[PATCH v7 4/6] pci: Introduce a domain number for pci_host_bridge.

Liviu Dudau
2014-03-14T15:34:30Z

Make it easier to discover the domain number of a bus by storing
the number in pci_host_bridge for the root bus. Several architectures
have their own way of storing this information, so it makes sense
to try to unify the code. While at this, add a new function that
creates a root bus in a given domain and make pci_create_root_bus()
a wrapper around this function.

Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
Tested-by: Tanmay Inamdar <tinamdar@apm.com>
---
drivers/pci/probe.c | 41 +++++++++++++++++++++++++++++++++--------
include/linux/pci.h | 4 ++++
2 files changed, 37 insertions(+), 8 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index fd11c12..172c615 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1714,8 +1714,9 @@ void __weak pcibios_remove_bus(struct pci_bus *bus)
{
}

-struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
- struct pci_ops *ops, void *sysdata, struct list_head *resources)
+struct pci_bus *pci_create_root_bus_in_domain(struct device *parent,
+ int domain, int bus, struct pci_ops *ops, void *sysdata,
+ struct list_head *resources)
{
int error;
struct pci_host_bridge *bridge;
@@ -1728,30 +1729,34 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,

bridge = pci_alloc_host_bridge();
if (!bridge)
- return NULL;
+ return ERR_PTR(-ENOMEM);

bridge->dev.parent = parent;
bridge->dev.release = pci_release_host_bridge_dev;
+ bridge->domain_nr = domain;
error = pcibios_root_bridge_prepare(bridge);
if (error)
goto err_out;

b = pci_alloc_bus();
- if (!b)
+ if (!b) {
+ error = -ENOMEM;
goto err_out;
+ }

b->sysdata = sysdata;
b->ops = ops;
b->number = b->busn_res.start = bus;
- b2 = pci_find_bus(pci_domain_nr(b), bus);
+ b2 = pci_find_bus(bridge->domain_nr, bus);
if (b2) {
/* If we already got to this bus through a different bridge, ignore it */
dev_dbg(&b2->dev, "bus already known\n");
+ error = -EEXIST;
goto err_bus_out;
}

bridge->bus = b;
- dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus);
+ dev_set_name(&bridge->dev, "pci%04x:%02x", bridge->domain_nr, bus);
error = device_register(&bridge->dev);
if (error) {
put_device(&bridge->dev);
@@ -1766,7 +1771,7 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,

b->dev.class = &pcibus_class;
b->dev.parent = b->bridge;
- dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus);
+ dev_set_name(&b->dev, "%04x:%02x", bridge->domain_nr, bus);
error = device_register(&b->dev);
if (error)
goto class_dev_reg_err;
@@ -1816,7 +1821,27 @@ err_bus_out:
kfree(b);
err_out:
kfree(bridge);
- return NULL;
+ return ERR_PTR(error);
+}
+
+struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
+ struct pci_ops *ops, void *sysdata, struct list_head *resources)
+{
+ int domain_nr;
+ struct pci_bus *b = pci_alloc_bus();
+ if (!b)
+ return NULL;
+
+ b->sysdata = sysdata;
+ domain_nr = pci_domain_nr(b);
+ kfree(b);
+
+ b = pci_create_root_bus_in_domain(parent, domain_nr, bus,
+ ops, sysdata, resources);
+ if (IS_ERR(b))
+ return NULL;
+
+ return b;
}

int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 33aa2ca..1eed009 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -394,6 +394,7 @@ struct pci_host_bridge_window {
struct pci_host_bridge {
struct device dev;
struct pci_bus *bus; /* root bus */
+ int domain_nr;
struct list_head windows; /* pci_host_bridge_windows */
void (*release_fn)(struct pci_host_bridge *);
void *release_data;
@@ -747,6 +748,9 @@ struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops, void *sysdata);
struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
struct pci_ops *ops, void *sysdata,
struct list_head *resources);
+struct pci_bus *pci_create_root_bus_in_domain(struct device *parent,
+ int domain, int bus, struct pci_ops *ops,
+ void *sysdata, struct list_head *resources);
int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int busmax);
int pci_bus_update_busn_res_end(struct pci_bus *b, int busmax);
void pci_bus_release_busn_res(struct pci_bus *b);
--
1.9.0