diff options
Diffstat (limited to 'kernel/irq/msi.c')
| -rw-r--r-- | kernel/irq/msi.c | 1042 |
1 files changed, 1042 insertions, 0 deletions
diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c new file mode 100644 index 000000000..4e462b5f7 --- /dev/null +++ b/kernel/irq/msi.c @@ -0,0 +1,1042 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * 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 Signaled Interrupts 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> +#include <linux/sysfs.h> +#include <linux/pci.h> + +#include "internals.h" + +static inline int msi_sysfs_create_group(struct device *dev); + +/** + * msi_alloc_desc - Allocate an initialized msi_desc + * @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 an affinity array[@nvec] is allocated + * and the affinity masks and flags from @affinity are copied. + * + * Return: pointer to allocated &msi_desc on success or %NULL on failure + */ +static struct msi_desc *msi_alloc_desc(struct device *dev, int nvec, + const struct irq_affinity_desc *affinity) +{ + struct msi_desc *desc = kzalloc(sizeof(*desc), GFP_KERNEL); + + if (!desc) + return NULL; + + 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; +} + +static void msi_free_desc(struct msi_desc *desc) +{ + kfree(desc->affinity); + kfree(desc); +} + +static int msi_insert_desc(struct msi_device_data *md, struct msi_desc *desc, unsigned int index) +{ + int ret; + + desc->msi_index = index; + ret = xa_insert(&md->__store, index, desc, GFP_KERNEL); + if (ret) + msi_free_desc(desc); + return ret; +} + +/** + * msi_add_msi_desc - Allocate and initialize a MSI descriptor + * @dev: Pointer to the device for which the descriptor is allocated + * @init_desc: Pointer to an MSI descriptor to initialize the new descriptor + * + * Return: 0 on success or an appropriate failure code. + */ +int msi_add_msi_desc(struct device *dev, struct msi_desc *init_desc) +{ + struct msi_desc *desc; + + lockdep_assert_held(&dev->msi.data->mutex); + + desc = msi_alloc_desc(dev, init_desc->nvec_used, init_desc->affinity); + if (!desc) + return -ENOMEM; + + /* Copy type specific data to the new descriptor. */ + desc->pci = init_desc->pci; + return msi_insert_desc(dev->msi.data, desc, init_desc->msi_index); +} + +/** + * msi_add_simple_msi_descs - Allocate and initialize MSI descriptors + * @dev: Pointer to the device for which the descriptors are allocated + * @index: Index for the first MSI descriptor + * @ndesc: Number of descriptors to allocate + * + * Return: 0 on success or an appropriate failure code. + */ +static int msi_add_simple_msi_descs(struct device *dev, unsigned int index, unsigned int ndesc) +{ + unsigned int idx, last = index + ndesc - 1; + struct msi_desc *desc; + int ret; + + lockdep_assert_held(&dev->msi.data->mutex); + + for (idx = index; idx <= last; idx++) { + desc = msi_alloc_desc(dev, 1, NULL); + if (!desc) + goto fail_mem; + ret = msi_insert_desc(dev->msi.data, desc, idx); + if (ret) + goto fail; + } + return 0; + +fail_mem: + ret = -ENOMEM; +fail: + msi_free_msi_descs_range(dev, MSI_DESC_NOTASSOCIATED, index, last); + return ret; +} + +static bool msi_desc_match(struct msi_desc *desc, enum msi_desc_filter filter) +{ + switch (filter) { + case MSI_DESC_ALL: + return true; + case MSI_DESC_NOTASSOCIATED: + return !desc->irq; + case MSI_DESC_ASSOCIATED: + return !!desc->irq; + } + WARN_ON_ONCE(1); + return false; +} + +/** + * msi_free_msi_descs_range - Free MSI descriptors of a device + * @dev: Device to free the descriptors + * @filter: Descriptor state filter + * @first_index: Index to start freeing from + * @last_index: Last index to be freed + */ +void msi_free_msi_descs_range(struct device *dev, enum msi_desc_filter filter, + unsigned