[PATCH v7 2/9] PCI: tegra194: Calibrate P2U for Endpoint mode

From: Manikanta Maddireddy

Date: Tue Mar 03 2026 - 02:00:35 EST


From: Vidya Sagar <vidyas@xxxxxxxxxx>

Calibrate P2U for Endpoint controller to request UPHY PLL rate change to
Gen1 during initialization. This helps to reset stale PLL state from the
previous bad link state.

Reviewed-by: Jon Hunter <jonathanh@xxxxxxxxxx>
Tested-by: Jon Hunter <jonathanh@xxxxxxxxxx>
Signed-off-by: Vidya Sagar <vidyas@xxxxxxxxxx>
Signed-off-by: Manikanta Maddireddy <mmaddireddy@xxxxxxxxxx>
---
Changes V1 -> V7: None

drivers/pci/controller/dwc/pcie-tegra194.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index 2f1f882fc737..980988b7499c 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -1054,6 +1054,9 @@ static int tegra_pcie_enable_phy(struct tegra_pcie_dw *pcie)
ret = phy_power_on(pcie->phys[i]);
if (ret < 0)
goto phy_exit;
+
+ if (pcie->of_data->mode == DW_PCIE_EP_TYPE)
+ phy_calibrate(pcie->phys[i]);
}

return 0;
--
2.34.1