From patchwork Tue Aug 30 20:16:17 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brian Norris X-Patchwork-Id: 12959849 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 A453AECAAA1 for ; Tue, 30 Aug 2022 20:19:05 +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:MIME-Version:Message-Id:Date:Subject:Cc :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=DkI8ahY7C0mZvoQ6m6c8zAO8uHStrzjiSHfxhhDqGcE=; b=iFTXNWIgDuTOWs u3i7ykPxwwzFiUqTKVbkAXLlu9NrFHi4ev4372cz4Y/1IGaKWq4FKASNQIlkGRXMrw7ivy/YEw3Ni 4rzHVGN9zVwr9HyVZPtwL/9v8Rxh+4dgNqkbE6Tb45ROKSJrEk8PHmWsYf0hufqebZM7yXdWsePVt uMxQ6Zbg4js8v0kmo6h6fcfX6I3P6LN52+tLO+eeQb8HlhG/8ImC52E3nVPXuJnLZ+2own3FKriBF dXYENLyUUkVuJu5K1+F2lcOLQWqrN0VqW98EGFwNZnYr+5frzz7UCumZHVQGl3UeA4RfdGlFyl91u /i3uOui4C4zGAo085c2A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oT7gO-001oJZ-LF; Tue, 30 Aug 2022 20:18:00 +0000 Received: from mail-pj1-x102e.google.com ([2607:f8b0:4864:20::102e]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oT7gL-001oHj-By for linux-arm-kernel@lists.infradead.org; Tue, 30 Aug 2022 20:17:58 +0000 Received: by mail-pj1-x102e.google.com with SMTP id t11-20020a17090a510b00b001fac77e9d1fso19056270pjh.5 for ; Tue, 30 Aug 2022 13:17:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc; bh=8Amg5b56oQl+ZjuCqznlrXnzwH450EVUCei1qHh8YaA=; b=cLHGfYpFjKg4LfQbdwq1ncMirzhvpWWcCdSP0WPnrYpwI08hPAR57Vp2rkQqSa9qF3 hbHyzoQCOctpv6ij5bBZOau+F77S2b1Nkp4Chiv+Y7dCdL+SG+iogvYy+JZfeDxyjxHp tn60S3B9Ag2xe1RJovoMsTfrD1cotR/e7tnkE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc; bh=8Amg5b56oQl+ZjuCqznlrXnzwH450EVUCei1qHh8YaA=; b=CetSYRjHagpA0tk44hCgY/WaVS4lt4vIsxYF6sOcALMbXLwcNnUYHW8riBihAEOFQ0 jE1+Sow3PPHorHwMVRZUMUo/9iv0Kx8KE9+d1hBjuiuWUEqaN+Wdz6Ob7mKd56I7pFsi Jb7hppOvSfBIkcfvBNYdfp9OlgqfQ8CLxHw0VxKvO3KV/aamRTNsDYBUbSyDLxTPmD1d YRYcVD96gzGitYhmQUQip8vy0wY6l8W5nVF34b1H9DC0+stZJd3U+ug3t9X7mg+r13Kd B1qccb4edLjoD3a6Zc9QJ3QCsTEOTEQB2EZkGSOjAsgGKy2LgW94ueGA25MEEuQMcDEk kxgQ== X-Gm-Message-State: ACgBeo0GvbkBlf2MXA0vqtTzaGx5HRgJp9X5LpiFYPnyxs0DnskEzaSd Q1NM36oDYHGAYeSgogOvcxjMVA== X-Google-Smtp-Source: AA6agR71P/HmC5vMFbdfvfVHoIYJy/fkqJ/ObJltZwgbWIk8mUDynhEUCoJF82BTs1NDNqkjbf5weQ== X-Received: by 2002:a17:90b:1e4a:b0:1f5:4f69:d6b4 with SMTP id pi10-20020a17090b1e4a00b001f54f69d6b4mr25598894pjb.164.1661890675446; Tue, 30 Aug 2022 13:17:55 -0700 (PDT) Received: from localhost ([2620:15c:202:201:d14a:ebf8:88f1:35e]) by smtp.gmail.com with UTF8SMTPSA id x196-20020a6286cd000000b00536816c0d4asm10036104pfd.147.2022.08.30.13.17.54 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 30 Aug 2022 13:17:55 -0700 (PDT) From: Brian Norris To: Heiko Stuebner Cc: linux-rockchip@lists.infradead.org, linux-arm-kernel@lists.infradead.org, zain wang , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, Douglas Anderson , Lin Huang , Brian Norris Subject: [PATCH v2] arm64: dts: rockchip: Set RK3399-Gru PCLK_EDP to 24 MHz Date: Tue, 30 Aug 2022 13:16:17 -0700 Message-Id: <20220830131212.v2.1.I98d30623f13b785ca77094d0c0fd4339550553b6@changeid> X-Mailer: git-send-email 2.37.2.672.g94769d06f0-goog MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220830_131757_454769_03DCDCB1 X-CRM114-Status: GOOD ( 11.23 ) 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 From: zain wang We've found the AUX channel to be less reliable with PCLK_EDP at a higher rate (typically 25 MHz). This is especially important on systems with PSR-enabled panels (like Gru-Kevin), since we make heavy, constant use of AUX. According to Rockchip, using any rate other than 24 MHz can cause "problems between syncing the PHY an PCLK", which leads to all sorts of unreliabilities around register operations. Reviewed-by: Douglas Anderson Signed-off-by: zain wang Signed-off-by: Brian Norris --- Changes in v2: * Add Doug's reviewed-by * Set authorship correctly arch/arm64/boot/dts/rockchip/rk3399-gru-chromebook.dtsi | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/arm64/boot/dts/rockchip/rk3399-gru-chromebook.dtsi b/arch/arm64/boot/dts/rockchip/rk3399-gru-chromebook.dtsi index 45796b9fd94f..ee6095baba4d 100644 --- a/arch/arm64/boot/dts/rockchip/rk3399-gru-chromebook.dtsi +++ b/arch/arm64/boot/dts/rockchip/rk3399-gru-chromebook.dtsi @@ -244,6 +244,14 @@ &dmc { &edp { status = "okay"; + /* + * eDP PHY/clk don't sync reliably at anything other than 24 MHz. Only + * set this here, because rk3399-gru.dtsi ensures we can generate this + * off GPLL=600MHz, whereas some other RK3399 boards may not. + */ + assigned-clocks = <&cru PCLK_EDP>; + assigned-clock-rates = <24000000>; + ports { edp_out: port@1 { reg = <1>;