diff options
Diffstat (limited to 'drivers/pci/msi.c')
| -rw-r--r-- | drivers/pci/msi.c | 1054 |
1 files changed, 0 insertions, 1054 deletions
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c deleted file mode 100644 index aca7578b05e5..000000000000 --- a/drivers/pci/msi.c +++ /dev/null @@ -1,1054 +0,0 @@ -/* - * File: msi.c - * Purpose: PCI Message Signaled Interrupt (MSI) - * - * Copyright (C) 2003-2004 Intel - * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com) - */ - -#include <linux/err.h> -#include <linux/mm.h> -#include <linux/irq.h> -#include <linux/interrupt.h> -#include <linux/init.h> -#include <linux/export.h> -#include <linux/ioport.h> -#include <linux/pci.h> -#include <linux/proc_fs.h> -#include <linux/msi.h> -#include <linux/smp.h> -#include <linux/errno.h> -#include <linux/io.h> -#include <linux/slab.h> - -#include "pci.h" - -static int pci_msi_enable = 1; - -#define msix_table_size(flags) ((flags & PCI_MSIX_FLAGS_QSIZE) + 1) - - -/* Arch hooks */ - -#ifndef arch_msi_check_device -int arch_msi_check_device(struct pci_dev *dev, int nvec, int type) -{ - return 0; -} -#endif - -#ifndef arch_setup_msi_irqs -# define arch_setup_msi_irqs default_setup_msi_irqs -# define HAVE_DEFAULT_MSI_SETUP_IRQS -#endif - -#ifdef HAVE_DEFAULT_MSI_SETUP_IRQS -int default_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) -{ - struct msi_desc *entry; - int ret; - - /* - * If an architecture wants to support multiple MSI, it needs to - * override arch_setup_msi_irqs() - */ - if (type == PCI_CAP_ID_MSI && nvec > 1) - return 1; - - list_for_each_entry(entry, &dev->msi_list, list) { - ret = arch_setup_msi_irq(dev, entry); - if (ret < 0) - return ret; - if (ret > 0) - return -ENOSPC; - } - - return 0; -} -#endif - -#ifndef arch_teardown_msi_irqs -# define arch_teardown_msi_irqs default_teardown_msi_irqs -# define HAVE_DEFAULT_MSI_TEARDOWN_IRQS -#endif - -#ifdef HAVE_DEFAULT_MSI_TEARDOWN_IRQS -void default_teardown_msi_irqs(struct pci_dev *dev) -{ - struct msi_desc *entry; - - list_for_each_entry(entry, &dev->msi_list, list) { - int i, nvec; - if (entry->irq == 0) - continue; - if (entry->nvec_used) - nvec = entry->nvec_used; - else - nvec = 1 << entry->msi_attrib.multiple; - for (i = 0; i < nvec; i++) - arch_teardown_msi_irq(entry->irq + i); - } -} -#endif - -#ifndef arch_restore_msi_irqs -# define arch_restore_msi_irqs default_restore_msi_irqs -# define HAVE_DEFAULT_MSI_RESTORE_IRQS -#endif - -#ifdef HAVE_DEFAULT_MSI_RESTORE_IRQS -void default_restore_msi_irqs(struct pci_dev *dev, int irq) -{ - struct msi_desc *entry; - - entry = NULL; - if (dev->msix_enabled) { - list_for_each_entry(entry, &dev->msi_list, list) { - if (irq == entry->irq) - break; - } - } else if (dev->msi_enabled) { - entry = irq_get_msi_desc(irq); - } - - if (entry) - write_msi_msg(irq, &entry->msg); -} -#endif - -static void msi_set_enable(struct pci_dev *dev, int enable) -{ - u16 control; - - pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control); - control &= ~PCI_MSI_FLAGS_ENABLE; - if (enable) - control |= PCI_MSI_FLAGS_ENABLE; - pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control); -} - -static void msix_set_enable(struct pci_dev *dev, int enable) -{ - u16 control; - - pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control); - control &= ~PCI_MSIX_FLAGS_ENABLE; - if (enable) - control |= PCI_MSIX_FLAGS_ENABLE; - pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control); -} - -static inline __attribute_const__ u32 msi_mask(unsigned x) -{ - /* Don't shift by >= width of type */ - if (x >= 5) - return 0xffffffff; - return (1 << (1 << x)) - 1; -} - -static inline __attribute_const__ u32 msi_capable_mask(u16 control) -{ - return msi_mask((control >> 1) & 7); -} - -static inline __attribute_const__ u32 msi_enabled_mask(u16 control) -{ - return msi_mask((control >> 4) & 7); -} - -/* - * PCI 2.3 does not specify mask bits for each MSI interrupt. Attempting to - * mask all MSI interrupts by clearing the MSI enable bit does not work - * reliably as devices without an INTx disable bit will then generate a - * level IRQ which will never be cleared. - */ -static u32 __msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) -{ - u32 mask_bits = desc->masked; - - if (!desc->msi_attrib.maskbit) - return 0; - - mask_bits &= ~mask; - mask_bits |= flag; - pci_write_config_dword(desc->dev, desc->mask_pos, mask_bits); - - return mask_bits; -} - -static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) -{ - desc->masked = __msi_mask_irq(desc, mask, flag); -} - -/* - * This internal function does not flush PCI writes to the device. - * All users must ensure that they read from the device before either - * assuming that the device state is up to date, or returning out of this - * file. This saves a few milliseconds when initialising devices with lots - * of MSI-X interrupts. - */ -static u32 __msix_mask_irq(struct msi_desc *desc, u32 flag) -{ - u32 mask_bits = desc->masked; - unsigned offset = desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE + - PCI_MSIX_ENTRY_VECTOR_CTRL; - mask_bits &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT; - if (flag) - mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT; - writel(mask_bits, desc->mask_base + offset); - - return mask_bits; -} - -static void msix_mask_irq(struct msi_desc *desc, u32 flag) -{ - desc->masked = __msix_mask_irq(desc, flag); -} - -#ifdef CONFIG_GENERIC_HARDIRQS - -static void msi_set_mask_bit(struct irq_data *data, u32 flag) -{ - struct msi_desc *desc = irq_data_get_msi(data); - - if (desc->msi_attrib.is_msix) { - msix_mask_irq(desc, flag); - readl(desc->mask_base); /* Flush write to device */ - } else { - unsigned offset = data->irq - desc->dev->irq; - msi_mask_irq(desc, 1 << offset, flag << offset); - } -} - -void mask_msi_irq(struct irq_data *data) -{ - msi_set_mask_bit(data, 1); -} - -void unmask_msi_irq(struct irq_data *data) -{ - msi_set_mask_bit(data, 0); -} - -#endif /* CONFIG_GENERIC_HARDIRQS */ - -void __read_msi_msg(struct msi_desc *entry, struct msi_msg *msg) -{ - BUG_ON(entry->dev->current_state != PCI_D0); - - if (entry->msi_attrib.is_msix) { - void __iomem *base = entry->mask_base + - entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE; - - msg->address_lo = readl(base + PCI_MSIX_ENTRY_LOWER_ADDR); - msg->address_hi = readl(base + PCI_MSIX_ENTRY_UPPER_ADDR); - msg->data = readl(base + PCI_MSIX_ENTRY_DATA); - } else { - struct pci_dev *dev = entry->dev; - int pos = dev->msi_cap; - u16 data; - - pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_LO, - &msg->address_lo); - if (entry->msi_attrib.is_64) { - pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_HI, - &msg->address_hi); - pci_read_config_word(dev, pos + PCI_MSI_DATA_64, &data); - } else { - msg->address_hi = 0; - pci_read_config_word(dev, pos + PCI_MSI_DATA_32, &data); - } - msg->data = data; - } -} - -void read_msi_msg(unsigned int irq, struct msi_msg *msg) -{ - struct msi_desc *entry = irq_get_msi_desc(irq); - - __read_msi_msg(entry, msg); -} - -void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg) -{ - /* Assert that the cache is valid, assuming that - * valid messages are not all-zeroes. */ - BUG_ON(!