Commit 5a21d70d authored by Bjorn Helgaas's avatar Bjorn Helgaas
Browse files

PCI: add struct pci_host_bridge and a list of all bridges found 



This adds a list of all PCI host bridges we find and a way to look up
the host bridge from a pci_dev.

Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent a5390aa6

drivers/pci/probe.c

+34 −5
Original line number Diff line number Diff line
@@ -15,6 +15,8 @@ 
#define CARDBUS_LATENCY_TIMER	176	/* secondary latency timer */

#define CARDBUS_RESERVE_BUSNR	3



static LIST_HEAD(pci_host_bridges);



/* Ugh.  Need to stop exporting this to modules. */

LIST_HEAD(pci_root_buses);

EXPORT_SYMBOL(pci_root_buses);
@@ -42,6 +44,23 @@ int no_pci_devices(void) 
}

EXPORT_SYMBOL(no_pci_devices);



static struct pci_host_bridge *pci_host_bridge(struct pci_dev *dev)

{

	struct pci_bus *bus;

	struct pci_host_bridge *bridge;



	bus = dev->bus;

	while (bus->parent)

		bus = bus->parent;



	list_for_each_entry(bridge, &pci_host_bridges, list) {

		if (bridge->bus == bus)

			return bridge;

	}



	return NULL;

}



/*

 * PCI Bus Class

 */
@@ -1544,20 +1563,23 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, 
		struct pci_ops *ops, void *sysdata, struct list_head *resources)

{

	int error, i;

	struct pci_host_bridge *bridge;

	struct pci_bus *b, *b2;

	struct device *dev;

	struct pci_bus_resource *bus_res, *n;

	struct resource *res;



	bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);

	if (!bridge)

		return NULL;



	b = pci_alloc_bus();

	if (!b)

		return NULL;

		goto err_bus;



	dev = kzalloc(sizeof(*dev), GFP_KERNEL);

	if (!dev) {

		kfree(b);

		return NULL;

	}

	if (!dev)

		goto err_dev;



	b->sysdata = sysdata;

	b->ops = ops;
@@ -1594,6 +1616,8 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, 


	b->number = b->secondary = bus;



	bridge->bus = b;



	/* Add initial resources to the bus */

	list_for_each_entry_safe(bus_res, n, resources, list)

		list_move_tail(&bus_res->list, &b->resources);
@@ -1609,6 +1633,7 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, 
	}



	down_write(&pci_bus_sem);

	list_add_tail(&bridge->list, &pci_host_bridges);

	list_add_tail(&b->node, &pci_root_buses);

	up_write(&pci_bus_sem);
@@ -1618,11 +1643,15 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, 
	device_unregister(dev);

dev_reg_err:

	down_write(&pci_bus_sem);

	list_del(&bridge->list);

	list_del(&b->node);

	up_write(&pci_bus_sem);

err_out:

	kfree(dev);

err_dev:

	kfree(b);

err_bus:

	kfree(bridge);

	return NULL;

}

include/linux/pci.h

+5 −0
Original line number Diff line number Diff line
@@ -368,6 +368,11 @@ static inline int pci_channel_offline(struct pci_dev *pdev) 
	return (pdev->error_state != pci_channel_io_normal);

}



struct pci_host_bridge {

	struct list_head list;

	struct pci_bus *bus;		/* root bus */

};



/*

 * 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