From patchwork Tue Aug 30 19:32:33 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brian Norris X-Patchwork-Id: 12959783 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 687DDECAAA1 for ; Tue, 30 Aug 2022 19:34:13 +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=geZJWiKyNaoM4zzIyh2bh5ofJeuTz7HmeKTQDJCWuqI=; b=3hNnQ+dKvgswTm CDR2E26buR8eIqZBoCrBMQ3+eYKrcz1h+ZFiKVzuxQi+de/SnJKMlfx8AuuNjaR0e6i6F1TLLa8ZT /QQ1cv4Tm/5T44kd+PUMNt0Xa2U/OqJzMLGnvvR5278tv2CQS4A7wX8lUpM9YbLLROyaqN4cLAZWE bBizufQdFC+TIf4JjtrFmaKDWT+xRcUTonNaF1iccII0rjg8+Q9T+yJuDWTEgywq4conU7srCHWJG n2wscNAZpRbn3wFw3cUH3Drk9D+b9qLYuQqjUflTvA1JXvFAT/lrIWRV3708MqOz0hKp/yVnQo4lU 6igjJX4eTPaAuglYkyrQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oT6yl-001TAF-K8; Tue, 30 Aug 2022 19:32:55 +0000 Received: from mail-pj1-x102d.google.com ([2607:f8b0:4864:20::102d]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oT6yh-001T7c-O7 for linux-arm-kernel@lists.infradead.org; Tue, 30 Aug 2022 19:32:53 +0000 Received: by mail-pj1-x102d.google.com with SMTP id mj6so7038895pjb.1 for ; Tue, 30 Aug 2022 12:32:45 -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=OYzA9p0n5o59safiaW4KMlIlfnAxPamL+boi+em99/M=; b=W851mZSHA2NuVBwcGoGcf21aojaeZQ6itzde6gqVH7X2Aejqg6gmKniUdZpYCGwMgr /VYzjXwux5er4xhFoJ0SDpu1AxswH9or1LBBQDLKe2Ys/Yy9YyeyaOpZ8rS2ida5eoV6 X2Ic6/yFW7PMZ82ej3p8GBPLvZV4vcpIpyLIg= 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=OYzA9p0n5o59safiaW4KMlIlfnAxPamL+boi+em99/M=; b=rrQM+TnRKTYnGrIytRBQNGMzodU5M9fI0qNwOQOWwNftnod9KpB/LRIR8xRoujPJll i53bQJ0QyAv3w82vdkxbUGt1fRCpxbd4vB7mTZPE0S7Wrmb2N2Yx4ns9LtsBKAXFO1l3 YqBJPf9X1Bl4dgsZN8vmPHlk8bfCTAF+CklD9fV9KAbjPhHnxA+0dZcdqxSN/X6De1As HC9F9b5dLJEagylaO1BK0jxz/LnV8UeEuugxfLNmlD5xY9lD+A+1j9TdE9N43ZXk8go7 /F6KzD/noihgzdv9z6V6+46GW+0VSNUU9L5xnq6A4LBAqGVfRxTIfDAE1Jjorfubnqf4 cN9g== X-Gm-Message-State: ACgBeo2mEm88DovD13sYYRn5fX20kgDAvBOuCrhxRItRcPXRahrdpJYR CV3+X2V+BXiOtMKaR25OZyL97g== X-Google-Smtp-Source: AA6agR5a1ydzTy5CU1whWuOm/VAiahfPCvqjM4F31B9VPVSXp3Z7Evq1Nk8FjLUtWiUUav60coeBOQ== X-Received: by 2002:a17:902:d501:b0:174:c4c9:9b77 with SMTP id b1-20020a170902d50100b00174c4c99b77mr10894828plg.67.1661887965373; Tue, 30 Aug 2022 12:32:45 -0700 (PDT) Received: from localhost ([2620:15c:202:201:d14a:ebf8:88f1:35e]) by smtp.gmail.com with UTF8SMTPSA id z5-20020a17090a66c500b001f334aa9170sm8868376pjl.48.2022.08.30.12.32.43 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 30 Aug 2022 12:32:44 -0700 (PDT) From: Brian Norris To: Heiko Stuebner Cc: zain wang , Lin Huang , linux-rockchip@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Douglas Anderson , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Brian Norris Subject: [PATCH] arm64: dts: rockchip: Set RK3399-Gru PCLK_EDP to 24 MHz Date: Tue, 30 Aug 2022 12:32:33 -0700 Message-Id: <20220830123231.1.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_123251_840448_41A175EB X-CRM114-Status: GOOD ( 10.98 ) 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 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. Signed-off-by: zain wang Signed-off-by: Brian Norris Reviewed-by: Douglas Anderson --- 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>;