From 2fd602669ee6d749a7dc47b84b87cef1a5075999 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 26 Aug 2020 13:16:53 +0200 Subject: PCI/MSI: Provide pci_dev_has_special_msi_domain() helper Provide a helper function to check whether a PCI device is handled by a non-standard PCI/MSI domain. This will be used to exclude such devices which hang of a special bus, e.g. VMD, to be excluded from the irq domain override in irq remapping. Signed-off-by: Thomas Gleixner Acked-by: Bjorn Helgaas Link: https://lore.kernel.org/r/20200826112333.139387358@linutronix.de --- drivers/pci/msi.c | 22 ++++++++++++++++++++++ include/linux/msi.h | 1 + 2 files changed, 23 insertions(+) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 744a1a4d2b32..a2f00d181016 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -1553,4 +1553,26 @@ struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev) DOMAIN_BUS_PCI_MSI); return dom; } + +/** + * pci_dev_has_special_msi_domain - Check whether the device is handled by + * a non-standard PCI-MSI domain + * @pdev: The PCI device to check. + * + * Returns: True if the device irqdomain or the bus irqdomain is + * non-standard PCI/MSI. + */ +bool pci_dev_has_special_msi_domain(struct pci_dev *pdev) +{ + struct irq_domain *dom = dev_get_msi_domain(&pdev->dev); + + if (!dom) + dom = dev_get_msi_domain(&pdev->bus->dev); + + if (!dom) + return true; + + return dom->bus_token != DOMAIN_BUS_PCI_MSI; +} + #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */ diff --git a/include/linux/msi.h b/include/linux/msi.h index 5aa126b7820b..a65cc47d0610 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -373,6 +373,7 @@ int pci_msi_domain_check_cap(struct irq_domain *domain, struct msi_domain_info *info, struct device *dev); u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev); struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev); +bool pci_dev_has_special_msi_domain(struct pci_dev *pdev); #else static inline struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev) { -- cgit v1.2.3-59-g8ed1b