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path: root/drivers/pci/msi.c
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-rw-r--r--drivers/pci/msi.c1365
1 files changed, 1365 insertions, 0 deletions
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
new file mode 100644
index 000000000..c3e7dfcf9
--- /dev/null
+++ b/drivers/pci/msi.c
@@ -0,0 +1,1365 @@
+/*
+ * 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/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 <linux/irqdomain.h>
+
+#include "pci.h"
+
+static int pci_msi_enable = 1;
+int pci_msi_ignore_mask;
+
+#define msix_table_size(flags) ((flags & PCI_MSIX_FLAGS_QSIZE) + 1)
+
+#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
+static struct irq_domain *pci_msi_default_domain;
+static DEFINE_MUTEX(pci_msi_domain_lock);
+
+struct irq_domain * __weak arch_get_pci_msi_domain(struct pci_dev *dev)
+{
+ return pci_msi_default_domain;
+}
+
+static struct irq_domain *pci_msi_get_domain(struct pci_dev *dev)
+{
+ struct irq_domain *domain = NULL;
+
+ if (dev->bus->msi)
+ domain = dev->bus->msi->domain;
+ if (!domain)
+ domain = arch_get_pci_msi_domain(dev);
+
+ return domain;
+}
+
+static int pci_msi_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+{
+ struct irq_domain *domain;
+
+ domain = pci_msi_get_domain(dev);
+ if (domain)
+ return pci_msi_domain_alloc_irqs(domain, dev, nvec, type);
+
+ return arch_setup_msi_irqs(dev, nvec, type);
+}
+
+static void pci_msi_teardown_msi_irqs(struct pci_dev *dev)
+{
+ struct irq_domain *domain;
+
+ domain = pci_msi_get_domain(dev);
+ if (domain)
+ pci_msi_domain_free_irqs(domain, dev);
+ else
+ arch_teardown_msi_irqs(dev);
+}
+#else
+#define pci_msi_setup_msi_irqs arch_setup_msi_irqs
+#define pci_msi_teardown_msi_irqs arch_teardown_msi_irqs
+#endif
+
+/* Arch hooks */
+
+struct msi_controller * __weak pcibios_msi_controller(struct pci_dev *dev)
+{
+ return NULL;
+}
+
+static struct msi_controller *pci_msi_controller(struct pci_dev *dev)
+{
+ struct msi_controller *msi_ctrl = dev->bus->msi;
+
+ if (msi_ctrl)
+ return msi_ctrl;
+
+ return pcibios_msi_controller(dev);
+}
+
+int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
+{
+ struct msi_controller *chip = pci_msi_controller(dev);
+ int err;
+
+ if (!chip || !chip->setup_irq)
+ return -EINVAL;
+
+ err = chip->setup_irq(chip, dev, desc);
+ if (err < 0)
+ return err;
+
+ irq_set_chip_data(desc->irq, chip);
+
+ return 0;
+}
+
+void __weak arch_teardown_msi_irq(unsigned int irq)
+{
+ struct msi_controller *chip = irq_get_chip_data(irq);
+
+ if (!chip || !chip->teardown_irq)
+ return;
+
+ chip->teardown_irq(chip, irq);
+}
+
+int __weak arch_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;
+}
+
+/*
+ * We have a default implementation available as a separate non-weak
+ * function, as it is used by the Xen x86 PCI code
+ */
+void default_teardown_msi_irqs(struct pci_dev *dev)
+{
+ int i;
+ struct msi_desc *entry;
+
+ list_for_each_entry(entry, &dev->msi_list, list)
+ if (entry->irq)
+ for (i = 0; i < entry->nvec_used; i++)
+ arch_teardown_msi_irq(entry->irq + i);
+}
+
+void __weak arch_teardown_msi_irqs(struct pci_dev *dev)
+{
+ return default_teardown_msi_irqs(dev);
+}
+
+static void default_restore_msi_irq(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)
+ __pci_write_msi_msg(entry, &entry->msg);
+}
+
+void __weak arch_restore_msi_irqs(struct pci_dev *dev)
+{
+ return default_restore_msi_irqs(dev);
+}
+
+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_clear_and_set_ctrl(struct pci_dev *dev, u16 clear, u16 set)
+{
+ u16 ctrl;
+
+ pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &ctrl);
+ ctrl &= ~clear;
+ ctrl |= set;
+ pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, ctrl);
+}
+
+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;
+}
+
+/*
+ * 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.
