[PATCH v5 05/19] PCI/MSI: of: Add support for OF-provided msi_domain

Marc Zyngier
2015-07-23T09:27:16Z

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.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
drivers/pci/of.c | 21 +++++++++++++++++++++
drivers/pci/probe.c | 5 ++++-
include/linux/pci.h | 4 ++++
3 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/of.c b/drivers/pci/of.c
index f092993..e2ebb7d 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 +60,23 @@ struct device_node * __weak pcibios_get_phb_of_node(struct pci_bus *bus)
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;
+ 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)
+ d = irq_find_host(np);
+ return d;
+#else
+ return NULL;
+#endif
+}
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 2fd4f8e..b30eb6e 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -663,12 +663,15 @@ static void pci_set_bus_speed(struct pci_bus *bus)

static struct irq_domain *pci_host_bridge_msi_domain(struct pci_bus *bus)
{
+ struct irq_domain *d;
+
/*
* Any firmware interface that can resolve the msi_domain
* should be called from here.
*/
+ d = pci_host_bridge_of_msi_domain(bus);

- return NULL;
+ return d;
}

static void pci_set_bus_msi_domain(struct pci_bus *bus)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index fbf245f..772616d 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1841,10 +1841,12 @@ int pci_vpd_find_info_keyword(const u8 *buf, unsigned int off,
/* PCI <-> OF binding helpers */
#ifdef CONFIG_OF
struct device_node;
+struct irq_domain;
void pci_set_of_node(struct pci_dev *dev);
void pci_release_of_node(struct pci_dev *dev);
void pci_set_bus_of_node(struct pci_bus *bus);
void pci_release_bus_of_node(struct pci_bus *bus);
+struct irq_domain *pci_host_bridge_of_msi_domain(struct pci_bus *bus);

/* Arch may override this (weak) */
struct device_node *pcibios_get_phb_of_node(struct pci_bus *bus);
@@ -1867,6 +1869,8 @@ static inline void pci_set_bus_of_node(struct pci_bus *bus) { }
static inline void pci_release_bus_of_node(struct pci_bus *bus) { }
static inline struct device_node *
pci_device_to_OF_node(const struct pci_dev *pdev) { return NULL; }
+static inline struct irq_domain *
+pci_host_bridge_of_msi_domain(struct pci_bus *bus) { return NULL; }
#endif /* CONFIG_OF */

#ifdef CONFIG_EEH
--
2.1.4