| /* |
| * 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, 0, 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 */ |