PCI: qcom: Use PHY_REFCLK_USE_PAD only for ipq8064

commit 2cfef1971aea6119ee27429181d6cb3383031ac2 upstream.

The use of PHY_REFCLK_USE_PAD introduced a regression for apq8064 devices.
It was tested that while apq doesn't require the padding, ipq SoC must use
it or the kernel hangs on boot.

Link: https://lore.kernel.org/r/20201019165555.8269-1-ansuelsmth@gmail.com
Fixes: de3c4bf64897 ("PCI: qcom: Add support for tx term offset for rev 2.1.0")
Reported-by: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Stanimir Varbanov <svarbanov@mm-sol.com>
Cc: stable@vger.kernel.org	# v4.19+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 14196c0287a245cd6e107e97e672cb94fb79339d..a8eab4e67af10f0f25df222444d4add240473451 100644 (file)
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -402,7 +402,9 @@ static int qcom_pcie_init_2_1_0(struct qcom_pcie *pcie)
 
        /* enable external reference clock */
        val = readl(pcie->parf + PCIE20_PARF_PHY_REFCLK);
-       val &= ~PHY_REFCLK_USE_PAD;
+       /* USE_PAD is required only for ipq806x */
+       if (!of_device_is_compatible(node, "qcom,pcie-apq8064"))
+               val &= ~PHY_REFCLK_USE_PAD;
        val |= PHY_REFCLK_SSP_EN;
        writel(val, pcie->parf + PCIE20_PARF_PHY_REFCLK);