From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.tipi-net.de (mail.tipi-net.de [194.13.80.246]) (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 097B03E715E for ; Tue, 9 Jun 2026 08:32:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=194.13.80.246 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780993933; cv=none; b=KGiL8g4azoJTnLe/h9Rj9rt0NxLx6oQOQZeJGMu+GILAG25UMEqjxwamel/UJQdTVYOls5paQOEES7Ks6kjBkVELokQDLafTNSjFDwgl+f8hvhEEldVthaqGAqGEwW4rjhpdGU1nevNv4xYqdIOomc2aG9ZPetZMiprJX94qQZw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780993933; c=relaxed/simple; bh=1+IAERIw/yXCjdjyCVhLGK4z9evSIoeRAneiijVgqN0=; h=MIME-Version:Date:From:To:Cc:Subject:In-Reply-To:References: Message-ID:Content-Type; b=I5WO2SLxRkN4Mr6kHEenQtXcKaG5ibChziSfnpBgClgpEygwPg1kjTAhvX6ZMW5ZAJkYj9otrANSPZ8O1DM1fXnaDtVuX7gF5+A786E5Mx4pkw3aHoOHiWPa3KHjNY8Z/e+C9MOd8CYL7QcOAwHk97VFkh7fiDgkIV4SBcAk8hM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=tipi-net.de; spf=pass smtp.mailfrom=tipi-net.de; dkim=pass (2048-bit key) header.d=tipi-net.de header.i=@tipi-net.de header.b=bbs7nvkT; arc=none smtp.client-ip=194.13.80.246 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=tipi-net.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=tipi-net.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=tipi-net.de header.i=@tipi-net.de header.b="bbs7nvkT" Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id D685DA01B5; Tue, 9 Jun 2026 10:32:01 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tipi-net.de; s=dkim; t=1780993922; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:in-reply-to:references; bh=1+IAERIw/yXCjdjyCVhLGK4z9evSIoeRAneiijVgqN0=; b=bbs7nvkTL+UGRXGtM/m88YL3j1heu6S/2DlW0cAPYcGUO4/Y6u4ifQPhhB7DPLlfeOIe6v g881nIN6aXd8U8C8DMM3QOBSc5nsL92agUQWdHIgbjJkdjjtlEg2oNa8PZBRYlqIQhu7Pf tmLWOcWi5mdSDdCSNGUTPCaTG1wCw64ZgugwUbpgSWTcoyqQ5p71vo+I0wtIR9x85/inwK wq0RB2mhFcffkn4dvSk5NALOrkk3mz67hBvvMMddWW6bHaDKIwyiO1vLBoSks3W6pBrA6V pVBy5kYfQAx0Tsgn9iAEYBUkZEWu/9C4QxfCUUGdejRQaXJPS/uq3On2LNBW5A== Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Date: Tue, 09 Jun 2026 10:32:00 +0200 From: Nicolai Buchwitz To: Andrew Lunn , Janpieter Sollie Cc: netdev@vger.kernel.org Subject: Re: SFP/MDIO/I2C: help requested unlocking a SFP+ MCU to expose PHY In-Reply-To: <903daf32-aecd-4160-8f69-4fc329fdad3f@lunn.ch> References: <903daf32-aecd-4160-8f69-4fc329fdad3f@lunn.ch> Message-ID: <582a4a1181bf110e97d8d2d249dbd42a@tipi-net.de> X-Sender: nb@tipi-net.de Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit X-Last-TLS-Session-Version: TLSv1.3 Hi Andrew + Janpieter On 5.6.2026 18:51, Andrew Lunn wrote: > [...] > Do you know what MCU is in the SFP? Is there a data sheet for it? Can > you read out the EEPROM holding its code over the I2C bus? You can > then disassemble/decompile the code and see what it is actually doing. It put up a bit of a fight, but in the end I managed to take it apart. uC seems to be a GD32E230F8 [1] [2]. [1] https://www.keil.arm.com/devices/gigadevice-gd32e230f8/boards/ [2] https://odly.de/lkml/10gtek-sfp-phy.jpg Regards Nicolai