From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id F1CB1C433F5 for ; Thu, 16 Dec 2021 05:59:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=WEzl5LPToadG3Qv6Rio3z5ub7P87VX+1AEYl2mx9+Po=; b=tTfwtyUg3igcAD oJ6z00WnRVT6qcSoZ3ST/o4WxQlsGV9Lb3/Fn6M5ztrhEsvPXrOH0vyhONjp6/r+IRFDhCTVjOxku Cjwkypzd4K9+WqFr0TnXImOvoYkUqYWPzJpdxI6+9Ca42hnUW3vw6HDYsxQAFOP0QPaeHeVM7pS1S NW922u0G/deVHREABE1XZ1QvNRqvu4mtBuPNRki94a1WlASoat1KibuWowIlVlu7+L8TlFiiFON9b ksm6TcVH3UqhFK0cFsw3YygzenU7PaChZncXXSGWSvQknvuMQ7MNTkXYxwxh00w5X3NUf35JAtRQD HBncjuMAhciAvie2rVig==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mxjmM-003g9G-PR; Thu, 16 Dec 2021 05:58:10 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mxjmJ-003g8J-Jy for linux-arm-kernel@lists.infradead.org; Thu, 16 Dec 2021 05:58:08 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 262BF61BF7; Thu, 16 Dec 2021 05:58:07 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4B15CC36AE0; Thu, 16 Dec 2021 05:58:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1639634286; bh=tdQS8NS0p05njV6mVMg3rxQ7Upin7VpcviZuF24R8W4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=q0bNbO3wc/HRGgEKgxf4Re3MlLuCx9D/UIgCV/P3ZERaBydP924J5H7pFCZmnxgA+ zJP9Bekz9rKNzTTKErCd3OHAzcTCkXi1x2WaaFiQjXVNAjmXdr5V6I4W/XDseFILs8 8xvRlApXjdefglvVzUTy8OWFV2wKhphm7G48+EmOQ7M5iFFnmzXgZo+XG/OAmAkRBl bH82mecOg0jyGiZusoZViTOUuf2+Qmpa0K2aItyTeIEnYPQa/LDgWNfn3qBl/214w0 9lutRrqgUBl4aHm475heSagFNZ7X1O3mbIFJ89t7w2Z55FwMzFgri7eOoSEGzGY54+ UnV/C0yMmbaDQ== Date: Thu, 16 Dec 2021 13:58:00 +0800 From: Shawn Guo To: Lucas Stach Cc: Pengutronix Kernel Team , Fabio Estevam , NXP Linux Team , Guido =?iso-8859-1?Q?G=FCnther?= , Martin Kepplinger , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] arm64: dts: imx8mq: disable DDRC node by default Message-ID: <20211216055800.GV4216@dragon> References: <20211212191541.2148178-1-dev@lynxeye.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20211212191541.2148178-1-dev@lynxeye.de> User-Agent: Mutt/1.9.4 (2018-02-28) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211215_215807_724628_C1C395B0 X-CRM114-Status: GOOD ( 21.36 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sun, Dec 12, 2021 at 08:15:41PM +0100, Lucas Stach wrote: > Without a OPP table or a downstream TF-A running on the system the DDRC will > fail to probe, as it has no means to scale the DRAM frequency in that case. > This however will block the bus scaling driver to come up and this in turn > prevents other devices that hook into the interconnect from probing. > > If the DDRC is disabled, the interconnect driver will simply ignore it. As > most systems don't want to scale the DRAM frequency, disable the node by > default and only enable it on the systems that actually uses this > capability and provides a valid OPP table in the DT. > > Signed-off-by: Lucas Stach > --- > arch/arm64/boot/dts/freescale/imx8mq-evk.dts | 1 + > arch/arm64/boot/dts/freescale/imx8mq-librem5.dtsi | 1 + > arch/arm64/boot/dts/freescale/imx8mq.dtsi | 1 + > 3 files changed, 3 insertions(+) > > diff --git a/arch/arm64/boot/dts/freescale/imx8mq-evk.dts b/arch/arm64/boot/dts/freescale/imx8mq-evk.dts > index b83df77195ec..e989a9e450ed 100644 > --- a/arch/arm64/boot/dts/freescale/imx8mq-evk.dts > +++ b/arch/arm64/boot/dts/freescale/imx8mq-evk.dts > @@ -122,6 +122,7 @@ &A53_3 { > }; > > &ddrc { > + status = "okay"; Please move it to end of property list. Shawn > operating-points-v2 = <&ddrc_opp_table>; > > ddrc_opp_table: opp-table { > diff --git a/arch/arm64/boot/dts/freescale/imx8mq-librem5.dtsi b/arch/arm64/boot/dts/freescale/imx8mq-librem5.dtsi > index 60d47c71499b..5c0e98c36f94 100644 > --- a/arch/arm64/boot/dts/freescale/imx8mq-librem5.dtsi > +++ b/arch/arm64/boot/dts/freescale/imx8mq-librem5.dtsi > @@ -238,6 +238,7 @@ &A53_3 { > }; > > &ddrc { > + status = "okay"; > operating-points-v2 = <&ddrc_opp_table>; > > ddrc_opp_table: opp-table { > diff --git a/arch/arm64/boot/dts/freescale/imx8mq.dtsi b/arch/arm64/boot/dts/freescale/imx8mq.dtsi > index 972766b67a15..f5af9765e239 100644 > --- a/arch/arm64/boot/dts/freescale/imx8mq.dtsi > +++ b/arch/arm64/boot/dts/freescale/imx8mq.dtsi > @@ -1554,6 +1554,7 @@ ddrc: memory-controller@3d400000 { > <&clk IMX8MQ_DRAM_PLL_OUT>, > <&clk IMX8MQ_CLK_DRAM_ALT>, > <&clk IMX8MQ_CLK_DRAM_APB>; > + status = "disabled"; > }; > > ddr-pmu@3d800000 { > -- > 2.31.1 > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel