From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.tq-group.com (mx1.tq-group.com [93.104.207.81]) (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 2C76552F6F for ; Mon, 8 Apr 2024 10:14:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=93.104.207.81 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712571275; cv=none; b=AwgodAJYjT6tHXp2DuV1Hxnk45rOAxMOk9dAZxGH95r97X+2M53POyH6oRaxO646QNNetfx+DXQODifG810sbBYRKrtNx6BtSYU6S93YPyvQnQN7cBq2WTR2EjTms5nq+eBLRjZ3GVlCwfHpa4SHd+JVQyp4BHn4bLsv0u7bfxc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712571275; c=relaxed/simple; bh=S2e+x9biH4AfHss0WzT07+D8Pd+Nkq+00oYDUxU4lkM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=PT4QiOus2RVlCyegfOhoZFPJB0azJ9lYjAenmvrMSeo6lVUisA8NvA03KHS0WbW+PZAl+bzRFmEikry9GYV+Sq1ZsDauFgCKMlmL2NqlkbapLuVhlt8rqjy7Fa0+6WK0CXNvl8kQjy9r4/mZmU8yCGoekPTmmoheyWUDD8FqyDs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ew.tq-group.com; spf=pass smtp.mailfrom=ew.tq-group.com; dkim=pass (2048-bit key) header.d=tq-group.com header.i=@tq-group.com header.b=aWzP7p7B; dkim=fail (0-bit key) header.d=ew.tq-group.com header.i=@ew.tq-group.com header.b=XJCrKROH reason="key not found in DNS"; arc=none smtp.client-ip=93.104.207.81 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ew.tq-group.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ew.tq-group.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=tq-group.com header.i=@tq-group.com header.b="aWzP7p7B"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=ew.tq-group.com header.i=@ew.tq-group.com header.b="XJCrKROH" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tq-group.com; i=@tq-group.com; q=dns/txt; s=key1; t=1712571272; x=1744107272; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=rs0Fk9cEZOdXF0db2/Mxr5B0/nzyKRMXHR0l9+QBUz8=; b=aWzP7p7BVrV6xCq7J9JB1Im43Fsgf2wzd8sP85MFFn9O8NuginbxD+gw QIvdWfQuev+/yV51rfA5gni0kjmnhQIxVwfeYPfovYHB+tz59CE2vxuLg abm1Hz3vZVBtbM7d9T53jGyGasNdTrq8JfTd0qy+8k4e4C9FGq/oq79k4 8AZp4TRCJEJ1RG5JSMjdgxMpNxAotQHMnvnmGQnBV3eSWQSAdN6nsmOBz Tntjgny1VQmAD9Wh/XoK2AVociJ+jMjpN6hwI0iYcDrhsar/Nlp0AY7Xu LRQejufiBPNZnuzJtX6OR0IWyFbxZ/Pn4Eh1m+1aqYovru+ajkKugiWmu Q==; X-IronPort-AV: E=Sophos;i="6.07,186,1708383600"; d="scan'208";a="36293913" Received: from vmailcow01.tq-net.de ([10.150.86.48]) by mx1.tq-group.com with ESMTP; 08 Apr 2024 12:14:24 +0200 Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 9E929160CBC; Mon, 8 Apr 2024 12:14:18 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ew.tq-group.com; s=dkim; t=1712571260; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:in-reply-to:references; bh=rs0Fk9cEZOdXF0db2/Mxr5B0/nzyKRMXHR0l9+QBUz8=; b=XJCrKROH2TfNQokiLhiogbx9Kt1LLyBnFjYKV0udAwBIeuD5xMEyL84fDOTM28NLzx2WB1 Av+JRXF/mTMHiI1oVmPU5YH0im1/CRMsHUs5iiI5zURCJAVlSk4EfnCpVlXW02fuqlZk/s 97T94wCUxzJcux32wuhz/ELeGysGZxSKpMoIkA7yE/U6IBtR9A91eHRf9pta3yitvX8+w9 GtqN37pCBg86DlFs6gMaas6zazfi+ZcZNp+GmnxtrnB0rizoQlNvCXQ+R5PpzeS/ZWcTkK hxaD5IsEudmIaVWrRu0n6Nrd0DpUyNQWBZCz4qg4SsLyznp92+WitOxg9gzySA== From: Alexander Stein To: Adam Ford , Laurent Pinchart , linux-arm-kernel@lists.infradead.org Cc: linux-arm-kernel@lists.infradead.org, Conor Dooley , Fabio Estevam , Krzysztof Kozlowski , Paul Elder , Pengutronix Kernel Team , Rob Herring , Sascha Hauer , Shawn Guo , devicetree@vger.kernel.org, imx@lists.linux.dev, Marek Vasut Subject: Re: [PATCH] arm64: dts: imx8mp: Align both CSI2 pixel clock Date: Mon, 08 Apr 2024 12:14:18 +0200 Message-ID: <5771435.DvuYhMxLoT@steina-w> Organization: TQ-Systems GmbH In-Reply-To: <8c1935d1-7f59-4742-9659-bf87ac4b736c@denx.de> References: <20240405202243.46278-1-marex@denx.de> <8c1935d1-7f59-4742-9659-bf87ac4b736c@denx.de> 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" X-Last-TLS-Session-Version: TLSv1.3 Hi everyone, Am Samstag, 6. April 2024, 04:58:39 CEST schrieb Marek Vasut: > On 4/5/24 11:04 PM, Adam Ford wrote: > > On Fri, Apr 5, 2024 at 3:43=E2=80=AFPM Laurent Pinchart > > wrote: > >> > >> Hi Marek, > >> > >> (CC'ing Adam) > >> > >> Thank you for the patch. > >> > >> On Fri, Apr 05, 2024 at 10:22:26PM +0200, Marek Vasut wrote: > >>> Configure both CSI2 assigned-clock-rates the same way. > >>> There does not seem to be any reason for keeping the > >>> two CSI2 pixel clock set to different frequencies. > >> > >> There's an issue when using two cameras concurrently. This has been > >> discussed some time ago on the linux-media mailing list, see [1]. Adam > >> knows more than I do on this topic. > >> > >> [1] https://lore.kernel.org/linux-media/CAHCN7x+kymRGO2kxvN2=3DzLiqRjf= Tc3hdf3VdNVkWjsW3La0bnA@mail.gmail.com/ > >> > >>> Signed-off-by: Marek Vasut > >>> --- > >>> Cc: Conor Dooley > >>> Cc: Fabio Estevam > >>> Cc: Krzysztof Kozlowski > >>> Cc: Laurent Pinchart > >>> Cc: Paul Elder > >>> Cc: Pengutronix Kernel Team > >>> Cc: Rob Herring > >>> Cc: Sascha Hauer > >>> Cc: Shawn Guo > >>> Cc: devicetree@vger.kernel.org > >>> Cc: imx@lists.linux.dev > >>> Cc: linux-arm-kernel@lists.infradead.org > >>> --- > >>> arch/arm64/boot/dts/freescale/imx8mp.dtsi | 2 +- > >>> 1 file changed, 1 insertion(+), 1 deletion(-) > >>> > >>> diff --git a/arch/arm64/boot/dts/freescale/imx8mp.dtsi b/arch/arm64/b= oot/dts/freescale/imx8mp.dtsi > >>> index 1bb96e96639f2..2e9ce0c3a9815 100644 > >>> --- a/arch/arm64/boot/dts/freescale/imx8mp.dtsi > >>> +++ b/arch/arm64/boot/dts/freescale/imx8mp.dtsi > >>> @@ -1703,7 +1703,7 @@ mipi_csi_1: csi@32e50000 { > >>> <&clk IMX8MP_CLK_MED= IA_MIPI_PHY1_REF>; > >>> assigned-clock-parents =3D <&clk IMX8M= P_SYS_PLL2_1000M>, > >>> <&clk IMX8MP_= CLK_24M>; > >>> - assigned-clock-rates =3D <266000000>; > >>> + assigned-clock-rates =3D <500000000>; > >=20 > > I am traveling, so I don't have the technical documents in front of > > me, but I beleive this is an over-drive speed, and 400MHz would be the > > single clock, standard rate. I created an imx8mm-overdrive and > > imx8mn-overdrive dtsi file to let users who operate in overdrive mode > > to update their clocks in one place. > >=20 > > I also think this goes down if the user is running two cameras instead > > of one. I re-read the old thread, and it's coming back to me, but > > until I can get settled into my hotel in Germany, I won't have time to > > review. I think the original idea was to use the lowest, conservative > > value with the idea that people can tweak their clock settings if > > they're only running one and if they are running in over-drive mode. >=20 > MX8MPCEC does indeed read 400 MHz regular, 500 MHz overdrive. >=20 > Shall we align both CSI2 ports to 400 MHz ? Currently they are one 500=20 > MHz and the other 266 MHz . No, that won't do. The (industrial products) datasheet says (Table 1): * Single camera on CSI1: 400/500 MHz in normal/overdrive mode * Single camera on CSI2: 277 MHz * Dual camera on CSI1 & CSI2: 266 MHz Assuming you need CSI2 more likely in a dual camera setup only, defaulting = to 266MHz seems sensible to me. Best regards, Alexander =2D-=20 TQ-Systems GmbH | M=C3=BChlstra=C3=9Fe 2, Gut Delling | 82229 Seefeld, Germ= any Amtsgericht M=C3=BCnchen, HRB 105018 Gesch=C3=A4ftsf=C3=BChrer: Detlef Schneider, R=C3=BCdiger Stahl, Stefan Sch= neider http://www.tq-group.com/