From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-m32105.qiye.163.com (mail-m32105.qiye.163.com [220.197.32.105]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 87805316910; Mon, 17 Nov 2025 07:12:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.32.105 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763363545; cv=none; b=Febhd/1fTXV7gB6rzMkJbn2xneEBbBGWyj5TiNwa/wFxlilasiipTXTSPhpRJv6mecmRIOVjEKetfUMVnKMkvDXcqy+hnqZUqj8ktx+50FHY9J7WVK/CpOjjWCsTaQEQMAj1IdPJIBdZw/c3jhb2nfDvfVzuYg0MrSJoOLC+OKg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763363545; c=relaxed/simple; bh=hBs7BWFuJLm3njcdhha6spSB4xF2eB1P648L2la8O7A=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=ABRQ7a1U/e/DXOW4qC5jRK25L+27OMqF5/S+x0xrdeTgZ/r2kQGvunt3lPghRqrNGWTH6sLf2ohOXUAA8H5cMgoh15NoH2fUmCMCciCRcKMahVcZmMbD+avshwaiemxOWxDshBErIG2vjH2gF7EX/WKzWDaAu66jR3wu7Cb4i5c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rock-chips.com; spf=pass smtp.mailfrom=rock-chips.com; dkim=pass (1024-bit key) header.d=rock-chips.com header.i=@rock-chips.com header.b=iqz49SGW; arc=none smtp.client-ip=220.197.32.105 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rock-chips.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rock-chips.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=rock-chips.com header.i=@rock-chips.com header.b="iqz49SGW" 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 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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; 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(-) >