int first_index, unsigned int last_index) +{ + struct xarray *xa = &dev->msi.data->__store; + struct msi_desc *desc; + unsigned long idx; + + lockdep_assert_held(&dev->msi.data->mutex); + + xa_for_each_range(xa, idx, desc, first_index, last_index) { + if (msi_desc_match(desc, filter)) { + xa_erase(xa, idx); + msi_free_desc(desc); + } + } +} + +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); + +static void msi_device_data_release(struct device *dev, void *res) +{ + struct msi_device_data *md = res; + + WARN_ON_ONCE(!xa_empty(&md->__store)); + xa_destroy(&md->__store); + dev->msi.data = NULL; +} + +/** + * msi_setup_device_data - Setup MSI device data + * @dev: Device for which MSI device data should be set up + * + * Return: 0 on success, appropriate error code otherwise + * + * This can be called more than once for @dev. If the MSI device data is + * already allocated the call succeeds. The allocated memory is + * automatically released when the device is destroyed. + */ +int msi_setup_device_data(struct device *dev) +{ + struct msi_device_data *md; + int ret; + + if (dev->msi.data) + return 0; + + md = devres_alloc(msi_device_data_release, sizeof(*md), GFP_KERNEL); + if (!md) + return -ENOMEM; + + ret = msi_sysfs_create_group(dev); + if (ret) { + devres_free(md); + return ret; + } + + xa_init(&md->__store); + mutex_init(&md->mutex); + dev->msi.data = md; + devres_add(dev, md); + return 0; +} + +/** + * msi_lock_descs - Lock the MSI descriptor storage of a device + * @dev: Device to operate on + */ +void msi_lock_descs(struct device *dev) +{ + mutex_lock(&dev->msi.data->mutex); +} +EXPORT_SYMBOL_GPL(msi_lock_descs); + +/** + * msi_unlock_descs - Unlock the MSI descriptor storage of a device + * @dev: Device to operate on + */ +void msi_unlock_descs(struct device *dev) +{ + /* Invalidate the index wich was cached by the iterator */ + dev->msi.data->__iter_idx = MSI_MAX_INDEX; + mutex_unlock(&dev->msi.data->mutex); +} +EXPORT_SYMBOL_GPL(msi_unlock_descs); + +static struct msi_desc *msi_find_desc(struct msi_device_data *md, enum msi_desc_filter filter) +{ + struct msi_desc *desc; + + xa_for_each_start(&md->__store, md->__iter_idx, desc, md->__iter_idx) { + if (msi_desc_match(desc, filter)) + return desc; + } + md->__iter_idx = MSI_MAX_INDEX; + return NULL; +} + +/** + * msi_first_desc - Get the first MSI descriptor of a device + * @dev: Device to operate on + * @filter: Descriptor state filter + * + * Must be called with the MSI descriptor mutex held, i.e. msi_lock_descs() + * must be invoked before the call. + * + * Return: Pointer to the first MSI descriptor matching the search + * criteria, NULL if none found. + */ +struct msi_desc *msi_first_desc(struct device *dev, enum msi_desc_filter filter) +{ + struct msi_device_data *md = dev->msi.data; + + if (WARN_ON_ONCE(!md)) + return NULL; + + lockdep_assert_held(&md->mutex); + + md->__iter_idx = 0; + return msi_find_desc(md, filter); +} +EXPORT_SYMBOL_GPL(msi_first_desc); + +/** + * msi_next_desc - Get the next MSI descriptor of a device + * @dev: Device to operate on + * + * The first invocation of msi_next_desc() has to be preceeded by a + * successful invocation of __msi_first_desc(). Consecutive invocations are + * only valid if the previous one was successful. All these operations have + * to be done within the same MSI mutex held region. + * + * Return: Pointer to the next MSI descriptor matching the search + * criteria, NULL if none found. + */ +struct msi_desc *msi_next_desc(struct device *dev, enum msi_desc_filter filter) +{ + struct msi_device_data *md = dev->msi.data; + + if (WARN_ON_ONCE(!md)) + return NULL; + + lockdep_assert_held(&md->mutex); + + if (md->__iter_idx >= (unsigned long)MSI_MAX_INDEX) + return NULL; + + md->__iter_idx++; + return msi_find_desc(md, filter); +} +EXPORT_SYMBOL_GPL(msi_next_desc); + +/** + * msi_get_virq - Return Linux interrupt number of a MSI interrupt + * @dev: Device to operate on + * @index: MSI interrupt index to look for (0-based) + * + * Return: The Linux interrupt number on success (> 0), 0 if not found + */ +unsigned int msi_get_virq(struct device *dev, unsigned int index) +{ + struct msi_desc *desc; + unsigned int ret = 0; + bool pcimsi; + + if (!dev->msi.data) + return 0; + + pcimsi = dev_is_pci(dev) ? to_pci_dev(dev)->msi_enabled : false; + + msi_lock_descs(dev); + desc = xa_load(&dev->msi.data->__store, pcimsi ? 0 : index); + if (desc && desc->irq) { + /* + * PCI-MSI has only one descriptor for multiple interrupts. + * PCI-MSIX and platform MSI use a descriptor per + * interrupt. + */ + if (pcimsi) { + if (index < desc->nvec_used) + ret = desc->irq + index; + } else { + ret = desc->irq; + } + } + msi_unlock_descs(dev); + return ret; +} +EXPORT_SYMBOL_GPL(msi_get_virq); + +#ifdef CONFIG_SYSFS +static struct attribute *msi_dev_attrs[] = { + NULL +}; + +static const struct attribute_group msi_irqs_group = { + .name = "msi_irqs", + .attrs = msi_dev_attrs, +}; + +static inline int msi_sysfs_create_group(struct device *dev) +{ + return devm_device_add_group(dev, &msi_irqs_group); +} + +static ssize_t msi_mode_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + /* MSI vs. MSIX is per device not per interrupt */ + bool is_msix = dev_is_pci(dev) ? to_pci_dev(dev)->msix_enabled : false; + + return sysfs_emit(buf, "%s\n", is_msix ? "msix" : "msi"); +} + +static void msi_sysfs_remove_desc(struct device *dev, struct msi_desc *desc) +{ + struct device_attribute *attrs = desc->sysfs_attrs; + int i; + + if (!attrs) + return; + + desc->sysfs_attrs = NULL; + for (i = 0; i < desc->nvec_used; i++) { + if (attrs[i].show) + sysfs_remove_file_from_group(&dev->kobj, &attrs[i].attr, msi_irqs_group.name); + kfree(attrs[i].attr.name); + } + kfree(attrs); +} + +static int msi_sysfs_populate_desc(struct device *dev, struct msi_desc *desc) +{ + struct device_attribute *attrs; + int ret, i; + + attrs = kcalloc(desc->nvec_used, sizeof(*attrs), GFP_KERNEL); + if (!attrs) + return -ENOMEM; + + desc->sysfs_attrs = attrs; + for (i = 0; i < desc->nvec_used; i++) { + sysfs_attr_init(&attrs[i].attr); + attrs[i].attr.name = kasprintf(GFP_KERNEL, "%d", desc->irq + i); + if (!attrs[i].attr.name) { + ret = -ENOMEM; + goto fail; + } + + attrs[i].attr.mode = 0444; + attrs[i].show = msi_mode_show; + + ret = sysfs_add_file_to_group(&dev->kobj, &attrs[i].attr, msi_irqs_group.name); + if (ret) { + attrs[i].show = NULL; + goto fail; + } + } + return 0; + +fail: + msi_sysfs_remove_desc(dev, desc); + return ret; +} + +#if defined(CONFIG_PCI_MSI_ARCH_FALLBACKS) || defined(CONFIG_PCI_XEN) +/** + * msi_device_populate_sysfs - Populate msi_irqs sysfs entries for a device + * @dev: The device (PCI, platform etc) which will get sysfs entries + */ +int msi_device_populate_sysfs(struct device *dev) +{ + struct msi_desc *desc; + int ret; + + msi_for_each_desc(desc, dev, MSI_DESC_ASSOCIATED) { + if (desc->sysfs_attrs) + continue; + ret = msi_sysfs_populate_desc(dev, desc); + if (ret) + return ret; + } + return 0; +} + +/** + * msi_device_destroy_sysfs - Destroy msi_irqs sysfs entries for a device + * @dev: The device (PCI, platform etc) for which to remove + * sysfs entries + */ +void msi_device_destroy_sysfs(struct device *dev) +{ + struct msi_desc *desc; + + msi_for_each_desc(desc, dev, MSI_DESC_ALL) + msi_sysfs_remove_desc(dev, desc); +} +#endif /* CONFIG_PCI_MSI_ARCH_FALLBACK || CONFIG_PCI_XEN */ +#else /* CONFIG_SYSFS */ +static inline int