linux/drivers/pci/hotplug/pciehp_pci.c
Yijing Wang ba518e3c17 PCI: pciehp: Iterate over all devices in slot, not functions 0-7
Currently, we enumerate devices in a slot with pci_scan_slot(), then
iterate through all the devices we found by looking for functions 0-7.  But
that's wrong for ARI devices, which may have function numbers up to 255.

This means that when we hot-add an ARI device, pciehp only initializes
functions 0-7, and other functions don't work correctly.  Additionally, if
we hot-remove the device, pciehp only removes functions 0-7, leaving stale
pci_dev structures for any other functions.

This patch fixes the problem by iterating over devices in a slot by using
the upstream bridge's "bus->devices" list instead.

[bhelgaas: changelog]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-01-25 09:21:10 -07:00

124 lines
3.4 KiB
C

/*
* PCI Express Hot Plug Controller Driver
*
* Copyright (C) 1995,2001 Compaq Computer Corporation
* Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
* Copyright (C) 2001 IBM Corp.
* Copyright (C) 2003-2004 Intel Corporation
*
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
*
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/pci.h>
#include "../pci.h"
#include "pciehp.h"
int pciehp_configure_device(struct slot *p_slot)
{
struct pci_dev *dev;
struct pci_dev *bridge = p_slot->ctrl->pcie->port;
struct pci_bus *parent = bridge->subordinate;
int num;
struct controller *ctrl = p_slot->ctrl;
dev = pci_get_slot(parent, PCI_DEVFN(0, 0));
if (dev) {
ctrl_err(ctrl, "Device %s already exists "
"at %04x:%02x:00, cannot hot-add\n", pci_name(dev),
pci_domain_nr(parent), parent->number);
pci_dev_put(dev);
return -EINVAL;
}
num = pci_scan_slot(parent, PCI_DEVFN(0, 0));
if (num == 0) {
ctrl_err(ctrl, "No new device found\n");
return -ENODEV;
}
list_for_each_entry(dev, &parent->devices, bus_list)
if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
(dev->hdr_type == PCI_HEADER_TYPE_CARDBUS))
pci_hp_add_bridge(dev);
pci_assign_unassigned_bridge_resources(bridge);
list_for_each_entry(dev, &parent->devices, bus_list) {
if ((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY)
continue;
pci_configure_slot(dev);
}
pci_bus_add_devices(parent);
return 0;
}
int pciehp_unconfigure_device(struct slot *p_slot)
{
int ret, rc = 0;
u8 bctl = 0;
u8 presence = 0;
struct pci_dev *dev, *temp;
struct pci_bus *parent = p_slot->ctrl->pcie->port->subordinate;
u16 command;
struct controller *ctrl = p_slot->ctrl;
ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:00\n",
__func__, pci_domain_nr(parent), parent->number);
ret = pciehp_get_adapter_status(p_slot, &presence);
if (ret)
presence = 0;
list_for_each_entry_safe(dev, temp, &parent->devices, bus_list) {
pci_dev_get(dev);
if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE && presence) {
pci_read_config_byte(dev, PCI_BRIDGE_CONTROL, &bctl);
if (bctl & PCI_BRIDGE_CTL_VGA) {
ctrl_err(ctrl,
"Cannot remove display device %s\n",
pci_name(dev));
pci_dev_put(dev);
rc = -EINVAL;
break;
}
}
pci_stop_and_remove_bus_device(dev);
/*
* Ensure that no new Requests will be generated from
* the device.
*/
if (presence) {
pci_read_config_word(dev, PCI_COMMAND, &command);
command &= ~(PCI_COMMAND_MASTER | PCI_COMMAND_SERR);
command |= PCI_COMMAND_INTX_DISABLE;
pci_write_config_word(dev, PCI_COMMAND, command);
}
pci_dev_put(dev);
}
return rc;
}