From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay4-d.mail.gandi.net (relay4-d.mail.gandi.net [217.70.183.196]) (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 420D91EB5D8; Fri, 30 May 2025 09:08:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.196 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748596134; cv=none; b=U9XQdV9YYkAgBBWSWwV/f25KFGrKgMHyo3oZQF5oA7HVrTEFS79SW2swJKSYGbaCV0rI3ADubUsaN+lrSa23dNNgEAaVFPntMEfFmp2wQM6z7kxCtLpwaGFHIRpZjzzS5su5S7eMpJ+M7LDzU1/VdGL/olGBTBOC0B9ElRYiRUE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748596134; c=relaxed/simple; bh=kyXdt8s0xKz4LjroE2u3gSZ0qK9QnI9kcAdnHQnzJj8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=UpT09/elycHJ4rE5KgttTEhX+isDEivw5H1K+MZFqg7K+ISSIKJVGQdu/DHdZfqhgCcHaLxXM8mbkqCYo94qYBHZGnuLnVOWshCk1PWgXRNzF831Xbfh9HaNrsSR9RK5ds3gJrmi5WrUf9OQuZVXOQl8WFNF6e+ZemD9w2yWsBE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=ZB1U/Pdf; arc=none smtp.client-ip=217.70.183.196 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="ZB1U/Pdf" Received: by mail.gandi.net (Postfix) with ESMTPSA id D06D643349; Fri, 30 May 2025 09:08:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1748596129; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=YDcQoFFC4NqCXcyobvRRuP1Ua4ytiuIE7XjIkD34fbk=; b=ZB1U/Pdfi7HtDnqYB1OWNlxulO3P8Fzu1T1afPYQ754WfHDNuOCqhr37hUY6ZczMdot6mN iKfgB57p8ne86qqiVAZL4T0zsuD2oXjkNi9Lx3+FRbgiijwLmb9ZSxZ3KK2eC8Xqd9CioZ yzOYPApcG7YNnNy58ZNYVwhc7L78+lx/W8BrCXo2NEU35lMAFE1SSpZx26hyQJVZ3Nrnmb w6+mG5x8R8W7GNQ2s81ezwluiyStYudEhpPnKiYruUKX3GhapRbICKk4/l3DWhZDNjo9ME QUFFW58toUQT05s34GNXa92rPdx7Bu+JwK3kC06Yh9cWmK4T9/7lyc5QvFJqLA== From: Romain Gantois To: "Russell King (Oracle)" Cc: Maxime Chevallier , davem@davemloft.net, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, thomas.petazzoni@bootlin.com, Andrew Lunn , Jakub Kicinski , Eric Dumazet , Paolo Abeni , linux-arm-kernel@lists.infradead.org, Christophe Leroy , Herve Codina , Florian Fainelli , Heiner Kallweit , Vladimir Oltean , =?UTF-8?B?S8O2cnk=?= Maincent , Marek =?UTF-8?B?QmVow7pu?= , Oleksij Rempel , =?UTF-8?B?Tmljb2zDsg==?= Veronese , Simon Horman , mwojtas@chromium.org, Antoine Tenart , devicetree@vger.kernel.org, Conor Dooley , Krzysztof Kozlowski , Rob Herring , Daniel Golle , Dimitri Fedrau Subject: Re: [PATCH net-next v6 06/14] net: phy: Introduce generic SFP handling for PHY drivers Date: Fri, 30 May 2025 11:08:41 +0200 Message-ID: <12687918.O9o76ZdvQC@fw-rgant> In-Reply-To: References: <20250507135331.76021-1-maxime.chevallier@bootlin.com> <6159237.lOV4Wx5bFT@fw-rgant> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart5904461.DvuYhMxLoT"; micalg="pgp-sha512"; protocol="application/pgp-signature" X-GND-State: clean X-GND-Score: -100 X-GND-Cause: