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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 72274C433FE for ; Mon, 29 Nov 2021 18:26:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1379027AbhK2S36 (ORCPT ); Mon, 29 Nov 2021 13:29:58 -0500 Received: from sin.source.kernel.org ([145.40.73.55]:48764 "EHLO sin.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1378615AbhK2S1o (ORCPT ); Mon, 29 Nov 2021 13:27:44 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id 2BF3CCE13E6; Mon, 29 Nov 2021 18:24:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CA09EC53FAD; Mon, 29 Nov 2021 18:24:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1638210263; bh=rQhYkcav+ZpTGHy/dZz+gZ2BeaE9OME0op6o1I0+mHE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XZYWRkHFL7SkmW3AcIC+ujZuYxJLINUu6h2YHBF/QOl0avq8iW5y0SQXMEekJRkmg wsNEmsEIe+eDSBK4dASRqBp1YTIYl6xkM2BR5VxhTrbenRub03dpYtmJM2PusL1dF2 CEASFDKefV0QN/g2oMW52ScLvKLMqg0KdYSuQ1jE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tomasz Maciej Nowak , =?UTF-8?q?Pali=20Roh=C3=A1r?= , Lorenzo Pieralisi , Rob Herring , Thomas Petazzoni , =?UTF-8?q?Marek=20Beh=C3=BAn?= Subject: [PATCH 5.4 26/92] PCI: aardvark: Train link immediately after enabling training Date: Mon, 29 Nov 2021 19:17:55 +0100 Message-Id: <20211129181708.289743163@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211129181707.392764191@linuxfoundation.org> References: <20211129181707.392764191@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Pali Rohár commit 6964494582f56a3882c2c53b0edbfe99eb32b2e1 upstream. Adding even 100ms (PCI_PM_D3COLD_WAIT) delay between enabling link training and starting link training causes detection issues with some buggy cards (such as Compex WLE900VX). Move the code which enables link training immediately before the one which starts link traning. This fixes detection issues of Compex WLE900VX card on Turris MOX after cold boot. Link: https://lore.kernel.org/r/20200430080625.26070-2-pali@kernel.org Fixes: f4c7d053d7f7 ("PCI: aardvark: Wait for endpoint to be ready...") Tested-by: Tomasz Maciej Nowak Signed-off-by: Pali Rohár Signed-off-by: Lorenzo Pieralisi Acked-by: Rob Herring Acked-by: Thomas Petazzoni Signed-off-by: Marek Behún Signed-off-by: Greg Kroah-Hartman --- drivers/pci/controller/pci-aardvark.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) --- a/drivers/pci/controller/pci-aardvark.c +++ b/drivers/pci/controller/pci-aardvark.c @@ -394,11 +394,6 @@ static void advk_pcie_setup_hw(struct ad reg |= LANE_COUNT_1; advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG); - /* Enable link training */ - reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG); - reg |= LINK_TRAINING_EN; - advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG); - /* Enable MSI */ reg = advk_readl(pcie, PCIE_CORE_CTRL2_REG); reg |= PCIE_CORE_CTRL2_MSI_ENABLE; @@ -440,7 +435,15 @@ static void advk_pcie_setup_hw(struct ad */ msleep(PCI_PM_D3COLD_WAIT); - /* Start link training */ + /* Enable link training */ + reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG); + reg |= LINK_TRAINING_EN; + advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG); + + /* + * Start link training immediately after enabling it. + * This solves problems for some buggy cards. + */ reg = advk_readl(pcie, PCIE_CORE_LINK_CTRL_STAT_REG); reg |= PCIE_CORE_LINK_TRAINING; advk_writel(pcie, reg, PCIE_CORE_LINK_CTRL_STAT_REG);