acpi: pci: Setup MSI domain for ACPI based pci devices
This patch introduces pci_msi_register_fwnode_provider() for irqchip
to register a callback, to provide a way to determine appropriate MSI
domain for a pci device.
It also introduces pci_host_bridge_acpi_msi_domain(), which returns
the MSI domain of the specified PCI host bridge with DOMAIN_BUS_PCI_MSI
bus token. Then, it is assigned to pci device.
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index a32ba75..d3f32d6 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -9,7 +9,9 @@
#include <linux/delay.h>
#include <linux/init.h>
+#include <linux/irqdomain.h>
#include <linux/pci.h>
+#include <linux/msi.h>
#include <linux/pci_hotplug.h>
#include <linux/module.h>
#include <linux/pci-aspm.h>
@@ -689,6 +691,46 @@
.cleanup = pci_acpi_cleanup,
};
+
+static struct fwnode_handle *(*pci_msi_get_fwnode_cb)(struct device *dev);
+
+/**
+ * pci_msi_register_fwnode_provider - Register callback to retrieve fwnode
+ * @fn: Callback matching a device to a fwnode that identifies a PCI
+ * MSI domain.
+ *
+ * This should be called by irqchip driver, which is the parent of
+ * the MSI domain to provide callback interface to query fwnode.
+ */
+void
+pci_msi_register_fwnode_provider(struct fwnode_handle *(*fn)(struct device *))
+{
+ pci_msi_get_fwnode_cb = fn;
+}
+
+/**
+ * pci_host_bridge_acpi_msi_domain - Retrieve MSI domain of a PCI host bridge
+ * @bus: The PCI host bridge bus.
+ *
+ * This function uses the callback function registered by
+ * pci_msi_register_fwnode_provider() to retrieve the irq_domain with
+ * type DOMAIN_BUS_PCI_MSI of the specified host bridge bus.
+ * This returns NULL on error or when the domain is not found.
+ */
+struct irq_domain *pci_host_bridge_acpi_msi_domain(struct pci_bus *bus)
+{
+ struct fwnode_handle *fwnode;
+
+ if (!pci_msi_get_fwnode_cb)
+ return NULL;
+
+ fwnode = pci_msi_get_fwnode_cb(&bus->dev);
+ if (!fwnode)
+ return NULL;
+
+ return irq_find_matching_fwnode(fwnode, DOMAIN_BUS_PCI_MSI);
+}
+
static int __init acpi_pci_init(void)
{
int ret;