1 files changed, 73 insertions, 0 deletions
diff --git a/include/linux/msi_api.h b/include/linux/msi_api.h
new file mode 100644
index 000000000..391087ad9
--- /dev/null
+++ b/include/linux/msi_api.h
@@ -0,0 +1,73 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef LINUX_MSI_API_H
+#define LINUX_MSI_API_H
+
+/*
+ * APIs which are relevant for device driver code for allocating and
+ * freeing MSI interrupts and querying the associations between
+ * hardware/software MSI indices and the Linux interrupt number.
+ */
+
+struct device;
+
+/*
+ * Per device interrupt domain related constants.
+ */
+enum msi_domain_ids {
+	MSI_DEFAULT_DOMAIN,
+	MSI_SECONDARY_DOMAIN,
+	MSI_MAX_DEVICE_IRQDOMAINS,
+};
+
+/**
+ * union msi_instance_cookie - MSI instance cookie
+ * @value:	u64 value store
+ * @ptr:	Pointer to usage site specific data
+ *
+ * This cookie is handed to the IMS allocation function and stored in the
+ * MSI descriptor for the interrupt chip callbacks.
+ *
+ * The content of this cookie is MSI domain implementation defined.  For
+ * PCI/IMS implementations this could be a PASID or a pointer to queue
+ * memory.
+ */
+union msi_instance_cookie {
+	u64	value;
+	void	*ptr;
+};
+
+/**
+ * msi_map - Mapping between MSI index and Linux interrupt number
+ * @index:	The MSI index, e.g. slot in the MSI-X table or
+ *		a software managed index if >= 0. If negative
+ *		the allocation function failed and it contains
+ *		the error code.
+ * @virq:	The associated Linux interrupt number
+ */
+struct msi_map {
+	int	index;
+	int	virq;
+};
+
+/*
+ * Constant to be used for dynamic allocations when the allocation is any
+ * free MSI index, which is either an entry in a hardware table or a
+ * software managed index.
+ */
+#define MSI_ANY_INDEX		UINT_MAX
+
+unsigned int msi_domain_get_virq(struct device *dev, unsigned int domid, unsigned int index);
+
+/**
+ * msi_get_virq - Lookup the Linux interrupt number for a MSI index on the default interrupt domain
+ * @dev:	Device for which the lookup happens
+ * @index:	The MSI index to lookup
+ *
+ * Return: The Linux interrupt number on success (> 0), 0 if not found
+ */
+static inline unsigned int msi_get_virq(struct device *dev, unsigned int index)
+{
+	return msi_domain_get_virq(dev, MSI_DEFAULT_DOMAIN, index);
+}
+
+#endif