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 2C26AC5B572 for ; Wed, 19 Aug 2026 07:26:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=GyP+BjT/b2lYpBkJypWs28s3CD47CYLAv7ie7DV3fF4=; b=ClvWb7Tjk+U7zG/IpzpUlbhMVn JaW/CSR0BsaZ2xRBgn+Sbev/MPBgXEnCfxRl8QbX6QGVJLTLNypciI1+GP4pq6ZviI54Kv6mjBmHW mlr/k7uu5G5llCfOk1KD48U7WBqvjZgU7svXEPXo/zbtC3bpCH+ZwGuq0xPdocKa/8wVBHwS7EGo4 zsbRgWQvQjbJAXYiABTMhkNxjZ1pjsi47ecuwKHdYAo0+cUaHjDwyiIha1taVZIy/3xFmqicL+tv3 2h9VhRHhfyKqmhdNyYSpmEQDTD4UklHENspdzocDHTDM7RuSaeQFhsUw5spJ4WxC6Y5mkBTfVBbqH lcrg82xw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wwagi-00000009Bow-3XzN; Wed, 19 Aug 2026 07:26:16 +0000 Received: from courrier.aliel.fr ([65.21.61.41]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wwage-00000009BoC-2wcp; Wed, 19 Aug 2026 07:26:15 +0000 Message-ID: <6673edea-6822-4368-9374-29f92195fcf5@aliel.fr> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=aliel.fr; s=courrier-s1; t=1787124356; bh=zfApjPryrOyf0fxxl1ecWqnrsetooI24vtnZRIvXq7c=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=seQBr+cK9g2XeyPGBo5qh2mBtmRJs+lE8qfi/e2B/RSSo+/WTX9KteAhoKY9Epncg shEH21hDzyL8WVCIwtD7VsyjdtBxXjfWF6a/0GMnl9q9QDZWnl6PCt9Ei3epb1PzS7 U964U4PvEjM32a0oj8liqP3kZ83nT7b1KnTXSYTo= Date: Wed, 19 Aug 2026 09:25:54 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Beta Subject: Re: [PATCH 1/2] arm64: dts: amlogic: t7: use the real UART pclk To: Xianwei Zhao , Lucas Tanure Cc: linux-arm-kernel@lists.infradead.org, linux-amlogic@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Neil Armstrong , Kevin Hilman , Rob Herring , Krzysztof Kozlowski , Conor Dooley References: <20260818191159.11523-1-tanure@linux.com> <20260818191159.11523-2-tanure@linux.com> Content-Language: en-US From: Ronald Claveau In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260819_002613_205942_4CFA45F5 X-CRM114-Status: GOOD ( 16.20 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 8/19/26 4:39 AM, Xianwei Zhao wrote: > Hi Lucas, > > On 2026/8/19 03:11, Lucas Tanure wrote: >> uart_a lists the 24MHz crystal for all three of its clocks, because >> the T7 clock controller driver did not exist when these boards were >> added. >> >> That leaves the real UART bus clock without a user, so the kernel >> turns it off when it disables unused clocks at the end of boot, and >> the board hangs. >> >> Point uart_a at the real clocks, the way meson-s4.dtsi does, and drop >> the placeholders from the two board files. >> >> Fixes: 4fef056588f5 ("arm64: dts: amlogic-t7-a311d2-khadas-vim4: add >> initial device-tree") >> Fixes: 6f048cc7a635 ("arm64: dts: add board AN400") >> Signed-off-by: Lucas Tanure >> Assisted-by: Claude:claude-fable-5 >> --- >>   arch/arm64/boot/dts/amlogic/amlogic-t7-a311d2-an400.dts       | 2 -- >>   arch/arm64/boot/dts/amlogic/amlogic-t7-a311d2-khadas-vim4.dts | 2 -- >>   arch/arm64/boot/dts/amlogic/amlogic-t7.dtsi                   | 4 ++++ >>   3 files changed, 4 insertions(+), 4 deletions(-) >> >> diff --git a/arch/arm64/boot/dts/amlogic/amlogic-t7-a311d2-an400.dts >> b/arch/arm64/boot/dts/amlogic/amlogic-t7-a311d2-an400.dts >> index cab2ee9ea0d3..dcbcd08a78b9 100644 >> --- a/arch/arm64/boot/dts/amlogic/amlogic-t7-a311d2-an400.dts >> +++ b/arch/arm64/boot/dts/amlogic/amlogic-t7-a311d2-an400.dts >> @@ -33,7 +33,5 @@ xtal: xtal-clk { >>   }; >> >>   &uart_a { >> -       clocks = <&xtal>, <&xtal>, >> <&xtal>; >> -       clock-names = "xtal", "pclk", "baud"; >>          status = "okay"; >>   }; >> diff --git >> a/arch/arm64/boot/dts/amlogic/amlogic-t7-a311d2-khadas-vim4.dts >> b/arch/arm64/boot/dts/amlogic/amlogic-t7-a311d2-khadas-vim4.dts >> index c41525a34b72..677069e58f30 100644 >> --- a/arch/arm64/boot/dts/amlogic/amlogic-t7-a311d2-khadas-vim4.dts >> +++ b/arch/arm64/boot/dts/amlogic/amlogic-t7-a311d2-khadas-vim4.dts >> @@ -266,6 +266,4 @@ &sd_emmc_c { >> >>   &uart_a { >>          status = "okay"; >> -       clocks = <&xtal>, <&xtal>, >> <&xtal>; >> -       clock-names = "xtal", "pclk", "baud"; >>   }; >> diff --git a/arch/arm64/boot/dts/amlogic/amlogic-t7.dtsi >> b/arch/arm64/boot/dts/amlogic/amlogic-t7.dtsi >> index cc371fcd1896..7847582e77ed 100644 >> --- a/arch/arm64/boot/dts/amlogic/amlogic-t7.dtsi >> +++ b/arch/arm64/boot/dts/amlogic/amlogic-t7.dtsi >> @@ -587,6 +587,10 @@ uart_a: serial@78000 { >>                                  compatible = "amlogic,t7-uart", >> "amlogic,meson-s4-uart"; >>                                  reg = <0x0 0x78000 0x0 0x18>; >>                                  interrupts = > IRQ_TYPE_EDGE_RISING>; >> +                               clocks = <&xtal>, >> +                                        <&clkc_periphs >> CLKID_SYS_UART_A>, >> +                                        <&xtal>; >> +                               clock-names = "xtal", "pclk", "baud"; >>                                  status = "disabled"; >>                          }; > > I agree with moving the UART clock configuration to the DTSI file. > However, it seems a little odd to keep the XTAL clock definition in the > DTS, as the alias may not be consistent across different boards, which > could result in compilation errors. Could we move the XTAL clock > definition to the DTSI as well, similar to other Amlogic SoCs? It seems similar to changes in this series : https://lore.kernel.org/all/20260420-add-bluetooth-t7-vim4-v4-0-9505df0e7016@aliel.fr/ What do you think ? -- Best regards, Ronald