From: David Daney <david.daney@xxxxxxxxxx>
Add pci_msi_domain_get_msi_rid() to return the MSI requester id (RID).
Initially needed by gic-v3 based systems. It will be used by follow on
patch to drivers/irqchip/irq-gic-v3-its-pci-msi.c
Initially supports mapping the RID via OF device tree. In the future,
this could be extended to use ACPI _IORT tables as well.
Reviewed-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Signed-off-by: David Daney <david.daney@xxxxxxxxxx>
---
drivers/pci/msi.c | 30 ++++++++++++++++++++++++++++++
include/linux/msi.h | 1 +
2 files changed, 31 insertions(+)
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index d449714..81a2798 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 +1328,33 @@ struct irq_domain *pci_msi_create_default_irq_domain(struct device_node *node,
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)
+{
+ u32 rid = 0;
+
+ pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid);
+
+ if (domain->of_node)
+ rid = of_msi_map_rid(&pdev->dev, domain->of_node, rid);
+
+ return rid;
+}
#endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */
diff --git a/include/linux/msi.h b/include/linux/msi.h
index ad939d0..56e3b76 100644
--- a/include/linux/msi.h
+++ b/include/linux/msi.h
@@ -293,6 +293,7 @@ irq_hw_number_t pci_msi_domain_calc_hwirq(struct pci_dev *dev,
struct msi_desc *desc);
int pci_msi_domain_check_cap(struct irq_domain *domain,
struct msi_domain_info *info, struct device *dev);
+u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev);
#endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */
#endif /* LINUX_MSI_H */
--
1.9.1
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
