Add tx term offset support to pcie qcom driver need in some revision of
the ipq806x SoC. Ipq8064 needs tx term offset set to 7.

Fixes: 82a823833f4e ("PCI: qcom: Add Qualcomm PCIe controller driver")
Signed-off-by: Sham Muthayyan <[email protected]>
Signed-off-by: Ansuel Smith <[email protected]>
Cc: [email protected] # v4.5+
---
 drivers/pci/controller/dwc/pcie-qcom.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pcie-qcom.c 
b/drivers/pci/controller/dwc/pcie-qcom.c
index f5398b0d270c..2cd6d1456210 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -45,6 +45,9 @@
 #define PCIE_CAP_CPL_TIMEOUT_DISABLE           0x10
 
 #define PCIE20_PARF_PHY_CTRL                   0x40
+#define PHY_CTRL_PHY_TX0_TERM_OFFSET_MASK      GENMASK(20, 16)
+#define PHY_CTRL_PHY_TX0_TERM_OFFSET(x)                ((x) << 16)
+
 #define PCIE20_PARF_PHY_REFCLK                 0x4C
 #define PHY_REFCLK_SSP_EN                      BIT(16)
 #define PHY_REFCLK_USE_PAD                     BIT(12)
@@ -374,9 +377,18 @@ static int qcom_pcie_init_2_1_0(struct qcom_pcie *pcie)
                writel(PHY_RX0_EQ(4), pcie->parf + PCIE20_PARF_CONFIG_BITS);
        }
 
+       if (of_device_is_compatible(node, "qcom,pcie-ipq8064")) {
+               /* set TX termination offset */
+               val = readl(pcie->parf + PCIE20_PARF_PHY_CTRL);
+               val &= ~PHY_CTRL_PHY_TX0_TERM_OFFSET_MASK;
+               val |= PHY_CTRL_PHY_TX0_TERM_OFFSET(7);
+               writel(val, pcie->parf + PCIE20_PARF_PHY_CTRL);
+       }
+
        /* enable external reference clock */
        val = readl(pcie->parf + PCIE20_PARF_PHY_REFCLK);
-       val |= BIT(16);
+       val &= ~PHY_REFCLK_USE_PAD;
+       val |= PHY_REFCLK_SSP_EN;
        writel(val, pcie->parf + PCIE20_PARF_PHY_REFCLK);
 
        /* wait for clock acquisition */
-- 
2.25.1

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