+ */
+u32 __pci_msi_desc_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
+{
+ u32 mask_bits = desc->masked;
+
+ if (pci_msi_ignore_mask || !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 = __pci_msi_desc_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.
+ */
+u32 __pci_msix_desc_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;
+
+ if (pci_msi_ignore_mask)
+ return 0;
+
+ 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 = __pci_msix_desc_mask_irq(desc, flag);
+}
+
+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->irq;
+ msi_mask_irq(desc, 1 << offset, flag << offset);
+ }
+}
+
+/**
+ * pci_msi_mask_irq - Generic irq chip callback to mask PCI/MSI interrupts
+ * @data: pointer to irqdata associated to that interrupt
+ */
+void pci_msi_mask_irq(struct irq_data *data)
+{
+ msi_set_mask_bit(data, 1);
+}
+
+/**
+ * pci_msi_unmask_irq - Generic irq chip callback to unmask PCI/MSI interrupts
+ * @data: pointer to irqdata associated to that interrupt
+ */
+void pci_msi_unmask_irq(struct irq_data *data)
+{
+ msi_set_mask_bit(data, 0);
+}
+
+void default_restore_msi_irqs(struct pci_dev *dev)
+{
+ struct msi_desc *entry;
+
+ list_for_each_entry(entry, &dev->msi_list, list)
+ default_restore_msi_irq(dev, entry->irq);
+}
+
+void __pci_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 __pci_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 pci_write_msi_msg(unsigned int irq, struct msi_msg *msg)
+{
+ struct msi_desc *entry = irq_get_msi_desc(irq);
+
+ __pci_write_msi_msg(entry, msg);
+}
+EXPORT_SYMBOL_GPL(pci_write_msi_msg);
+
+static void free_msi_irqs(struct pci_dev *dev)
+{
+ struct msi_desc *entry, *tmp;
+ struct attribute **msi_attrs;
+ struct device_attribute *dev_attr;
+ int i, count = 0;
+
+ list_for_each_entry(entry, &dev->msi_list, list)
+ if (entry->irq)
+ for (i = 0; i < entry->nvec_used; i++)
+ BUG_ON(irq_has_action(entry->irq + i));
+
+ pci_msi_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);
+ }
+
+ list_del(&entry->list);
+ kfree(entry);
+ }
+
+ if (dev->msi_irq_groups) {
+ sysfs_remove_groups(&dev->dev.kobj, dev->msi_irq_groups);
+ msi_attrs = dev->msi_irq_groups[0]->attrs;
+ while (msi_attrs[count]) {
+ dev_attr = container_of(msi_attrs[count],
+ struct device_attribute, attr);
+ kfree(dev_attr->attr.name);
+ kfree(dev_attr);
+ ++count;
+ }
+ kfree(msi_attrs);
+ kfree(dev->msi_irq_groups[0]);
+ kfree(dev->msi_irq_groups);
+ dev->msi_irq_groups = NULL;
+ }
+}
+
+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);
+
+ pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
+ msi_mask_irq(entry, msi_mask(entry->msi_attrib.multi_cap),
+ 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;
+
+ if (!dev->msix_enabled)
+ return;
+ BUG_ON(list_empty(&dev->msi_list));
+
+ /* route the table */
+ pci_intx_for_msi(dev, 0);
+ msix_clear_and_set_ctrl(dev, 0,
+ PCI_MSIX_FLAGS_ENABLE | PCI_MSIX_FLAGS_MASKALL);
+
+ arch_restore_msi_irqs(dev);
+ list_for_each_entry(entry, &dev->msi_list, list)
+ msix_mask_irq(entry, entry->masked);
+
+ msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0);
+}
+
+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);
+
+static ssize_t msi_mode_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct msi_desc *entry;
