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 "
  50                          "at %04x:%02x:00, cannot hot-add\n", pci_name(dev),
  51                          pci_domain_nr(parent), parent->number);
  52                 pci_dev_put(dev);
  53                 ret = -EEXIST;
  54                 goto out;
  55         }
  56
  57         num = pci_scan_slot(parent, PCI_DEVFN(0, 0));
  58         if (num == 0) {
  59                 ctrl_err(ctrl, "No new device found\n");
  60                 ret = -ENODEV;
  61                 goto out;
  62         }
  63
  64         list_for_each_entry(dev, &parent->devices, bus_list)
  65                 if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
  66                                 (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS))
  67                         pci_hp_add_bridge(dev);
  68
  69         pci_assign_unassigned_bridge_resources(bridge);
  70
  71         list_for_each_entry(dev, &parent->devices, bus_list) {
  72                 if ((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY)
  73                         continue;
  74
  75                 pci_configure_slot(dev);
  76         }
  77
  78         pci_bus_add_devices(parent);
  79
  80  out:
  81         pci_unlock_rescan_remove();
  82         return ret;
  83 }
  84
  85 int pciehp_unconfigure_device(struct slot *p_slot)
  86 {
  87         int rc = 0;
  88         u8 bctl = 0;
  89         u8 presence = 0;
  90         struct pci_dev *dev, *temp;
  91         struct pci_bus *parent = p_slot->ctrl->pcie->port->subordinate;
  92         u16 command;
  93         struct controller *ctrl = p_slot->ctrl;
  94
  95         ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:00\n",
  96                  __func__, pci_domain_nr(parent), parent->number);
  97         pciehp_get_adapter_status(p_slot, &presence);
  98
  99         pci_lock_rescan_remove();
 100
 101         /*
 102          * Stopping an SR-IOV PF device removes all the associated VFs,
 103          * which will update the bus->devices list and confuse the
 104          * iterator.  Therefore, iterate in reverse so we remove the VFs
 105          * first, then the PF.  We do the same in pci_stop_bus_device().
 106          */
 107         list_for_each_entry_safe_reverse(dev, temp, &parent->devices,
 108                                          bus_list) {
 109                 pci_dev_get(dev);
 110                 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE && presence) {
 111                         pci_read_config_byte(dev, PCI_BRIDGE_CONTROL, &bctl);
 112                         if (bctl & PCI_BRIDGE_CTL_VGA) {
 113                                 ctrl_err(ctrl,
 114                                          "Cannot remove display device %s\n",
 115                                          pci_name(dev));
 116                                 pci_dev_put(dev);
 117                                 rc = -EINVAL;
 118                                 break;
 119                         }
 120                 }
 121                 pci_stop_and_remove_bus_device(dev);
 122                 /*
 123                  * Ensure that no new Requests will be generated from
 124                  * the device.
 125                  */
 126                 if (presence) {
 127                         pci_read_config_word(dev, PCI_COMMAND, &command);
 128                         command &= ~(PCI_COMMAND_MASTER | PCI_COMMAND_SERR);
 129                         command |= PCI_COMMAND_INTX_DISABLE;
 130                         pci_write_config_word(dev, PCI_COMMAND, command);
 131                 }
 132                 pci_dev_put(dev);
 133         }
 134
 135         pci_unlock_rescan_remove();
 136         return rc;
 137 }