PCI: qcom: Remove DPC Extended Capability

Some platforms (e.g., X1E80100) expose Downstream Port Containment (DPC)
Extended Capability registers in the PCIe Root Port config space, but do
not fully support it. To prevent undefined behavior and ensure DPC cap is
not visible to PCI framework and users, remove DPC Extended Capability
unconditionally, since there is no Qcom platform support DPC till now.

Co-developed-by: Wenbin Yao <wenbin.yao@oss.qualcomm.com>
Signed-off-by: Wenbin Yao <wenbin.yao@oss.qualcomm.com>
Signed-off-by: Qiang Yu <qiang.yu@oss.qualcomm.com>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Link: https://patch.msgid.link/20251109-remove_cap-v1-5-2208f46f4dc2@oss.qualcomm.com

diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 8b8948fef386d927cf55f049521acb96ccbc4be5..60373fe1362f80d0112ee36119bc3c655448c94f 100644 (file)
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -1317,6 +1317,7 @@ static int qcom_pcie_host_init(struct dw_pcie_rp *pp)
        }
 
        dw_pcie_remove_capability(pcie->pci, PCI_CAP_ID_MSIX);
+       dw_pcie_remove_ext_capability(pcie->pci, PCI_EXT_CAP_ID_DPC);
 
        qcom_ep_reset_deassert(pcie);