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
  69         list_for_each_entry(dev, &parent->devices, bus_list) {
  70                 if ((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY)
  71                         continue;
  72
  73                 pci_configure_slot(dev);
  74         }
  75
  76         pci_bus_add_devices(parent);
  77
  78  out:
  79         pci_unlock_rescan_remove();
  80         return ret;
  81 }
  82
  83 int pciehp_unconfigure_device(struct slot *p_slot)
  84 {
  85         int rc = 0;
  86         u8 bctl = 0;
  87         u8 presence = 0;
  88         struct pci_dev *dev, *temp;
  89         struct pci_bus *parent = p_slot->ctrl->pcie->port->subordinate;
  90         u16 command;
  91         struct controller *ctrl = p_slot->ctrl;
  92
  93         ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:00\n",
  94                  __func__, pci_domain_nr(parent), parent->number);
  95         pciehp_get_adapter_status(p_slot, &presence);
  96
  97         pci_lock_rescan_remove();
  98
  99         /*
 100          * Stopping an SR-IOV PF device removes all the associated VFs,
 101          * which will update the bus->devices list and confuse the
 102          * iterator.  Therefore, iterate in reverse so we remove the VFs
 103          * first, then the PF.  We do the same in pci_stop_bus_device().
 104          */
 105         list_for_each_entry_safe_reverse(dev, temp, &parent->devices,
 106                                          bus_list) {
 107                 pci_dev_get(dev);
 108                 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE && presence) {
 109                         pci_read_config_byte(dev, PCI_BRIDGE_CONTROL, &bctl);
 110                         if (bctl & PCI_BRIDGE_CTL_VGA) {
 111                                 ctrl_err(ctrl,
 112                                          "Cannot remove display device %s\n",
 113                                          pci_name(dev));
 114                                 pci_dev_put(dev);
 115                                 rc = -EINVAL;
 116                                 break;
 117                         }
 118                 }
 119                 pci_stop_and_remove_bus_device(dev);
 120                 /*
 121                  * Ensure that no new Requests will be generated from
 122                  * the device.
 123                  */
 124                 if (presence) {
 125                         pci_read_config_word(dev, PCI_COMMAND, &command);
 126                         command &= ~(PCI_COMMAND_MASTER | PCI_COMMAND_SERR);
 127                         command |= PCI_COMMAND_INTX_DISABLE;
 128                         pci_write_config_word(dev, PCI_COMMAND, command);
 129                 }
 130                 pci_dev_put(dev);
 131         }
 132
 133         pci_unlock_rescan_remove();
 134         return rc;
 135 }