drivers/pci/hotplug/pciehp_pci.c

   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
  37 int 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                 /*
  50                  * The device is already there. Either configured by the
  51                  * boot firmware or a previous hotplug event.
  52                  */
  53                 ctrl_dbg(ctrl, "Device %s already exists at %04x:%02x:00, skipping hot-add\n",
  54                          pci_name(dev), pci_domain_nr(parent), parent->number);
  55                 pci_dev_put(dev);
  56                 ret = -EEXIST;
  57                 goto out;
  58         }
  59
  60         num = pci_scan_slot(parent, PCI_DEVFN(0, 0));
  61         if (num == 0) {
  62                 ctrl_err(ctrl, "No new device found\n");
  63                 ret = -ENODEV;
  64                 goto out;
  65         }
  66
  67         for_each_pci_bridge(dev, parent)
  68                 pci_hp_add_bridge(dev);
  69
  70         pci_assign_unassigned_bridge_resources(bridge);
  71         pcie_bus_configure_settings(parent);
  72         pci_bus_add_devices(parent);
  73
  74  out:
  75         pci_unlock_rescan_remove();
  76         return ret;
  77 }
  78
  79 int pciehp_unconfigure_device(struct slot *p_slot)
  80 {
  81         int rc = 0;
  82         u8 presence = 0;
  83         struct pci_dev *dev, *temp;
  84         struct pci_bus *parent = p_slot->ctrl->pcie->port->subordinate;
  85         u16 command;
  86         struct controller *ctrl = p_slot->ctrl;
  87
  88         ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:00\n",
  89                  __func__, pci_domain_nr(parent), parent->number);
  90         pciehp_get_adapter_status(p_slot, &presence);
  91
  92         pci_lock_rescan_remove();
  93
  94         /*
  95          * Stopping an SR-IOV PF device removes all the associated VFs,
  96          * which will update the bus->devices list and confuse the
  97          * iterator.  Therefore, iterate in reverse so we remove the VFs
  98          * first, then the PF.  We do the same in pci_stop_bus_device().
  99          */
 100         list_for_each_entry_safe_reverse(dev, temp, &parent->devices,
 101                                          bus_list) {
 102                 pci_dev_get(dev);
 103                 if (!presence) {
 104                         pci_dev_set_disconnected(dev, NULL);
 105                         if (pci_has_subordinate(dev))
 106                                 pci_walk_bus(dev->subordinate,
 107                                              pci_dev_set_disconnected, NULL);
 108                 }
 109                 pci_stop_and_remove_bus_device(dev);
 110                 /*
 111                  * Ensure that no new Requests will be generated from
 112                  * the device.
 113                  */
 114                 if (presence) {
 115                         pci_read_config_word(dev, PCI_COMMAND, &command);
 116                         command &= ~(PCI_COMMAND_MASTER | PCI_COMMAND_SERR);
 117                         command |= PCI_COMMAND_INTX_DISABLE;
 118                         pci_write_config_word(dev, PCI_COMMAND, command);
 119                 }
 120                 pci_dev_put(dev);
 121         }
 122
 123         pci_unlock_rescan_remove();
 124         return rc;
 125 }