From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gloria.sntech.de (gloria.sntech.de [185.11.138.130]) (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 8AAAF3C09ED; Fri, 9 Oct 2026 07:19:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.11.138.130 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791530378; cv=none; b=McyjPYuoTuFMfbFAl7ZD6U+n9rxkVtQRBrywayWnAp0K64wc6h4a6NouhROwhZAAiFaCuAnVCgwBEhk/TjBpYiVqk+H8R9IiPLJ0dx65PMfJWTcerEEq5hZOfbySWnsXXLIQoiSrrQzsA8vtKhRO59bT8o53o3lVzxZQjvXHSFA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791530378; c=relaxed/simple; bh=WI37INvaBEZu19Y1qkoX78S346Q/Pw5Ut3F28r07uck=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=qOA3PqJgTav1T0LZ/fEVMUGaMGXfmBA6CoWMLXl5qf1A/+eBiR3xCgUe+AF+upxHk3ifRHULtLB/9AjGFg+FJyBz5qSbXZPvtqum/eSWwKWMWPeEY+9Af7qyS/40Lfi0nV+LXsAJptkmlq//xjSwV3P7na1nmSUcDwIe9xYVfs4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=sntech.de; spf=pass smtp.mailfrom=sntech.de; dkim=pass (2048-bit key) header.d=sntech.de header.i=@sntech.de header.b=dasyinXg; arc=none smtp.client-ip=185.11.138.130 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=sntech.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sntech.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=sntech.de header.i=@sntech.de header.b="dasyinXg" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sntech.de; s=gloria202408; h=Content-Type:Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Reply-To; bh=a/8J9ffRImKtNVgXRfCWQ7IuyliYAcjl+4vVSs1mp0o=; b=dasyinXg5c5YC9V8raqDWPImHP ZLaFAtOqeK/6eFGh99ixvboc5TRLL4LqbmI83EQEC7yFDUW7RbfmU8fWQ0h5F3wzWB/ocDRdNs7aU Mx25M1ZiXFRP1B6KsiQmYb88Yti+hdeSgb1L7I8v113gqBReOZBgVKmBp2EALwVl4oLP/4ALmSojt wdeRs8PbtPMCKyKtrLMTm8ifBggbc33keCoyCkodt+ugxhgxlLjIceV1drs09ZBSrlrY0X1rxJDQQ /MO/n3RG9Eqp8/LNKzwfQDYdUR21ZO8UCSiwjXYwbucVhOS5frUaE7RK4OTyXFa/GhNdiofR7KSzX 9kiqAF+Q==; From: Heiko Stuebner To: Rob Herring , Krzysztof Kozlowski , Conor Dooley , Liang Chen , Jun Yan Cc: Jun Yan , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] arm64: dts: rockchip: Add dma-names to RK356x UART nodes Date: Fri, 09 Oct 2026 09:19:25 +0200 Message-ID: <3055334.SvYEEZNnvj@phil> In-Reply-To: <20261009020103.364498-1-jerrysteve1101@gmail.com> References: <20261009020103.364498-1-jerrysteve1101@gmail.com> Precedence: bulk X-Mailing-List: devicetree@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" Am Freitag, 9. Oktober 2026, 04:01:02 Mitteleurop=C3=A4ische Sommerzeit sch= rieb Jun Yan: > The RK356x UART nodes define a dmas property but omit the matching > dma-names property, so the 8250 driver fails to request a DMA channel > and falls back to PIO, logging: >=20 > of_dma_request_slave_channel: dma-names property of node > '/serial@fe650000' missing or empty >=20 > Add the missing dma-names =3D "tx", "rx" to uart0 through uart9, > matching other Rockchip SoCs such as the RK3588. >=20 > Fixes: a3adc0b9071d ("arm64: dts: rockchip: add core dtsi for RK3568 SoC") > Signed-off-by: Jun Yan Please don't do that. Uart dma can cause problems on uarts that don't use flow-control, see [0]. So the solution of choice is to only enable it for uarts connected to bluetooth on at least RK356x. Heiko [0] https://lore.kernel.org/linux-rockchip/CAMdYzYpXtMocCtCpZLU_xuWmOp2Ja_v= 0Aj0e6YFNRA-yV7u14g@mail.gmail.com/