From patchwork Thu Feb 22 14:52:03 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Perrot X-Patchwork-Id: 1902817 X-Patchwork-Delegate: uboot@andestech.com Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=bootlin.com header.i=@bootlin.com header.a=rsa-sha256 header.s=gm1 header.b=N7LcHMg3; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.denx.de (client-ip=85.214.62.61; helo=phobos.denx.de; envelope-from=u-boot-bounces@lists.denx.de; receiver=patchwork.ozlabs.org) Received: from phobos.denx.de (phobos.denx.de [85.214.62.61]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (secp384r1) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4TgbjX1h67z23d2 for ; Fri, 23 Feb 2024 01:53:04 +1100 (AEDT) Received: from h2850616.stratoserver.net (localhost [IPv6:::1]) by phobos.denx.de (Postfix) with ESMTP id CCE528808C; Thu, 22 Feb 2024 15:52:58 +0100 (CET) Authentication-Results: phobos.denx.de; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=u-boot-bounces@lists.denx.de Authentication-Results: phobos.denx.de; dkim=pass (2048-bit key; unprotected) header.d=bootlin.com header.i=@bootlin.com header.b="N7LcHMg3"; dkim-atps=neutral Received: by phobos.denx.de (Postfix, from userid 109) id B91C28809C; Thu, 22 Feb 2024 15:52:56 +0100 (CET) X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on phobos.denx.de X-Spam-Level: X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_PASS,SPF_PASS, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.2 Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [IPv6:2001:4b98:dc4:8::227]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by phobos.denx.de (Postfix) with ESMTPS id 7ED1288087 for ; Thu, 22 Feb 2024 15:52:54 +0100 (CET) Authentication-Results: phobos.denx.de; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=thomas.perrot@bootlin.com Received: by mail.gandi.net (Postfix) with ESMTPSA id EB4AD20003; Thu, 22 Feb 2024 14:52:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1708613574; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=jAt8Mf946L/bg6WNqFU1z+YcUR+wMUk/itxtXignECg=; b=N7LcHMg3Zo6iFjValZVBiMz/KK0aakxsB0E1P1UO43NZtF087nDtpebn/hauUlI/gcr99G 2kR47mf66iGD4AKhwyOswipH4QLLoY4EECSaIbBaFukHGqciiIQXFNBaj4haiUoLSF6VXT JQajD+pvroXm970yMpAY+5nEAjyjOzOZqf+ygFCy1v4fb9O+rki3Ulj5EtL57ybwtPbKrM joHWxaRVE76bq7exdUnl/d5r2XF8l+1RBRsbx9YSsKR2p3oPRKXcA47ZTPII3ScZxWnRHf t1uBF+GESs6DZ/khP7c/STFZ7yznvQVTSB1pSvTzCiiUy42d0QG709JxQWQaug== From: thomas.perrot@bootlin.com To: u-boot@lists.denx.de Cc: Thomas Perrot Subject: [PATCH] riscv: sifive: fu740: reduce DDR speed from 1866MT/s to 1600MT/s Date: Thu, 22 Feb 2024 15:52:03 +0100 Message-ID: <20240222145203.2659671-1-thomas.perrot@bootlin.com> X-Mailer: git-send-email 2.43.2 MIME-Version: 1.0 X-GND-Sasl: thomas.perrot@bootlin.com X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.39 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: u-boot-bounces@lists.denx.de Sender: "U-Boot" X-Virus-Scanned: clamav-milter 0.103.8 at phobos.denx.de X-Virus-Status: Clean From: Thomas Perrot It appears that there is some timing marginality either in the board layout or the SoC that results in occasional data corruption on some boards. We observed this issue on some of the new HiFive Unmatched RevB boards during volume production as well as some of the original HiFive Unmatched boards from 2021 in our possession. This means that there are other boards out there that might have the issue too. We have done some limited testing with DDR4 at 1600MT/s and faulty boards (failing at 1866MT/s) passed. We plan further testing after we procure a temperature chamber. Signed-off-by: Thomas Perrot Reviewed-by: Leo Yu-Chi Liang --- arch/riscv/dts/fu740-c000-u-boot.dtsi | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/riscv/dts/fu740-c000-u-boot.dtsi b/arch/riscv/dts/fu740-c000-u-boot.dtsi index 706224b384d2..956237c3218e 100644 --- a/arch/riscv/dts/fu740-c000-u-boot.dtsi +++ b/arch/riscv/dts/fu740-c000-u-boot.dtsi @@ -77,7 +77,7 @@ 0x0 0x100b2000 0x0 0x2000 0x0 0x100b8000 0x0 0x1000>; clocks = <&prci FU740_PRCI_CLK_DDRPLL>; - clock-frequency = <933333324>; + clock-frequency = <800000004>; bootph-pre-ram; }; };