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path: root/drivers/pci/msi.c
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Diffstat (limited to 'drivers/pci/msi.c')
-rw-r--r--drivers/pci/msi.c160
1 files changed, 158 insertions, 2 deletions
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 0e6d04d7ba4..a825d78fd0a 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -86,6 +86,31 @@ void default_teardown_msi_irqs(struct pci_dev *dev)
}
#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 pos, int enable)
{
u16 control;
@@ -323,6 +348,18 @@ static void free_msi_irqs(struct pci_dev *dev)
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);
}
@@ -360,7 +397,7 @@ static void __pci_restore_msi_state(struct pci_dev *dev)
pci_intx_for_msi(dev, 0);
msi_set_enable(dev, pos, 0);
- write_msi_msg(dev->irq, &entry->msg);
+ arch_restore_msi_irqs(dev, dev->irq);
pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
msi_mask_irq(entry, msi_capable_mask(control), entry->masked);
@@ -388,7 +425,7 @@ static void __pci_restore_msix_state(struct pci_dev *dev)
pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
list_for_each_entry(entry, &dev->msi_list, list) {
- write_msi_msg(entry->irq, &entry->msg);
+ arch_restore_msi_irqs(dev, entry->irq);
msix_mask_irq(entry, entry->masked);
}
@@ -403,6 +440,98 @@ void pci_restore_msi_state(struct pci_dev *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);
+
+
+struct attribute *msi_irq_default_attrs[] = {
+ &mode_attribute.attr,
+ NULL
+};
+
+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
@@ -454,6 +583,13 @@ static int msi_capability_init(struct pci_dev *dev, int nvec)
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, pos, 1);
@@ -574,6 +710,12 @@ static int msix_capability_init(struct pci_dev *dev,
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;
@@ -732,6 +874,8 @@ void pci_disable_msi(struct pci_dev *dev)
pci_msi_shutdown(dev);
free_msi_irqs(dev);
+ kset_unregister(dev->msi_kset);
+ dev->msi_kset = NULL;
}
EXPORT_SYMBOL(pci_disable_msi);
@@ -830,6 +974,8 @@ void pci_disable_msix(struct pci_dev *dev)
pci_msix_shutdown(dev);
free_msi_irqs(dev);
+ kset_unregister(dev->msi_kset);
+ dev->msi_kset = NULL;
}
EXPORT_SYMBOL(pci_disable_msix);
@@ -870,5 +1016,15 @@ EXPORT_SYMBOL(pci_msi_enabled);
void pci_msi_init_pci_dev(struct pci_dev *dev)
{
+ int pos;
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.
+ */
+ pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
+ if (pos)
+ msi_set_enable(dev, pos, 0);
+ msix_set_enable(dev, 0);
}