PCI/MSI: Add hooks to populate the msi_domain field

In order to be able to populate the device msi_domain field,
add the necessary hooks to propagate the host bridge msi_domain
across secondary busses to devices.

So far, nobody populates the initial msi_domain.

Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
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: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1438091186-10244-5-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index cefd636..c03ecbf 100644 (file)
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -661,6 +661,32 @@ static void pci_set_bus_speed(struct pci_bus *bus)
        }
 }
 
+static struct irq_domain *pci_host_bridge_msi_domain(struct pci_bus *bus)
+{
+       /*
+        * Any firmware interface that can resolve the msi_domain
+        * should be called from here.
+        */
+
+       return NULL;
+}
+
+static void pci_set_bus_msi_domain(struct pci_bus *bus)
+{
+       struct irq_domain *d;
+
+       /*
+        * Either bus is the root, and we must obtain it from the
+        * firmware, or we inherit it from the bridge device.
+        */
+       if (pci_is_root_bus(bus))
+               d = pci_host_bridge_msi_domain(bus);
+       else
+               d = dev_get_msi_domain(&bus->self->dev);
+
+       dev_set_msi_domain(&bus->dev, d);
+}
+
 static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
                                           struct pci_dev *bridge, int busnr)
 {
@@ -714,6 +740,7 @@ static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
        bridge->subordinate = child;
 
 add_dev:
+       pci_set_bus_msi_domain(child);
        ret = device_register(&child->dev);
        WARN_ON(ret < 0);
 
@@ -1544,6 +1571,17 @@ static void pci_init_capabilities(struct pci_dev *dev)
        pci_enable_acs(dev);
 }
 
+static void pci_set_msi_domain(struct pci_dev *dev)
+{
+       /*
+        * If no domain has been set through the pcibios_add_device
+        * callback, inherit the default from the bus device.
+        */
+       if (!dev_get_msi_domain(&dev->dev))
+               dev_set_msi_domain(&dev->dev,
+                                  dev_get_msi_domain(&dev->bus->dev));
+}
+
 void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
 {
        int ret;
@@ -1585,6 +1623,9 @@ void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
        ret = pcibios_add_device(dev);
        WARN_ON(ret < 0);
 
+       /* Setup MSI irq domain */
+       pci_set_msi_domain(dev);
+
        /* Notifier could use PCI capabilities */
        dev->match_driver = false;
        ret = device_add(&dev->dev);
@@ -1975,6 +2016,7 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
        b->bridge = get_device(&bridge->dev);
        device_enable_async_suspend(b->bridge);
        pci_set_bus_of_node(b);
+       pci_set_bus_msi_domain(b);
 
        if (!parent)
                set_dev_node(b->bridge, pcibus_to_node(b));