msi_sysfs_create_group(struct device *dev) { return 0; } +static inline int msi_sysfs_populate_desc(struct device *dev, struct msi_desc *desc) { return 0; } +static inline void msi_sysfs_remove_desc(struct device *dev, struct msi_desc *desc) { } +#endif /* !CONFIG_SYSFS */ + +#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); +} + +static void msi_check_level(struct irq_domain *domain, struct msi_msg *msg) +{ + struct msi_domain_info *info = domain->host_data; + + /* + * If the MSI provider has messed with the second message and + * not advertized that it is level-capable, signal the breakage. + */ + WARN_ON(!((info->flags & MSI_FLAG_LEVEL_CAPABLE) && + (info->chip->flags & IRQCHIP_SUPPORTS_LEVEL_MSI)) && + (msg[1].address_lo || msg[1].address_hi || msg[1].data)); +} + +/** + * 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. + * + * Return: IRQ_SET_MASK_* result code + */ +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[2] = { [1] = { }, }; + 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)); + msi_check_level(irq_data->domain, msg); + irq_chip_write_msi_msg(irq_data, msg); + } + + return ret; +} + +static int msi_domain_activate(struct irq_domain *domain, + struct irq_data *irq_data, bool early) +{ + struct msi_msg msg[2] = { [1] = { }, }; + + BUG_ON(irq_chip_compose_msi_msg(irq_data, msg)); + msi_check_level(irq_data->domain, msg); + irq_chip_write_msi_msg(irq_data, msg); + return 0; +} + +static void msi_domain_deactivate(struct irq_domain *domain, + struct irq_data *irq_data) +{ + struct msi_msg msg[2]; + + 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, +}; + +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; +} + +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, + .domain_alloc_irqs = __msi_domain_alloc_irqs, + .domain_free_irqs = __msi_domain_free_irqs, +}; + +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->domain_alloc_irqs == NULL) + ops->domain_alloc_irqs = msi_domain_ops_default.domain_alloc_irqs; + if (ops->domain_free_irqs == NULL) + ops->domain_free_irqs = msi_domain_ops_default.domain_free_irqs; + + if (!(info->flags & MSI_FLAG_USE_DEF_DOM_OPS)) + 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 an MSI interrupt domain + * @fwnode: Optional fwnode of the interrupt controller + * @info: MSI domain info + * @parent: Parent irq domain + * + * Return: pointer to the created &struct irq_domain or %NULL on failure + */ +struct irq_domain *msi_create_irq_domain(struct fwnode_handle *fwnode, + struct msi_domain_info *info, + struct irq_domain *parent) +{ + struct irq_domain *domain; + + msi_domain_update_dom_ops(info); + if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS) + msi_domain_update_chip_ops(info); + + domain = irq_domain_create_hierarchy(parent, IRQ_DOMAIN_FLAG_MSI, 0, + fwnode, &msi_domain_ops, info); + + if (domain && !domain->name && info->chip) + domain->name = info->chip->name; + + return domain; +} + +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_base, 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, virq; + + msi_lock_descs(dev); + ret = msi_add_simple_msi_descs(dev, virq_base, nvec); + if (ret) + goto unlock; + + for (virq = virq_base; virq < virq_base + nvec; virq++) { + desc = xa_load(&dev->msi.data->__store, virq); + desc->irq = virq; + + ops->set_desc(arg, desc); + ret = irq_domain_alloc_irqs_hierarchy(domain, virq, 1, arg); + if (ret) + goto fail; + + irq_set_msi_desc(virq, desc); + } + msi_unlock_descs(dev); + return 0; + +fail: + for (--virq; virq >= virq_base; virq--) + irq_domain_free_irqs_common(domain, virq, 1); + msi_free_msi_descs_range(dev, MSI_DESC_ALL, virq_base, virq_base + nvec - 1); +unlock: + msi_unlock_descs(dev); + return ret; +} + +/* + * Carefully