diff options
| -rw-r--r-- | drivers/pci/msi/irqdomain.c | 22 | ||||
| -rw-r--r-- | drivers/pci/msi/msi.c | 4 | ||||
| -rw-r--r-- | drivers/pci/msi/msi.h | 9 |
3 files changed, 35 insertions, 0 deletions
diff --git a/drivers/pci/msi/irqdomain.c b/drivers/pci/msi/irqdomain.c index edd0cc204e06..666ed21f2924 100644 --- a/drivers/pci/msi/irqdomain.c +++ b/drivers/pci/msi/irqdomain.c @@ -187,6 +187,28 @@ struct irq_domain *pci_msi_create_irq_domain(struct fwnode_handle *fwnode, } EXPORT_SYMBOL_GPL(pci_msi_create_irq_domain); +/** + * pci_msi_domain_supports - Check for support of a particular feature flag + * @pdev: The PCI device to operate on + * @feature_mask: The feature mask to check for (full match) + * @mode: If ALLOW_LEGACY this grants the feature when there is no irq domain + * associated to the device. If DENY_LEGACY the lack of an irq domain + * makes the feature unsupported + */ +bool pci_msi_domain_supports(struct pci_dev *pdev, unsigned int feature_mask, + enum support_mode mode) +{ + struct msi_domain_info *info; + struct irq_domain *domain; + + domain = dev_get_msi_domain(&pdev->dev); + + if (!domain || !irq_domain_is_hierarchy(domain)) + return mode == ALLOW_LEGACY; + info = domain->host_data; + return (info->flags & feature_mask) == feature_mask; +} + /* * Users of the generic MSI infrastructure expect a device to have a single ID, * so with DMA aliases we have to pick the least-worst compromise. Devices with diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c index 794ec97c5b70..bc84647c6dbd 100644 --- a/drivers/pci/msi/msi.c +++ b/drivers/pci/msi/msi.c @@ -347,6 +347,10 @@ static int msi_capability_init(struct pci_dev *dev, int nvec, struct msi_desc *entry; int ret; + /* Reject multi-MSI early on irq domain enabled architectures */ + if (nvec > 1 && !pci_msi_domain_supports(dev, MSI_FLAG_MULTI_PCI_MSI, ALLOW_LEGACY)) + return 1; + /* * Disable MSI during setup in the hardware, but mark it enabled * so that setup code can evaluate it. diff --git a/drivers/pci/msi/msi.h b/drivers/pci/msi/msi.h index 8170ef2c5ad0..9d75b6fb3e0c 100644 --- a/drivers/pci/msi/msi.h +++ b/drivers/pci/msi/msi.h @@ -97,6 +97,15 @@ int __pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries, int void __pci_restore_msi_state(struct pci_dev *dev); void __pci_restore_msix_state(struct pci_dev *dev); +/* irq_domain related functionality */ + +enum support_mode { + ALLOW_LEGACY, + DENY_LEGACY, +}; + +bool pci_msi_domain_supports(struct pci_dev *dev, unsigned int feature_mask, enum support_mode mode); + /* Legacy (!IRQDOMAIN) fallbacks */ #ifdef CONFIG_PCI_MSI_ARCH_FALLBACKS |