PCI/MSI: Add support for OF-provided msi_domain
In order to populate the PCI host bridge msi_domain, use the
"msi-parent" attribute to lookup a corresponding irq domain.
If found, this is our MSI domain.
This gets plugged into the core PCI code.
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: Yijing Wang <wangyijing@huawei.com>
Cc: Ma Jun <majun258@huawei.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Duc Dang <dhdang@apm.com>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1438091186-10244-6-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/drivers/pci/of.c b/drivers/pci/of.c
index f092993..85844d8 100644
--- a/drivers/pci/of.c
+++ b/drivers/pci/of.c
@@ -9,6 +9,7 @@
* 2 of the License, or (at your option) any later version.
*/
+#include <linux/irqdomain.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/of.h>
@@ -59,3 +60,27 @@
return of_node_get(bus->bridge->parent->of_node);
return NULL;
}
+
+struct irq_domain *pci_host_bridge_of_msi_domain(struct pci_bus *bus)
+{
+#ifdef CONFIG_IRQ_DOMAIN
+ struct device_node *np;
+ struct irq_domain *d;
+
+ if (!bus->dev.of_node)
+ return NULL;
+
+ /* Start looking for a phandle to an MSI controller. */
+ np = of_parse_phandle(bus->dev.of_node, "msi-parent", 0);
+ if (!np)
+ return NULL;
+
+ d = irq_find_matching_host(np, DOMAIN_BUS_PCI_MSI);
+ if (d)
+ return d;
+
+ return irq_find_host(np);
+#else
+ return NULL;
+#endif
+}