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
  38 int pciehp_configure_device(struct slot *p_slot)
  39 {
  40         struct pci_dev *dev;
  41         struct pci_bus *parent = p_slot->ctrl->pci_dev->subordinate;
  42         int num, fn;
  43
  44         dev = pci_find_slot(p_slot->bus, PCI_DEVFN(p_slot->device, 0));
  45         if (dev) {
  46                 err("Device %s already exists at %x:%x, cannot hot-add\n",
  47                                 pci_name(dev), p_slot->bus, p_slot->device);
  48                 return -EINVAL;
  49         }
  50
  51         num = pci_scan_slot(parent, PCI_DEVFN(p_slot->device, 0));
  52         if (num == 0) {
  53                 err("No new device found\n");
  54                 return -ENODEV;
  55         }
  56
  57         for (fn = 0; fn < 8; fn++) {
  58                 if (!(dev = pci_find_slot(p_slot->bus,
  59                                         PCI_DEVFN(p_slot->device, fn))))
  60                         continue;
  61                 if ((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
  62                         err("Cannot hot-add display device %s\n",
  63                                         pci_name(dev));
  64                         continue;
  65                 }
  66                 if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
  67                                 (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)) {
  68                         /* Find an unused bus number for the new bridge */
  69                         struct pci_bus *child;
  70                         unsigned char busnr, start = parent->secondary;
  71                         unsigned char end = parent->subordinate;
  72                         for (busnr = start; busnr <= end; busnr++) {
  73                                 if (!pci_find_bus(pci_domain_nr(parent),
  74                                                         busnr))
  75                                         break;
  76                         }
  77                         if (busnr >= end) {
  78                                 err("No free bus for hot-added bridge\n");
  79                                 continue;
  80                         }
  81                         child = pci_add_new_bus(parent, dev, busnr);
  82                         if (!child) {
  83                                 err("Cannot add new bus for %s\n",
  84                                                 pci_name(dev));
  85                                 continue;
  86                         }
  87                         child->subordinate = pci_do_scan_bus(child);
  88                         pci_bus_size_bridges(child);
  89                 }
  90                 /* TBD: program firmware provided _HPP values */
  91                 /* program_fw_provided_values(dev); */
  92         }
  93
  94         pci_bus_assign_resources(parent);
  95         pci_bus_add_devices(parent);
  96         pci_enable_bridges(parent);
  97         return 0;
  98 }
  99
 100 int pciehp_unconfigure_device(struct slot *p_slot)
 101 {
 102         int rc = 0;
 103         int j;
 104         u8 bctl = 0;
 105
 106         dbg("%s: bus/dev = %x/%x\n", __FUNCTION__, p_slot->bus,
 107                                 p_slot->device);
 108
 109         for (j=0; j<8 ; j++) {
 110                 struct pci_dev* temp = pci_find_slot(p_slot->bus,
 111                                 (p_slot->device << 3) | j);
 112                 if (!temp)
 113                         continue;
 114                 if ((temp->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
 115                         err("Cannot remove display device %s\n",
 116                                         pci_name(temp));
 117                         continue;
 118                 }
 119                 if (temp->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
 120                         pci_read_config_byte(temp, PCI_BRIDGE_CONTROL, &bctl);
 121                         if (bctl & PCI_BRIDGE_CTL_VGA) {
 122                                 err("Cannot remove display device %s\n",
 123                                                 pci_name(temp));
 124                                 continue;
 125                         }
 126                 }
 127                 pci_remove_bus_device(temp);
 128         }
 129         /*
 130          * Some PCI Express root ports require fixup after hot-plug operation.
 131          */
 132         if (pcie_mch_quirk)
 133                 pci_fixup_device(pci_fixup_final, p_slot->ctrl->pci_dev);
 134
 135         return rc;
 136 }
 137