(entry->msg.address_hi | entry->msg.address_lo | - entry->msg.data)); - - *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); -} - -void __write_msi_msg(struct msi_desc *entry, struct msi_msg *msg) -{ - if (entry->dev->current_state != PCI_D0) { - /* Don't touch the hardware now */ - } else if (entry->msi_attrib.is_msix) { - void __iomem *base; - base = entry->mask_base + - entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE; - - writel(msg->address_lo, base + PCI_MSIX_ENTRY_LOWER_ADDR); - writel(msg->address_hi, base + PCI_MSIX_ENTRY_UPPER_ADDR); - writel(msg->data, base + PCI_MSIX_ENTRY_DATA); - } else { - struct pci_dev *dev = entry->dev; - int pos = dev->msi_cap; - u16 msgctl; - - pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &msgctl); - msgctl &= ~PCI_MSI_FLAGS_QSIZE; - msgctl |= entry->msi_attrib.multiple << 4; - pci_write_config_word(dev, pos + PCI_MSI_FLAGS, msgctl); - - pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_LO, - msg->address_lo); - if (entry->msi_attrib.is_64) { - pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_HI, - msg->address_hi); - pci_write_config_word(dev, pos + PCI_MSI_DATA_64, - msg->data); - } else { - pci_write_config_word(dev, pos + PCI_MSI_DATA_32, - msg->data); - } - } - entry->msg = *msg; -} - -void write_msi_msg(unsigned int irq, struct msi_msg *msg) -{ - struct msi_desc *entry = irq_get_msi_desc(irq); - - __write_msi_msg(entry, msg); -} - -static void free_msi_irqs(struct pci_dev *dev) -{ - struct msi_desc *entry, *tmp; - - list_for_each_entry(entry, &dev->msi_list, list) { - int i, nvec; - if (!entry->irq) - continue; - if (entry->nvec_used) - nvec = entry->nvec_used; - else - nvec = 1 << entry->msi_attrib.multiple; -#ifdef CONFIG_GENERIC_HARDIRQS - for (i = 0; i < nvec; i++) - BUG_ON(irq_has_action(entry->irq + i)); -#endif - } - - arch_teardown_msi_irqs(dev); - - list_for_each_entry_safe(entry, tmp, &dev->msi_list, list) { - if (entry->msi_attrib.is_msix) { - if (list_is_last(&entry->list, &dev->msi_list)) - iounmap(entry->mask_base); - } - - /* - * Its possible that we get into this path - * When populate_msi_sysfs fails, which means the entries - * were not registered with sysfs. In that case don't - * unregister them. - */ - if (entry->kobj.parent) { - kobject_del(&entry->kobj); - kobject_put(&entry->kobj); - } - - list_del(&entry->list); - kfree(entry); - } -} - -static struct msi_desc *alloc_msi_entry(struct pci_dev *dev) -{ - struct msi_desc *desc = kzalloc(sizeof(*desc), GFP_KERNEL); - if (!desc) - return NULL; - - INIT_LIST_HEAD(&desc->list); - desc->dev = dev; - - return desc; -} - -static void pci_intx_for_msi(struct pci_dev *dev, int enable) -{ - if (!(dev->dev_flags & PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG)) - pci_intx(dev, enable); -} - -static void __pci_restore_msi_state(struct pci_dev *dev) -{ - u16 control; - struct msi_desc *entry; - - if (!dev->msi_enabled) - return; - - entry = irq_get_msi_desc(dev->irq); - - pci_intx_for_msi(dev, 0); - msi_set_enable(dev, 0); - arch_restore_msi_irqs(dev, dev->irq); - - pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control); - msi_mask_irq(entry, msi_capable_mask(control), entry->masked); - control &= ~PCI_MSI_FLAGS_QSIZE; - control |= (entry->msi_attrib.multiple << 4) | PCI_MSI_FLAGS_ENABLE; - pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control); -} - -static void __pci_restore_msix_state(struct pci_dev *dev) -{ - struct msi_desc *entry; - u16 control; - - if (!dev->msix_enabled) - return; - BUG_ON(list_empty(&dev->msi_list)); - entry = list_first_entry(&dev->msi_list, struct msi_desc, list); - pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control); - - /* route the table */ - pci_intx_for_msi(dev, 0); - control |= PCI_MSIX_FLAGS_ENABLE | PCI_MSIX_FLAGS_MASKALL; - pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control); - - list_for_each_entry(entry, &dev->msi_list, list) { - arch_restore_msi_irqs(dev, entry->irq); - msix_mask_irq(entry, entry->masked); - } - - control &= ~PCI_MSIX_FLAGS_MASKALL; - pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control); -} - -void pci_restore_msi_state(struct pci_dev *dev) -{ - __pci_restore_msi_state(dev); - __pci_restore_msix_state(dev); -} -EXPORT_SYMBOL_GPL(pci_restore_msi_state); - - -#define to_msi_attr(obj) container_of(obj, struct msi_attribute, attr) -#define to_msi_desc(obj) container_of(obj, struct msi_desc, kobj) - -struct msi_attribute { - struct attribute attr; - ssize_t (*show)(struct msi_desc *entry, struct msi_attribute *attr, - char *buf); - ssize_t (*store)(struct msi_desc *entry, struct msi_attribute *attr, - const char *buf, size_t count); -}; - -static ssize_t show_msi_mode(struct msi_desc *entry, struct msi_attribute *atr, - char *buf) -{ - return sprintf(buf, "%s\n", entry->msi_attrib.is_msix ? "msix" : "msi"); -} - -static ssize_t msi_irq_attr_show(struct kobject *kobj, - struct attribute *attr, char *buf) -{ - struct msi_attribute *attribute = to_msi_attr(attr); - struct msi_desc *entry = to_msi_desc(kobj); - - if (!attribute->show) - return -EIO; - - return attribute->show(entry, attribute, buf); -} - -static const struct sysfs_ops msi_irq_sysfs_ops = { - .show = msi_irq_attr_show, -}; - -static struct msi_attribute mode_attribute = - __ATTR(mode, S_IRUGO, show_msi_mode, NULL); - - -static struct attribute *msi_irq_default_attrs[] = { - &mode_attribute.attr, - NULL -}; - -static void msi_kobj_release(struct kobject *kobj) -{ - struct msi_desc *entry = to_msi_desc(kobj); - - pci_dev_put(entry->dev); -} - -static struct kobj_type msi_irq_ktype = { - .release = msi_kobj_release, - .sysfs_ops = &msi_irq_sysfs_ops, - .default_attrs = msi_irq_default_attrs, -}; - -static int populate_msi_sysfs(struct pci_dev *pdev) -{ - struct msi_desc *entry; - struct kobject *kobj; - int ret; - int count = 0; - - pdev->msi_kset = kset_create_and_add("msi_irqs", NULL, &pdev->dev.kobj); - if (!pdev->msi_kset) - return -ENOMEM; - - list_for_each_entry(entry, &pdev->msi_list, list) { - kobj = &entry->kobj; - kobj->kset = pdev->msi_kset; - pci_dev_get(pdev); - ret = kobject_init_and_add(kobj, &msi_irq_ktype, NULL, - "%u", entry->irq); - if (ret) - goto out_unroll; - - count++; - } - - return 0; - -out_unroll: - list_for_each_entry(entry, &pdev->msi_list, list) { - if (!count) - break; - kobject_del(&entry->kobj); - kobject_put(&entry->kobj); - count--; - } - return ret; -} - -/** - * msi_capability_init - configure device's MSI capability structure - * @dev: pointer to the pci_dev data structure of MSI device function - * @nvec: number of interrupts to allocate - * - * Setup the MSI capability structure of the device with the