1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * PCI Hot Plug Controller Driver for System z
4 *
5 * Copyright 2012 IBM Corp.
6 *
7 * Author(s):
8 * Jan Glauber <jang@linux.vnet.ibm.com>
9 */
10
11 #define KMSG_COMPONENT "zpci"
12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
13
14 #include <linux/kernel.h>
15 #include <linux/slab.h>
16 #include <linux/pci.h>
17 #include <linux/pci_hotplug.h>
18 #include <asm/pci_debug.h>
19 #include <asm/sclp.h>
20
21 #define SLOT_NAME_SIZE 10
22
zpci_fn_configured(enum zpci_state state)23 static int zpci_fn_configured(enum zpci_state state)
24 {
25 return state == ZPCI_FN_STATE_CONFIGURED ||
26 state == ZPCI_FN_STATE_ONLINE;
27 }
28
zdev_configure(struct zpci_dev * zdev)29 static inline int zdev_configure(struct zpci_dev *zdev)
30 {
31 int ret = sclp_pci_configure(zdev->fid);
32
33 zpci_dbg(3, "conf fid:%x, rc:%d\n", zdev->fid, ret);
34 if (!ret)
35 zdev->state = ZPCI_FN_STATE_CONFIGURED;
36
37 return ret;
38 }
39
zdev_deconfigure(struct zpci_dev * zdev)40 static inline int zdev_deconfigure(struct zpci_dev *zdev)
41 {
42 int ret = sclp_pci_deconfigure(zdev->fid);
43
44 zpci_dbg(3, "deconf fid:%x, rc:%d\n", zdev->fid, ret);
45 if (!ret)
46 zdev->state = ZPCI_FN_STATE_STANDBY;
47
48 return ret;
49 }
50
enable_slot(struct hotplug_slot * hotplug_slot)51 static int enable_slot(struct hotplug_slot *hotplug_slot)
52 {
53 struct zpci_dev *zdev = container_of(hotplug_slot, struct zpci_dev,
54 hotplug_slot);
55 struct zpci_bus *zbus = zdev->zbus;
56 int rc;
57
58 if (zdev->state != ZPCI_FN_STATE_STANDBY)
59 return -EIO;
60
61 rc = zdev_configure(zdev);
62 if (rc)
63 return rc;
64
65 rc = zpci_enable_device(zdev);
66 if (rc)
67 goto out_deconfigure;
68
69 pci_scan_slot(zbus->bus, zdev->devfn);
70 pci_lock_rescan_remove();
71 pci_bus_add_devices(zbus->bus);
72 pci_unlock_rescan_remove();
73
74 return rc;
75
76 out_deconfigure:
77 zdev_deconfigure(zdev);
78 return rc;
79 }
80
disable_slot(struct hotplug_slot * hotplug_slot)81 static int disable_slot(struct hotplug_slot *hotplug_slot)
82 {
83 struct zpci_dev *zdev = container_of(hotplug_slot, struct zpci_dev,
84 hotplug_slot);
85 struct pci_dev *pdev;
86 int rc;
87
88 if (!zpci_fn_configured(zdev->state))
89 return -EIO;
90
91 pdev = pci_get_slot(zdev->zbus->bus, zdev->devfn);
92 if (pdev && pci_num_vf(pdev)) {
93 pci_dev_put(pdev);
94 return -EBUSY;
95 }
96
97 zpci_remove_device(zdev);
98
99 rc = zpci_disable_device(zdev);
100 if (rc)
101 return rc;
102
103 return zdev_deconfigure(zdev);
104 }
105
get_power_status(struct hotplug_slot * hotplug_slot,u8 * value)106 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
107 {
108 struct zpci_dev *zdev = container_of(hotplug_slot, struct zpci_dev,
109 hotplug_slot);
110
111 switch (zdev->state) {
112 case ZPCI_FN_STATE_STANDBY:
113 *value = 0;
114 break;
115 default:
116 *value = 1;
117 break;
118 }
119 return 0;
120 }
121
get_adapter_status(struct hotplug_slot * hotplug_slot,u8 * value)122 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
123 {
124 /* if the slot exits it always contains a function */
125 *value = 1;
126 return 0;
127 }
128
129 static const struct hotplug_slot_ops s390_hotplug_slot_ops = {
130 .enable_slot = enable_slot,
131 .disable_slot = disable_slot,
132 .get_power_status = get_power_status,
133 .get_adapter_status = get_adapter_status,
134 };
135
zpci_init_slot(struct zpci_dev * zdev)136 int zpci_init_slot(struct zpci_dev *zdev)
137 {
138 char name[SLOT_NAME_SIZE];
139 struct zpci_bus *zbus = zdev->zbus;
140
141 zdev->hotplug_slot.ops = &s390_hotplug_slot_ops;
142
143 snprintf(name, SLOT_NAME_SIZE, "%08x", zdev->fid);
144 return pci_hp_register(&zdev->hotplug_slot, zbus->bus,
145 zdev->devfn, name);
146 }
147
zpci_exit_slot(struct zpci_dev * zdev)148 void zpci_exit_slot(struct zpci_dev *zdev)
149 {
150 pci_hp_deregister(&zdev->hotplug_slot);
151 }
152
