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 00609CCF9F8 for ; Wed, 5 Nov 2025 09:08:19 +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:In-Reply-To:References:To:From:Subject: Cc:Message-Id:Date:Mime-Version:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=JvtpjxDscuCXHkpGWO0T2RzP+9MBzMb0v+yc5S+zZso=; b=uiZBPkOQ7zKw2y VhpYJhuEp8pE9Fm4N/uLTh2CFBKD0r9l3BvQ8cnEDr0+uVd0pGxarjJjBM7Y757U8jaRJNsLvhux/ PQja12r2EBdoSBgjskR2Ce6KVIPCYdG11U23TQ8aFYF7rgGkmAkYdpGPuHPhbia8PxASmsMMKGSnb 3jrGwZmaobpeRa6VawhEIY6suoSa2DVIVkTJfndEyhLvyUKORAOPlnfhCf32s0ihiNWs93H2uMCNO BfmEmR+qAxv5a10STKk7fdCjSMKugXfIWqOP9B2wKoG+45EB6O7A2sgvL7myn+K5sj+AFpTs9sjU3 BpAAY+m3N9p39hEdwMVw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vGZUy-0000000DLwq-3OJx; Wed, 05 Nov 2025 09:08:12 +0000 Received: from out-177.mta1.migadu.com ([95.215.58.177]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vGZUw-0000000DLsC-12GW for linux-rockchip@lists.infradead.org; Wed, 05 Nov 2025 09:08:12 +0000 Mime-Version: 1.0 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cknow-tech.com; s=key1; t=1762333619; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=20X0FggjNIZtK2wTcA0T98MzwYS7d/pU6xJcudRoIkA=; b=aQkDEf0o1hZDlA0jt/SAK7d1jIzuk83Wctvw7Khhjx221G75fVkjY6y1QChQga2p0H/gx7 jb80JscYaEXymno4WJMr7sszvCliTv/kGLD5aPpkUxXzuRqF+LkkqfxPFih1rr28zE2J5F Nj4j+BNbr3lDj3fzWXfFiSEnTYem1pnhUR9c9vbgezDW3NOmMRyx8jOQBlK+rwIJRQ5dn4 cPCszNjP4TFptEs6ceoB1Ye5Vpg52GLT54a2vP6c7ydi7ZQ3/JmqQEDGRhGO6hyULD+3U+ nFWJc2Q+h1lvn//Uu3Vn7Ypoy5RnrjIoRappU70Tf1Txx5KyWKhpEUk1DdPkTw== Date: Wed, 05 Nov 2025 10:06:53 +0100 Message-Id: Cc: , "Shawn Lin" , "Lorenzo Pieralisi" , =?utf-8?q?Krzysztof_Wilczy=C5=84ski?= , "Manivannan Sadhasivam" , "Rob Herring" , "Bjorn Helgaas" , "Heiko Stuebner" , , , , , "Krzysztof Kozlowski" , "Conor Dooley" , "Johan Jonker" Subject: Re: [RFC PATCH 2/2] PCI: rockchip-host: drop wait on PERST# toggle X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: "Diederik de Haas" To: "Geraldo Nascimento" , "Bjorn Helgaas" References: <20251103181038.GA1814635@bhelgaas> In-Reply-To: X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251105_010810_870759_2F6A0602 X-CRM114-Status: GOOD ( 18.80 ) X-BeenThere: linux-rockchip@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Upstream kernel work for Rockchip platforms List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+linux-rockchip=archiver.kernel.org@lists.infradead.org On Wed Nov 5, 2025 at 4:55 AM CET, Geraldo Nascimento wrote: > On Mon, Nov 03, 2025 at 12:10:38PM -0600, Bjorn Helgaas wrote: >> On Mon, Nov 03, 2025 at 03:27:25AM -0300, Geraldo Nascimento wrote: >> > With this change PCIe will complete link-training with a known quirky >> > device - Samsung OEM PM981a SSD. This is completely against the PCIe > > Something in my intuition kept telling me this was PERST# related, > and so I followed that rabbit-hole. > > It seems the following change will allow the SSD to work with the > Rockchip-IP PCIe core without any other changes. So it is purely > a DT change and we are able to keep the mandatory 100ms delay > after driving PERST# low, as well as the always-on/boot-on > properties of the 3v3 power regulator. > > This time everything is within the PCIe spec AFAICT, PERST# indeed > is an Open Drain signal, and indeed it does requires pull-up resistor > to maintain the drive after driving it high. > > I'm still testing the overall stability of this, let's hope for the > best! I have a Samsung PM981 (without the 'a') and AFAICT it works fine. I had noticed that the PERST# (pinctrl) was missing, but 'ep-gpios' was/is new to me and I hadn't had time to research that properly yet. Good to see you already found it yourself :-) Cheers, Diederik > diff --git a/arch/arm64/boot/dts/rockchip/rk3399pro-vmarc-som.dtsi b/arch/arm64/boot/dts/rockchip/rk3399pro-vmarc-som.dtsi > index aa70776e898a..1c5afc0413bc 100644 > --- a/arch/arm64/boot/dts/rockchip/rk3399pro-vmarc-som.dtsi > +++ b/arch/arm64/boot/dts/rockchip/rk3399pro-vmarc-som.dtsi > @@ -383,13 +383,14 @@ &pcie_phy { > }; > > &pcie0 { > - ep-gpios = <&gpio0 RK_PB4 GPIO_ACTIVE_HIGH>; > + ep-gpios = <&gpio0 RK_PB4 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>; > num-lanes = <4>; > - pinctrl-0 = <&pcie_clkreqnb_cpm>; > + pinctrl-0 = <&pcie_clkreqnb_cpm>, <&pcie_perst>; > pinctrl-names = "default"; > vpcie0v9-supply = <&vcca_0v9>; /* VCC_0V9_S0 */ > vpcie1v8-supply = <&vcca_1v8>; /* VCC_1V8_S0 */ > vpcie3v3-supply = <&vcc3v3_pcie>; > + max-link-speed = <2>; > status = "okay"; > }; > > @@ -408,6 +409,10 @@ pcie { > pcie_pwr: pcie-pwr { > rockchip,pins = <4 RK_PD4 RK_FUNC_GPIO &pcfg_pull_up>; > }; > + pcie_perst: pcie-perst { > + rockchip,pins = <0 RK_PB4 RK_FUNC_GPIO &pcfg_pull_up>; > + }; > + > }; > > pmic { > _______________________________________________ Linux-rockchip mailing list Linux-rockchip@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-rockchip