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 static int __ref pciehp_add_bridge(struct pci_dev *dev)
  38 {
  39         struct pci_bus *parent = dev->bus;
  40         int pass, busnr, start = parent->secondary;
  41         int end = parent->subordinate;
  42
  43         for (busnr = start; busnr <= end; busnr++) {
  44                 if (!pci_find_bus(pci_domain_nr(parent), busnr))
  45                         break;
  46         }
  47         if (busnr-- > end) {
  48                 err("No bus number available for hot-added bridge %s\n",
  49                                 pci_name(dev));
  50                 return -1;
  51         }
  52         for (pass = 0; pass < 2; pass++)
  53                 busnr = pci_scan_bridge(parent, dev, busnr, pass);
  54         if (!dev->subordinate)
  55                 return -1;
  56
  57         return 0;
  58 }
  59
  60 int pciehp_configure_device(struct slot *p_slot)
  61 {
  62         struct pci_dev *dev;
  63         struct pci_dev *bridge = p_slot->ctrl->pcie->port;
  64         struct pci_bus *parent = bridge->subordinate;
  65         int num, fn;
  66         struct controller *ctrl = p_slot->ctrl;
  67
  68         dev = pci_get_slot(parent, PCI_DEVFN(0, 0));
  69         if (dev) {
  70                 ctrl_err(ctrl, "Device %s already exists "
  71                          "at %04x:%02x:00, cannot hot-add\n", pci_name(dev),
  72                          pci_domain_nr(parent), parent->number);
  73                 pci_dev_put(dev);
  74                 return -EINVAL;
  75         }
  76
  77         num = pci_scan_slot(parent, PCI_DEVFN(0, 0));
  78         if (num == 0) {
  79                 ctrl_err(ctrl, "No new device found\n");
  80                 return -ENODEV;
  81         }
  82
  83         for (fn = 0; fn < 8; fn++) {
  84                 dev = pci_get_slot(parent, PCI_DEVFN(0, fn));
  85                 if (!dev)
  86                         continue;
  87                 if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
  88                                 (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)) {
  89                         pciehp_add_bridge(dev);
  90                 }
  91                 pci_dev_put(dev);
  92         }
  93
  94         pci_assign_unassigned_bridge_resources(bridge);
  95
  96         for (fn = 0; fn < 8; fn++) {
  97                 dev = pci_get_slot(parent, PCI_DEVFN(0, fn));
  98                 if (!dev)
  99                         continue;
 100                 if ((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
 101                         pci_dev_put(dev);
 102                         continue;
 103                 }
 104                 pci_configure_slot(dev);
 105                 pci_dev_put(dev);
 106         }
 107
 108         pci_bus_add_devices(parent);
 109
 110         return 0;
 111 }
 112
 113 int pciehp_unconfigure_device(struct slot *p_slot)
 114 {
 115         int ret, rc = 0;
 116         int j;
 117         u8 bctl = 0;
 118         u8 presence = 0;
 119         struct pci_bus *parent = p_slot->ctrl->pcie->port->subordinate;
 120         u16 command;
 121         struct controller *ctrl = p_slot->ctrl;
 122
 123         ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:00\n",
 124                  __func__, pci_domain_nr(parent), parent->number);
 125         ret = pciehp_get_adapter_status(p_slot, &presence);
 126         if (ret)
 127                 presence = 0;
 128
 129         for (j = 0; j < 8; j++) {
 130                 struct pci_dev *temp = pci_get_slot(parent, PCI_DEVFN(0, j));
 131                 if (!temp)
 132                         continue;
 133                 if (temp->hdr_type == PCI_HEADER_TYPE_BRIDGE && presence) {
 134                         pci_read_config_byte(temp, PCI_BRIDGE_CONTROL, &bctl);
 135                         if (bctl & PCI_BRIDGE_CTL_VGA) {
 136                                 ctrl_err(ctrl,
 137                                          "Cannot remove display device %s\n",
 138                                          pci_name(temp));
 139                                 pci_dev_put(temp);
 140                                 rc = EINVAL;
 141                                 break;
 142                         }
 143                 }
 144                 pci_remove_bus_device(temp);
 145                 /*
 146                  * Ensure that no new Requests will be generated from
 147                  * the device.
 148                  */
 149                 if (presence) {
 150                         pci_read_config_word(temp, PCI_COMMAND, &command);
 151                         command &= ~(PCI_COMMAND_MASTER | PCI_COMMAND_SERR);
 152                         command |= PCI_COMMAND_INTX_DISABLE;
 153                         pci_write_config_word(temp, PCI_COMMAND, command);
 154                 }
 155                 pci_dev_put(temp);
 156         }
 157
 158         return rc;
 159 }