LXR linux/drivers/pci/hotplug/pciehp

   1/*
   2 * PCI Express Hot Plug Controller Driver
   3 *
   4 * Copyright (C) 1995,2001 Compaq Computer Corporation
   5 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
   6 * Copyright (C) 2001 IBM Corp.
   7 * Copyright (C) 2003-2004 Intel Corporation
   8 *
   9 * All rights reserved.
  10 *
  11 * This program is free software; you can redistribute it and/or modify
  12 * it under the terms of the GNU General Public License as published by
  13 * the Free Software Foundation; either version 2 of the License, or (at
  14 * your option) any later version.
  15 *
  16 * This program is distributed in the hope that it will be useful, but
  17 * WITHOUT ANY WARRANTY; without even the implied warranty of
  18 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  19 * NON INFRINGEMENT.  See the GNU General Public License for more
  20 * details.
  21 *
  22 * You should have received a copy of the GNU General Public License
  23 * along with this program; if not, write to the Free Software
  24 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  25 *
  26 * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
  27 *
  28 */
  29
  30#include <linux/module.h>
  31#include <linux/kernel.h>
  32#include <linux/types.h>
  33#include <linux/pci.h>
  34#include "../pci.h"
  35#include "pciehp.h"
  36
  37int pciehp_configure_device(struct slot *p_slot)
  38{
  39        struct pci_dev *dev;
  40        struct pci_dev *bridge = p_slot->ctrl->pcie->port;
  41        struct pci_bus *parent = bridge->subordinate;
  42        int num, ret = 0;
  43        struct controller *ctrl = p_slot->ctrl;
  44
  45        pci_lock_rescan_remove();
  46
  47        dev = pci_get_slot(parent, PCI_DEVFN(0, 0));
  48        if (dev) {
  49                ctrl_err(ctrl, "Device %s already exists at %04x:%02x:00, cannot hot-add\n",
  50                         pci_name(dev), pci_domain_nr(parent), parent->number);
  51                pci_dev_put(dev);
  52                ret = -EEXIST;
  53                goto out;
  54        }
  55
  56        num = pci_scan_slot(parent, PCI_DEVFN(0, 0));
  57        if (num == 0) {
  58                ctrl_err(ctrl, "No new device found\n");
  59                ret = -ENODEV;
  60                goto out;
  61        }
  62
  63        list_for_each_entry(dev, &parent->devices, bus_list)
  64                if (pci_is_bridge(dev))
  65                        pci_hp_add_bridge(dev);
  66
  67        pci_assign_unassigned_bridge_resources(bridge);
  68        pcie_bus_configure_settings(parent);
  69        pci_bus_add_devices(parent);
  70
  71 out:
  72        pci_unlock_rescan_remove();
  73        return ret;
  74}
  75
  76int pciehp_unconfigure_device(struct slot *p_slot)
  77{
  78        int rc = 0;
  79        u8 bctl = 0;
  80        u8 presence = 0;
  81        struct pci_dev *dev, *temp;
  82        struct pci_bus *parent = p_slot->ctrl->pcie->port->subordinate;
  83        u16 command;
  84        struct controller *ctrl = p_slot->ctrl;
  85
  86        ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:00\n",
  87                 __func__, pci_domain_nr(parent), parent->number);
  88        pciehp_get_adapter_status(p_slot, &presence);
  89
  90        pci_lock_rescan_remove();
  91
  92        /*
  93         * Stopping an SR-IOV PF device removes all the associated VFs,
  94         * which will update the bus->devices list and confuse the
  95         * iterator.  Therefore, iterate in reverse so we remove the VFs
  96         * first, then the PF.  We do the same in pci_stop_bus_device().
  97         */
  98        list_for_each_entry_safe_reverse(dev, temp, &parent->devices,
  99                                         bus_list) {
 100                pci_dev_get(dev);
 101                if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE && presence) {
 102                        pci_read_config_byte(dev, PCI_BRIDGE_CONTROL, &bctl);
 103                        if (bctl & PCI_BRIDGE_CTL_VGA) {
 104                                ctrl_err(ctrl,
 105                                         "Cannot remove display device %s\n",
 106                                         pci_name(dev));
 107                                pci_dev_put(dev);
 108                                rc = -EINVAL;
 109                                break;
 110                        }
 111                }
 112                pci_stop_and_remove_bus_device(dev);
 113                /*
 114                 * Ensure that no new Requests will be generated from
 115                 * the device.
 116                 */
 117                if (presence) {
 118                        pci_read_config_word(dev, PCI_COMMAND, &command);
 119                        command &= ~(PCI_COMMAND_MASTER | PCI_COMMAND_SERR);
 120                        command |= PCI_COMMAND_INTX_DISABLE;
 121                        pci_write_config_word(dev, PCI_COMMAND, command);
 122                }
 123                pci_dev_put(dev);
 124        }
 125
 126        pci_unlock_rescan_remove();
 127        return rc;
 128}
 129