[PATCH 7.1 283/438] PCI: imx6: Keep i.MX6 Root Port MSI/MSI-X Capabilities with iMSI-RX to work around hardware bug
Greg Kroah-Hartman <[email protected]>
| Newsgroups | dev.linux.lists.patches,org.kernel.vger.stable |
|---|---|
| Message-ID | <[email protected]> |
7.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Soeren Moch <[email protected]> commit b4bee12ebeccfcd5959ace2c3a4af08f5a917d4c upstream. 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, commit 3a4e8302e72f ("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: f5cd8a929c825 ("PCI: dwc: Remove MSI/MSIX capability for Root Port if iMSI-RX is used as MSI controller") Signed-off-by: Soeren Moch <[email protected]> Signed-off-by: Richard Zhu <[email protected]> Signed-off-by: Bjorn Helgaas <[email protected]> Reviewed-by: Frank Li <[email protected]> Reviewed-by: Manivannan Sadhasivam <[email protected]> Acked-by: Richard Zhu <[email protected]> Cc: [email protected] # 7.0+ Link: https://patch.msgid.link/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/pci/controller/dwc/pci-imx6.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) --- a/drivers/pci/controller/dwc/pci-imx6.c +++ b/drivers/pci/controller/dwc/pci-imx6.c @@ -1884,7 +1884,8 @@ static const struct imx_pcie_drvdata drv .flags = IMX_PCIE_FLAG_IMX_PHY | IMX_PCIE_FLAG_SPEED_CHANGE_WORKAROUND | IMX_PCIE_FLAG_BROKEN_SUSPEND | - IMX_PCIE_FLAG_SUPPORTS_SUSPEND, + IMX_PCIE_FLAG_SUPPORTS_SUSPEND | + IMX_PCIE_FLAG_KEEP_MSI_CAP, .dbi_length = 0x200, .gpr = "fsl,imx6q-iomuxc-gpr", .ltssm_off = IOMUXC_GPR12, @@ -1900,7 +1901,8 @@ static const struct imx_pcie_drvdata drv .flags = IMX_PCIE_FLAG_IMX_PHY | IMX_PCIE_FLAG_SPEED_CHANGE_WORKAROUND | IMX_PCIE_FLAG_SKIP_L23_READY | - IMX_PCIE_FLAG_SUPPORTS_SUSPEND, + IMX_PCIE_FLAG_SUPPORTS_SUSPEND | + IMX_PCIE_FLAG_KEEP_MSI_CAP, .gpr = "fsl,imx6q-iomuxc-gpr", .ltssm_off = IOMUXC_GPR12, .ltssm_mask = IMX6Q_GPR12_PCIE_CTL_2, @@ -1915,7 +1917,8 @@ static const struct imx_pcie_drvdata drv .flags = IMX_PCIE_FLAG_IMX_PHY | IMX_PCIE_FLAG_SPEED_CHANGE_WORKAROUND | IMX_PCIE_FLAG_SKIP_L23_READY | - IMX_PCIE_FLAG_SUPPORTS_SUSPEND, + IMX_PCIE_FLAG_SUPPORTS_SUSPEND | + IMX_PCIE_FLAG_KEEP_MSI_CAP, .dbi_length = 0x200, .gpr = "fsl,imx6q-iomuxc-gpr", .ltssm_off = IOMUXC_GPR12,