This is a note to let you know that I've just added the patch titled PCI: aardvark: Train link immediately after enabling training to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: pci-aardvark-train-link-immediately-after-enabling-training.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Mon Nov 29 01:32:04 PM CET 2021 From: "Marek Behún" <kabel@xxxxxxxxxx> Date: Wed, 24 Nov 2021 23:49:13 +0100 Subject: PCI: aardvark: Train link immediately after enabling training To: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>, Sasha Levin <sashal@xxxxxxxxxx> Cc: pali@xxxxxxxxxx, stable@xxxxxxxxxxxxxxx, "Tomasz Maciej Nowak" <tmn505@xxxxxxxxx>, "Lorenzo Pieralisi" <lorenzo.pieralisi@xxxxxxx>, "Rob Herring" <robh@xxxxxxxxxx>, "Thomas Petazzoni" <thomas.petazzoni@xxxxxxxxxxx>, "Marek Behún" <kabel@xxxxxxxxxx> Message-ID: <20211124224933.24275-5-kabel@xxxxxxxxxx> From: Pali Rohár <pali@xxxxxxxxxx> 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@xxxxxxxxxx Fixes: f4c7d053d7f7 ("PCI: aardvark: Wait for endpoint to be ready...") Tested-by: Tomasz Maciej Nowak <tmn505@xxxxxxxxx> Signed-off-by: Pali Rohár <pali@xxxxxxxxxx> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> Acked-by: Rob Herring <robh@xxxxxxxxxx> Acked-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxx> Signed-off-by: Marek Behún <kabel@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/pci/host/pci-aardvark.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) --- a/drivers/pci/host/pci-aardvark.c +++ b/drivers/pci/host/pci-aardvark.c @@ -324,11 +324,6 @@ 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; @@ -370,7 +365,15 @@ 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); Patches currently in stable-queue which might be from kabel@xxxxxxxxxx are queue-4.14/pci-aardvark-move-pcie-reset-card-code-to-advk_pcie_train_link.patch queue-4.14/pci-aardvark-introduce-an-advk_pcie_valid_device-helper.patch queue-4.14/pci-aardvark-update-comment-about-disabling-link-training.patch queue-4.14/pci-aardvark-train-link-immediately-after-enabling-training.patch queue-4.14/arm64-dts-marvell-armada-37xx-declare-pcie-reset-pin.patch queue-4.14/pci-aardvark-replace-custom-macros-by-standard-linux-pci_regs.h-macros.patch queue-4.14/pci-aardvark-fix-a-leaked-reference-by-adding-missing-of_node_put.patch queue-4.14/pci-aardvark-fix-pcie-max-payload-size-setting.patch queue-4.14/pinctrl-armada-37xx-correct-pwm-pins-definitions.patch queue-4.14/arm64-dts-marvell-armada-37xx-set-pcie_reset_pin-to-gpio-function.patch queue-4.14/pci-aardvark-configure-pcie-resources-from-ranges-dt-property.patch queue-4.14/pci-aardvark-improve-link-training.patch queue-4.14/pci-aardvark-fix-link-training.patch queue-4.14/pci-aardvark-fix-checking-for-link-up-via-ltssm-state.patch queue-4.14/pci-aardvark-issue-perst-via-gpio.patch queue-4.14/pinctrl-armada-37xx-correct-mpp-definitions.patch queue-4.14/pci-add-pci_exp_lnkctl2_tls-macros.patch queue-4.14/pci-aardvark-wait-for-endpoint-to-be-ready-before-training-link.patch queue-4.14/pinctrl-armada-37xx-add-missing-pin-pcie1-wakeup.patch queue-4.14/pci-aardvark-fix-compilation-on-s390.patch queue-4.14/pci-aardvark-fix-i-o-space-page-leak.patch queue-4.14/pci-aardvark-don-t-touch-pcie-registers-if-no-card-connected.patch queue-4.14/pci-aardvark-remove-pcie-outbound-window-configuration.patch queue-4.14/pci-aardvark-indicate-error-in-val-when-config-read-fails.patch