/* * 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/types.h> #include <linux/device.h> #include <linux/irq.h> #include <linux/irqdomain.h> #include <linux/msi.h> #include <linux/slab.h> /** * alloc_msi_entry - Allocate an initialize msi_entry * @dev: Pointer to the device for which this is allocated * @nvec: The number of vectors used in this entry * @affinity: Optional pointer to an affinity mask array size of @nvec * * If @affinity is not NULL then a an affinity array[@nvec] is allocated * and the affinity masks from @affinity are copied. */ struct msi_desc * alloc_msi_entry(struct device *dev, int nvec, const struct cpumask *affinity) { struct msi_desc *desc; desc = kzalloc(sizeof(*desc), GFP_KERNEL); if (!desc) return NULL; INIT_LIST_HEAD(&desc->list); desc->dev = dev; desc->nvec_used = nvec; if (affinity) { desc->affinity = kmemdup(affinity, nvec * sizeof(*desc->affinity), GFP_KERNEL); if (!desc->affinity) { kfree(desc); return NULL; } } return desc; } void free_msi_entry(struct msi_desc *entry) { kfree(entry->affinity); kfree(entry); } void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg) { *msg = entry->msg; } void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg) { struct msi_desc *entry = irq_get_msi_desc(irq); __get_cached_msi_msg(entry, msg); } EXPORT_SYMBOL_GPL(get_cached_msi_msg); #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN static inline void irq_chip_write_msi_msg(struct irq_data *data, struct msi_msg *msg) { data->chip->irq_write_msi_msg(data, msg); } /** * 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; if (domain->parent) { 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 const struct irq_domain_ops msi_domain_ops = { .alloc = msi_domain_alloc, .free = msi_domain_free, .activate = msi_domain_activate, .deactivate = msi_domain_deactivate, }; #ifdef GENERIC_MSI_DOMAIN_OPS static irq_hw_number_t msi_domain_ops_get_hwirq(struct msi_domain_info *info, msi_alloc_info_t *arg) { return arg->hwirq; } static int msi_domain_ops_prepare(struct irq_domain *domain, struct device *dev, int nvec, msi_alloc_info_t *arg) { memset(arg, 0, sizeof(*arg)); return 0; } static void msi_domain_ops_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc) { arg->desc = desc; } #else #define msi_domain_ops_get_hwirq NULL #define msi_domain_ops_prepare NULL #define msi_domain_ops_set_desc NULL #endif /* !GENERIC_MSI_DOMAIN_OPS */ static int msi_domain_ops_init(struct irq_domain *domain, struct msi_domain_info *info, unsigned int virq, irq_hw_number_t hwirq, msi_alloc_info_t *arg) { irq_domain_set_hwirq_and_chip(domain, virq, hwirq, info->chip, info->chip_data); if (info->handler && info->handler_name) { __irq_set_handler(virq, info->handler, 0, info->handler_name); if (info->handler_data) irq_set_handler_data(virq, info->handler_data); } return 0; } static int msi_domain_ops_check(struct irq_domain *domain, struct msi_domain_info *info, struct device *dev) { return 0; } static struct msi_domain_ops msi_domain_ops_default = { .get_hwirq = msi_domain_ops_get_hwirq, .msi_init = msi_domain_ops_init, .msi_check = msi_domain_ops_check, .msi_prepare = msi_domain_ops_prepare, .set_desc = msi_domain_ops_set_desc, }; static void msi_domain_update_dom_ops(struct msi_domain_info *info) { struct msi_domain_ops *ops = info->ops; if (ops == NULL) { info->ops = &msi_domain_ops_default; return; } if (ops->get_hwirq == NULL) ops->get_hwirq = msi_domain_ops_default.get_hwirq; if (ops->msi_init == NULL) ops->msi_init = msi_domain_ops_default.msi_init; if (ops->msi_check == NULL) ops->msi_check = msi_domain_ops_default.msi_check; if (ops->msi_prepare == NULL) ops->msi_prepare = msi_domain_ops_default.msi_prepare; if (ops->set_desc == NULL) ops->set_desc = msi_domain_ops_default.set_desc; } static void msi_domain_update_chip_ops(struct msi_domain_info *info) { struct irq_chip *chip = info->chip; BUG_ON(!chip || !chip->irq_mask || !chip->irq_unmask); if (!chip->irq_set_affinity) chip->irq_set_affinity = msi_domain_set_affinity; } /** * msi_create_irq_domain - Create a MSI interrupt domain * @fwnode: Optional fwnode of the interrupt controller * @info: MSI domain info * @parent: Parent irq domain */ struct irq_domain *msi_create_irq_domain(struct fwnode_handle *fwnode, struct msi_domain_info *info, struct irq_domain *parent) { if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS) msi_domain_update_dom_ops(info); if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS) msi_domain_update_chip_ops(info); return irq_domain_create_hierarchy(parent, IRQ_DOMAIN_FLAG_MSI, 0, fwnode, &msi_domain_ops, info); } int msi_domain_prepare_irqs(struct irq_domain *domain, struct device *dev, int nvec, msi_alloc_info_t *arg) { struct msi_domain_info *info = domain->host_data; struct msi_domain_ops *ops = info->ops; int ret; ret = ops->msi_check(domain, info, dev); if (ret == 0) ret = ops->msi_prepare(domain, dev, nvec, arg); return ret; } int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev, int virq, int nvec, msi_alloc_info_t *arg) { struct msi_domain_info *info = domain->host_data; struct msi_domain_ops *ops = info->ops; struct msi_desc *desc; int ret = 0; for_each_msi_entry(desc, dev) { /* Don't even try the multi-MSI brain damage. */ if (WARN_ON(!desc->irq || desc->nvec_used != 1)) { ret = -EINVAL; break; } if (!(desc->irq >= virq && desc->irq < (virq + nvec))) continue; ops->set_desc(arg, desc); /* Assumes the domain mutex is held! */ ret = irq_domain_alloc_irqs_recursive(domain, virq, 1, arg); if (ret) break; irq_set_msi_desc_off(virq, 0, desc); } if (ret) { /* Mop up the damage */ for_each_msi_entry(desc, dev) { if (!(desc->irq >= virq && desc->irq < (virq + nvec))) continue; irq_domain_free_irqs_common(domain, desc->irq, 1); } } return ret; } /** * msi_domain_alloc_irqs - Allocate interrupts from a MSI interrupt domain * @domain: The domain to allocate from * @dev: Pointer to device struct of the device for which the interrupts * are allocated * @nvec: The number of interrupts to allocate * * Returns 0 on success or an error code. */ int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev, int nvec) { struct msi_domain_info *info = domain->host_data; struct msi_domain_ops *ops = info->ops; msi_alloc_info_t arg; struct msi_desc *desc; int i, ret, virq; ret = msi_domain_prepare_irqs(domain, dev, nvec, &arg); if (ret) return ret; for_each_msi_entry(desc, dev) { ops->set_desc(&arg, desc); virq = __irq_domain_alloc_irqs(domain, -1, desc->nvec_used, dev_to_node(dev), &arg, false, desc->affinity); if (virq < 0) { ret = -ENOSPC; if (ops->handle_error) ret = ops->handle_error(domain, desc, ret); if (ops->msi_finish) ops->msi_finish(&arg, ret); return ret; } for (i = 0; i < desc->nvec_used; i++) irq_set_msi_desc_off(virq, i, desc); } if (ops->msi_finish) ops->msi_finish(&arg, 0); for_each_msi_entry(desc, dev) { virq = desc->irq; if (desc->nvec_used == 1) dev_dbg(dev, "irq %d for MSI\n", virq); else dev_dbg(dev, "irq [%d-%d] for MSI\n", virq, virq + desc->nvec_used - 1); /* * This flag is set by the PCI layer as we need to activate * the MSI entries before the PCI layer enables MSI in the * card. Otherwise the card latches a random msi message. */ if (info->flags & MSI_FLAG_ACTIVATE_EARLY) { struct irq_data *irq_data; irq_data = irq_domain_get_irq_data(domain, desc->irq); irq_domain_activate_irq(irq_data); } } return 0; } /** * msi_domain_free_irqs - Free interrupts from a MSI interrupt @domain associated tp @dev * @domain: The domain to managing the interrupts * @dev: Pointer to device struct of the device for which the interrupts * are free */ void msi_domain_free_irqs(struct irq_domain *domain, struct device *dev) { struct msi_desc *desc; for_each_msi_entry(desc, dev) { /* * We might have failed to allocate an MSI early * enough that there is no IRQ associated to this * entry. If that's the case, don't do anything. */ if (desc->irq) { irq_domain_free_irqs(desc->irq, desc->nvec_used); desc->irq = 0; } } } /** * 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 */