diff options
| -rw-r--r-- | drivers/pci/Kconfig | 5 | ||||
| -rw-r--r-- | drivers/pci/msi.c | 168 | ||||
| -rw-r--r-- | include/linux/msi.h | 14 |
3 files changed, 187 insertions, 0 deletions
diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig index 82f95f4512f8..cced84233ac0 100644 --- a/drivers/pci/Kconfig +++ b/drivers/pci/Kconfig @@ -17,6 +17,11 @@ config PCI_MSI If you don't know what to do here, say Y. +config PCI_MSI_IRQ_DOMAIN + bool + depends on PCI_MSI + select GENERIC_MSI_IRQ_DOMAIN + config PCI_DEBUG bool "PCI Debugging" depends on PCI && DEBUG_KERNEL diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 103700e127bf..36b0c2e55929 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -19,6 +19,7 @@ #include <linux/errno.h> #include <linux/io.h> #include <linux/slab.h> +#include <linux/irqdomain.h> #include "pci.h" @@ -1091,3 +1092,170 @@ int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries, return nvec; } EXPORT_SYMBOL(pci_enable_msix_range); + +#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN +/** + * pci_msi_domain_write_msg - Helper to write MSI message to PCI config space + * @irq_data: Pointer to interrupt data of the MSI interrupt + * @msg: Pointer to the message + */ +void pci_msi_domain_write_msg(struct irq_data *irq_data, struct msi_msg *msg) +{ + struct msi_desc *desc = irq_data->msi_desc; + + /* + * For MSI-X desc->irq is always equal to irq_data->irq. For + * MSI only the first interrupt of MULTI MSI passes the test. + */ + if (desc->irq == irq_data->irq) + __pci_write_msi_msg(desc, msg); +} + +/** + * pci_msi_domain_calc_hwirq - Generate a unique ID for an MSI source + * @dev: Pointer to the PCI device + * @desc: Pointer to the msi descriptor + * + * The ID number is only used within the irqdomain. + */ +irq_hw_number_t pci_msi_domain_calc_hwirq(struct pci_dev *dev, + struct msi_desc *desc) +{ + return (irq_hw_number_t)desc->msi_attrib.entry_nr | + PCI_DEVID(dev->bus->number, dev->devfn) << 11 | + (pci_domain_nr(dev->bus) & 0xFFFFFFFF) << 27; +} + +static inline bool pci_msi_desc_is_multi_msi(struct msi_desc *desc) +{ + return !desc->msi_attrib.is_msix && desc->nvec_used > 1; +} + +/** + * pci_msi_domain_check_cap - Verify that @domain supports the capabilities for @dev + * @domain: The interrupt domain to check + * @info: The domain info for verification + * @dev: The device to check + * + * Returns: + * 0 if the functionality is supported + * 1 if Multi MSI is requested, but the domain does not support it + * -ENOTSUPP otherwise + */ +int pci_msi_domain_check_cap(struct irq_domain *domain, + struct msi_domain_info *info, struct device *dev) +{ + struct msi_desc *desc = first_pci_msi_entry(to_pci_dev(dev)); + + /* Special handling to support pci_enable_msi_range() */ + if (pci_msi_desc_is_multi_msi(desc) && + !(info->flags & MSI_FLAG_MULTI_PCI_MSI)) + return 1; + else if (desc->msi_attrib.is_msix && !(info->flags & MSI_FLAG_PCI_MSIX)) + return -ENOTSUPP; + + return 0; +} + +static int pci_msi_domain_handle_error(struct irq_domain *domain, + struct msi_desc *desc, int error) +{ + /* Special handling to support pci_enable_msi_range() */ + if (pci_msi_desc_is_multi_msi(desc) && error == -ENOSPC) + return 1; + + return error; +} + +#ifdef GENERIC_MSI_DOMAIN_OPS +static void pci_msi_domain_set_desc(msi_alloc_info_t *arg, + struct msi_desc *desc) +{ + arg->desc = desc; + arg->hwirq = pci_msi_domain_calc_hwirq(msi_desc_to_pci_dev(desc), + desc); +} +#else +#define pci_msi_domain_set_desc NULL +#endif + +static struct msi_domain_ops pci_msi_domain_ops_default = { + .set_desc = pci_msi_domain_set_desc, + .msi_check = pci_msi_domain_check_cap, + .handle_error = pci_msi_domain_handle_error, +}; + +static void pci_msi_domain_update_dom_ops(struct msi_domain_info *info) +{ + struct msi_domain_ops *ops = info->ops; + + if (ops == NULL) { + info->ops = &pci_msi_domain_ops_default; + } else { + if (ops->set_desc == NULL) + ops->set_desc = pci_msi_domain_set_desc; + if (ops->msi_check == NULL) + ops->msi_check = pci_msi_domain_check_cap; + if (ops->handle_error == NULL) + ops->handle_error = pci_msi_domain_handle_error; + } +} + +static void pci_msi_domain_update_chip_ops(struct msi_domain_info *info) +{ + struct irq_chip *chip = info->chip; + + BUG_ON(!chip); + if (!chip->irq_write_msi_msg) + chip->irq_write_msi_msg = pci_msi_domain_write_msg; +} + +/** + * pci_msi_create_irq_domain - Creat a MSI interrupt domain + * @node: Optional device-tree node of the interrupt controller + * @info: MSI domain info + * @parent: Parent irq domain + * + * Updates the domain and chip ops and creates a MSI interrupt domain. + * + * Returns: + * A domain pointer or NULL in case of failure. + */ +struct irq_domain *pci_msi_create_irq_domain(struct device_node *node, + struct msi_domain_info *info, + struct irq_domain *parent) +{ + if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS) + pci_msi_domain_update_dom_ops(info); + if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS) + pci_msi_domain_update_chip_ops(info); + + return msi_create_irq_domain(node, info, parent); +} + +/** + * pci_msi_domain_alloc_irqs - Allocate interrupts for @dev in @domain + * @domain: The interrupt domain to allocate from + * @dev: The device for which to allocate + * @nvec: The number of interrupts to allocate + * @type: Unused to allow simpler migration from the arch_XXX interfaces + * + * Returns: + * A virtual interrupt number or an error code in case of failure + */ +int pci_msi_domain_alloc_irqs(struct irq_domain *domain, struct pci_dev *dev, + int nvec, int type) +{ + return msi_domain_alloc_irqs(domain, &dev->dev, nvec); +} + +/** + * pci_msi_domain_free_irqs - Free interrupts for @dev in @domain + * @domain: The interrupt domain + * @dev: The device for which to free interrupts + */ +void pci_msi_domain_free_irqs(struct irq_domain *domain, struct pci_dev *dev) +{ + msi_domain_free_irqs(domain, &dev->dev); +} +#endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */ diff --git a/include/linux/msi.h b/include/linux/msi.h index 0098e2c8fd42..1628788aee25 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -220,4 +220,18 @@ struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain); #endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */ +#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN +void pci_msi_domain_write_msg(struct irq_data *irq_data, struct msi_msg *msg); +struct irq_domain *pci_msi_create_irq_domain(struct device_node *node, + struct msi_domain_info *info, + struct irq_domain *parent); +int pci_msi_domain_alloc_irqs(struct irq_domain *domain, struct pci_dev *dev, + int nvec, int type); +void pci_msi_domain_free_irqs(struct irq_domain *domain, struct pci_dev *dev); +irq_hw_number_t pci_msi_domain_calc_hwirq(struct pci_dev *dev, + struct msi_desc *desc); +int pci_msi_domain_check_cap(struct irq_domain *domain, + struct msi_domain_info *info, struct device *dev); +#endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */ + #endif /* LINUX_MSI_H */ |