[PATCH v8 14/30] PCI: Introduce pci_host_bridge_ops to support host specific operations

Yijing Wang
2015-03-24T03:34:08Z

Now we have weak functions like pcibios_root_bridge_prepare()
to setup pci host bridge, We could introduce pci_host_bridge_ops
which contain host bridge specific ops to setup pci_host_bridge.
Then host bridge driver could add pci_host_bridge_ops hooks
intead of weak function to setup pci_host_bridge.
This patch add following pci_host_bridge_ops hooks:

pci_host_bridge_ops {
struct pci_ops *ops;
/* set root bus speed, some platform need this like powerpc */
void (*set_root_bus_speed)(struct pci_host_bridge *host);
/* setup pci_host_bridge before pci_host_bridge be added to driver core */
int (*prepare)(struct pci_host_bridge *host);
/* platform specific of scan hook to scan pci device */
int (*scan_bus)(struct pci_host_bridge *);
}
We could easily extend it to support different host bridge
specific operations.

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
---
drivers/pci/host-bridge.c | 9 ++++++++-
drivers/pci/pci.h | 5 +++--
drivers/pci/probe.c | 11 ++++++++---
include/linux/pci.h | 9 +++++++++
4 files changed, 28 insertions(+), 6 deletions(-)

diff --git a/drivers/pci/host-bridge.c b/drivers/pci/host-bridge.c
index 87c4fc5..b439264 100644
--- a/drivers/pci/host-bridge.c
+++ b/drivers/pci/host-bridge.c
@@ -63,7 +63,8 @@ static bool pci_host_busn_res_overlap(

struct pci_host_bridge *pci_create_host_bridge(
struct device *parent, int domain, int bus,
- void *sysdata, struct list_head *resources)
+ void *sysdata, struct list_head *resources,
+ struct pci_host_bridge_ops *ops)
{
int error;
struct pci_host_bridge *host, *tmp;
@@ -98,10 +99,16 @@ struct pci_host_bridge *pci_create_host_bridge(
list_add_tail(&host->list, &pci_host_bridge_list);
mutex_unlock(&pci_host_mutex);

+ host->ops = ops;
host->dev.release = pci_release_host_bridge_dev;
dev_set_drvdata(&host->dev, sysdata);
dev_set_name(&host->dev, "pci%04x:%02x",
host->domain, bus);
+ if (host->ops && host->ops->prepare) {
+ error = host->ops->prepare(host);
+ if (error)
+ goto list_del;
+ }

error = pcibios_root_bridge_prepare(host);
if (error)
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 027fba0..ef10cc1 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -334,8 +334,9 @@ static inline void pci_host_assign_domain_nr(struct pci_host_bridge *host)
}
#endif

-struct pci_host_bridge *pci_create_host_bridge(struct device *parent,
- int domain, int bus, void *sysdata, struct list_head *resources);
+struct pci_host_bridge *pci_create_host_bridge(
+ struct device *parent, int domain, int bus, void *sysdata,
+ struct list_head *resources, struct pci_host_bridge_ops *ops);
void pci_free_host_bridge(struct pci_host_bridge *host);

static inline int pci_host_first_busnr(struct pci_host_bridge *host)
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index ee17d9a..36dfee0 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1894,6 +1894,8 @@ static struct pci_bus *__pci_create_root_bus(
bridge->bus = b;
b->bridge = get_device(&bridge->dev);

+ if (bridge->ops && bridge->ops->set_root_bus_speed)
+ bridge->ops->set_root_bus_speed(bridge);
pcibios_set_root_bus_speed(bridge);
device_enable_async_suspend(b->bridge);
pci_set_bus_of_node(b);
@@ -1958,7 +1960,7 @@ struct pci_bus *pci_create_root_bus(struct device *parent,
struct pci_host_bridge *host;

host = pci_create_host_bridge(parent, domain, bus,
- sysdata, resources);
+ sysdata, resources, NULL);
if (!host)
return NULL;

@@ -2048,7 +2050,10 @@ static struct pci_bus *__pci_scan_root_bus(
if (!b)
return NULL;

- max = pci_scan_child_bus(b);
+ if (host->ops && host->ops->scan_bus)
+ max = host->ops->scan_bus(host);
+ else
+ max = pci_scan_child_bus(b);

/* If default busn resource used, update the max bus number */
if (host->busn_res.flags & IORESOURCE_BUS) {
@@ -2066,7 +2071,7 @@ struct pci_bus *pci_scan_root_bus(struct device *parent, int domain,
struct pci_host_bridge *host;

host = pci_create_host_bridge(parent, domain, bus,
- sysdata, resources);
+ sysdata, resources, NULL);
if (!host)
return NULL;

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 91cba01..2702a51 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -400,6 +400,14 @@ static inline int pci_channel_offline(struct pci_dev *pdev)
return (pdev->error_state != pci_channel_io_normal);
}

+struct pci_host_bridge;
+struct pci_host_bridge_ops {
+ struct pci_ops *pci_ops;
+ int (*prepare)(struct pci_host_bridge *host);
+ void (*set_root_bus_speed)(struct pci_host_bridge *host);
+ int (*scan_bus)(struct pci_host_bridge *host);
+};
+
struct pci_host_bridge {
int domain;
struct device dev;
@@ -408,6 +416,7 @@ struct pci_host_bridge {
struct resource busn_res;
struct list_head windows; /* resource_entry */
struct list_head list;
+ struct pci_host_bridge_ops *ops;
void (*release_fn)(struct pci_host_bridge *);
void *release_data;
};
--
1.7.1