summaryrefslogtreecommitdiffstats
path: root/drivers/pci
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/pci')
-rw-r--r--drivers/pci/msi/api.c67
-rw-r--r--drivers/pci/msi/irqdomain.c3
2 files changed, 69 insertions, 1 deletions
diff --git a/drivers/pci/msi/api.c b/drivers/pci/msi/api.c
index 2d46a0cfd541..c8816db91e9c 100644
--- a/drivers/pci/msi/api.c
+++ b/drivers/pci/msi/api.c
@@ -113,6 +113,73 @@ int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries,
EXPORT_SYMBOL(pci_enable_msix_range);
/**
+ * pci_msix_can_alloc_dyn - Query whether dynamic allocation after enabling
+ * MSI-X is supported
+ *
+ * @dev: PCI device to operate on
+ *
+ * Return: True if supported, false otherwise
+ */
+bool pci_msix_can_alloc_dyn(struct pci_dev *dev)
+{
+ if (!dev->msix_cap)
+ return false;
+
+ return pci_msi_domain_supports(dev, MSI_FLAG_PCI_MSIX_ALLOC_DYN, DENY_LEGACY);
+}
+EXPORT_SYMBOL_GPL(pci_msix_can_alloc_dyn);
+
+/**
+ * pci_msix_alloc_irq_at - Allocate an MSI-X interrupt after enabling MSI-X
+ * at a given MSI-X vector index or any free vector index
+ *
+ * @dev: PCI device to operate on
+ * @index: Index to allocate. If @index == MSI_ANY_INDEX this allocates
+ * the next free index in the MSI-X table
+ * @affdesc: Optional pointer to an affinity descriptor structure. NULL otherwise
+ *
+ * Return: A struct msi_map
+ *
+ * On success msi_map::index contains the allocated index (>= 0) and
+ * msi_map::virq contains the allocated Linux interrupt number (> 0).
+ *
+ * On fail msi_map::index contains the error code and msi_map::virq
+ * is set to 0.
+ */
+struct msi_map pci_msix_alloc_irq_at(struct pci_dev *dev, unsigned int index,
+ const struct irq_affinity_desc *affdesc)
+{
+ struct msi_map map = { .index = -ENOTSUPP };
+
+ if (!dev->msix_enabled)
+ return map;
+
+ if (!pci_msix_can_alloc_dyn(dev))
+ return map;
+
+ return msi_domain_alloc_irq_at(&dev->dev, MSI_DEFAULT_DOMAIN, index, affdesc, NULL);
+}
+EXPORT_SYMBOL_GPL(pci_msix_alloc_irq_at);
+
+/**
+ * pci_msix_free_irq - Free an interrupt on a PCI/MSIX interrupt domain
+ * which was allocated via pci_msix_alloc_irq_at()
+ *
+ * @dev: The PCI device to operate on
+ * @map: A struct msi_map describing the interrupt to free
+ * as returned from the allocation function.
+ */
+void pci_msix_free_irq(struct pci_dev *dev, struct msi_map map)
+{
+ if (WARN_ON_ONCE(map.index < 0 || map.virq <= 0))
+ return;
+ if (WARN_ON_ONCE(!pci_msix_can_alloc_dyn(dev)))
+ return;
+ msi_domain_free_irqs_range(&dev->dev, MSI_DEFAULT_DOMAIN, map.index, map.index);
+}
+EXPORT_SYMBOL_GPL(pci_msix_free_irq);
+
+/**
* pci_disable_msix() - Disable MSI-X interrupt mode on device
* @dev: the PCI device to operate on
*
diff --git a/drivers/pci/msi/irqdomain.c b/drivers/pci/msi/irqdomain.c
index 8afaef10b939..deb1930b4e66 100644
--- a/drivers/pci/msi/irqdomain.c
+++ b/drivers/pci/msi/irqdomain.c
@@ -225,7 +225,8 @@ static const struct msi_domain_template pci_msix_template = {
},
.info = {
- .flags = MSI_COMMON_FLAGS | MSI_FLAG_PCI_MSIX,
+ .flags = MSI_COMMON_FLAGS | MSI_FLAG_PCI_MSIX |
+ MSI_FLAG_PCI_MSIX_ALLOC_DYN,
.bus_token = DOMAIN_BUS_PCI_DEVICE_MSIX,
},
};