kernel-ark/drivers/pci/bus.c
Zhang, Yanmin 70298c6e6c PCI AER: support Multiple Error Received and no error source id
Based on PCI Express AER specs, a root port might receive multiple
TLP errors while it could only save a correctable error source id
and an uncorrectable error source id at the same time. In addition,
some root port hardware might be unable to provide a correct source
id, i.e., the source id, or the bus id part of the source id provided
by root port might be equal to 0.

The patchset implements the support in kernel by searching the device
tree under the root port.

Patch 1 changes parameter cb of function pci_walk_bus to return a value.
When cb return non-zero, pci_walk_bus stops more searching on the
device tree.

Reviewed-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Zhang Yanmin <yanmin_zhang@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-16 14:30:13 -07:00

256 lines
6.2 KiB
C

/*
* drivers/pci/bus.c
*
* From setup-res.c, by:
* Dave Rusling (david.rusling@reo.mts.dec.com)
* David Mosberger (davidm@cs.arizona.edu)
* David Miller (davem@redhat.com)
* Ivan Kokshaysky (ink@jurassic.park.msu.ru)
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/proc_fs.h>
#include <linux/init.h>
#include "pci.h"
/**
* pci_bus_alloc_resource - allocate a resource from a parent bus
* @bus: PCI bus
* @res: resource to allocate
* @size: size of resource to allocate
* @align: alignment of resource to allocate
* @min: minimum /proc/iomem address to allocate
* @type_mask: IORESOURCE_* type flags
* @alignf: resource alignment function
* @alignf_data: data argument for resource alignment function
*
* Given the PCI bus a device resides on, the size, minimum address,
* alignment and type, try to find an acceptable resource allocation
* for a specific device resource.
*/
int
pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
resource_size_t size, resource_size_t align,
resource_size_t min, unsigned int type_mask,
void (*alignf)(void *, struct resource *, resource_size_t,
resource_size_t),
void *alignf_data)
{
int i, ret = -ENOMEM;
resource_size_t max = -1;
type_mask |= IORESOURCE_IO | IORESOURCE_MEM;
/* don't allocate too high if the pref mem doesn't support 64bit*/
if (!(res->flags & IORESOURCE_MEM_64))
max = PCIBIOS_MAX_MEM_32;
for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
struct resource *r = bus->resource[i];
if (!r)
continue;
/* type_mask must match */
if ((res->flags ^ r->flags) & type_mask)
continue;
/* We cannot allocate a non-prefetching resource
from a pre-fetching area */
if ((r->flags & IORESOURCE_PREFETCH) &&
!(res->flags & IORESOURCE_PREFETCH))
continue;
/* Ok, try it out.. */
ret = allocate_resource(r, res, size,
r->start ? : min,
max, align,
alignf, alignf_data);
if (ret == 0)
break;
}
return ret;
}
/**
* pci_bus_add_device - add a single device
* @dev: device to add
*
* This adds a single pci device to the global
* device list and adds sysfs and procfs entries
*/
int pci_bus_add_device(struct pci_dev *dev)
{
int retval;
retval = device_add(&dev->dev);
if (retval)
return retval;
dev->is_added = 1;
pci_proc_attach_device(dev);
pci_create_sysfs_dev_files(dev);
return 0;
}
/**
* pci_bus_add_child - add a child bus
* @bus: bus to add
*
* This adds sysfs entries for a single bus
*/
int pci_bus_add_child(struct pci_bus *bus)
{
int retval;
if (bus->bridge)
bus->dev.parent = bus->bridge;
retval = device_register(&bus->dev);
if (retval)
return retval;
bus->is_added = 1;
retval = device_create_file(&bus->dev, &dev_attr_cpuaffinity);
if (retval)
return retval;
retval = device_create_file(&bus->dev, &dev_attr_cpulistaffinity);
/* Create legacy_io and legacy_mem files for this bus */
pci_create_legacy_files(bus);
return retval;
}
/**
* pci_bus_add_devices - insert newly discovered PCI devices
* @bus: bus to check for new devices
*
* Add newly discovered PCI devices (which are on the bus->devices
* list) to the global PCI device list, add the sysfs and procfs
* entries. Where a bridge is found, add the discovered bus to
* the parents list of child buses, and recurse (breadth-first
* to be compatible with 2.4)
*
* Call hotplug for each new devices.
*/
void pci_bus_add_devices(const struct pci_bus *bus)
{
struct pci_dev *dev;
struct pci_bus *child;
int retval;
list_for_each_entry(dev, &bus->devices, bus_list) {
/* Skip already-added devices */
if (dev->is_added)
continue;
retval = pci_bus_add_device(dev);
if (retval)
dev_err(&dev->dev, "Error adding device, continuing\n");
}
list_for_each_entry(dev, &bus->devices, bus_list) {
BUG_ON(!dev->is_added);
child = dev->subordinate;
/*
* If there is an unattached subordinate bus, attach
* it and then scan for unattached PCI devices.
*/
if (!child)
continue;
if (list_empty(&child->node)) {
down_write(&pci_bus_sem);
list_add_tail(&child->node, &dev->bus->children);
up_write(&pci_bus_sem);
}
pci_bus_add_devices(child);
/*
* register the bus with sysfs as the parent is now
* properly registered.
*/
if (child->is_added)
continue;
retval = pci_bus_add_child(child);
if (retval)
dev_err(&dev->dev, "Error adding bus, continuing\n");
}
}
void pci_enable_bridges(struct pci_bus *bus)
{
struct pci_dev *dev;
int retval;
list_for_each_entry(dev, &bus->devices, bus_list) {
if (dev->subordinate) {
if (!pci_is_enabled(dev)) {
retval = pci_enable_device(dev);
pci_set_master(dev);
}
pci_enable_bridges(dev->subordinate);
}
}
}
/** pci_walk_bus - walk devices on/under bus, calling callback.
* @top bus whose devices should be walked
* @cb callback to be called for each device found
* @userdata arbitrary pointer to be passed to callback.
*
* Walk the given bus, including any bridged devices
* on buses under this bus. Call the provided callback
* on each device found.
*
* We check the return of @cb each time. If it returns anything
* other than 0, we break out.
*
*/
void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
void *userdata)
{
struct pci_dev *dev;
struct pci_bus *bus;
struct list_head *next;
int retval;
bus = top;
down_read(&pci_bus_sem);
next = top->devices.next;
for (;;) {
if (next == &bus->devices) {
/* end of this bus, go up or finish */
if (bus == top)
break;
next = bus->self->bus_list.next;
bus = bus->self->bus;
continue;
}
dev = list_entry(next, struct pci_dev, bus_list);
if (dev->subordinate) {
/* this is a pci-pci bridge, do its devices next */
next = dev->subordinate->devices.next;
bus = dev->subordinate;
} else
next = dev->bus_list.next;
/* Run device routines with the device locked */
down(&dev->dev.sem);
retval = cb(dev, userdata);
up(&dev->dev.sem);
if (retval)
break;
}
up_read(&pci_bus_sem);
}
EXPORT_SYMBOL(pci_bus_alloc_resource);
EXPORT_SYMBOL_GPL(pci_bus_add_device);
EXPORT_SYMBOL(pci_bus_add_devices);
EXPORT_SYMBOL(pci_enable_bridges);