requested - * number of interrupts. A return value of zero indicates the successful - * setup of an entry with the new MSI irq. A negative return value indicates - * an error, and a positive return value indicates the number of interrupts - * which could have been allocated. - */ -static int msi_capability_init(struct pci_dev *dev, int nvec) -{ - struct msi_desc *entry; - int ret; - u16 control; - unsigned mask; - - msi_set_enable(dev, 0); /* Disable MSI during set up */ - - pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control); - /* MSI Entry Initialization */ - entry = alloc_msi_entry(dev); - if (!entry) - return -ENOMEM; - - entry->msi_attrib.is_msix = 0; - entry->msi_attrib.is_64 = !!(control & PCI_MSI_FLAGS_64BIT); - entry->msi_attrib.entry_nr = 0; - entry->msi_attrib.maskbit = !!(control & PCI_MSI_FLAGS_MASKBIT); - entry->msi_attrib.default_irq = dev->irq; /* Save IOAPIC IRQ */ - entry->msi_attrib.pos = dev->msi_cap; - - if (control & PCI_MSI_FLAGS_64BIT) - entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_64; - else - entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_32; - /* All MSIs are unmasked by default, Mask them all */ - if (entry->msi_attrib.maskbit) - pci_read_config_dword(dev, entry->mask_pos, &entry->masked); - mask = msi_capable_mask(control); - msi_mask_irq(entry, mask, mask); - - list_add_tail(&entry->list, &dev->msi_list); - - /* Configure MSI capability structure */ - ret = arch_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSI); - if (ret) { - msi_mask_irq(entry, mask, ~mask); - free_msi_irqs(dev); - return ret; - } - - ret = populate_msi_sysfs(dev); - if (ret) { - msi_mask_irq(entry, mask, ~mask); - free_msi_irqs(dev); - return ret; - } - - /* Set MSI enabled bits */ - pci_intx_for_msi(dev, 0); - msi_set_enable(dev, 1); - dev->msi_enabled = 1; - - dev->irq = entry->irq; - return 0; -} - -static void __iomem *msix_map_region(struct pci_dev *dev, unsigned nr_entries) -{ - resource_size_t phys_addr; - u32 table_offset; - u8 bir; - - pci_read_config_dword(dev, dev->msix_cap + PCI_MSIX_TABLE, - &table_offset); - bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR); - table_offset &= PCI_MSIX_TABLE_OFFSET; - phys_addr = pci_resource_start(dev, bir) + table_offset; - - return ioremap_nocache(phys_addr, nr_entries * PCI_MSIX_ENTRY_SIZE); -} - -static int msix_setup_entries(struct pci_dev *dev, void __iomem *base, - struct msix_entry *entries, int nvec) -{ - struct msi_desc *entry; - int i; - - for (i = 0; i < nvec; i++) { - entry = alloc_msi_entry(dev); - if (!entry) { - if (!i) - iounmap(base); - else - free_msi_irqs(dev); - /* No enough memory. Don't try again */ - return -ENOMEM; - } - - entry->msi_attrib.is_msix = 1; - entry->msi_attrib.is_64 = 1; - entry->msi_attrib.entry_nr = entries[i].entry; - entry->msi_attrib.default_irq = dev->irq; - entry->msi_attrib.pos = dev->msix_cap; - entry->mask_base = base; - - list_add_tail(&entry->list, &dev->msi_list); - } - - return 0; -} - -static void msix_program_entries(struct pci_dev *dev, - struct msix_entry *entries) -{ - struct msi_desc *entry; - int i = 0; - - list_for_each_entry(entry, &dev->msi_list, list) { - int offset = entries[i].entry * PCI_MSIX_ENTRY_SIZE + - PCI_MSIX_ENTRY_VECTOR_CTRL; - - entries[i].vector = entry->irq; - irq_set_msi_desc(entry->irq, entry); - entry->masked = readl(entry->mask_base + offset); - msix_mask_irq(entry, 1); - i++; - } -} - -/** - * msix_capability_init - configure device's