+ unsigned long irq;
+ int retval;
+
+ retval = kstrtoul(attr->attr.name, 10, &irq);
+ if (retval)
+ return retval;
+
+ entry = irq_get_msi_desc(irq);
+ if (entry)
+ return sprintf(buf, "%s\n",
+ entry->msi_attrib.is_msix ? "msix" : "msi");
+
+ return -ENODEV;
+}
+
+static int populate_msi_sysfs(struct pci_dev *pdev)
+{
+ struct attribute **msi_attrs;
+ struct attribute *msi_attr;
+ struct device_attribute *msi_dev_attr;
+ struct attribute_group *msi_irq_group;
+ const struct attribute_group **msi_irq_groups;
+ struct msi_desc *entry;
+ int ret = -ENOMEM;
+ int num_msi = 0;
+ int count = 0;
+
+ /* Determine how many msi entries we have */
+ list_for_each_entry(entry, &pdev->msi_list, list)
+ ++num_msi;
+ if (!num_msi)
+ return 0;
+
+ /* Dynamically create the MSI attributes for the PCI device */
+ msi_attrs = kzalloc(sizeof(void *) * (num_msi + 1), GFP_KERNEL);
+ if (!msi_attrs)
+ return -ENOMEM;
+ list_for_each_entry(entry, &pdev->msi_list, list) {
+ msi_dev_attr = kzalloc(sizeof(*msi_dev_attr), GFP_KERNEL);
+ if (!msi_dev_attr)
+ goto error_attrs;
+ msi_attrs[count] = &msi_dev_attr->attr;
+
+ sysfs_attr_init(&msi_dev_attr->attr);
+ msi_dev_attr->attr.name = kasprintf(GFP_KERNEL, "%d",
+ entry->irq);
+ if (!msi_dev_attr->attr.name)
+ goto error_attrs;
+ msi_dev_attr->attr.mode = S_IRUGO;
+ msi_dev_attr->show = msi_mode_show;
+ ++count;
+ }
+
+ msi_irq_group = kzalloc(sizeof(*msi_irq_group), GFP_KERNEL);
+ if (!msi_irq_group)
+ goto error_attrs;
+ msi_irq_group->name = "msi_irqs";
+ msi_irq_group->attrs = msi_attrs;
+
+ msi_irq_groups = kzalloc(sizeof(void *) * 2, GFP_KERNEL);
+ if (!msi_irq_groups)
+ goto error_irq_group;
+ msi_irq_groups[0] = msi_irq_group;
+
+ ret = sysfs_create_groups(&pdev->dev.kobj, msi_irq_groups);
+ if (ret)
+ goto error_irq_groups;
+ pdev->msi_irq_groups = msi_irq_groups;
+
+ return 0;
+
+error_irq_groups:
+ kfree(msi_irq_groups);
+error_irq_group:
+ kfree(msi_irq_group);
+error_attrs:
+ count = 0;
+ msi_attr = msi_attrs[count];
+ while (msi_attr) {
+ msi_dev_attr = container_of(msi_attr, struct device_attribute, attr);
+ kfree(msi_attr->name);
+ kfree(msi_dev_attr);
+ ++count;
+ msi_attr = msi_attrs[count];
+ }
+ kfree(msi_attrs);
+ return ret;
+}
+
+static struct msi_desc *msi_setup_entry(struct pci_dev *dev, int nvec)
+{
+ u16 control;
+ struct msi_desc *entry;
+
+ /* MSI Entry Initialization */
+ entry = alloc_msi_entry(dev);
+ if (!entry)
+ return NULL;
+
+ pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
+
+ 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.multi_cap = (control & PCI_MSI_FLAGS_QMASK) >> 1;
+ entry->msi_attrib.multiple = ilog2(__roundup_pow_of_two(nvec));
+ entry->nvec_used = nvec;
+
+ 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;
+
+ /* Save the initial mask status */
+ if (entry->msi_attrib.maskbit)
+ pci_read_config_dword(dev, entry->mask_pos, &entry->masked);
+
+ return entry;
+}
+
+static int msi_verify_entries(struct pci_dev *dev)
+{
+ struct msi_desc *entry;
+
+ list_for_each_entry(entry, &dev->msi_list, list) {
+ if (!dev->no_64bit_msi || !entry->msg.address_hi)
+ continue;
+ dev_err(&dev->dev, "Device has broken 64-bit MSI but arch"
+ " tried to assign one above 4G\n");
+ return -EIO;
+ }
+ return 0;
+}
+
+/**
