PCI: aardvark: Disable link training when unbinding driver

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>

diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c
index 271ebec..e5c88f1 100644 (file)
--- a/drivers/pci/controller/pci-aardvark.c
+++ b/drivers/pci/controller/pci-aardvark.c
@@ -1741,6 +1741,11 @@ 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);