diff options
| -rw-r--r-- | include/linux/msi.h | 45 | ||||
| -rw-r--r-- | kernel/irq/Kconfig | 10 | ||||
| -rw-r--r-- | kernel/irq/Makefile | 1 | ||||
| -rw-r--r-- | kernel/irq/msi.c | 141 |
4 files changed, 197 insertions, 0 deletions
diff --git a/include/linux/msi.h b/include/linux/msi.h index e0d08517bd3d..b5ca2456769c 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -114,4 +114,49 @@ struct msi_controller { void (*teardown_irq)(struct msi_controller *chip, unsigned int irq); }; +#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN +struct irq_domain; +struct irq_chip; +struct device_node; +struct msi_domain_info; + +/** + * struct msi_domain_ops - MSI interrupt domain callbacks + * @get_hwirq: Retrieve the resulting hw irq number + * @msi_init: Domain specific init function for MSI interrupts + * @msi_free: Domain specific function to free a MSI interrupts + */ +struct msi_domain_ops { + irq_hw_number_t (*get_hwirq)(struct msi_domain_info *info, void *arg); + int (*msi_init)(struct irq_domain *domain, + struct msi_domain_info *info, + unsigned int virq, irq_hw_number_t hwirq, + void *arg); + void (*msi_free)(struct irq_domain *domain, + struct msi_domain_info *info, + unsigned int virq); +}; + +/** + * struct msi_domain_info - MSI interrupt domain data + * @ops: The callback data structure + * @chip: The associated interrupt chip + * @data: Domain specific data + */ +struct msi_domain_info { + struct msi_domain_ops *ops; + struct irq_chip *chip; + void *data; +}; + +int msi_domain_set_affinity(struct irq_data *data, const struct cpumask *mask, + bool force); + +struct irq_domain *msi_create_irq_domain(struct device_node *of_node, + struct msi_domain_info *info, + struct irq_domain *parent); +struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain); + +#endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */ + #endif /* LINUX_MSI_H */ diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig index 4f2eb2b1f23b..9a76e3beda54 100644 --- a/kernel/irq/Kconfig +++ b/kernel/irq/Kconfig @@ -60,6 +60,16 @@ config IRQ_DOMAIN_HIERARCHY bool select IRQ_DOMAIN +# Generic MSI interrupt support +config GENERIC_MSI_IRQ + bool + +# Generic MSI hierarchical interrupt domain support +config GENERIC_MSI_IRQ_DOMAIN + bool + select IRQ_DOMAIN_HIERARCHY + select GENERIC_MSI_IRQ + config HANDLE_DOMAIN_IRQ bool diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile index fff17381f0af..d12123526e2b 100644 --- a/kernel/irq/Makefile +++ b/kernel/irq/Makefile @@ -6,3 +6,4 @@ obj-$(CONFIG_IRQ_DOMAIN) += irqdomain.o obj-$(CONFIG_PROC_FS) += proc.o obj-$(CONFIG_GENERIC_PENDING_IRQ) += migration.o obj-$(CONFIG_PM_SLEEP) += pm.o +obj-$(CONFIG_GENERIC_MSI_IRQ) += msi.o diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c new file mode 100644 index 000000000000..5e0cef4741d9 --- /dev/null +++ b/kernel/irq/msi.c @@ -0,0 +1,141 @@ +/* + * linux/kernel/irq/msi.c + * + * Copyright (C) 2014 Intel Corp. + * Author: Jiang Liu <jiang.liu@linux.intel.com> + * + * This file is licensed under GPLv2. + * + * This file contains common code to support Message Signalled Interrupt for + * PCI compatible and non PCI compatible devices. + */ +#include <linux/irq.h> +#include <linux/irqdomain.h> +#include <linux/msi.h> + +#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN +/** + * msi_domain_set_affinity - Generic affinity setter function for MSI domains + * @irq_data: The irq data associated to the interrupt + * @mask: The affinity mask to set + * @force: Flag to enforce setting (disable online checks) + * + * Intended to be used by MSI interrupt controllers which are + * implemented with hierarchical domains. + */ +int msi_domain_set_affinity(struct irq_data *irq_data, + const struct cpumask *mask, bool force) +{ + struct irq_data *parent = irq_data->parent_data; + struct msi_msg msg; + int ret; + + ret = parent->chip->irq_set_affinity(parent, mask, force); + if (ret >= 0 && ret != IRQ_SET_MASK_OK_DONE) { + BUG_ON(irq_chip_compose_msi_msg(irq_data, &msg)); + irq_chip_write_msi_msg(irq_data, &msg); + } + + return ret; +} + +static void msi_domain_activate(struct irq_domain *domain, + struct irq_data *irq_data) +{ + struct msi_msg msg; + + BUG_ON(irq_chip_compose_msi_msg(irq_data, &msg)); + irq_chip_write_msi_msg(irq_data, &msg); +} + +static void msi_domain_deactivate(struct irq_domain *domain, + struct irq_data *irq_data) +{ + struct msi_msg msg; + + memset(&msg, 0, sizeof(msg)); + irq_chip_write_msi_msg(irq_data, &msg); +} + +static int msi_domain_alloc(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs, void *arg) +{ + struct msi_domain_info *info = domain->host_data; + struct msi_domain_ops *ops = info->ops; + irq_hw_number_t hwirq = ops->get_hwirq(info, arg); + int i, ret; + + if (irq_find_mapping(domain, hwirq) > 0) + return -EEXIST; + + ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg); + if (ret < 0) + return ret; + + for (i = 0; i < nr_irqs; i++) { + ret = ops->msi_init(domain, info, virq + i, hwirq + i, arg); + if (ret < 0) { + if (ops->msi_free) { + for (i--; i > 0; i--) + ops->msi_free(domain, info, virq + i); + } + irq_domain_free_irqs_top(domain, virq, nr_irqs); + return ret; + } + } + + return 0; +} + +static void msi_domain_free(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs) +{ + struct msi_domain_info *info = domain->host_data; + int i; + + if (info->ops->msi_free) { + for (i = 0; i < nr_irqs; i++) + info->ops->msi_free(domain, info, virq + i); + } + irq_domain_free_irqs_top(domain, virq, nr_irqs); +} + +static struct irq_domain_ops msi_domain_ops = { + .alloc = msi_domain_alloc, + .free = msi_domain_free, + .activate = msi_domain_activate, + .deactivate = msi_domain_deactivate, +}; + +/** + * msi_create_irq_domain - Create a MSI interrupt domain + * @of_node: Optional device-tree node of the interrupt controller + * @info: MSI domain info + * @parent: Parent irq domain + */ +struct irq_domain *msi_create_irq_domain(struct device_node *of_node, + struct msi_domain_info *info, + struct irq_domain *parent) +{ + struct irq_domain *domain; + + domain = irq_domain_add_tree(of_node, &msi_domain_ops, info); + if (domain) + domain->parent = parent; + + return domain; +} + +/** + * msi_get_domain_info - Get the MSI interrupt domain info for @domain + * @domain: The interrupt domain to retrieve data from + * + * Returns the pointer to the msi_domain_info stored in + * @domain->host_data. + */ +struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain) +{ + return (struct msi_domain_info *)domain->host_data; +} + +#endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */ |