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