1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * RPA Virtual I/O device functions
4  * Copyright (C) 2004 Linda Xie <lxie@us.ibm.com>
5  *
6  * All rights reserved.
7  *
8  * Send feedback to <lxie@us.ibm.com>
9  *
10  */
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/sysfs.h>
14 #include <linux/pci.h>
15 #include <linux/string.h>
16 #include <linux/slab.h>
17 
18 #include <asm/rtas.h>
19 #include "rpaphp.h"
20 
21 /* free up the memory used by a slot */
22 void dealloc_slot_struct(struct slot *slot)
23 {
24 	of_node_put(slot->dn);
25 	kfree(slot->name);
26 	kfree(slot);
27 }
28 
29 struct slot *alloc_slot_struct(struct device_node *dn,
30 		int drc_index, char *drc_name, int power_domain)
31 {
32 	struct slot *slot;
33 
34 	slot = kzalloc(sizeof(struct slot), GFP_KERNEL);
35 	if (!slot)
36 		goto error_nomem;
37 	slot->name = kstrdup(drc_name, GFP_KERNEL);
38 	if (!slot->name)
39 		goto error_slot;
40 	slot->dn = of_node_get(dn);
41 	slot->index = drc_index;
42 	slot->power_domain = power_domain;
43 	slot->hotplug_slot.ops = &rpaphp_hotplug_slot_ops;
44 
45 	return (slot);
46 
47 error_slot:
48 	kfree(slot);
49 error_nomem:
50 	return NULL;
51 }
52 
53 static int is_registered(struct slot *slot)
54 {
55 	struct slot *tmp_slot;
56 
57 	list_for_each_entry(tmp_slot, &rpaphp_slot_head, rpaphp_slot_list) {
58 		if (!strcmp(tmp_slot->name, slot->name))
59 			return 1;
60 	}
61 	return 0;
62 }
63 
64 int rpaphp_deregister_slot(struct slot *slot)
65 {
66 	int retval = 0;
67 	struct hotplug_slot *php_slot = &slot->hotplug_slot;
68 
69 	 dbg("%s - Entry: deregistering slot=%s\n",
70 		__func__, slot->name);
71 
72 	list_del(&slot->rpaphp_slot_list);
73 	pci_hp_deregister(php_slot);
74 	dealloc_slot_struct(slot);
75 
76 	dbg("%s - Exit: rc[%d]\n", __func__, retval);
77 	return retval;
78 }
79 EXPORT_SYMBOL_GPL(rpaphp_deregister_slot);
80 
81 int rpaphp_register_slot(struct slot *slot)
82 {
83 	struct hotplug_slot *php_slot = &slot->hotplug_slot;
84 	struct device_node *child;
85 	u32 my_index;
86 	int retval;
87 	int slotno = -1;
88 
89 	dbg("%s registering slot:path[%pOF] index[%x], name[%s] pdomain[%x] type[%d]\n",
90 		__func__, slot->dn, slot->index, slot->name,
91 		slot->power_domain, slot->type);
92 
93 	/* should not try to register the same slot twice */
94 	if (is_registered(slot)) {
95 		err("rpaphp_register_slot: slot[%s] is already registered\n", slot->name);
96 		return -EAGAIN;
97 	}
98 
99 	for_each_child_of_node(slot->dn, child) {
100 		retval = of_property_read_u32(child, "ibm,my-drc-index", &my_index);
101 		if (my_index == slot->index) {
102 			slotno = PCI_SLOT(PCI_DN(child)->devfn);
103 			of_node_put(child);
104 			break;
105 		}
106 	}
107 
108 	retval = pci_hp_register(php_slot, slot->bus, slotno, slot->name);
109 	if (retval) {
110 		err("pci_hp_register failed with error %d\n", retval);
111 		return retval;
112 	}
113 
114 	/* add slot to our internal list */
115 	list_add(&slot->rpaphp_slot_list, &rpaphp_slot_head);
116 	info("Slot [%s] registered\n", slot->name);
117 	return 0;
118 }
119