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 	/* Create EEH devices for the PHB */
39 	eeh_phb_pe_create(phb);
40 
41 	if (dn->child)
42 		pseries_eeh_init_edev_recursive(PCI_DN(dn));
43 
44 	pcibios_scan_phb(phb);
45 	pcibios_finish_adding_to_bus(phb->bus);
46 
47 	return phb;
48 }
49 EXPORT_SYMBOL_GPL(init_phb_dynamic);
50 
51 /* RPA-specific bits for removing PHBs */
52 int remove_phb_dynamic(struct pci_controller *phb)
53 {
54 	struct pci_bus *b = phb->bus;
55 	struct pci_host_bridge *host_bridge = to_pci_host_bridge(b->bridge);
56 	struct resource *res;
57 	int rc, i;
58 
59 	pr_debug("PCI: Removing PHB %04x:%02x...\n",
60 		 pci_domain_nr(b), b->number);
61 
62 	/* We cannot to remove a root bus that has children */
63 	if (!(list_empty(&b->children) && list_empty(&b->devices)))
64 		return -EBUSY;
65 
66 	/* We -know- there aren't any child devices anymore at this stage
67 	 * and thus, we can safely unmap the IO space as it's not in use
68 	 */
69 	res = &phb->io_resource;
70 	if (res->flags & IORESOURCE_IO) {
71 		rc = pcibios_unmap_io_space(b);
72 		if (rc) {
73 			printk(KERN_ERR "%s: failed to unmap IO on bus %s\n",
74 			       __func__, b->name);
75 			return 1;
76 		}
77 	}
78 
79 	pseries_msi_free_domains(phb);
80 
81 	/* Remove the PCI bus and unregister the bridge device from sysfs */
82 	phb->bus = NULL;
83 	pci_remove_bus(b);
84 	host_bridge->bus = NULL;
85 	device_unregister(&host_bridge->dev);
86 
87 	/* Now release the IO resource */
88 	if (res->flags & IORESOURCE_IO)
89 		release_resource(res);
90 
91 	/* Release memory resources */
92 	for (i = 0; i < 3; ++i) {
93 		res = &phb->mem_resources[i];
94 		if (!(res->flags & IORESOURCE_MEM))
95 			continue;
96 		release_resource(res);
97 	}
98 
99 	/*
100 	 * The pci_controller data structure is freed by
101 	 * the pcibios_free_controller_deferred() callback;
102 	 * see pseries_root_bridge_prepare().
103 	 */
104 
105 	return 0;
106 }
107 EXPORT_SYMBOL_GPL(remove_phb_dynamic);
108