c > > > index 9170a0148cc43b4213ec4bd8e81d338589671f23..635679402f8a96b29536a91988346a8825bae976 100644 > > > --- a/net/dsa/tag_ksz.c > > > +++ b/net/dsa/tag_ksz.c > > > @@ -16,6 +16,7 @@ > > > #define KSZ9477_NAME "ksz9477" > > > #define KSZ9893_NAME "ksz9893" > > > #define LAN937X_NAME "lan937x" > > > +#define KSZ8463_NAME "ksz8463" > > > /* Typically only one byte is used for tail tag. */ > > > #define KSZ_PTP_TAG_LEN 4 > > > @@ -383,6 +384,108 @@ static const struct dsa_device_ops ksz9893_netdev_ops = { > > > DSA_TAG_DRIVER(ksz9893_netdev_ops); > > > MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893, KSZ9893_NAME); > > > +#define KSZ8463_TAIL_TAG_PRIO GENMASK(4, 3) > > > +#define KSZ8463_TAIL_TAG_EG_PORT_M GENMASK(2, 0) > > > + > > > +static void ksz8463_xmit_timestamp(struct dsa_port *dp, struct sk_buff *skb) > > > +{ > > > + struct ksz_tagger_private *priv; > > > + struct ptp_header *ptp_hdr; > > > + unsigned int ptp_type; > > > + u32 tstamp_raw = 0; > > > + s64 correction; > > > + > > > + priv = ksz_tagger_private(dp->ds); > > > + > > > + if (!test_bit(KSZ_HWTS_EN, &priv->state)) > > > + return; > > > + > > > + if (!KSZ_SKB_CB(skb)->update_correction) > > > + return; > > > + > > > + ptp_type = KSZ_SKB_CB(skb)->ptp_type; > > > + ptp_hdr = ptp_parse_header(skb, ptp_type); > > > + if (!ptp_hdr) > > > + return; > > > + > > > + correction = (s64)get_unaligned_be64(&ptp_hdr->correction); > > > + > > > + if (correction < 0) { > > > + struct timespec64 ts; > > > + > > > + ts = ns_to_timespec64(-correction >> 16); > > > + tstamp_raw = ((ts.tv_sec & 3) << 30) | ts.tv_nsec; > > > + > > > + ptp_hdr->reserved2 = tstamp_raw; > > > > I think that you need to assign a be32 rather than a u32 to reserved2. > > > > Indeed. By testing this back, I realize that this is only needed by the > one-step mode. This series only adds support for two-step so I'll just > remove this part. Great, thanks.