From: Qiang Yu Date: Mon, 10 Nov 2025 06:59:43 +0000 (-0800) Subject: PCI: qcom: Remove MSI-X Capability for Root Ports X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7c29cd0fdc07e5e21202fdeed0b63cba2b4f10c6;p=thirdparty%2Fkernel%2Flinux.git PCI: qcom: Remove MSI-X Capability for Root Ports On some platforms like Glymur, the hardware does not support MSI-X in RC mode, yet still exposes the MSI-X capability. However, it omits the required MSI-X Table and PBA structures. This mismatch can lead to issues where the PCIe port driver requests MSI-X instead of MSI, causing the Root Port to trigger interrupts by writing to an uninitialized address, resulting in SMMU faults. To address this, remove MSI-X capability unconditionally for Root Ports of all SoCs as none of the Qcom PCIe Root Ports support MSI-X. Signed-off-by: Qiang Yu [mani: updated description] Signed-off-by: Manivannan Sadhasivam Link: https://patch.msgid.link/20251109-remove_cap-v1-4-2208f46f4dc2@oss.qualcomm.com --- diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c index 7b92e7a1c0d93..8b8948fef386d 100644 --- a/drivers/pci/controller/dwc/pcie-qcom.c +++ b/drivers/pci/controller/dwc/pcie-qcom.c @@ -1316,6 +1316,8 @@ static int qcom_pcie_host_init(struct dw_pcie_rp *pp) goto err_disable_phy; } + dw_pcie_remove_capability(pcie->pci, PCI_CAP_ID_MSIX); + qcom_ep_reset_deassert(pcie); if (pcie->cfg->ops->config_sid) {