gggruggvucftvghtrhhoucdtuddrgeeffedrtddtgddvkeeiudculddtuddrgeefvddrtddtmdcutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfitefpfffkpdcuggftfghnshhusghstghrihgsvgenuceurghilhhouhhtmecufedtudenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujfgurhephffvvefufffkjghfgggtsehgtderredttdejnecuhfhrohhmpeftohhmrghinhcuifgrnhhtohhishcuoehrohhmrghinhdrghgrnhhtohhishessghoohhtlhhinhdrtghomheqnecuggftrfgrthhtvghrnhephfdvleekvefgieejtdduieehfeffjefhleegudeuhfelteduiedukedtieehlefgnecuffhomhgrihhnpegsohhothhlihhnrdgtohhmnecukfhppeeltddrkeelrdduieefrdduvdejnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehinhgvthepledtrdekledrudeifedruddvjedphhgvlhhopehffidqrhhgrghnthdrlhhotggrlhhnvghtpdhmrghilhhfrhhomheprhhomhgrihhnrdhgrghnthhoihhssegsohhothhlihhnrdgtohhmpdhnsggprhgtphhtthhopeeftddprhgtphhtthhopehlihhnuhigsegrrhhmlhhinhhugidrohhrghdruhhkpdhrtghpthhtohepmhgrgihimhgvrdgthhgvvhgrlhhlihgvrhessghoohhtlhhinhdrtghomhdprhgtphhtthhopegurghvvghmsegurghvvghmlhhofhhtrdhnvghtpdhrtghpthhtohepnhgvthguvghvsehvg hgvrhdrkhgvrhhnvghlrdhorhhgpdhrtghpthhtoheplhhinhhugidqkhgvrhhnvghlsehvghgvrhdrkhgvrhhnvghlrdhorhhgpdhrtghpthhtoheplhhinhhugidqrghrmhdqmhhsmhesvhhgvghrrdhkvghrnhgvlhdrohhrghdprhgtphhtthhopehthhhomhgrshdrphgvthgriiiiohhnihessghoohhtlhhinhdrtghomhdprhgtphhtthhopegrnhgurhgvfieslhhunhhnrdgthh X-GND-Sasl: romain.gantois@bootlin.com --nextPart5904461.DvuYhMxLoT Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8"; protected-headers="v1" From: Romain Gantois To: "Russell King (Oracle)" Date: Fri, 30 May 2025 11:08:41 +0200 Message-ID: <12687918.O9o76ZdvQC@fw-rgant> In-Reply-To: MIME-Version: 1.0 On Friday, 30 May 2025 09:46:19 CEST Russell King (Oracle) wrote: > On Fri, May 30, 2025 at 09:28:11AM +0200, Romain Gantois wrote: > > On Thursday, 29 May 2025 15:23:22 CEST Russell King (Oracle) wrote: > > > On Wed, May 28, 2025 at 09:35:35AM +0200, Romain Gantois wrote: > > > > > In that regard, you can consider 1000BaseX as a MII mode (we do have > > > > > PHY_INTERFACE_MODE_1000BASEX). > > > > > > > > Ugh, the "1000BaseX" terminology never ceases to confuse me, but yes > > > > you're > > > > right. > > > > > > 1000BASE-X is exactly what is described in IEEE 802.3. It's a PHY > > > interface mode because PHYs that use SerDes can connect to the host > > > using SGMII or 1000BASE-X over the serial link. > > > > > > 1000BASE-X's purpose in IEEE 802.3 is as a protocol for use over > > > fibre links, as the basis for 1000BASE-SX, 1000BASE-LX, 1000BASE-EX > > > etc where the S, L, E etc are all to do with the properties of the > > > medium that the electrical 1000BASE-X is sent over. It even includes > > > 1000BASE-CX which is over copper cable. > > > > Ah makes sense, thanks for the explanation. I guess my mistake was > > assuming > > that MAC/PHY interface modes were necessarily strictly at the > > reconciliation sublayer level, and didn't include PCS/PMA functions. > > When a serdes protocol such as SGMII, 1000BASE-X, or 10GBASE-R is being > used with a PHY, the IEEE 802.3 setup isn't followed exactly - in > effect there are more layers. > > On the SoC: > > MAC > Reconciliation (RS) > PCS > SerDes (part of the PMA layer) > > On the PHY side of the SerDes host-to-phy link: > > SerDes > PCS (which may or may not be exposed in the PHY register set, > and is normally managed by the PHY itself) > (maybe other layers, could include MACs back-to-back) > PCS > PMA > PMD > > Hope that helps explain what's going on a little more. Definitely helps a lot, thanks. -- Romain Gantois, Bootlin Embedded Linux and Kernel engineering https://bootlin.com --nextPart5904461.DvuYhMxLoT Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part. 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