+ * 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;
+ unsigned mask;
+
+ msi_set_enable(dev, 0); /* Disable MSI during set up */
+
+ entry = msi_setup_entry(dev, nvec);
+ if (!entry)
+ return -ENOMEM;
+
+ /* All MSIs are unmasked by default, Mask them all */
+ mask = msi_mask(entry->msi_attrib.multi_cap);
+ msi_mask_irq(entry, mask, mask);
+
+ list_add_tail(&entry->list, &dev->msi_list);
+
+ /* Configure MSI capability structure */
+ ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSI);
+ if (ret) {
+ msi_mask_irq(entry, mask, ~mask);
+ free_msi_irqs(dev);
+ return ret;
+ }
+
+ ret = msi_verify_entries(dev);
+ 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;
+ unsigned long flags;
+ u8 bir;
+
+ pci_read_config_dword(dev, dev->msix_cap + PCI_MSIX_TABLE,
+ &table_offset);
+ bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR);
+ flags = pci_resource_flags(dev, bir);
+ if (!flags || (flags & IORESOURCE_UNSET))
+ return NULL;
+
+ 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->mask_base = base;
+ entry->nvec_used = 1;
+
+ 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;
+ 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;
+
+ /* Ensure MSI-X is disabled while it is set up */
+ msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
+
+ pci_read_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 = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX);
+ if (ret)
+ goto out_avail;
+
+ /* Check if all MSI entries honor device restrictions */
+ ret = msi_verify_entries(dev);
+ if (ret)
+ goto out_free;
+
+ /*
+ * 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.
+ */
+ msix_clear_and_set_ctrl(dev, 0,
+ PCI_MSIX_FLAGS_MASKALL | PCI_MSIX_FLAGS_ENABLE);
+
+ msix_program_entries(dev, entries);
+
+ ret = populate_msi_sysfs(dev);
+ if (ret)
+ goto out_free;
+
+ /* Set MSI-X enabled bits and unmask the function */
+ pci_intx_for_msi(dev, 0);
+ dev->msix_enabled = 1;
+
+ msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0);
+
+ return 0;
+
+out_avail:
+ 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;
+ }
+
+out_free:
+ free_msi_irqs(dev);
+
+ return ret;
+}
+
+/**
+ * pci_msi_supported - 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 ?
+ *
+ * Look at global flags, the device itself, and its parent buses
+ * to determine if MSI/-X are supported for the device. If MSI/-X is
+ * supported return 1, else return 0.
+ **/
+static int pci_msi_supported(struct pci_dev *dev, int nvec)
+{
+ struct pci_bus *bus;
+
+ /* MSI must be globally enabled and supported by the device */
+ if (!pci_msi_enable)
+ return 0;
+
+ if (!dev || dev->no_msi || dev->current_state != PCI_D0)
+ return 0;
+
+ /*
+ * 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 0;
+
+ /*
+ * 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 0;
+
+ return 1;
+}
+
+/**
+ * pci_msi_vec_count - Return the number of MSI vectors a device can send
+ * @dev: device to report about
+ *
+ * This function returns the number of MSI vectors a device requested via
+ * Multiple Message Capable register. It returns a negative errno if the
+ * device is not capable sending MSI interrupts. Otherwise, the call succeeds
+ * and returns a power of two, up to a maximum of 2^5 (32), according to the
+ * MSI specification.
