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 9673CCE8D6B for ; Mon, 17 Nov 2025 03:43:20 +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:To:Subject:Cc: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=L/mOHkyVCGlpZGPK0VdOwC9RDdilpu9JCgLw5m5Dy4Y=; b=0phaeQlebjiIh3cjaSZRO94KbS HEm2AJxJwpF/A6XhkGkS9oPz5zUiHLVWLLIW9+CFV7M3GHgPBjYq+K8WZgwgQBKJDnPgG4hrpuNgi +53uV1dJZKMbK88vHBSNs8+gG2s21hzQLpOw0Ot7tUyVA9A4FGDztQODmmxhvEugnE0+5E+dfSPuL EiW4HIGQi+WKXpc3KdKGoRbSKajsSdh4vyEpmS001RkZ2H67U2SBOh95LW+hQIfVqmd9MhvhkLwN/ Z2TsaJeLbybE1YM4ci17hO9mQhoYSmmEY1gh48S+mjAYJiP6X7kwDMTrgFzrspjsfywTBC8IAV5IG 2/fV0s2w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vKq94-0000000FO8W-2bkZ; Mon, 17 Nov 2025 03:43:14 +0000 Received: from mail-m3269.qiye.163.com ([220.197.32.69]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vKq91-0000000FO7F-2HOp; Mon, 17 Nov 2025 03:43:13 +0000 Received: from [172.16.12.14] (unknown [58.22.7.114]) by smtp.qiye.163.com (Hmail) with ESMTP id 29c9004d4; Mon, 17 Nov 2025 11:42:59 +0800 (GMT+08:00) Message-ID: <8f3cc1c1-7bf7-4610-b7ce-79ebd6f05a6e@rock-chips.com> Date: Mon, 17 Nov 2025 11:42:59 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: shawn.lin@rock-chips.com, Lorenzo Pieralisi , =?UTF-8?Q?Krzysztof_Wilczy=C5=84ski?= , Manivannan Sadhasivam , Rob Herring , Bjorn Helgaas , Heiko Stuebner , linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, Krzysztof Kozlowski , Conor Dooley , Johan Jonker , Dragan Simic , linux-rockchip@lists.infradead.org Subject: Re: [PATCH 0/3] PCI: rockchip: 5.0 GT/s speed may be dangerous To: Geraldo Nascimento References: From: Shawn Lin In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-HM-Tid: 0a9a8fe8a40409cckunm2225600d70b383 X-HM-MType: 1 X-HM-Spam-Status: e1kfGhgUHx5ZQUpXWQgPGg8OCBgUHx5ZQUlOS1dZFg8aDwILHllBWSg2Ly tZV1koWUFDSUNOT01LS0k3V1ktWUFJV1kPCRoVCBIfWUFZGk9ISFZDHx8aThpIQxkdTU1WFRQJFh oXVRMBExYaEhckFA4PWVdZGBILWUFZTkNVSUlVTFVKSk9ZV1kWGg8SFR0UWUFZT0tIVUpLSU9PT0 hVSktLVUpCS0tZBg++ DKIM-Signature: a=rsa-sha256; b=iqz49SGWasZFgXzvmpgvrAR/MiWOraupVXaPEaboWVYCcb/RkncHqs1bDxk236bb5xLnrZpa/O9g9zIVR3QitzVvwYdmqnu25XhHXnG5UGEq/cJdWiS4vzlPE29CJQ8C9imQcmwuPVBFSZsuTZaZ61zjdE1XET97PRp2eNCjBec=; c=relaxed/relaxed; s=default; d=rock-chips.com; v=1; bh=L/mOHkyVCGlpZGPK0VdOwC9RDdilpu9JCgLw5m5Dy4Y=; h=date:mime-version:subject:message-id:from; X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251116_194312_071591_CAFB7BC8 X-CRM114-Status: GOOD ( 12.22 ) 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 Hi Geraldo, 在 2025/11/15 星期六 17:10, Geraldo Nascimento 写道: > In recent interactions with Shawn Lin from Rockchip it came to my > attention there's an unknown errata regarding 5.0 GT/s operational > speed of their PCIe core. According to Shawn there's grave danger > even if the odds are low. To contain any damage, let's cover the > remaining corner-cases where the default would lead to 5.0 GT/s > operation as well as add a comment to Root Complex driver core, > documenting this danger. > I'm not sure just adding a warn would be a good choice. Could we totally force to use gen1 and add a warn if trying to use Gen2. Meanwhile amend the commit message to add a reference of RK3399 official datesheet[1] which says PCIe on RK3399 should only support 2.5GT/s? [1]https://opensource.rock-chips.com/images/d/d7/Rockchip_RK3399_Datasheet_V2.1-20200323.pdf > Geraldo Nascimento (3): > PCI: rockchip: warn of danger of 5.0 GT/s speeds > PCI: rockchip-host: comment danger of 5.0 GT/s speed > arm64: dts: rockchip: drop max-link-speed = <2> in helios64 PCIe > > arch/arm64/boot/dts/rockchip/rk3399-kobol-helios64.dts | 1 - > drivers/pci/controller/pcie-rockchip-host.c | 5 +++++ > drivers/pci/controller/pcie-rockchip.c | 8 ++++++-- > 3 files changed, 11 insertions(+), 3 deletions(-) >