kernel/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                 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
  76 int 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 }