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On some NXP chipsets, disabling Root Port MSI/MSI-X Capabilities blocks MSIs originating from Endpoints from reaching the iMSI-RX controller. To address this hardware bug, commit3a4e8302e7("PCI: imx6: Keep Root Port MSI capability with iMSI-RX to work around hardware bug") preserves Root Port MSI and MSI-X Capabilities on i.MX7D, i.MX8MM, and i.MX8MQ when iMSI-RX is in use. The same applies to i.MX6Q, i.MX6QP, and i.MX6SX, so preserve Root Port MSI/MSI-X Capabilities there as well. Note that preserving these Capabilities means Root Port-originated MSIs such as AER and PME won't be received due to separate hardware limitations. Users may need to use workarounds such as passing the 'pcie_pme=nomsi' command-line parameter. Fixes:f5cd8a929c("PCI: dwc: Remove MSI/MSIX capability for Root Port if iMSI-RX is used as MSI controller") Signed-off-by: Soeren Moch <smoch@web.de> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Frank Li <Frank.Li@nxp.com> Reviewed-by: Manivannan Sadhasivam <mani@kernel.org> Acked-by: Richard Zhu <hongxing.zhu@nxp.com> Cc: stable@vger.kernel.org # 7.0+ Link: https://patch.msgid.link/20260717033203.2965045-1-hongxing.zhu@oss.nxp.com