MSI-X capability - * @dev: pointer to the pci_dev data structure of MSI-X device function - * @entries: pointer to an array of struct msix_entry entries - * @nvec: number of @entries - * - * Setup the MSI-X capability structure of device function with a - * single MSI-X irq. A return of zero indicates the successful setup of - * requested MSI-X entries with allocated irqs or non-zero for otherwise. - **/ -static int msix_capability_init(struct pci_dev *dev, - struct msix_entry *entries, int nvec) -{ - int ret; - u16 control; - void __iomem *base; - - pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control); - - /* Ensure MSI-X is disabled while it is set up */ - control &= ~PCI_MSIX_FLAGS_ENABLE; - pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control); - - /* Request & Map MSI-X table region */ - base = msix_map_region(dev, msix_table_size(control)); - if (!base) - return -ENOMEM; - - ret = msix_setup_entries(dev, base, entries, nvec); - if (ret) - return ret; - - ret = arch_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX); - if (ret) - goto error; - - /* - * Some devices require MSI-X to be enabled before we can touch the - * MSI-X registers. We need to mask all the vectors to prevent - * interrupts coming in before they're fully set up. - */ - control |= PCI_MSIX_FLAGS_MASKALL | PCI_MSIX_FLAGS_ENABLE; - pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control); - - msix_program_entries(dev, entries); - - ret = populate_msi_sysfs(dev); - if (ret) { - ret = 0; - goto error; - } - - /* Set MSI-X enabled bits and unmask the function */ - pci_intx_for_msi(dev, 0); - dev->msix_enabled = 1; - - control &= ~PCI_MSIX_FLAGS_MASKALL; - pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control); - - return 0; - -error: - if (ret < 0) { - /* - * If we had some success, report the number of irqs - * we succeeded in setting up. - */ - struct msi_desc *entry; - int avail = 0; - - list_for_each_entry(entry, &dev->msi_list, list) { - if (entry->irq != 0) - avail++; - } - if (avail != 0) - ret = avail; - } - - free_msi_irqs(dev); - - return ret; -} - -/** - * pci_msi_check_device - check whether MSI may be enabled on a device - * @dev: pointer to the pci_dev data structure of MSI device function - * @nvec: how many MSIs have been requested ? - * @type: are we checking for MSI or MSI-X ? - * - * Look at global flags, the device itself, and its parent busses - * to determine if MSI/-X are supported for the device. If MSI/-X is - * supported return 0, else return an error code. - **/ -static int pci_msi_check_device(struct pci_dev *dev, int nvec, int type) -{ - struct pci_bus *bus; - int ret; - - /* MSI must be globally enabled and supported by the device */ - if (!pci_msi_enable || !dev || dev->no_msi) - return -EINVAL; - - /* - * You can't ask to have 0 or less MSIs configured. - * a) it's stupid .. - * b) the list manipulation code assumes nvec >= 1. - */ - if (nvec < 1) - return -ERANGE; - - /* - * Any bridge which does NOT route MSI transactions from its - * secondary bus to its primary bus must set NO_MSI flag on - * the secondary pci_bus. - * We expect only arch-specific PCI host bus controller driver - * or quirks for specific PCI bridges to be setting NO_MSI. - */ - for (bus = dev->bus; bus; bus = bus->parent) - if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI) - return -EINVAL; - - ret = arch_msi_check_device(dev, nvec, type); - if (ret) - return ret; - - return 