[PATCH v4 1/3] PCI: Add pci_disable_parity()
From: Bjorn Helgaas <helgaas@kernel.org>
Date: 2021-03-30 17:45:18
Also in:
linux-arm-kernel, linux-pci
Subsystem:
pci subsystem, the rest · Maintainers:
Bjorn Helgaas, Linus Torvalds
From: Bjorn Helgaas <bhelgaas@google.com> 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@gmail.com/ (local) Based-on-patch-by: Heiner Kallweit [off-list ref] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> --- 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