From nobody Thu Oct 2 10:55:22 2025 Received: from finn.localdomain (finn.gateworks.com [108.161.129.64]) (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 9B467314B84; Thu, 18 Sep 2025 15:45:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=108.161.129.64 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758210311; cv=none; b=k8P9zOdFP8LexXBPl9kAbqqCHRGG7qCOChNfnVfJDo4h8XfQS3KpH/Dr6i3ySg3CHKSoTJah+m6scifsWa/7Dw72ESrpaA+24U+ZljgTDqJOLuB8nSs591kgJnT+8w5LtHnk/HQK7SiIeuELzfCjsgnViF2XJA6Vh/rKG9ml+Hk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758210311; c=relaxed/simple; bh=bm8hHyQemjiUmvDQCawOnSDA0FHUe7wJgTnpKvnzYJ8=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=nPVHyUh0tRDsXIOz3G/3i9YuVDMHz6uKBekUIZfoBYBzqifhVFdi+72R22gfSzOzXoM5wIA8hzWgkIvIBweGqbt/rWv3RoyYCK4FdJug3M9aKpYRdEMP1rYewqqNeBDFtRT+l9+Qmv8fh65JDuBnTRc3CaUsobrhjQT+BOLtwLc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gateworks.com; spf=pass smtp.mailfrom=gateworks.com; arc=none smtp.client-ip=108.161.129.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gateworks.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gateworks.com Received: from syn-068-189-091-139.biz.spectrum.com ([68.189.91.139] helo=tharvey.pdc.gateworks.com) by finn.localdomain with esmtp (Exim 4.95) (envelope-from ) id 1uzGoa-00B1eF-QM; Thu, 18 Sep 2025 15:44:56 +0000 From: Tim Harvey To: Rob Herring , Krzysztof Kozlowski , Conor Dooley , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam Cc: devicetree@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Tim Harvey Subject: [PATCH v2 4/7] arm64: dts: imx8mm-venice-gw700x: reduce RGMII CLK drive strength Date: Thu, 18 Sep 2025 08:44:48 -0700 Message-Id: <20250918154451.2531802-5-tharvey@gateworks.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20250918154451.2531802-1-tharvey@gateworks.com> References: <20250918154451.2531802-1-tharvey@gateworks.com> 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 Content-Type: text/plain; charset="utf-8" The i.MX8M Mini FEC RGMII tracelength is less than 1in and does not require a x6 drive strength. Reduce the CLK drive strength to x1 for lower emissions. Additionally since TXC is not a high frequency clock, use slow slew rate (FSEL=3D0) for lower emmissions and improved signal quality. Signed-off-by: Tim Harvey Reviewed-by: Peng Fan --- v2: add FSEL detail to log (Peng) --- arch/arm64/boot/dts/freescale/imx8mm-venice-gw700x.dtsi | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/boot/dts/freescale/imx8mm-venice-gw700x.dtsi b/arch= /arm64/boot/dts/freescale/imx8mm-venice-gw700x.dtsi index baf46fe28133..dca213c85cc3 100644 --- a/arch/arm64/boot/dts/freescale/imx8mm-venice-gw700x.dtsi +++ b/arch/arm64/boot/dts/freescale/imx8mm-venice-gw700x.dtsi @@ -446,7 +446,7 @@ MX8MM_IOMUXC_ENET_RD3_ENET1_RGMII_RD3 0x91 MX8MM_IOMUXC_ENET_RD2_ENET1_RGMII_RD2 0x91 MX8MM_IOMUXC_ENET_RD1_ENET1_RGMII_RD1 0x91 MX8MM_IOMUXC_ENET_RD0_ENET1_RGMII_RD0 0x91 - MX8MM_IOMUXC_ENET_TXC_ENET1_RGMII_TXC 0x1f + MX8MM_IOMUXC_ENET_TXC_ENET1_RGMII_TXC 0x0 MX8MM_IOMUXC_ENET_RXC_ENET1_RGMII_RXC 0x91 MX8MM_IOMUXC_ENET_RX_CTL_ENET1_RGMII_RX_CTL 0x91 MX8MM_IOMUXC_ENET_TX_CTL_ENET1_RGMII_TX_CTL 0x1f --=20 2.25.1