360 lines
11 KiB
C
360 lines
11 KiB
C
/*
|
|
* PCI searching functions.
|
|
*
|
|
* Copyright (C) 1993 -- 1997 Drew Eckhardt, Frederic Potter,
|
|
* David Mosberger-Tang
|
|
* Copyright (C) 1997 -- 2000 Martin Mares <mj@ucw.cz>
|
|
* Copyright (C) 2003 -- 2004 Greg Kroah-Hartman <greg@kroah.com>
|
|
*/
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/pci.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/module.h>
|
|
#include <linux/interrupt.h>
|
|
#include "pci.h"
|
|
|
|
DECLARE_RWSEM(pci_bus_sem);
|
|
/*
|
|
* find the upstream PCIe-to-PCI bridge of a PCI device
|
|
* if the device is PCIE, return NULL
|
|
* if the device isn't connected to a PCIe bridge (that is its parent is a
|
|
* legacy PCI bridge and the bridge is directly connected to bus 0), return its
|
|
* parent
|
|
*/
|
|
struct pci_dev *
|
|
pci_find_upstream_pcie_bridge(struct pci_dev *pdev)
|
|
{
|
|
struct pci_dev *tmp = NULL;
|
|
|
|
if (pci_is_pcie(pdev))
|
|
return NULL;
|
|
while (1) {
|
|
if (pci_is_root_bus(pdev->bus))
|
|
break;
|
|
pdev = pdev->bus->self;
|
|
/* a p2p bridge */
|
|
if (!pci_is_pcie(pdev)) {
|
|
tmp = pdev;
|
|
continue;
|
|
}
|
|
/* PCI device should connect to a PCIe bridge */
|
|
if (pdev->pcie_type != PCI_EXP_TYPE_PCI_BRIDGE) {
|
|
/* Busted hardware? */
|
|
WARN_ON_ONCE(1);
|
|
return NULL;
|
|
}
|
|
return pdev;
|
|
}
|
|
|
|
return tmp;
|
|
}
|
|
|
|
static struct pci_bus *pci_do_find_bus(struct pci_bus *bus, unsigned char busnr)
|
|
{
|
|
struct pci_bus* child;
|
|
struct list_head *tmp;
|
|
|
|
if(bus->number == busnr)
|
|
return bus;
|
|
|
|
list_for_each(tmp, &bus->children) {
|
|
child = pci_do_find_bus(pci_bus_b(tmp), busnr);
|
|
if(child)
|
|
return child;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* pci_find_bus - locate PCI bus from a given domain and bus number
|
|
* @domain: number of PCI domain to search
|
|
* @busnr: number of desired PCI bus
|
|
*
|
|
* Given a PCI bus number and domain number, the desired PCI bus is located
|
|
* in the global list of PCI buses. If the bus is found, a pointer to its
|
|
* data structure is returned. If no bus is found, %NULL is returned.
|
|
*/
|
|
struct pci_bus * pci_find_bus(int domain, int busnr)
|
|
{
|
|
struct pci_bus *bus = NULL;
|
|
struct pci_bus *tmp_bus;
|
|
|
|
while ((bus = pci_find_next_bus(bus)) != NULL) {
|
|
if (pci_domain_nr(bus) != domain)
|
|
continue;
|
|
tmp_bus = pci_do_find_bus(bus, busnr);
|
|
if (tmp_bus)
|
|
return tmp_bus;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* pci_find_next_bus - begin or continue searching for a PCI bus
|
|
* @from: Previous PCI bus found, or %NULL for new search.
|
|
*
|
|
* Iterates through the list of known PCI busses. A new search is
|
|
* initiated by passing %NULL as the @from argument. Otherwise if
|
|
* @from is not %NULL, searches continue from next device on the
|
|
* global list.
|
|
*/
|
|
struct pci_bus *
|
|
pci_find_next_bus(const struct pci_bus *from)
|
|
{
|
|
struct list_head *n;
|
|
struct pci_bus *b = NULL;
|
|
|
|
WARN_ON(in_interrupt());
|
|
down_read(&pci_bus_sem);
|
|
n = from ? from->node.next : pci_root_buses.next;
|
|
if (n != &pci_root_buses)
|
|
b = pci_bus_b(n);
|
|
up_read(&pci_bus_sem);
|
|
return b;
|
|
}
|
|
|
|
/**
|
|
* pci_get_slot - locate PCI device for a given PCI slot
|
|
* @bus: PCI bus on which desired PCI device resides
|
|
* @devfn: encodes number of PCI slot in which the desired PCI
|
|
* device resides and the logical device number within that slot
|
|
* in case of multi-function devices.
|
|
*
|
|
* Given a PCI bus and slot/function number, the desired PCI device
|
|
* is located in the list of PCI devices.
|
|
* If the device is found, its reference count is increased and this
|
|
* function returns a pointer to its data structure. The caller must
|
|
* decrement the reference count by calling pci_dev_put().
|
|
* If no device is found, %NULL is returned.
