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 	kfree(slot->hotplug_slot->info);
25 	kfree(slot->name);
26 	kfree(slot->hotplug_slot);
27 	kfree(slot);
28 }
29 
30 struct slot *alloc_slot_struct(struct device_node *dn,
31 		int drc_index, char *drc_name, int power_domain)
32 {
33 	struct slot *slot;
34 
35 	slot = kzalloc(sizeof(struct slot), GFP_KERNEL);
36 	if (!slot)
37 		goto error_nomem;
38 	slot->hotplug_slot = kzalloc(sizeof(struct hotplug_slot), GFP_KERNEL);
39 	if (!slot->hotplug_slot)
40 		goto error_slot;
41 	slot->hotplug_slot->info = kzalloc(sizeof(struct hotplug_slot_info),
42 					   GFP_KERNEL);
43 	if (!slot->hotplug_slot->info)
44 		goto error_hpslot;
45 	slot->name = kstrdup(drc_name, GFP_KERNEL);
46 	if (!slot->name)
47 		goto error_info;
48 	slot->dn = dn;
49 	slot->index = drc_index;
50 	slot->power_domain = power_domain;
51 	slot->hotplug_slot->private = slot;
52 	slot->hotplug_slot->ops = &rpaphp_hotplug_slot_ops;
53 
54 	return (slot);
55 
56 error_info:
57 	kfree(slot->hotplug_slot->info);
58 error_hpslot:
59 	kfree(slot->hotplug_slot);
60 error_slot:
61 	kfree(slot);
62 error_nomem:
63 	return NULL;
64 }
65 
66 static int is_registered(struct slot *slot)
67 {
68 	struct slot *tmp_slot;
69 
70 	list_for_each_entry(tmp_slot, &rpaphp_slot_head, rpaphp_slot_list) {
71 		if (!strcmp(tmp_slot->name, slot->name))
72 			return 1;
73 	}
74 	return 0;
75 }
76 
77 int rpaphp_deregister_slot(struct slot *slot)
78 {
79 	int retval = 0;
80 	struct hotplug_slot *php_slot = slot->hotplug_slot;
81 
82 	 dbg("%s - Entry: deregistering slot=%s\n",
83 		__func__, slot->name);
84 
85 	list_del(&slot->rpaphp_slot_list);
86 	pci_hp_deregister(php_slot);
87 	dealloc_slot_struct(slot);
88 
89 	dbg("%s - Exit: rc[%d]\n", __func__, retval);
90 	return retval;
91 }
92 EXPORT_SYMBOL_GPL(rpaphp_deregister_slot);
93 
94 int rpaphp_register_slot(struct slot *slot)
95 {
96 	struct hotplug_slot *php_slot = slot->hotplug_slot;
97 	struct device_node *child;
98 	u32 my_index;
99 	int retval;
100 	int slotno = -1;
101 
102 	dbg("%s registering slot:path[%pOF] index[%x], name[%s] pdomain[%x] type[%d]\n",
103 		__func__, slot->dn, slot->index, slot->name,
104 		slot->power_domain, slot->type);
105 
106 	/* should not try to register the same slot twice */
107 	if (is_registered(slot)) {
108 		err("rpaphp_register_slot: slot[%s] is already registered\n", slot->name);
109 		return -EAGAIN;
110 	}
111 
112 	for_each_child_of_node(slot->dn, child) {
113 		retval = of_property_read_u32(child, "ibm,my-drc-index", &my_index);
114 		if (my_index == slot->index) {
115 			slotno = PCI_SLOT(PCI_DN(child)->devfn);
116 			of_node_put(child);
117 			break;
118 		}
119 	}
120 
121 	retval = pci_hp_register(php_slot, slot->bus, slotno, slot->name);
122 	if (retval) {
123 		err("pci_hp_register failed with error %d\n", retval);
124 		return retval;
125 	}
126 
127 	/* add slot to our internal list */
128 	list_add(&slot->rpaphp_slot_list, &rpaphp_slot_head);
129 	info("Slot [%s] registered\n", slot->name);
130 	return 0;
131 }
132