+ **/
+int pci_msi_vec_count(struct pci_dev *dev)
+{
+ int ret;
+ 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);
+
+ return ret;
+}
+EXPORT_SYMBOL(pci_msi_vec_count);
+
+void pci_msi_shutdown(struct pci_dev *dev)
+{
+ struct msi_desc *desc;
+ u32 mask;
+
+ 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 */
+ mask = msi_mask(desc->msi_attrib.multi_cap);
+ /* Keep cached state to be restored */
+ __pci_msi_desc_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);
+}
+EXPORT_SYMBOL(pci_disable_msi);
+
+/**
+ * pci_msix_vec_count - return the number of device's MSI-X table entries
+ * @dev: pointer to the pci_dev data structure of MSI-X device function
+ * This function returns the number of device's MSI-X table entries and
+ * therefore the number of MSI-X vectors device is capable of sending.
+ * It returns a negative errno if the device is not capable of sending MSI-X
+ * interrupts.
+ **/
+int pci_msix_vec_count(struct pci_dev *dev)
+{
+ u16 control;
+
+ if (!dev->msix_cap)
+ return -EINVAL;
+
+ pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control);
+ return msix_table_size(control);
+}
+EXPORT_SYMBOL(pci_msix_vec_count);
+
+/**
+ * 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 nr_entries;
+ int i, j;
+
+ if (!pci_msi_supported(dev, nvec))
+ return -EINVAL;
+
+ if (!entries)
+ return -EINVAL;
+
+ nr_entries = pci_msix_vec_count(dev);
+ if (nr_entries < 0)
+ return nr_entries;
+ 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;
+ }
+ return msix_capability_init(dev, entries, nvec);
+}
+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 */
+ __pci_msix_desc_mask_irq(entry, 1);
+ }
+
+ msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 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);
+}
+EXPORT_SYMBOL(pci_disable_msix);
+
+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_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
+}
+
+/**
+ * pci_enable_msi_range - configure device's MSI capability structure
+ * @dev: device to configure
+ * @minvec: minimal number of interrupts to configure
+ * @maxvec: maximum number of interrupts to configure
+ *
+ * This function tries to allocate a maximum possible number of interrupts in a
+ * range between @minvec and @maxvec. It returns a negative errno if an error
+ * occurs. If it succeeds, it returns the actual number of interrupts allocated
+ * 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_range(struct pci_dev *dev, int minvec, int maxvec)
+{
+ int nvec;
+ int rc;
+
+ if (!pci_msi_supported(dev, minvec))
+ return -EINVAL;
+
+ 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;
+ }
+
+ if (maxvec < minvec)
+ return -ERANGE;
+
+ nvec = pci_msi_vec_count(dev);
+ if (nvec < 0)
+ return nvec;
+ else if (nvec < minvec)
+ return -EINVAL;
+ else if (nvec > maxvec)
+ nvec = maxvec;
+
+ do {
+ rc = msi_capability_init(dev, nvec);
+ if (rc < 0) {
+ return rc;
+ } else if (rc > 0) {
+ if (rc < minvec)
+ return -ENOSPC;
+ nvec = rc;
+ }
+ } while (rc);
+
+ return nvec;
+}
+EXPORT_SYMBOL(pci_enable_msi_range);
+
+/**
+ * pci_enable_msix_range - 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
+ * @minvec: minimum number of MSI-X irqs requested
+ * @maxvec: maximum number of MSI-X irqs requested
+ *
+ * Setup the MSI-X capability structure of device function with a maximum
+ * possible number of interrupts in the range between @minvec and @maxvec
+ * upon its software driver call to request for MSI-X mode enabled on its
+ * hardware device function. It returns a negative errno if an error occurs.
+ * If it succeeds, it returns the actual number of interrupts allocated and
+ * indicates the successful configuration of MSI-X capability structure
+ * with new allocated MSI-X interrupts.
