arch/powerpc/kernel/eeh_dev.c

   1 /*
   2  * The file intends to implement dynamic creation of EEH device, which will
   3  * be bound with OF node and PCI device simutaneously. The EEH devices would
   4  * be foundamental information for EEH core components to work proerly. Besides,
   5  * We have to support multiple situations where dynamic creation of EEH device
   6  * is required:
   7  *
   8  * 1) Before PCI emunation starts, we need create EEH devices according to the
   9  *    PCI sensitive OF nodes.
  10  * 2) When PCI emunation is done, we need do the binding between PCI device and
  11  *    the associated EEH device.
  12  * 3) DR (Dynamic Reconfiguration) would create PCI sensitive OF node. EEH device
  13  *    will be created while PCI sensitive OF node is detected from DR.
  14  * 4) PCI hotplug needs redoing the binding between PCI device and EEH device. If
  15  *    PHB is newly inserted, we also need create EEH devices accordingly.
  16  *
  17  * Copyright Benjamin Herrenschmidt & Gavin Shan, IBM Corporation 2012.
  18  *
  19  * This program is free software; you can redistribute it and/or modify
  20  * it under the terms of the GNU General Public License as published by
  21  * the Free Software Foundation; either version 2 of the License, or
  22  * (at your option) any later version.
  23  *
  24  * This program is distributed in the hope that it will be useful,
  25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27  * GNU General Public License for more details.
  28  *
  29  * You should have received a copy of the GNU General Public License
  30  * along with this program; if not, write to the Free Software
  31  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  32  */
  33
  34 #include <linux/export.h>
  35 #include <linux/gfp.h>
  36 #include <linux/init.h>
  37 #include <linux/kernel.h>
  38 #include <linux/pci.h>
  39 #include <linux/string.h>
  40
  41 #include <asm/pci-bridge.h>
  42 #include <asm/ppc-pci.h>
  43
  44 /**
  45  * eeh_dev_init - Create EEH device according to OF node
  46  * @dn: device node
  47  * @data: PHB
  48  *
  49  * It will create EEH device according to the given OF node. The function
  50  * might be called by PCI emunation, DR, PHB hotplug.
  51  */
  52 void *eeh_dev_init(struct device_node *dn, void *data)
  53 {
  54         struct pci_controller *phb = data;
  55         struct eeh_dev *edev;
  56
  57         /* Allocate EEH device */
  58         edev = kzalloc(sizeof(*edev), GFP_KERNEL);
  59         if (!edev) {
  60                 pr_warning("%s: out of memory\n", __func__);
  61                 return NULL;
  62         }
  63
  64         /* Associate EEH device with OF node */
  65         PCI_DN(dn)->edev = edev;
  66         edev->dn  = dn;
  67         edev->phb = phb;
  68         INIT_LIST_HEAD(&edev->list);
  69
  70         return NULL;
  71 }
  72
  73 /**
  74  * eeh_dev_phb_init_dynamic - Create EEH devices for devices included in PHB
  75  * @phb: PHB
  76  *
  77  * Scan the PHB OF node and its child association, then create the
  78  * EEH devices accordingly
  79  */
  80 void eeh_dev_phb_init_dynamic(struct pci_controller *phb)
  81 {
  82         struct device_node *dn = phb->dn;
  83
  84         /* EEH PE for PHB */
  85         eeh_phb_pe_create(phb);
  86
  87         /* EEH device for PHB */
  88         eeh_dev_init(dn, phb);
  89
  90         /* EEH devices for children OF nodes */
  91         traverse_pci_devices(dn, eeh_dev_init, phb);
  92 }
  93
  94 /**
  95  * eeh_dev_phb_init - Create EEH devices for devices included in existing PHBs
  96  *
  97  * Scan all the existing PHBs and create EEH devices for their OF
  98  * nodes and their children OF nodes
  99  */
 100 static int __init eeh_dev_phb_init(void)
 101 {
 102         struct pci_controller *phb, *tmp;
 103
 104         list_for_each_entry_safe(phb, tmp, &hose_list, list_node)
 105                 eeh_dev_phb_init_dynamic(phb);
 106
 107         pr_info("EEH: devices created\n");
 108
 109         return 0;
 110 }
 111
 112 core_initcall(eeh_dev_phb_init);