diff mbox

[11/28] PCI: Introduce pci_host_bridge_ops to setup host bridge

Message ID 1421372666-12288-12-git-send-email-wangyijing@huawei.com (mailing list archive)
State New, archived
Headers show

Commit Message

Yijing Wang Jan. 16, 2015, 1:44 a.m. UTC 
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 {
	/* set root bus speed, some platform need this like powerpc */
	void (*phb_set_root_bus_speed)(struct pci_host_bridge *host);
	/* setup pci_host_bridge before pci_host_bridge be added to driver core */
	int (*phb_prepare)(struct pci_host_bridge *host);
	/* probe whether pci_host_bridge scan mode is of mode */
	void (*phb_probe_mode)(struct pci_host_bridge *);
	/* platform specific of scan hook to scan pci device */
	void (*phb_of_scan_bus)(struct pci_host_bridge *);
}

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
---
 drivers/pci/host-bridge.c |   12 ++++++++++--
 drivers/pci/probe.c       |   19 ++++++++++++++-----
 include/linux/pci.h       |   16 ++++++++++++++--
 3 files changed, 38 insertions(+), 9 deletions(-)

Comments

Arnd Bergmann Jan. 16, 2015, 9:23 a.m. UTC | #1 
On Friday 16 January 2015 09:44:09 Yijing Wang wrote:
> @@ -2064,7 +2073,7 @@ struct pci_bus *pci_scan_root_bus(struct device *parent, u32 db,
>  {
>         struct pci_host_bridge *host;
>  
> -       host = pci_create_host_bridge(parent, db, resources, sysdata);
> +       host = pci_create_host_bridge(parent, db, resources, sysdata, NULL);
>         if (!host)
>                 return NULL;
>  
> 

Same comment as for patch 10: If we leave this out of the pci_create_host_bridge
argument but set it later, þe interface becomes simpler for callers that
don't have custom pci_host_bridge_ops.

This would break your phb_prepare() callback, but I assume a host driver
can just make a direct function call before entering pci_create_host_bridge
for this. Let me know if I'm missing something here.

	Arnd
Arnd Bergmann Jan. 16, 2015, 9:35 a.m. UTC | #2 
On Friday 16 January 2015 10:23:11 Arnd Bergmann wrote:
> On Friday 16 January 2015 09:44:09 Yijing Wang wrote:
> > @@ -2064,7 +2073,7 @@ struct pci_bus *pci_scan_root_bus(struct device *parent, u32 db,
> >  {
> >         struct pci_host_bridge *host;
> >  
> > -       host = pci_create_host_bridge(parent, db, resources, sysdata);
> > +       host = pci_create_host_bridge(parent, db, resources, sysdata, NULL);
> >         if (!host)
> >                 return NULL;
> >  
> > 
> 
> Same comment as for patch 10: If we leave this out of the pci_create_host_bridge
> argument but set it later, þe interface becomes simpler for callers that
> don't have custom pci_host_bridge_ops.
> 
> This would break your phb_prepare() callback, but I assume a host driver
> can just make a direct function call before entering pci_create_host_bridge
> for this. Let me know if I'm missing something here.

I've read the later patches now that explain why it's needed, so nevermind
my comment above.

	Arnd
diff mbox

Patch

diff --git a/drivers/pci/host-bridge.c b/drivers/pci/host-bridge.c
index 0b6ba5c..ccbf168 100644
--- a/drivers/pci/host-bridge.c
+++ b/drivers/pci/host-bridge.c
@@ -23,8 +23,8 @@  static void pci_release_host_bridge_dev(struct device *dev)
 }
 
 struct pci_host_bridge *pci_create_host_bridge(
-		struct device *parent, u32 db, 
-		struct list_head *resources, void *sysdata)
+		struct device *parent, u32 db, struct list_head *resources,
+		void *sysdata, struct pci_host_bridge_ops *ops)
 {
 	int error;
 	int bus = PCI_BUSNUM(db);
@@ -56,6 +56,7 @@  struct pci_host_bridge *pci_create_host_bridge(
 		}
 	mutex_unlock(&phb_mutex);
 
