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 X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A9421C433F5 for ; Wed, 22 Sep 2021 15:16:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 81DB8610A1 for ; Wed, 22 Sep 2021 15:16:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236304AbhIVPRz convert rfc822-to-8bit (ORCPT ); Wed, 22 Sep 2021 11:17:55 -0400 Received: from relay4-d.mail.gandi.net ([217.70.183.196]:56421 "EHLO relay4-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233737AbhIVPRy (ORCPT ); Wed, 22 Sep 2021 11:17:54 -0400 Received: (Authenticated sender: gregory.clement@bootlin.com) by relay4-d.mail.gandi.net (Postfix) with ESMTPSA id B80F9E0006; Wed, 22 Sep 2021 15:16:22 +0000 (UTC) From: Gregory CLEMENT To: Pali =?utf-8?Q?Roh=C3=A1r?= , Michael Turquette , Stephen Boyd , Rob Herring , Greg Kroah-Hartman Cc: Andrew Lunn , Sebastian Hesselbarth , Vladimir Vid , Marek =?utf-8?Q?Beh=C3=BAn?= , linux-clk@vger.kernel.org, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [RESEND PATCH v5 5/6] arm64: dts: marvell: armada-37xx: add device node for UART clock and use it In-Reply-To: <20210922105433.11744-6-pali@kernel.org> References: <20210922105433.11744-1-pali@kernel.org> <20210922105433.11744-6-pali@kernel.org> Date: Wed, 22 Sep 2021 17:16:22 +0200 Message-ID: <87o88k63p5.fsf@BL-laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org Hello Pali, > This change defines DT node for UART clock "marvell,armada-3700-uart-clock" > and use this UART clock as a base clock for all UART devices. Sorry to not have pointed this earlier but I found something a little unusual, see below: > > Signed-off-by: Pali Rohár > --- > arch/arm64/boot/dts/marvell/armada-3720-db.dts | 4 ++++ > .../boot/dts/marvell/armada-3720-espressobin.dtsi | 4 ++++ > .../boot/dts/marvell/armada-3720-turris-mox.dts | 4 ++++ > arch/arm64/boot/dts/marvell/armada-3720-uDPU.dts | 4 ++++ > arch/arm64/boot/dts/marvell/armada-37xx.dtsi | 15 +++++++++++++-- > 5 files changed, 29 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/boot/dts/marvell/armada-3720-db.dts b/arch/arm64/boot/dts/marvell/armada-3720-db.dts > index 3e5789f37206..accf014a6a1e 100644 > --- a/arch/arm64/boot/dts/marvell/armada-3720-db.dts > +++ b/arch/arm64/boot/dts/marvell/armada-3720-db.dts > @@ -191,6 +191,10 @@ > }; > }; > > +&uartclk { > + status = "okay"; I found unusual to have to enable the clock at device tree level. Usually the clock driver is always loaded and then the clock is really enabled or disabled through the clock framework. [...] > diff --git a/arch/arm64/boot/dts/marvell/armada-37xx.dtsi b/arch/arm64/boot/dts/marvell/armada-37xx.dtsi > index 9acc5d2b5a00..5bc61c9615f5 100644 > --- a/arch/arm64/boot/dts/marvell/armada-37xx.dtsi > +++ b/arch/arm64/boot/dts/marvell/armada-37xx.dtsi > @@ -132,10 +132,21 @@ > reg = <0x11500 0x40>; > }; > > + uartclk: uartclk@12000 { > + compatible = "marvell,armada-3700-uart-clock"; > + reg = <0x12010 0x4>, <0x12210 0x4>; > + clocks = <&tbg 0>, <&tbg 1>, <&tbg 2>, > + <&tbg 3>, <&xtalclk>; > + clock-names = "TBG-A-P", "TBG-B-P", "TBG-A-S", > + "TBG-B-S", "xtal"; > + #clock-cells = <1>; I think you could remove the following line and thanks to this there won't be any change in the dts of the board: > + status = "disabled"; > + }; > + Gregory > uart0: serial@12000 { > compatible = "marvell,armada-3700-uart"; > reg = <0x12000 0x18>; > - clocks = <&xtalclk>; > + clocks = <&uartclk 0>; > interrupts = > , > , > @@ -147,7 +158,7 @@ > uart1: serial@12200 { > compatible = "marvell,armada-3700-uart-ext"; > reg = <0x12200 0x30>; > - clocks = <&xtalclk>; > + clocks = <&uartclk 1>; > interrupts = > , > ; > -- > 2.20.1 > -- Gregory Clement, Bootlin Embedded Linux and Kernel engineering http://bootlin.com