check whether the device can use reservation mode. If + * reservation mode is enabled then the early activation will assign a + * dummy vector to the device. If the PCI/MSI device does not support + * masking of the entry then this can result in spurious interrupts when + * the device driver is not absolutely careful. But even then a malfunction + * of the hardware could result in a spurious interrupt on the dummy vector + * and render the device unusable. If the entry can be masked then the core + * logic will prevent the spurious interrupt and reservation mode can be + * used. For now reservation mode is restricted to PCI/MSI. + */ +static bool msi_check_reservation_mode(struct irq_domain *domain, + struct msi_domain_info *info, + struct device *dev) +{ + struct msi_desc *desc; + + switch(domain->bus_token) { + case DOMAIN_BUS_PCI_MSI: + case DOMAIN_BUS_VMD_MSI: + break; + default: + return false; + } + + if (!(info->flags & MSI_FLAG_MUST_REACTIVATE)) + return false; + + if (IS_ENABLED(CONFIG_PCI_MSI) && pci_msi_ignore_mask) + return false; + + /* + * Checking the first MSI descriptor is sufficient. MSIX supports + * masking and MSI does so when the can_mask attribute is set. + */ + desc = msi_first_desc(dev, MSI_DESC_ALL); + return desc->pci.msi_attrib.is_msix || desc->pci.msi_attrib.can_mask; +} + +static int msi_handle_pci_fail(struct irq_domain *domain, struct msi_desc *desc, + int allocated) +{ + switch(domain->bus_token) { + case DOMAIN_BUS_PCI_MSI: + case DOMAIN_BUS_VMD_MSI: + if (IS_ENABLED(CONFIG_PCI_MSI)) + break; + fallthrough; + default: + return -ENOSPC; + } + + /* Let a failed PCI multi MSI allocation retry */ + if (desc->nvec_used > 1) + return 1; + + /* If there was a successful allocation let the caller know */ + return allocated ? allocated : -ENOSPC; +} + +#define VIRQ_CAN_RESERVE 0x01 +#define VIRQ_ACTIVATE 0x02 + +static int msi_init_virq(struct irq_domain *domain, int virq, unsigned int vflags) +{ + struct irq_data *irqd = irq_domain_get_irq_data(domain, virq); + int ret; + + if (!(vflags & VIRQ_CAN_RESERVE)) { + irqd_clr_can_reserve(irqd); + + /* + * If the interrupt is managed but no CPU is available to + * service it, shut it down until better times. Note that + * we only do this on the !RESERVE path as x86 (the only + * architecture using this flag) deals with this in a + * different way by using a catch-all vector. + */ + if ((vflags & VIRQ_ACTIVATE) && + irqd_affinity_is_managed(irqd) && + !cpumask_intersects(irq_data_get_affinity_mask(irqd), + cpu_online_mask)) { + irqd_set_managed_shutdown(irqd); + return 0; + } + } + + if (!(vflags & VIRQ_ACTIVATE)) + return 0; + + ret = irq_domain_activate_irq(irqd, vflags & VIRQ_CAN_RESERVE); + if (ret) + return ret; + /* + * If the interrupt uses reservation mode, clear the activated bit + * so request_irq() will assign the final vector. + */ + if (vflags & VIRQ_CAN_RESERVE) + irqd_clr_activated(irqd); + return 0; +} + +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 = { }; + unsigned int vflags = 0; + struct msi_desc *desc; + int allocated = 0; + int i, ret, virq; + + ret = msi_domain_prepare_irqs(domain, dev, nvec, &arg); + if (ret) + return ret; + + /* + * 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) + vflags |= VIRQ_ACTIVATE; + + /* + * Interrupt can use a reserved vector and will not occupy + * a real device vector until the interrupt is requested. + */ + if (msi_check_reservation_mode(domain, info, dev)) + vflags |= VIRQ_CAN_RESERVE; + + msi_for_each_desc(desc, dev, MSI_DESC_NOTASSOCIATED) { + 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) + return msi_handle_pci_fail(domain, desc, allocated); + + for (i = 0; i < desc->nvec_used; i++) { + irq_set_msi_desc_off(virq, i, desc); + irq_debugfs_copy_devname(virq + i, dev); + ret = msi_init_virq(domain, virq + i, vflags); + if (ret) + return ret; + } + if (info->flags & MSI_FLAG_DEV_SYSFS) { + ret = msi_sysfs_populate_desc(dev, desc); + if (ret) + return ret; + } + allocated++; + } + return 0; +} + +static int msi_domain_add_simple_msi_descs(struct msi_domain_info *info, + struct device *dev, + unsigned int num_descs) +{ + if (!