+	host->ops = ops;
 	host->dev.parent = parent;
 	INIT_LIST_HEAD(&host->windows);
 	host->dev.release = pci_release_host_bridge_dev;
@@ -63,6 +64,13 @@  struct pci_host_bridge *pci_create_host_bridge(
 	dev_set_name(&host->dev, "pci%04x:%02x", host->domain, 
 			host->busnum);
 
+	if (host->ops && host->ops->phb_prepare) {
+		error = host->ops->phb_prepare(host);
+		if(error) {
+			kfree(host);
+			return NULL;
+		}
+	}
 	error = device_register(&host->dev);
 	if (error) {
 		put_device(&host->dev);
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 98a8d97..5f748ed 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1888,6 +1888,8 @@  static struct pci_bus *__pci_create_root_bus(
 
 	bridge->bus = b;
 	b->bridge = get_device(&bridge->dev);
+	if (bridge->ops && bridge->ops->phb_set_root_bus_speed)
+		bridge->ops->phb_set_root_bus_speed(bridge);
 	error = pcibios_root_bridge_prepare(bridge);
 	if (error)
 		goto err_out;
@@ -1953,7 +1955,7 @@  struct pci_bus *pci_create_root_bus(struct device *parent, u32 db,
 {
 	struct pci_host_bridge *host;
 
-	host = pci_create_host_bridge(parent, db, resources, sysdata);
+	host = pci_create_host_bridge(parent, db, resources, sysdata, NULL);
 	if (!host)
 		return NULL;
 	
@@ -2051,10 +2053,17 @@  static struct pci_bus *__pci_scan_root_bus(
 		pci_bus_insert_busn_res(b, host->busnum, 255);
 	}
 
-	max = pci_scan_child_bus(b);
+	if (host->ops && host->ops->phb_probe_mode)
+		host->ops->phb_probe_mode(host);
 
-	if (!found)
-		pci_bus_update_busn_res_end(b, max);
+	if (host->of_scan) {
+		if (host->ops &&host->ops->phb_of_scan_bus)
+			host->ops->phb_of_scan_bus(host);
+	} else {
+		max = pci_scan_child_bus(b);
+		if (!found)
+			pci_bus_update_busn_res_end(b, max);
+	}
 
 	return b;
 }
@@ -2064,7 +2073,7 @@  struct pci_bus *pci_scan_root_bus(struct device *parent, u32 db,
 {
 	struct pci_host_bridge *host;
 
-	host = pci_create_host_bridge(parent, db, resources, sysdata);
+	host = pci_create_host_bridge(parent, db, resources, sysdata, NULL);
 	if (!host)
 		return NULL;
 
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 3ee8436..c06b95d 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -401,13 +401,25 @@  struct pci_host_bridge_window {
 	resource_size_t offset;		/* bus address + offset = CPU address */
 };
 
+struct pci_host_bridge;
+struct pci_host_bridge_ops {
+	void (*phb_set_root_bus_speed)(struct pci_host_bridge *host);
+	int (*phb_prepare)(struct pci_host_bridge *host);
+	/* Override domain number by host specific .phv_assign_domain_nr()  */
+	void (*phb_assign_domain_nr)(struct pci_host_bridge *);
+	void (*phb_probe_mode)(struct pci_host_bridge *);
+	void (*phb_of_scan_bus)(struct pci_host_bridge *);
+};
+
 struct pci_host_bridge {
 	u16	domain;
 	u16 busnum;
+	bool of_scan;
 	struct device dev;
 	struct pci_bus *bus;		/* root bus */
 	struct list_head list;
 	struct list_head windows;	/* pci_host_bridge_windows */
+	struct pci_host_bridge_ops *ops;
 	void (*release_fn)(struct pci_host_bridge *);
 	void *release_data;
 };
@@ -419,8 +431,8 @@  void pci_set_host_bridge_release(struct pci_host_bridge *bridge,
 
 int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge);
 struct pci_host_bridge *pci_create_host_bridge(
-		struct device *parent, u32 dombus, 
-		struct list_head *resources, void *sysdata);
+		struct device *parent, u32 dombus, struct list_head *resources,
+		void *sysdata, struct pci_host_bridge_ops *ops);
 /*
  * The first PCI_BRIDGE_RESOURCE_NUM PCI bus resources (those that correspond
  * to P2P or CardBus bridge windows) go in a table.  Additional ones (for