0; -} - -/** - * pci_enable_msi_block - configure device's MSI capability structure - * @dev: device to configure - * @nvec: number of interrupts to configure - * - * Allocate IRQs for a device with the MSI capability. - * This function returns a negative errno if an error occurs. If it - * is unable to allocate the number of interrupts requested, it returns - * the number of interrupts it might be able to allocate. If it successfully - * allocates at least the number of interrupts requested, it returns 0 and - * updates the @dev's irq member to the lowest new interrupt number; the - * other interrupt numbers allocated to this device are consecutive. - */ -int pci_enable_msi_block(struct pci_dev *dev, unsigned int nvec) -{ - int status, maxvec; - u16 msgctl; - - if (!dev->msi_cap) - return -EINVAL; - - pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &msgctl); - maxvec = 1 << ((msgctl & PCI_MSI_FLAGS_QMASK) >> 1); - if (nvec > maxvec) - return maxvec; - - status = pci_msi_check_device(dev, nvec, PCI_CAP_ID_MSI); - if (status) - return status; - - WARN_ON(!!dev->msi_enabled); - - /* Check whether driver already requested MSI-X irqs */ - if (dev->msix_enabled) { - dev_info(&dev->dev, "can't enable MSI " - "(MSI-X already enabled)\n"); - return -EINVAL; - } - - status = msi_capability_init(dev, nvec); - return status; -} -EXPORT_SYMBOL(pci_enable_msi_block); - -int pci_enable_msi_block_auto(struct pci_dev *dev, unsigned int *maxvec) -{ - int ret, nvec; - u16 msgctl; - - if (!dev->msi_cap) - return -EINVAL; - - pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &msgctl); - ret = 1 << ((msgctl & PCI_MSI_FLAGS_QMASK) >> 1); - - if (maxvec) - *maxvec = ret; - - do { - nvec = ret; - ret = pci_enable_msi_block(dev, nvec); - } while (ret > 0); - - if (ret < 0) - return ret; - return nvec; -} -EXPORT_SYMBOL(pci_enable_msi_block_auto); - -void pci_msi_shutdown(struct pci_dev *dev) -{ - struct msi_desc *desc; - u32 mask; - u16 ctrl; - - if (!pci_msi_enable || !dev || !dev->msi_enabled) - return; - - BUG_ON(list_empty(&dev->msi_list)); - desc = list_first_entry(&dev->msi_list, struct msi_desc, list); - - msi_set_enable(dev, 0); - pci_intx_for_msi(dev, 1); - dev->msi_enabled = 0; - - /* Return the device with MSI unmasked as initial states */ - pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &ctrl); - mask = msi_capable_mask(ctrl); - /* Keep cached state to be restored */ - __msi_mask_irq(desc, mask, ~mask); - - /* Restore dev->irq to its default pin-assertion irq */ - dev->irq = desc->msi_attrib.default_irq; -} - -void pci_disable_msi(struct pci_dev *dev) -{ - if (!pci_msi_enable || !dev || !dev->msi_enabled) - return; - - pci_msi_shutdown(dev); - free_msi_irqs(dev); - kset_unregister(dev->msi_kset); - dev->msi_kset = NULL; -} -EXPORT_SYMBOL(pci_disable_msi); - -/** - * pci_msix_table_size - return the number of device's MSI-X table entries - * @dev: pointer to the pci_dev data structure of MSI-X device function - */ -int pci_msix_table_size(struct pci_dev *dev) -{ - u16 control; - - if (!dev->msix_cap) - return 0; - - pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control); - return msix_table_size(control); -} - -/** - * pci_enable_msix - configure device's MSI-X capability structure - * @dev: pointer to the pci_dev data structure of MSI-X device function - * @entries: pointer to an array of MSI-X entries - * @nvec: number of MSI-X irqs requested for allocation by device driver - * - * Setup the MSI-X