PCI: aardvark: Disable link training when unbinding driver

commit 759dec2e3dfdbd261c41d2279f04f2351c971a49 upstream.

Disable link training circuit in driver unbind sequence. We want to
leave link training in the same state as it was before the driver was
probed.

Link: https://lore.kernel.org/r/20211130172913.9727-11-kabel@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c
index 78bc57d..3f69195 100644 (file)
--- a/drivers/pci/controller/pci-aardvark.c
+++ b/drivers/pci/controller/pci-aardvark.c
@@ -1725,6 +1725,11 @@ static int advk_pcie_remove(struct platform_device *pdev)
        if (pcie->reset_gpio)
                gpiod_set_value_cansleep(pcie->reset_gpio, 1);
 
+       /* Disable link training */
+       val = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
+       val &= ~LINK_TRAINING_EN;
+       advk_writel(pcie, val, PCIE_CORE_CTRL0_REG);
+
        /* Disable outbound address windows mapping */
        for (i = 0; i < OB_WIN_COUNT; i++)
                advk_pcie_disable_ob_win(pcie, i);