|
|
*/
|
|
struct pci_dev * pci_get_slot(struct pci_bus *bus, unsigned int devfn)
|
|
{
|
|
struct list_head *tmp;
|
|
struct pci_dev *dev;
|
|
|
|
WARN_ON(in_interrupt());
|
|
down_read(&pci_bus_sem);
|
|
|
|
list_for_each(tmp, &bus->devices) {
|
|
dev = pci_dev_b(tmp);
|
|
if (dev->devfn == devfn)
|
|
goto out;
|
|
}
|
|
|
|
dev = NULL;
|
|
out:
|
|
pci_dev_get(dev);
|
|
up_read(&pci_bus_sem);
|
|
return dev;
|
|
}
|
|
|
|
/**
|
|
* pci_get_domain_bus_and_slot - locate PCI device for a given PCI domain (segment), bus, and slot
|
|
* @domain: PCI domain/segment on which the PCI device resides.
|
|
* @bus: PCI bus on which desired PCI device resides
|
|
* @devfn: encodes number of PCI slot in which the desired PCI device
|
|
* resides and the logical device number within that slot in case of
|
|
* multi-function devices.
|
|
*
|
|
* Given a PCI domain, bus, and slot/function number, the desired PCI
|
|
* device is located in the list of PCI devices. If the device is
|
|
* found, its reference count is increased and this function returns a
|
|
* pointer to its data structure. The caller must decrement the
|
|
* reference count by calling pci_dev_put(). If no device is found,
|
|
* %NULL is returned.
|
|
*/
|
|
struct pci_dev *pci_get_domain_bus_and_slot(int domain, unsigned int bus,
|
|
unsigned int devfn)
|
|
{
|
|
struct pci_dev *dev = NULL;
|
|
|
|
while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
|
|
if (pci_domain_nr(dev->bus) == domain &&
|
|
(dev->bus->number == bus && dev->devfn == devfn))
|
|
return dev;
|
|
}
|
|
return NULL;
|
|
}
|
|
EXPORT_SYMBOL(pci_get_domain_bus_and_slot);
|
|
|
|
static int match_pci_dev_by_id(struct device *dev, void *data)
|
|
{
|
|
struct pci_dev *pdev = to_pci_dev(dev);
|
|
struct pci_device_id *id = data;
|
|
|
|
if (pci_match_one_device(id, pdev))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* pci_get_dev_by_id - begin or continue searching for a PCI device by id
|
|
* @id: pointer to struct pci_device_id to match for the device
|
|
* @from: Previous PCI device found in search, or %NULL for new search.
|
|
*
|
|
* Iterates through the list of known PCI devices. If a PCI device is found
|
|
* with a matching id a pointer to its device structure is returned, and the
|
|
* reference count to the device is incremented. Otherwise, %NULL is returned.
|
|
* A new search is initiated by passing %NULL as the @from argument. Otherwise
|
|
* if @from is not %NULL, searches continue from next device on the global
|
|
* list. The reference count for @from is always decremented if it is not
|
|
* %NULL.
|
|
*
|
|
* This is an internal function for use by the other search functions in
|
|
* this file.
|
|
*/
|
|
static struct pci_dev *pci_get_dev_by_id(const struct pci_device_id *id,
|
|
struct pci_dev *from)
|
|
{
|
|
struct device *dev;
|
|
struct device *dev_start = NULL;
|
|
struct pci_dev *pdev = NULL;
|
|
|
|
WARN_ON(in_interrupt());
|
|
if (from)
|
|
dev_start = &from->dev;
|
|
dev = bus_find_device(&pci_bus_type, dev_start, (void *)id,
|
|
match_pci_dev_by_id);
|
|
if (dev)
|
|
pdev = to_pci_dev(dev);
|
|
if (from)
|
|
pci_dev_put(from);
|
|
return pdev;
|
|
}
|
|
|
|
/**
|
|
* pci_get_subsys - begin or continue searching for a PCI device by vendor/subvendor/device/subdevice id
|
|
* @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
|
|
* @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
|
|
* @ss_vendor: PCI subsystem vendor id to match, or %PCI_ANY_ID to match all vendor ids
|
|
* @ss_device: PCI subsystem device id to match, or %PCI_ANY_ID to match all device ids
|
|
* @from: Previous PCI device found in search, or %NULL for new search.
|
|
*
|
|
* Iterates through the list of known PCI devices. If a PCI device is found
|
|
* with a matching @vendor, @device, @ss_vendor and @ss_device, a pointer to its
|
|
* device structure is returned, and the reference count to the device is
|
|
* incremented. Otherwise, %NULL is returned. A new search is initiated by
|
|
* passing %NULL as the @from argument. Otherwise if @from is not %NULL,
|
|
* searches continue from next device on the global list.
|
|
* The reference count for @from is always decremented if it is not %NULL.