capability structure of device function with the number - * of requested irqs upon its software driver call to request for - * MSI-X mode enabled on its hardware device function. A return of zero - * indicates the successful configuration of MSI-X capability structure - * with new allocated MSI-X irqs. A return of < 0 indicates a failure. - * Or a return of > 0 indicates that driver request is exceeding the number - * of irqs or MSI-X vectors available. Driver should use the returned value to - * re-send its request. - **/ -int pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, int nvec) -{ - int status, nr_entries; - int i, j; - - if (!entries || !dev->msix_cap) - return -EINVAL; - - status = pci_msi_check_device(dev, nvec, PCI_CAP_ID_MSIX); - if (status) - return status; - - nr_entries = pci_msix_table_size(dev); - if (nvec > nr_entries) - return nr_entries; - - /* Check for any invalid entries */ - for (i = 0; i < nvec; i++) { - if (entries[i].entry >= nr_entries) - return -EINVAL; /* invalid entry */ - for (j = i + 1; j < nvec; j++) { - if (entries[i].entry == entries[j].entry) - return -EINVAL; /* duplicate entry */ - } - } - WARN_ON(!!dev->msix_enabled); - - /* Check whether driver already requested for MSI irq */ - if (dev->msi_enabled) { - dev_info(&dev->dev, "can't enable MSI-X " - "(MSI IRQ already assigned)\n"); - return -EINVAL; - } - status = msix_capability_init(dev, entries, nvec); - return status; -} -EXPORT_SYMBOL(pci_enable_msix); - -void pci_msix_shutdown(struct pci_dev *dev) -{ - struct msi_desc *entry; - - if (!pci_msi_enable || !dev || !dev->msix_enabled) - return; - - /* Return the device with MSI-X masked as initial states */ - list_for_each_entry(entry, &dev->msi_list, list) { - /* Keep cached states to be restored */ - __msix_mask_irq(entry, 1); - } - - msix_set_enable(dev, 0); - pci_intx_for_msi(dev, 1); - dev->msix_enabled = 0; -} - -void pci_disable_msix(struct pci_dev *dev) -{ - if (!pci_msi_enable || !dev || !dev->msix_enabled) - return; - - pci_msix_shutdown(dev); - free_msi_irqs(dev); - kset_unregister(dev->msi_kset); - dev->msi_kset = NULL; -} -EXPORT_SYMBOL(pci_disable_msix); - -/** - * msi_remove_pci_irq_vectors - reclaim MSI(X) irqs to unused state - * @dev: pointer to the pci_dev data structure of MSI(X) device function - * - * Being called during hotplug remove, from which the device function - * is hot-removed. All previous assigned MSI/MSI-X irqs, if - * allocated for this device function, are reclaimed to unused state, - * which may be used later on. - **/ -void msi_remove_pci_irq_vectors(struct pci_dev *dev) -{ - if (!pci_msi_enable || !dev) - return; - - if (dev->msi_enabled || dev->msix_enabled) - free_msi_irqs(dev); -} - -void pci_no_msi(void) -{ - pci_msi_enable = 0; -} - -/** - * pci_msi_enabled - is MSI enabled? - * - * Returns true if MSI has not been disabled by the command-line option - * pci=nomsi. - **/ -int pci_msi_enabled(void) -{ - return pci_msi_enable; -} -EXPORT_SYMBOL(pci_msi_enabled); - -void pci_msi_init_pci_dev(struct pci_dev *dev) -{ - INIT_LIST_HEAD(&dev->msi_list); - - /* Disable the msi hardware to avoid screaming interrupts - * during boot. This is the power on reset default so - * usually this should be a noop. - */ - dev->msi_cap = pci_find_capability(dev, PCI_CAP_ID_MSI); - if (dev->msi_cap) - msi_set_enable(dev, 0); - - dev->msix_cap = pci_find_capability(dev, PCI_CAP_ID_MSIX); - if (dev->msix_cap) - msix_set_enable(dev, 0); -} |