(info->flags & MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS)) + return 0; + + return msi_add_simple_msi_descs(dev, 0, num_descs); +} + +/** + * msi_domain_alloc_irqs_descs_locked - 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 + * + * Must be invoked from within a msi_lock_descs() / msi_unlock_descs() + * pair. Use this for MSI irqdomains which implement their own vector + * allocation/free. + * + * Return: %0 on success or an error code. + */ +int msi_domain_alloc_irqs_descs_locked(struct irq_domain *domain, struct device *dev, + int nvec) +{ + struct msi_domain_info *info = domain->host_data; + struct msi_domain_ops *ops = info->ops; + int ret; + + lockdep_assert_held(&dev->msi.data->mutex); + + ret = msi_domain_add_simple_msi_descs(info, dev, nvec); + if (ret) + return ret; + + ret = ops->domain_alloc_irqs(domain, dev, nvec); + if (ret) + msi_domain_free_irqs_descs_locked(domain, dev); + 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 + * + * Return: %0 on success or an error code. + */ +int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev, int nvec) +{ + int ret; + + msi_lock_descs(dev); + ret = msi_domain_alloc_irqs_descs_locked(domain, dev, nvec); + msi_unlock_descs(dev); + return ret; +} + +void __msi_domain_free_irqs(struct irq_domain *domain, struct device *dev) +{ + struct msi_domain_info *info = domain->host_data; + struct irq_data *irqd; + struct msi_desc *desc; + int i; + + /* Only handle MSI entries which have an interrupt associated */ + msi_for_each_desc(desc, dev, MSI_DESC_ASSOCIATED) { + /* Make sure all interrupts are deactivated */ + for (i = 0; i < desc->nvec_used; i++) { + irqd = irq_domain_get_irq_data(domain, desc->irq + i); + if (irqd && irqd_is_activated(irqd)) + irq_domain_deactivate_irq(irqd); + } + + irq_domain_free_irqs(desc->irq, desc->nvec_used); + if (info->flags & MSI_FLAG_DEV_SYSFS) + msi_sysfs_remove_desc(dev, desc); + desc->irq = 0; + } +} + +static void msi_domain_free_msi_descs(struct msi_domain_info *info, + struct device *dev) +{ + if (info->flags & MSI_FLAG_FREE_MSI_DESCS) + msi_free_msi_descs(dev); +} + +/** + * msi_domain_free_irqs_descs_locked - Free interrupts from a MSI interrupt @domain associated to @dev + * @domain: The domain to managing the interrupts + * @dev: Pointer to device struct of the device for which the interrupts + * are free + * + * Must be invoked from within a msi_lock_descs() / msi_unlock_descs() + * pair. Use this for MSI irqdomains which implement their own vector + * allocation. + */ +void msi_domain_free_irqs_descs_locked(struct irq_domain *domain, struct device *dev) +{ + struct msi_domain_info *info = domain->host_data; + struct msi_domain_ops *ops = info->ops; + + lockdep_assert_held(&dev->msi.data->mutex); + + ops->domain_free_irqs(domain, dev); + msi_domain_free_msi_descs(info, dev); +} + +/** + * msi_domain_free_irqs - Free interrupts from a MSI interrupt @domain associated to @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) +{ + msi_lock_descs(dev); + msi_domain_free_irqs_descs_locked(domain, dev); + msi_unlock_descs(dev); +} + +/** + * msi_get_domain_info - Get the MSI interrupt domain info for @domain + * @domain: The interrupt domain to retrieve data from + * + * Return: 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 */ |