From patchwork Thu Oct 31 09:29:51 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 840003 Received: from baptiste.telenet-ops.be (baptiste.telenet-ops.be [195.130.132.51]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DE562197A88 for ; Thu, 31 Oct 2024 09:30:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=195.130.132.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730367038; cv=none; b=Kd4q+YV9XwMVKfBnB3Hr48ix0eBhkNS3dvQlVI890tzC9N2Ef+rMLdWOXwjhTk71yuLxWCW+qqEakixfBNfqbqzFC+k0qBWtNoyvJebORMdwylij0J3TVIwkygUoOP8mhPBtr/AUtIcGZYuPkaBHWUUKBwpbzRP9GZLi99r4sUo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730367038; c=relaxed/simple; bh=LqFBcy9hztpUu09vXwjLp/XdqpMKV3U2koopuxf6JEo=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version:Content-Type; b=fo5aA7/D++8Ms3vZbJ0Ax/g8ymH9277YDb36iFgFDBYE8wVOjAmSjyGFJoY+0+c/RTuby8vsS91XlQ+n29Jb0UOFkTutHl8GSrG5ryqu5RHdwdrzzFL6REdVzBwCJP2JGVKIaLIojHtIyfp0zbA7a6V3+q6hm5Z+TZj0YMIpUCY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=glider.be; spf=none smtp.mailfrom=linux-m68k.org; arc=none smtp.client-ip=195.130.132.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=glider.be Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux-m68k.org Received: from ramsan.of.borg ([IPv6:2a02:1810:ac12:ed80:ceb8:3fda:3601:820f]) by baptiste.telenet-ops.be with cmsmtp id WxWS2D0094BbGPD01xWSpB; Thu, 31 Oct 2024 10:30:26 +0100 Received: from rox.of.borg ([192.168.97.57]) by ramsan.of.borg with esmtp (Exim 4.95) (envelope-from ) id 1t6RVG-0061eS-VM; Thu, 31 Oct 2024 10:30:25 +0100 Received: from geert by rox.of.borg with local (Exim 4.95) (envelope-from ) id 1t6RV3-006hZj-2d; Thu, 31 Oct 2024 10:29:53 +0100 From: Geert Uytterhoeven To: Tony Lindgren , Kevin Hilman , Roger Quadros , Robert Nelson , Colin Foster Cc: linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Geert Uytterhoeven Subject: [PATCH] ARM: dts: am335x-bone-common: Increase MDIO reset deassert delay to 50ms Date: Thu, 31 Oct 2024 10:29:51 +0100 Message-Id: <9002a58daa1b2983f39815b748ee9d2f8dcc4829.1730366936.git.geert+renesas@glider.be> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-omap@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Commit b9bf5612610aa7e3 ("ARM: dts: am335x-bone-common: Increase MDIO reset deassert time") already increased the MDIO reset deassert delay from 6.5 to 13 ms, but this may still cause Ethernet PHY probe failures: SMSC LAN8710/LAN8720 4a101000.mdio:00: probe with driver SMSC LAN8710/LAN8720 failed with error -5 On BeagleBone Black Rev. C3, ETH_RESETn is controlled by an open-drain AND gate. It is pulled high by a 10K resistor, and has a 4.7µF capacitor to ground, giving an RC time constant of 47ms. As it takes 0.7RC to charge the capacitor above the threshold voltage of a CMOS input (VDD/2), the delay should be at least 33ms. Considering the typical tolerance of 20% on capacitors, 40ms would be safer. Add an additional safety margin and settle for 50ms. Signed-off-by: Geert Uytterhoeven Reviewed-by: Kevin Hilman Tested-by: Kevin Hilman --- arch/arm/boot/dts/ti/omap/am335x-bone-common.dtsi | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/boot/dts/ti/omap/am335x-bone-common.dtsi b/arch/arm/boot/dts/ti/omap/am335x-bone-common.dtsi index a0fb431aec8411d8..212d7f867f8786af 100644 --- a/arch/arm/boot/dts/ti/omap/am335x-bone-common.dtsi +++ b/arch/arm/boot/dts/ti/omap/am335x-bone-common.dtsi @@ -409,7 +409,7 @@ ethphy0: ethernet-phy@0 { /* Support GPIO reset on revision C3 boards */ reset-gpios = <&gpio1 8 GPIO_ACTIVE_LOW>; reset-assert-us = <300>; - reset-deassert-us = <13000>; + reset-deassert-us = <50000>; }; };