|
|
*/
|
|
struct pci_dev *pci_get_subsys(unsigned int vendor, unsigned int device,
|
|
unsigned int ss_vendor, unsigned int ss_device,
|
|
struct pci_dev *from)
|
|
{
|
|
struct pci_dev *pdev;
|
|
struct pci_device_id *id;
|
|
|
|
/*
|
|
* pci_find_subsys() can be called on the ide_setup() path,
|
|
* super-early in boot. But the down_read() will enable local
|
|
* interrupts, which can cause some machines to crash. So here we
|
|
* detect and flag that situation and bail out early.
|
|
*/
|
|
if (unlikely(no_pci_devices()))
|
|
return NULL;
|
|
|
|
id = kzalloc(sizeof(*id), GFP_KERNEL);
|
|
if (!id)
|
|
return NULL;
|
|
id->vendor = vendor;
|
|
id->device = device;
|
|
id->subvendor = ss_vendor;
|
|
id->subdevice = ss_device;
|
|
|
|
pdev = pci_get_dev_by_id(id, from);
|
|
kfree(id);
|
|
|
|
return pdev;
|
|
}
|
|
|
|
/**
|
|
* pci_get_device - begin or continue searching for a PCI device by vendor/device id
|
|
* @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
|
|
* @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
|
|
* @from: Previous PCI device found in search, or %NULL for new search.
|
|
*
|
|
* Iterates through the list of known PCI devices. If a PCI device is
|
|
* found with a matching @vendor and @device, the reference count to the
|
|
* device is incremented and a pointer to its device structure is returned.
|
|
* Otherwise, %NULL is returned. A new search is initiated by passing %NULL
|
|
* as the @from argument. Otherwise if @from is not %NULL, searches continue
|
|
* from next device on the global list. The reference count for @from is
|
|
* always decremented if it is not %NULL.
|
|
*/
|
|
struct pci_dev *
|
|
pci_get_device(unsigned int vendor, unsigned int device, struct pci_dev *from)
|
|
{
|
|
return pci_get_subsys(vendor, device, PCI_ANY_ID, PCI_ANY_ID, from);
|
|
}
|
|
|
|
/**
|
|
* pci_get_class - begin or continue searching for a PCI device by class
|
|
* @class: search for a PCI device with this class designation
|
|
* @from: Previous PCI device found in search, or %NULL for new search.
|
|
*
|
|
* Iterates through the list of known PCI devices. If a PCI device is
|
|
* found with a matching @class, the reference count to the device is
|
|
* incremented and a pointer to its device structure is returned.
|
|
* Otherwise, %NULL is returned.
|
|
* A new search is initiated by passing %NULL as the @from argument.
|
|
* Otherwise if @from is not %NULL, searches continue from next device
|
|
* on the global list. The reference count for @from is always decremented
|
|
* if it is not %NULL.
|
|
*/
|
|
struct pci_dev *pci_get_class(unsigned int class, struct pci_dev *from)
|
|
{
|
|
struct pci_dev *dev;
|
|
struct pci_device_id *id;
|
|
|
|
id = kzalloc(sizeof(*id), GFP_KERNEL);
|
|
if (!id)
|
|
return NULL;
|
|
id->vendor = id->device = id->subvendor = id->subdevice = PCI_ANY_ID;
|
|
id->class_mask = PCI_ANY_ID;
|
|
id->class = class;
|
|
|
|
dev = pci_get_dev_by_id(id, from);
|
|
kfree(id);
|
|
return dev;
|
|
}
|
|
|
|
/**
|
|
* pci_dev_present - Returns 1 if device matching the device list is present, 0 if not.
|
|
* @ids: A pointer to a null terminated list of struct pci_device_id structures
|
|
* that describe the type of PCI device the caller is trying to find.
|
|
*
|
|
* Obvious fact: You do not have a reference to any device that might be found
|
|
* by this function, so if that device is removed from the system right after
|
|
* this function is finished, the value will be stale. Use this function to
|
|
* find devices that are usually built into a system, or for a general hint as
|
|
* to if another device happens to be present at this specific moment in time.
|
|
*/
|
|
int pci_dev_present(const struct pci_device_id *ids)
|
|
{
|
|
struct pci_dev *found = NULL;
|
|
|
|
WARN_ON(in_interrupt());
|
|
while (ids->vendor || ids->subvendor || ids->class_mask) {
|
|
found = pci_get_dev_by_id(ids, NULL);
|
|
if (found)
|
|
goto exit;
|
|
ids++;
|
|
}
|
|
exit:
|
|
if (found)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(pci_dev_present);
|
|
|
|
/* For boot time work */
|
|
EXPORT_SYMBOL(pci_find_bus);
|
|
EXPORT_SYMBOL(pci_find_next_bus);
|
|
/* For everyone */
|
|
EXPORT_SYMBOL(pci_get_device);
|
|
EXPORT_SYMBOL(pci_get_subsys);
|
|
EXPORT_SYMBOL(pci_get_slot);
|
|
EXPORT_SYMBOL(pci_get_class);
|