+ **/
+int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries,
+ int minvec, int maxvec)
+{
+ int nvec = maxvec;
+ int rc;
+
+ if (maxvec < minvec)
+ return -ERANGE;
+
+ do {
+ rc = pci_enable_msix(dev, entries, nvec);
+ if (rc < 0) {
+ return rc;
+ } else if (rc > 0) {
+ if (rc < minvec)
+ return -ENOSPC;
+ nvec = rc;
+ }
+ } while (rc);
+
+ return nvec;
+}
+EXPORT_SYMBOL(pci_enable_msix_range);
+
+#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
+/**
+ * pci_msi_domain_write_msg - Helper to write MSI message to PCI config space
+ * @irq_data: Pointer to interrupt data of the MSI interrupt
+ * @msg: Pointer to the message
+ */
+void pci_msi_domain_write_msg(struct irq_data *irq_data, struct msi_msg *msg)
+{
+ struct msi_desc *desc = irq_data->msi_desc;
+
+ /*
+ * For MSI-X desc->irq is always equal to irq_data->irq. For
+ * MSI only the first interrupt of MULTI MSI passes the test.
+ */
+ if (desc->irq == irq_data->irq)
+ __pci_write_msi_msg(desc, msg);
+}
+
+/**
+ * pci_msi_domain_calc_hwirq - Generate a unique ID for an MSI source
+ * @dev: Pointer to the PCI device
+ * @desc: Pointer to the msi descriptor
+ *
+ * The ID number is only used within the irqdomain.
+ */
+irq_hw_number_t pci_msi_domain_calc_hwirq(struct pci_dev *dev,
+ struct msi_desc *desc)
+{
+ return (irq_hw_number_t)desc->msi_attrib.entry_nr |
+ PCI_DEVID(dev->bus->number, dev->devfn) << 11 |
+ (pci_domain_nr(dev->bus) & 0xFFFFFFFF) << 27;
+}
+
+static inline bool pci_msi_desc_is_multi_msi(struct msi_desc *desc)
+{
+ return !desc->msi_attrib.is_msix && desc->nvec_used > 1;
+}
+
+/**
+ * pci_msi_domain_check_cap - Verify that @domain supports the capabilities for @dev
+ * @domain: The interrupt domain to check
+ * @info: The domain info for verification
+ * @dev: The device to check
+ *
+ * Returns:
+ * 0 if the functionality is supported
+ * 1 if Multi MSI is requested, but the domain does not support it
+ * -ENOTSUPP otherwise
+ */
+int pci_msi_domain_check_cap(struct irq_domain *domain,
+ struct msi_domain_info *info, struct device *dev)
+{
+ struct msi_desc *desc = first_pci_msi_entry(to_pci_dev(dev));
+
+ /* Special handling to support pci_enable_msi_range() */
+ if (pci_msi_desc_is_multi_msi(desc) &&
+ !(info->flags & MSI_FLAG_MULTI_PCI_MSI))
+ return 1;
+ else if (desc->msi_attrib.is_msix && !(info->flags & MSI_FLAG_PCI_MSIX))
+ return -ENOTSUPP;
+
+ return 0;
+}
+
+static int pci_msi_domain_handle_error(struct irq_domain *domain,
+ struct msi_desc *desc, int error)
+{
+ /* Special handling to support pci_enable_msi_range() */
+ if (pci_msi_desc_is_multi_msi(desc) && error == -ENOSPC)
+ return 1;
+
+ return error;
+}
+
+#ifdef GENERIC_MSI_DOMAIN_OPS
+static void pci_msi_domain_set_desc(msi_alloc_info_t *arg,
+ struct msi_desc *desc)
+{
+ arg->desc = desc;
+ arg->hwirq = pci_msi_domain_calc_hwirq(msi_desc_to_pci_dev(desc),
+ desc);
+}
+#else
+#define pci_msi_domain_set_desc NULL
+#endif
+
+static struct msi_domain_ops pci_msi_domain_ops_default = {
+ .set_desc = pci_msi_domain_set_desc,
+ .msi_check = pci_msi_domain_check_cap,
+ .handle_error = pci_msi_domain_handle_error,
+};
+
