diff options
| -rw-r--r-- | drivers/pci/msi/msi.c | 47 | ||||
| -rw-r--r-- | drivers/pci/pci.h | 9 |
2 files changed, 56 insertions, 0 deletions
diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c index 732166a9192c..593bae2855c3 100644 --- a/drivers/pci/msi/msi.c +++ b/drivers/pci/msi/msi.c @@ -913,6 +913,53 @@ void pci_free_msi_irqs(struct pci_dev *dev) } } +#ifdef CONFIG_PCIE_TPH +/** + * pci_msix_write_tph_tag - Update the TPH tag for a given MSI-X vector + * @pdev: The PCIe device to update + * @index: The MSI-X index to update + * @tag: The tag to write + * + * Returns: 0 on success, error code on failure + */ +int pci_msix_write_tph_tag(struct pci_dev *pdev, unsigned int index, u16 tag) +{ + struct msi_desc *msi_desc; + struct irq_desc *irq_desc; + unsigned int virq; + + if (!pdev->msix_enabled) + return -ENXIO; + + guard(msi_descs_lock)(&pdev->dev); + virq = msi_get_virq(&pdev->dev, index); + if (!virq) + return -ENXIO; + /* + * This is a horrible hack, but short of implementing a PCI + * specific interrupt chip callback and a huge pile of + * infrastructure, this is the minor nuissance. It provides the + * protection against concurrent operations on this entry and keeps + * the control word cache in sync. + */ + irq_desc = irq_to_desc(virq); + if (!irq_desc) + return -ENXIO; + + guard(raw_spinlock_irq)(&irq_desc->lock); + msi_desc = irq_data_get_msi_desc(&irq_desc->irq_data); + if (!msi_desc || msi_desc->pci.msi_attrib.is_virtual) + return -ENXIO; + + msi_desc->pci.msix_ctrl &= ~PCI_MSIX_ENTRY_CTRL_ST; + msi_desc->pci.msix_ctrl |= FIELD_PREP(PCI_MSIX_ENTRY_CTRL_ST, tag); + pci_msix_write_vector_ctrl(msi_desc, msi_desc->pci.msix_ctrl); + /* Flush the write */ + readl(pci_msix_desc_addr(msi_desc)); + return 0; +} +#endif + /* Misc. infrastructure */ struct pci_dev *msi_desc_to_pci_dev(struct msi_desc *desc) diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index b81e99cd4b62..39f368d2f26d 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -1064,6 +1064,15 @@ int pcim_request_region_exclusive(struct pci_dev *pdev, int bar, const char *name); void pcim_release_region(struct pci_dev *pdev, int bar); +#ifdef CONFIG_PCI_MSI +int pci_msix_write_tph_tag(struct pci_dev *pdev, unsigned int index, u16 tag); +#else +static inline int pci_msix_write_tph_tag(struct pci_dev *pdev, unsigned int index, u16 tag) +{ + return -ENODEV; +} +#endif + /* * Config Address for PCI Configuration Mechanism #1 * |