arch/powerpc/platforms/pseries/pci_dlpar.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * PCI Dynamic LPAR, PCI Hot Plug and PCI EEH recovery code
   4  * for RPA-compliant PPC64 platform.
   5  * Copyright (C) 2003 Linda Xie <lxie@us.ibm.com>
   6  * Copyright (C) 2005 International Business Machines
   7  *
   8  * Updates, 2005, John Rose <johnrose@austin.ibm.com>
   9  * Updates, 2005, Linas Vepstas <linas@austin.ibm.com>
  10  */
  11
  12 #include <linux/pci.h>
  13 #include <linux/export.h>
  14 #include <asm/pci-bridge.h>
  15 #include <asm/ppc-pci.h>
  16 #include <asm/firmware.h>
  17 #include <asm/eeh.h>
  18
  19 #include "pseries.h"
  20
  21 struct pci_controller *init_phb_dynamic(struct device_node *dn)
  22 {
  23         struct pci_controller *phb;
  24
  25         pr_debug("PCI: Initializing new hotplug PHB %pOF\n", dn);
  26
  27         phb = pcibios_alloc_controller(dn);
  28         if (!phb)
  29                 return NULL;
  30         rtas_setup_phb(phb);
  31         pci_process_bridge_OF_ranges(phb, dn, 0);
  32         phb->controller_ops = pseries_pci_controller_ops;
  33
  34         pci_devs_phb_init_dynamic(phb);
  35
  36         pseries_msi_allocate_domains(phb);
  37
  38         ppc_iommu_register_device(phb);
  39
  40         /* Create EEH devices for the PHB */
  41         eeh_phb_pe_create(phb);
  42
  43         if (dn->child)
  44                 pseries_eeh_init_edev_recursive(PCI_DN(dn));
  45
  46         pcibios_scan_phb(phb);
  47         pcibios_finish_adding_to_bus(phb->bus);
  48
  49         return phb;
  50 }
  51 EXPORT_SYMBOL_GPL(init_phb_dynamic);
  52
  53 /* RPA-specific bits for removing PHBs */
  54 int remove_phb_dynamic(struct pci_controller *phb)
  55 {
  56         struct pci_bus *b = phb->bus;
  57         struct pci_host_bridge *host_bridge = to_pci_host_bridge(b->bridge);
  58         struct resource *res;
  59         int rc, i;
  60
  61         pr_debug("PCI: Removing PHB %04x:%02x...\n",
  62                  pci_domain_nr(b), b->number);
  63
  64         /* We cannot to remove a root bus that has children */
  65         if (!(list_empty(&b->children) && list_empty(&b->devices)))
  66                 return -EBUSY;
  67
  68         /* We -know- there aren't any child devices anymore at this stage
  69          * and thus, we can safely unmap the IO space as it's not in use
  70          */
  71         res = &phb->io_resource;
  72         if (res->flags & IORESOURCE_IO) {
  73                 rc = pcibios_unmap_io_space(b);
  74                 if (rc) {
  75                         printk(KERN_ERR "%s: failed to unmap IO on bus %s\n",
  76                                __func__, b->name);
  77                         return 1;
  78                 }
  79         }
  80
  81         ppc_iommu_unregister_device(phb);
  82
  83         pseries_msi_free_domains(phb);
  84
  85         /* Keep a reference so phb isn't freed yet */
  86         get_device(&host_bridge->dev);
  87
  88         /* Remove the PCI bus and unregister the bridge device from sysfs */
  89         phb->bus = NULL;
  90         pci_remove_bus(b);
  91         host_bridge->bus = NULL;
  92         device_unregister(&host_bridge->dev);
  93
  94         /* Now release the IO resource */
  95         if (res->flags & IORESOURCE_IO)
  96                 release_resource(res);
  97
  98         /* Release memory resources */
  99         for (i = 0; i < 3; ++i) {
 100                 res = &phb->mem_resources[i];
 101                 if (!(res->flags & IORESOURCE_MEM))
 102                         continue;
 103                 release_resource(res);
 104         }
 105
 106         /*
 107          * The pci_controller data structure is freed by
 108          * the pcibios_free_controller_deferred() callback;
 109          * see pseries_root_bridge_prepare().
 110          */
 111         put_device(&host_bridge->dev);
 112
 113         return 0;
 114 }
 115 EXPORT_SYMBOL_GPL(remove_phb_dynamic);