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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3C86BC433F5 for ; Mon, 29 Nov 2021 22:13:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232953AbhK2WRA (ORCPT ); Mon, 29 Nov 2021 17:17:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56552 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232020AbhK2WQn (ORCPT ); Mon, 29 Nov 2021 17:16:43 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 05714C127118; Mon, 29 Nov 2021 10:20:34 -0800 (PST) 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 52062CE13D8; Mon, 29 Nov 2021 18:20:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 01245C53FAD; Mon, 29 Nov 2021 18:20:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1638210030; bh=vT8IKzArOrvgvEbHzX1MnWtQ1B5U4f1mseNKlCyWNWk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=y2TnoN6yGsyzfKQMQK6sZW00uGCGChs381ERBPRdtwbfvLZnX1xrlTwBhDhajeeOj YTVUk1buHEZxFQ9TaZ93g71eWvD9MWPcmQHEy5CB5ZlOwRqySG23OhG3qs0UcFiqkb 1TfCQnhtQ6wjC84r05MdmgwUPpJUk1FP84LIHOtk= 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 4.19 19/69] PCI: aardvark: Train link immediately after enabling training Date: Mon, 29 Nov 2021 19:18:01 +0100 Message-Id: <20211129181704.294045464@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211129181703.670197996@linuxfoundation.org> References: <20211129181703.670197996@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 @@ -280,11 +280,6 @@ 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; @@ -326,7 +321,15 @@ 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);