Merge tag 'msi-map-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core

Support for msi-map, and msi-parent update from Marc Zyngier:

- New map-map property to describe the remapping of requester-ids,
  and the routing of MSIs to controllers
- New hooks to make MSI domains per-device if required
- Extension of msi-parent to provide sideband information
- Extensive documentation for both msi-map and msi-parent

1 files changed, 49 insertions, 0 deletions

diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index ddd59fe786f8..4cd6f3abcecf 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -20,6 +20,7 @@
 #include <linux/io.h>
 #include <linux/slab.h>
 #include <linux/irqdomain.h>
+#include <linux/of_irq.h>
 
 #include "pci.h"
 
@@ -1327,4 +1328,52 @@ struct irq_domain *pci_msi_create_default_irq_domain(struct fwnode_handle *fwnod
 
 	return domain;
 }
+
+static int get_msi_id_cb(struct pci_dev *pdev, u16 alias, void *data)
+{
+	u32 *pa = data;
+
+	*pa = alias;
+	return 0;
+}
+/**
+ * pci_msi_domain_get_msi_rid - Get the MSI requester id (RID)
+ * @domain:	The interrupt domain
+ * @pdev:	The PCI device.
+ *
+ * The RID for a device is formed from the alias, with a firmware
+ * supplied mapping applied
+ *
+ * Returns: The RID.
+ */
+u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev)
+{
+	struct device_node *of_node;
+	u32 rid = 0;
+
+	pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid);
+
+	of_node = irq_domain_get_of_node(domain);
+	if (of_node)
+		rid = of_msi_map_rid(&pdev->dev, of_node, rid);
+
+	return rid;
+}
+
+/**
+ * pci_msi_get_device_domain - Get the MSI domain for a given PCI device
+ * @pdev:	The PCI device
+ *
+ * Use the firmware data to find a device-specific MSI domain
+ * (i.e. not one that is ste as a default).
+ *
+ * Returns: The coresponding MSI domain or NULL if none has been found.
+ */
+struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev)
+{
+	u32 rid = 0;
+
+	pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid);
+	return of_msi_map_get_device_domain(&pdev->dev, rid);
+}
 #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */