From aff171641d181ea573380efc3f559c9de4741fc5 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 12 Jul 2016 18:20:17 +0900 Subject: PCI: Provide sensible IRQ vector alloc/free routines Add a function to allocate and free a range of interrupt vectors, using MSI-X, MSI or legacy vectors (in that order) based on the capabilities of the underlying device and PCIe complex. Additionally a new helper is provided to get the Linux IRQ number for given device-relative vector so that the drivers don't need to allocate their own arrays to keep track of the vectors for the multi vector MSI-X case. Signed-off-by: Christoph Hellwig Signed-off-by: Bjorn Helgaas Reviewed-by: Alexander Gordeev --- include/linux/pci.h | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) (limited to 'include/linux') diff --git a/include/linux/pci.h b/include/linux/pci.h index b67e4df20801..52ecd49e8049 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1237,6 +1237,10 @@ resource_size_t pcibios_iov_resource_alignment(struct pci_dev *dev, int resno); int pci_set_vga_state(struct pci_dev *pdev, bool decode, unsigned int command_bits, u32 flags); +#define PCI_IRQ_NOLEGACY (1 << 0) /* don't use legacy interrupts */ +#define PCI_IRQ_NOMSI (1 << 1) /* don't use MSI interrupts */ +#define PCI_IRQ_NOMSIX (1 << 2) /* don't use MSI-X interrupts */ + /* kmem_cache style wrapper around pci_alloc_consistent() */ #include @@ -1284,6 +1288,11 @@ static inline int pci_enable_msix_exact(struct pci_dev *dev, return rc; return 0; } +int pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs, + unsigned int max_vecs, unsigned int flags); +void pci_free_irq_vectors(struct pci_dev *dev); +int pci_irq_vector(struct pci_dev *dev, unsigned int nr); + #else static inline int pci_msi_vec_count(struct pci_dev *dev) { return -ENOSYS; } static inline void pci_msi_shutdown(struct pci_dev *dev) { } @@ -1307,6 +1316,24 @@ static inline int pci_enable_msix_range(struct pci_dev *dev, static inline int pci_enable_msix_exact(struct pci_dev *dev, struct msix_entry *entries, int nvec) { return -ENOSYS; } +static inline int pci_alloc_irq_vectors(struct pci_dev *dev, + unsigned int min_vecs, unsigned int max_vecs, + unsigned int flags) +{ + if (min_vecs > 1) + return -EINVAL; + return 1; +} +static inline void pci_free_irq_vectors(struct pci_dev *dev) +{ +} + +static inline int pci_irq_vector(struct pci_dev *dev, unsigned int nr) +{ + if (WARN_ON_ONCE(nr > 0)) + return -EINVAL; + return dev->irq; +} #endif #ifdef CONFIG_PCIEPORTBUS -- cgit v1.2.3