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 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         pci_bus_size_bridges(dev->subordinate);
  57         pci_bus_assign_resources(parent);
  58         pci_enable_bridges(parent);
  59         pci_bus_add_devices(parent);
  60         return 0;
  61 }
  62
  63 int pciehp_configure_device(struct slot *p_slot)
  64 {
  65         struct pci_dev *dev;
  66         struct pci_bus *parent = p_slot->ctrl->pci_dev->subordinate;
  67         int num, fn;
  68
  69         dev = pci_find_slot(p_slot->bus, PCI_DEVFN(p_slot->device, 0));
  70         if (dev) {
  71                 err("Device %s already exists at %x:%x, cannot hot-add\n",
  72                                 pci_name(dev), p_slot->bus, p_slot->device);
  73                 return -EINVAL;
  74         }
  75
  76         num = pci_scan_slot(parent, PCI_DEVFN(p_slot->device, 0));
  77         if (num == 0) {
  78                 err("No new device found\n");
  79                 return -ENODEV;
  80         }
  81
  82         for (fn = 0; fn < 8; fn++) {
  83                 dev = pci_get_slot(parent, PCI_DEVFN(p_slot->device, fn));
  84                 if (!dev)
  85                         continue;
  86                 if ((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
  87                         err("Cannot hot-add display device %s\n",
  88                                         pci_name(dev));
  89                         continue;
  90                 }
  91                 if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
  92                                 (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)) {
  93                         pciehp_add_bridge(dev);
  94                 }
  95                 /* TBD: program firmware provided _HPP values */
  96                 /* program_fw_provided_values(dev); */
  97         }
  98
  99         pci_bus_assign_resources(parent);
 100         pci_bus_add_devices(parent);
 101         return 0;
 102 }
 103
 104 int pciehp_unconfigure_device(struct slot *p_slot)
 105 {
 106         int rc = 0;
 107         int j;
 108         u8 bctl = 0;
 109
 110         dbg("%s: bus/dev = %x/%x\n", __FUNCTION__, p_slot->bus,
 111                                 p_slot->device);
 112
 113         for (j=0; j<8 ; j++) {
 114                 struct pci_dev* temp = pci_find_slot(p_slot->bus,
 115                                 (p_slot->device << 3) | j);
 116                 if (!temp)
 117                         continue;
 118                 if ((temp->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
 119                         err("Cannot remove display device %s\n",
 120                                         pci_name(temp));
 121                         continue;
 122                 }
 123                 if (temp->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
 124                         pci_read_config_byte(temp, PCI_BRIDGE_CONTROL, &bctl);
 125                         if (bctl & PCI_BRIDGE_CTL_VGA) {
 126                                 err("Cannot remove display device %s\n",
 127                                                 pci_name(temp));
 128                                 continue;
 129                         }
 130                 }
 131                 pci_remove_bus_device(temp);
 132         }
 133         /*
 134          * Some PCI Express root ports require fixup after hot-plug operation.
 135          */
 136         if (pcie_mch_quirk)
 137                 pci_fixup_device(pci_fixup_final, p_slot->ctrl->pci_dev);
 138
 139         return rc;
 140 }
 141