arch/powerpc/kernel/eeh_dev.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * The file intends to implement dynamic creation of EEH device, which will
   4  * be bound with OF node and PCI device simutaneously. The EEH devices would
   5  * be foundamental information for EEH core components to work proerly. Besides,
   6  * We have to support multiple situations where dynamic creation of EEH device
   7  * is required:
   8  *
   9  * 1) Before PCI emunation starts, we need create EEH devices according to the
  10  *    PCI sensitive OF nodes.
  11  * 2) When PCI emunation is done, we need do the binding between PCI device and
  12  *    the associated EEH device.
  13  * 3) DR (Dynamic Reconfiguration) would create PCI sensitive OF node. EEH device
  14  *    will be created while PCI sensitive OF node is detected from DR.
  15  * 4) PCI hotplug needs redoing the binding between PCI device and EEH device. If
  16  *    PHB is newly inserted, we also need create EEH devices accordingly.
  17  *
  18  * Copyright Benjamin Herrenschmidt & Gavin Shan, IBM Corporation 2012.
  19  */
  20
  21 #include <linux/export.h>
  22 #include <linux/gfp.h>
  23 #include <linux/init.h>
  24 #include <linux/kernel.h>
  25 #include <linux/pci.h>
  26 #include <linux/string.h>
  27
  28 #include <asm/pci-bridge.h>
  29 #include <asm/ppc-pci.h>
  30
  31 /**
  32  * eeh_dev_init - Create EEH device according to OF node
  33  * @pdn: PCI device node
  34  *
  35  * It will create EEH device according to the given OF node. The function
  36  * might be called by PCI emunation, DR, PHB hotplug.
  37  */
  38 struct eeh_dev *eeh_dev_init(struct pci_dn *pdn)
  39 {
  40         struct eeh_dev *edev;
  41
  42         /* Allocate EEH device */
  43         edev = kzalloc(sizeof(*edev), GFP_KERNEL);
  44         if (!edev)
  45                 return NULL;
  46
  47         /* Associate EEH device with OF node */
  48         pdn->edev = edev;
  49         edev->pdn = pdn;
  50         edev->bdfn = (pdn->busno << 8) | pdn->devfn;
  51         edev->controller = pdn->phb;
  52
  53         return edev;
  54 }
  55
  56 /**
  57  * eeh_dev_phb_init_dynamic - Create EEH devices for devices included in PHB
  58  * @phb: PHB
  59  *
  60  * Scan the PHB OF node and its child association, then create the
  61  * EEH devices accordingly
  62  */
  63 void eeh_dev_phb_init_dynamic(struct pci_controller *phb)
  64 {
  65         /* EEH PE for PHB */
  66         eeh_phb_pe_create(phb);
  67 }