+static void pci_msi_domain_update_dom_ops(struct msi_domain_info *info)
+{
+ struct msi_domain_ops *ops = info->ops;
+
+ if (ops == NULL) {
+ info->ops = &pci_msi_domain_ops_default;
+ } else {
+ if (ops->set_desc == NULL)
+ ops->set_desc = pci_msi_domain_set_desc;
+ if (ops->msi_check == NULL)
+ ops->msi_check = pci_msi_domain_check_cap;
+ if (ops->handle_error == NULL)
+ ops->handle_error = pci_msi_domain_handle_error;
+ }
+}
+
+static void pci_msi_domain_update_chip_ops(struct msi_domain_info *info)
+{
+ struct irq_chip *chip = info->chip;
+
+ BUG_ON(!chip);
+ if (!chip->irq_write_msi_msg)
+ chip->irq_write_msi_msg = pci_msi_domain_write_msg;
+}
+
+/**
+ * pci_msi_create_irq_domain - Creat a MSI interrupt domain
+ * @node: Optional device-tree node of the interrupt controller
+ * @info: MSI domain info
+ * @parent: Parent irq domain
+ *
+ * Updates the domain and chip ops and creates a MSI interrupt domain.
+ *
+ * Returns:
+ * A domain pointer or NULL in case of failure.
+ */
+struct irq_domain *pci_msi_create_irq_domain(struct device_node *node,
+ struct msi_domain_info *info,
+ struct irq_domain *parent)
+{
+ if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS)
+ pci_msi_domain_update_dom_ops(info);
+ if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
+ pci_msi_domain_update_chip_ops(info);
+
+ return msi_create_irq_domain(node, info, parent);
+}
+
+/**
+ * pci_msi_domain_alloc_irqs - Allocate interrupts for @dev in @domain
+ * @domain: The interrupt domain to allocate from
+ * @dev: The device for which to allocate
+ * @nvec: The number of interrupts to allocate
+ * @type: Unused to allow simpler migration from the arch_XXX interfaces
+ *
+ * Returns:
+ * A virtual interrupt number or an error code in case of failure
+ */
+int pci_msi_domain_alloc_irqs(struct irq_domain *domain, struct pci_dev *dev,
+ int nvec, int type)
+{
+ return msi_domain_alloc_irqs(domain, &dev->dev, nvec);
+}
+
+/**
+ * pci_msi_domain_free_irqs - Free interrupts for @dev in @domain
+ * @domain: The interrupt domain
+ * @dev: The device for which to free interrupts
+ */
+void pci_msi_domain_free_irqs(struct irq_domain *domain, struct pci_dev *dev)
+{
+ msi_domain_free_irqs(domain, &dev->dev);
+}
+
+/**
+ * pci_msi_create_default_irq_domain - Create a default MSI interrupt domain
+ * @node: Optional device-tree node of the interrupt controller
+ * @info: MSI domain info
+ * @parent: Parent irq domain
+ *
+ * Returns: A domain pointer or NULL in case of failure. If successful
+ * the default PCI/MSI irqdomain pointer is updated.
+ */
+struct irq_domain *pci_msi_create_default_irq_domain(struct device_node *node,
+ struct msi_domain_info *info, struct irq_domain *parent)
+{
+ struct irq_domain *domain;
+
+ mutex_lock(&pci_msi_domain_lock);
+ if (pci_msi_default_domain) {
+ pr_err("PCI: default irq domain for PCI MSI has already been created.\n");
+ domain = NULL;
+ } else {
+ domain = pci_msi_create_irq_domain(node, info, parent);
+ pci_msi_default_domain = domain;
+ }
+ mutex_unlock(&pci_msi_domain_lock);
+
+ return domain;
+}
+#endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */