From: Pali Rohár Date: Wed, 24 Nov 2021 23:04:43 +0000 (+0100) Subject: PCI: aardvark: Train link immediately after enabling training X-Git-Tag: v4.19.219~51 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=0ca4db3676d5b667117bdbd4aef5c17c458bc061;p=users%2Fdwmw2%2Flinux.git PCI: aardvark: Train link immediately after enabling training 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 --- diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c index 3449d1444805e..4828d585d4b9e 100644 --- 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 advk_pcie *pcie) 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 advk_pcie *pcie) */ 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);