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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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250530_020853_817792_B3E9E890 X-CRM114-Status: GOOD ( 24.77 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org --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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