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
enable_slot(struct hotplug_slot * hotplug_slot)23 static int enable_slot(struct hotplug_slot *hotplug_slot)
24 {
25 struct zpci_dev *zdev = container_of(hotplug_slot, struct zpci_dev,
26 hotplug_slot);
27 int rc;
28
29 if (zdev->state != ZPCI_FN_STATE_STANDBY)
30 return -EIO;
31
32 rc = sclp_pci_configure(zdev->fid);
33 zpci_dbg(3, "conf fid:%x, rc:%d\n", zdev->fid, rc);
34 if (rc)
35 return rc;
36 zdev->state = ZPCI_FN_STATE_CONFIGURED;
37
38 return zpci_scan_configured_device(zdev, zdev->fh);
39 }
40
disable_slot(struct hotplug_slot * hotplug_slot)41 static int disable_slot(struct hotplug_slot *hotplug_slot)
42 {
43 struct zpci_dev *zdev = container_of(hotplug_slot, struct zpci_dev,
44 hotplug_slot);
45 struct pci_dev *pdev;
46
47 if (zdev->state != ZPCI_FN_STATE_CONFIGURED)
48 return -EIO;
49
50 pdev = pci_get_slot(zdev->zbus->bus, zdev->devfn);
51 if (pdev && pci_num_vf(pdev)) {
52 pci_dev_put(pdev);
53 return -EBUSY;
54 }
55 pci_dev_put(pdev);
56
57 return zpci_deconfigure_device(zdev);
58 }
59
reset_slot(struct hotplug_slot * hotplug_slot,bool probe)60 static int reset_slot(struct hotplug_slot *hotplug_slot, bool probe)
61 {
62 struct zpci_dev *zdev = container_of(hotplug_slot, struct zpci_dev,
63 hotplug_slot);
64
65 if (zdev->state != ZPCI_FN_STATE_CONFIGURED)
66 return -EIO;
67 /*
68 * We can't take the zdev->lock as reset_slot may be called during
69 * probing and/or device removal which already happens under the
70 * zdev->lock. Instead the user should use the higher level
71 * pci_reset_function() or pci_bus_reset() which hold the PCI device
72 * lock preventing concurrent removal. If not using these functions
73 * holding the PCI device lock is required.
74 */
75
76 /* As long as the function is configured we can reset */
77 if (probe)
78 return 0;
79
80 return zpci_hot_reset_device(zdev);
81 }
82
get_power_status(struct hotplug_slot * hotplug_slot,u8 * value)83 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
84 {
85 struct zpci_dev *zdev = container_of(hotplug_slot, struct zpci_dev,
86 hotplug_slot);
87
88 *value = zpci_is_device_configured(zdev) ? 1 : 0;
89 return 0;
90 }
91
get_adapter_status(struct hotplug_slot * hotplug_slot,u8 * value)92 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
93 {
94 /* if the slot exits it always contains a function */
95 *value = 1;
96 return 0;
97 }
98
99 static const struct hotplug_slot_ops s390_hotplug_slot_ops = {
100 .enable_slot = enable_slot,
101 .disable_slot = disable_slot,
102 .reset_slot = reset_slot,
103 .get_power_status = get_power_status,
104 .get_adapter_status = get_adapter_status,
105 };
106
zpci_init_slot(struct zpci_dev * zdev)107 int zpci_init_slot(struct zpci_dev *zdev)
108 {
109 char name[SLOT_NAME_SIZE];
110 struct zpci_bus *zbus = zdev->zbus;
111
112 zdev->hotplug_slot.ops = &s390_hotplug_slot_ops;
113
114 snprintf(name, SLOT_NAME_SIZE, "%08x", zdev->fid);
115 return pci_hp_register(&zdev->hotplug_slot, zbus->bus,
116 zdev->devfn, name);
117 }
118
zpci_exit_slot(struct zpci_dev * zdev)119 void zpci_exit_slot(struct zpci_dev *zdev)
120 {
121 pci_hp_deregister(&zdev->hotplug_slot);
122 }
123