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);
116