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 EC430D31A29 for ; Wed, 14 Jan 2026 09:36:56 +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:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=cwVF7NUGxMafHJQgSEyiKMbPe3kq4i/HiDJlqkNzzSA=; b=c9wIZISXDE1IgW ad9DUiD6FsiYdQrlEWVz7KOb0kRwpgHD1iOMrJtLxauDUCT0Rg++Pjxwn4k/UPSIF3E4vA/jE0IIZ NdoffwjcHSA2ANlLY+Pg+SXfB4s7261MEyRvDpKTgr63EdMiPWi0Xw/ZYJxNctD07b4En2rmHZQOk Grf2PKxwIqKz2k1RwRlGS+InH/ec5fOGUMJyu96WuQ/s6im0W+Ij1EHXLHiBKvukHPgV1TOimTOzA RcCY+Z+1vU92krtE5nbirveBH3w2+V17shEZyQ/oocw5JDyM/YcMc1693UqS7eJ9wiS2aaa1JpEuF 1/+oGd9RAOwmmiCehAww==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vfxJA-00000008awL-1xxr; Wed, 14 Jan 2026 09:36:56 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vfxJ8-00000008aw0-3q46 for linux-phy@lists.infradead.org; Wed, 14 Jan 2026 09:36:54 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 5B6CF6001D; Wed, 14 Jan 2026 09:36:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 58DFBC4CEF7; Wed, 14 Jan 2026 09:36:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1768383414; bh=Vd4jldM+sSvbw3Qs+faOiMfuX6C/rjZRaR+/l4tHfHU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=HqVOfbC46Uz/3VEhEysg9Z6Qh0ocLgMei+0QndPuf8J/aQ9JqBmm9xT/ObY/0gZ+J rpF7MptLiTMCDmZPQFbSr5OKMStMdawjfhkvvmNRiAVu6JDC91t8ZdmzF6oyj1xZu8 ePty8JFMbbXjazbIT07+odyE589qUa6oUyebKw6pM+hayhXEpOLMyR6OCrLm6tjTGz i39lkXMN0HW1hfWh8a12fbgf8/uKF9xv6FaT9PJJywNk3fTaQiTAUJkXd/6WDEc5Gq 7Wm5XwOjqcZjalGUZbWO/oLf527NMvtypUQ9sc05+fBwUie3VJ2Q1j7Ll9n3pIccLh eHBr6YS47PnbQ== Date: Wed, 14 Jan 2026 15:06:50 +0530 From: Vinod Koul To: Dmitry Baryshkov Cc: Neil Armstrong , Krishna Chaitanya Chundru , Philipp Zabel , Jingoo Han , Manivannan Sadhasivam , Lorenzo Pieralisi , Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= , Rob Herring , Bjorn Helgaas , linux-arm-msm@vger.kernel.org, linux-phy@lists.infradead.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org Subject: Re: [PATCH 1/5] phy: qcom: qmp-pcie: Skip PHY reset if already up Message-ID: References: <20260109-link_retain-v1-0-7e6782230f4b@oss.qualcomm.com> <20260109-link_retain-v1-1-7e6782230f4b@oss.qualcomm.com> <53f0c45f-7f5c-4abd-af84-cbb82d509872@linaro.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-BeenThere: linux-phy@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux Phy Mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-phy" Errors-To: linux-phy-bounces+linux-phy=archiver.kernel.org@lists.infradead.org On 09-01-26, 16:03, Dmitry Baryshkov wrote: > On Fri, Jan 09, 2026 at 02:10:49PM +0100, Neil Armstrong wrote: > > On 1/9/26 14:08, Dmitry Baryshkov wrote: > > > On Fri, Jan 09, 2026 at 12:51:06PM +0530, Krishna Chaitanya Chundru wrote: > > > > If the bootloader has already powered up the PCIe PHY, doing a full > > > > reset and waiting for it to come up again slows down boot time. > > > > > > How big is the delay caused by it? > > > > > > > > > > > Add a check for PHY status and skip the reset steps when the PHY is > > > > already active. In this case, only enable the required resources during > > > > power-on. This works alongside the existing logic that skips the init > > > > sequence. > > > > > > Can we end up in a state where the bootloader has mis-setup the link? Or > > > the link going bad because of any glitch during the bootup? > > > > Good question, can we add a module parameter to force a full reset of the PHY in case > > the bootloader is buggy ? > > I'd suggest a simpler thing: if the reset was skipped, reset the PHY in > case of an error and retry. That's also one of the reasons why I asked > for skip_reset not to be the persistent value. That is a better suggestion. Helps skips if it is configured and way to recover if buggy -- ~Vinod -- linux-phy mailing list linux-phy@lists.infradead.org https://lists.infradead.org/mailman/listinfo/linux-phy