arch/powerpc/kernel/pci-hotplug.c

   1 /*
   2  * Derived from "arch/powerpc/platforms/pseries/pci_dlpar.c"
   3  *
   4  * Copyright (C) 2003 Linda Xie <lxie@us.ibm.com>
   5  * Copyright (C) 2005 International Business Machines
   6  *
   7  * Updates, 2005, John Rose <johnrose@austin.ibm.com>
   8  * Updates, 2005, Linas Vepstas <linas@austin.ibm.com>
   9  * Updates, 2013, Gavin Shan <shangw@linux.vnet.ibm.com>
  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
  14  * (at your option) any later version.
  15  */
  16
  17 #include <linux/pci.h>
  18 #include <linux/export.h>
  19 #include <asm/pci-bridge.h>
  20 #include <asm/ppc-pci.h>
  21 #include <asm/firmware.h>
  22 #include <asm/eeh.h>
  23
  24 /**
  25  * pcibios_release_device - release PCI device
  26  * @dev: PCI device
  27  *
  28  * The function is called before releasing the indicated PCI device.
  29  */
  30 void pcibios_release_device(struct pci_dev *dev)
  31 {
  32         eeh_remove_device(dev);
  33 }
  34
  35 /**
  36  * pcibios_remove_pci_devices - remove all devices under this bus
  37  * @bus: the indicated PCI bus
  38  *
  39  * Remove all of the PCI devices under this bus both from the
  40  * linux pci device tree, and from the powerpc EEH address cache.
  41  */
  42 void pcibios_remove_pci_devices(struct pci_bus *bus)
  43 {
  44         struct pci_dev *dev, *tmp;
  45         struct pci_bus *child_bus;
  46
  47         /* First go down child busses */
  48         list_for_each_entry(child_bus, &bus->children, node)
  49                 pcibios_remove_pci_devices(child_bus);
  50
  51         pr_debug("PCI: Removing devices on bus %04x:%02x\n",
  52                  pci_domain_nr(bus),  bus->number);
  53         list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list) {
  54                 pr_debug("   Removing %s...\n", pci_name(dev));
  55                 pci_stop_and_remove_bus_device(dev);
  56         }
  57 }
  58
  59 EXPORT_SYMBOL_GPL(pcibios_remove_pci_devices);
  60
  61 /**
  62  * pcibios_add_pci_devices - adds new pci devices to bus
  63  * @bus: the indicated PCI bus
  64  *
  65  * This routine will find and fixup new pci devices under
  66  * the indicated bus. This routine presumes that there
  67  * might already be some devices under this bridge, so
  68  * it carefully tries to add only new devices.  (And that
  69  * is how this routine differs from other, similar pcibios
  70  * routines.)
  71  */
  72 void pcibios_add_pci_devices(struct pci_bus * bus)
  73 {
  74         int slotno, mode, pass, max;
  75         struct pci_dev *dev;
  76         struct device_node *dn = pci_bus_to_OF_node(bus);
  77
  78         eeh_add_device_tree_early(dn);
  79
  80         mode = PCI_PROBE_NORMAL;
  81         if (ppc_md.pci_probe_mode)
  82                 mode = ppc_md.pci_probe_mode(bus);
  83
  84         if (mode == PCI_PROBE_DEVTREE) {
  85                 /* use ofdt-based probe */
  86                 of_rescan_bus(dn, bus);
  87         } else if (mode == PCI_PROBE_NORMAL) {
  88                 /*
  89                  * Use legacy probe. In the partial hotplug case, we
  90                  * probably have grandchildren devices unplugged. So
  91                  * we don't check the return value from pci_scan_slot() in
  92                  * order for fully rescan all the way down to pick them up.
  93                  * They can have been removed during partial hotplug.
  94                  */
  95                 slotno = PCI_SLOT(PCI_DN(dn->child)->devfn);
  96                 pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
  97                 pcibios_setup_bus_devices(bus);
  98                 max = bus->busn_res.start;
  99                 for (pass = 0; pass < 2; pass++) {
 100                         list_for_each_entry(dev, &bus->devices, bus_list) {
 101                                 if (pci_is_bridge(dev))
 102                                         max = pci_scan_bridge(bus, dev,
 103                                                               max, pass);
 104                         }
 105                 }
 106         }
 107         pcibios_finish_adding_to_bus(bus);
 108 }
 109 EXPORT_SYMBOL_GPL(pcibios_add_pci_devices);