From nobody Thu Sep 24 13:39:01 2026 Received: from mx.nabladev.com (mx.nabladev.com [178.251.229.89]) (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 1F0D717C203; Thu, 24 Sep 2026 00:31:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=178.251.229.89 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790209918; cv=none; b=eHMriGoNxJ+v0CjXwPC4thuDAkI6aRC9bLUOh4HiuK5bsZnqyvk2nX60rXN5Wvb0mGYsGjUsf4++MCEzP24JrZYoIEC8xMT1SlBOQoqKwPNKH2Hf47XgBYuaaFW4WLKLQbXEFEkalr0FG+uifcGo7X+f+/I5Ow18yBCENOt8vdM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790209918; c=relaxed/simple; bh=DCMEs3W/VY9ntGtGNtRm+QaGtpqva0uHRx6sySBE5DY=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=rLcFa0lzg2BlALCp/nf0X0GD/Lzfnx5cGS3+JbQE0ctoV+VUow1BLmyzjXHQlMshwYgYxSELopCJyQAys4I74oHTS2ULzqLunCGiHM56w6m//Fds20/j7HDwPnJLtcjtn3GxZx5lOLpKKui7+sjmwYCqWxOF+qEti9Mf+N9PA18= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nabladev.com; spf=pass smtp.mailfrom=nabladev.com; dkim=pass (2048-bit key) header.d=nabladev.com header.i=@nabladev.com header.b=AaFv279O; arc=none smtp.client-ip=178.251.229.89 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nabladev.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=nabladev.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=nabladev.com header.i=@nabladev.com header.b="AaFv279O" Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id B0F49105B30; Thu, 24 Sep 2026 02:31:45 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nabladev.com; s=dkim; t=1790209908; h=from:subject:date:message-id:to:cc:mime-version: content-transfer-encoding; bh=bIla9WS4q+EH9bLUK0Yr9DxP2K0ikL42KF8TxnynahA=; b=AaFv279O1b+ULW+bBqdyq61KQtVnenL1ph3J2jqSt/cCwSHMDFPNlRUVxucWK/3m6WmELU wKeKNoeMBKChrJgNqj8VJGVsH5d44g1rwJ+xy7GCNS3z03zAVo0PjNRBFcYwkj11+Jhl5T vnW9IU7uLENe4rkH9+o1hxTgDBuDF/JhNynmw9ktP/48th9pQa8ehYsNdFZAaMIrIWw6ju 4Db34FzzCPnjCp4+FpG9N4HFcZlLx9WoUkwUmAtE77Pk/rYp4plPPxWF1iHrW8/qTNRUxg hCs1mJSJY72sqptLSRsuFRLXuHIy9/SsP7Z4rzl0TREBokgqMIKu4zjJpceB3Q== From: Marek Vasut To: netdev@vger.kernel.org Cc: Marek Vasut , "David S. Miller" , Andrew Lunn , Clark Wang , Claudiu Manoil , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Vladimir Oltean , Wei Fang , imx@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [net-next,PATCH v1] enetc: Increase eMDIO MDC rate to 1.2 MHz Date: Thu, 24 Sep 2026 02:30:59 +0200 Message-ID: <20260924003132.580306-1-marex@nabladev.com> X-Mailer: git-send-email 2.53.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Last-TLS-Session-Version: TLSv1.3 Content-Type: text/plain; charset="utf-8" The current eMDIO MDC rate is 558 kHz on i.MX95 B0. This is very low, but also very compatible. However, for example NXP TJA1120 PHY needs at minimum 1 MHz MDC clock and 558 kHz does not work with that PHY. As a minimum change, increase the MDC clock to 1.2 MHz which should be equally very compatible, since even old PHYs like LAN8210Ai, KSZ8794, DP83822 support up to 2.5 MHz MDC clock frequency, and it covers the NXP TJA1120 as well. There is no known rationale for why the 558 kHz was picked when the eMDIO driver was added. Signed-off-by: Marek Vasut --- Cc: "David S. Miller" Cc: Andrew Lunn Cc: Clark Wang Cc: Claudiu Manoil Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Paolo Abeni Cc: Vladimir Oltean Cc: Wei Fang Cc: imx@lists.linux.dev Cc: linux-kernel@vger.kernel.org Cc: netdev@vger.kernel.org --- NOTE: Alternatively, I can either add a DT property to configure the clock rate, or model the clock as clock hw divider and then use assigned-clock-rates DT property to configure the desired rate? --- drivers/net/ethernet/freescale/enetc/enetc_mdio.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc_mdio.c b/drivers/ne= t/ethernet/freescale/enetc/enetc_mdio.c index 998aaa394e9c4..30ea91cea00e5 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc_mdio.c +++ b/drivers/net/ethernet/freescale/enetc/enetc_mdio.c @@ -24,7 +24,7 @@ =20 #define ENETC_EMDIO_CFG \ (MDIO_CFG_HOLD(2) | \ - MDIO_CFG_CLKDIV(258) | \ + MDIO_CFG_CLKDIV(138) | \ MDIO_CFG_NEG) =20 #define MDIO_CTL_DEV_ADDR(x) ((x) & 0x1f) --=20 2.53.0