From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Add pci_disable_parity() to disable reporting of parity errors for a device by clearing PCI_COMMAND_PARITY. The device will still set PCI_STATUS_DETECTED_PARITY when it detects a parity error or receives a Poisoned TLP, but it will not set PCI_STATUS_PARITY, which means it will not assert PERR# (conventional PCI) or report Poisoned TLPs (PCIe). Based-on: https://lore.kernel.org/linux-arm-kernel/d375987c-ea4f-dd98-4ef8-99b2fbfe7c33@xxxxxxxxx/ Based-on-patch-by: Heiner Kallweit <hkallweit1@xxxxxxxxx> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> --- drivers/pci/pci.c | 17 +++++++++++++++++ include/linux/pci.h | 1 + 2 files changed, 18 insertions(+) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 16a17215f633..b1845e5e5c8f 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -4453,6 +4453,23 @@ void pci_clear_mwi(struct pci_dev *dev) } EXPORT_SYMBOL(pci_clear_mwi); +/** + * pci_disable_parity - disable parity checking for device + * @dev: the PCI device to operate on + * + * Disable parity checking for device @dev + */ +void pci_disable_parity(struct pci_dev *dev) +{ + u16 cmd; + + pci_read_config_word(dev, PCI_COMMAND, &cmd); + if (cmd & PCI_COMMAND_PARITY) { + cmd &= ~PCI_COMMAND_PARITY; + pci_write_config_word(dev, PCI_COMMAND, cmd); + } +} + /** * pci_intx - enables/disables PCI INTx for device dev * @pdev: the PCI device to operate on diff --git a/include/linux/pci.h b/include/linux/pci.h index 86c799c97b77..4eaa773115da 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1201,6 +1201,7 @@ int __must_check pci_set_mwi(struct pci_dev *dev); int __must_check pcim_set_mwi(struct pci_dev *dev); int pci_try_set_mwi(struct pci_dev *dev); void pci_clear_mwi(struct pci_dev *dev); +void pci_disable_parity(struct pci_dev *dev); void pci_intx(struct pci_dev *dev, int enable); bool pci_check_and_mask_intx(struct pci_dev *dev); bool pci_check_and_unmask_intx(struct pci_dev *dev); -- 2.25.1
