linux-zen-server/arch/powerpc/kernel/pci-hotplug.c

150 lines
4.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Derived from "arch/powerpc/platforms/pseries/pci_dlpar.c"
*
* Copyright (C) 2003 Linda Xie <lxie@us.ibm.com>
* Copyright (C) 2005 International Business Machines
*
* Updates, 2005, John Rose <johnrose@austin.ibm.com>
* Updates, 2005, Linas Vepstas <linas@austin.ibm.com>
* Updates, 2013, Gavin Shan <shangw@linux.vnet.ibm.com>
*/
#include <linux/pci.h>
#include <linux/export.h>
#include <linux/of.h>
#include <asm/pci-bridge.h>
#include <asm/ppc-pci.h>
#include <asm/firmware.h>
#include <asm/eeh.h>
static struct pci_bus *find_bus_among_children(struct pci_bus *bus,
struct device_node *dn)
{
struct pci_bus *child = NULL;
struct pci_bus *tmp;
if (pci_bus_to_OF_node(bus) == dn)
return bus;
list_for_each_entry(tmp, &bus->children, node) {
child = find_bus_among_children(tmp, dn);
if (child)
break;
}
return child;
}
struct pci_bus *pci_find_bus_by_node(struct device_node *dn)
{
struct pci_dn *pdn = PCI_DN(dn);
if (!pdn || !pdn->phb || !pdn->phb->bus)
return NULL;
return find_bus_among_children(pdn->phb->bus, dn);
}
EXPORT_SYMBOL_GPL(pci_find_bus_by_node);
/**
* pcibios_release_device - release PCI device
* @dev: PCI device
*
* The function is called before releasing the indicated PCI device.
*/
void pcibios_release_device(struct pci_dev *dev)
{
struct pci_controller *phb = pci_bus_to_host(dev->bus);
struct pci_dn *pdn = pci_get_pdn(dev);
if (phb->controller_ops.release_device)
phb->controller_ops.release_device(dev);
/* free()ing the pci_dn has been deferred to us, do it now */
if (pdn && (pdn->flags & PCI_DN_FLAG_DEAD)) {
pci_dbg(dev, "freeing dead pdn\n");
kfree(pdn);
}
}
/**
* pci_hp_remove_devices - remove all devices under this bus
* @bus: the indicated PCI bus
*
* Remove all of the PCI devices under this bus both from the
* linux pci device tree, and from the powerpc EEH address cache.
*/
void pci_hp_remove_devices(struct pci_bus *bus)
{
struct pci_dev *dev, *tmp;
struct pci_bus *child_bus;
/* First go down child busses */
list_for_each_entry(child_bus, &bus->children, node)
pci_hp_remove_devices(child_bus);
pr_debug("PCI: Removing devices on bus %04x:%02x\n",
pci_domain_nr(bus), bus->number);
list_for_each_entry_safe_reverse(dev, tmp, &bus->devices, bus_list) {
pr_debug(" Removing %s...\n", pci_name(dev));
pci_stop_and_remove_bus_device(dev);
}
}
EXPORT_SYMBOL_GPL(pci_hp_remove_devices);
/**
* pci_hp_add_devices - adds new pci devices to bus
* @bus: the indicated PCI bus
*
* This routine will find and fixup new pci devices under
* the indicated bus. This routine presumes that there
* might already be some devices under this bridge, so
* it carefully tries to add only new devices. (And that
* is how this routine differs from other, similar pcibios
* routines.)
*/
void pci_hp_add_devices(struct pci_bus *bus)
{
int slotno, mode, max;
struct pci_dev *dev;
struct pci_controller *phb;
struct device_node *dn = pci_bus_to_OF_node(bus);
phb = pci_bus_to_host(bus);
mode = PCI_PROBE_NORMAL;
if (phb->controller_ops.probe_mode)
mode = phb->controller_ops.probe_mode(bus);
if (mode == PCI_PROBE_DEVTREE) {
/* use ofdt-based probe */
of_rescan_bus(dn, bus);
} else if (mode == PCI_PROBE_NORMAL &&
dn->child && PCI_DN(dn->child)) {
/*
* Use legacy probe. In the partial hotplug case, we
* probably have grandchildren devices unplugged. So
* we don't check the return value from pci_scan_slot() in
* order for fully rescan all the way down to pick them up.
* They can have been removed during partial hotplug.
*/
slotno = PCI_SLOT(PCI_DN(dn->child)->devfn);
pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
max = bus->busn_res.start;
/*
* Scan bridges that are already configured. We don't touch
* them unless they are misconfigured (which will be done in
* the second scan below).
*/
for_each_pci_bridge(dev, bus)
max = pci_scan_bridge(bus, dev, max, 0);
/* Scan bridges that need to be reconfigured */
for_each_pci_bridge(dev, bus)
max = pci_scan_bridge(bus, dev, max, 1);
}
pcibios_finish_adding_to_bus(bus);
}
EXPORT_SYMBOL_GPL(pci_hp_add_devices);