drivers/pci/hotplug/s390_pci_hpc.c

   1 /*
   2  * PCI Hot Plug Controller Driver for System z
   3  *
   4  * Copyright 2012 IBM Corp.
   5  *
   6  * Author(s):
   7  *   Jan Glauber <jang@linux.vnet.ibm.com>
   8  */
   9
  10 #define KMSG_COMPONENT "zpci"
  11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  12
  13 #include <linux/module.h>
  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 static LIST_HEAD(s390_hotplug_slot_list);
  23
  24 MODULE_AUTHOR("Jan Glauber <jang@linux.vnet.ibm.com");
  25 MODULE_DESCRIPTION("Hot Plug PCI Controller for System z");
  26 MODULE_LICENSE("GPL");
  27
  28 static int zpci_fn_configured(enum zpci_state state)
  29 {
  30         return state == ZPCI_FN_STATE_CONFIGURED ||
  31                state == ZPCI_FN_STATE_ONLINE;
  32 }
  33
  34 /*
  35  * struct slot - slot information for each *physical* slot
  36  */
  37 struct slot {
  38         struct list_head slot_list;
  39         struct hotplug_slot *hotplug_slot;
  40         struct zpci_dev *zdev;
  41 };
  42
  43 static inline int slot_configure(struct slot *slot)
  44 {
  45         int ret = sclp_pci_configure(slot->zdev->fid);
  46
  47         zpci_dbg(3, "conf fid:%x, rc:%d\n", slot->zdev->fid, ret);
  48         if (!ret)
  49                 slot->zdev->state = ZPCI_FN_STATE_CONFIGURED;
  50
  51         return ret;
  52 }
  53
  54 static inline int slot_deconfigure(struct slot *slot)
  55 {
  56         int ret = sclp_pci_deconfigure(slot->zdev->fid);
  57
  58         zpci_dbg(3, "deconf fid:%x, rc:%d\n", slot->zdev->fid, ret);
  59         if (!ret)
  60                 slot->zdev->state = ZPCI_FN_STATE_STANDBY;
  61
  62         return ret;
  63 }
  64
  65 static int enable_slot(struct hotplug_slot *hotplug_slot)
  66 {
  67         struct slot *slot = hotplug_slot->private;
  68         int rc;
  69
  70         if (slot->zdev->state != ZPCI_FN_STATE_STANDBY)
  71                 return -EIO;
  72
  73         rc = slot_configure(slot);
  74         if (rc)
  75                 return rc;
  76
  77         rc = zpci_enable_device(slot->zdev);
  78         if (rc)
  79                 goto out_deconfigure;
  80
  81         pci_scan_slot(slot->zdev->bus, ZPCI_DEVFN);
  82         pci_lock_rescan_remove();
  83         pci_bus_add_devices(slot->zdev->bus);
  84         pci_unlock_rescan_remove();
  85
  86         return rc;
  87
  88 out_deconfigure:
  89         slot_deconfigure(slot);
  90         return rc;
  91 }
  92
  93 static int disable_slot(struct hotplug_slot *hotplug_slot)
  94 {
  95         struct slot *slot = hotplug_slot->private;
  96         int rc;
  97
  98         if (!zpci_fn_configured(slot->zdev->state))
  99                 return -EIO;
 100
 101         if (slot->zdev->pdev)
 102                 pci_stop_and_remove_bus_device_locked(slot->zdev->pdev);
 103
 104         rc = zpci_disable_device(slot->zdev);
 105         if (rc)
 106                 return rc;
 107
 108         return slot_deconfigure(slot);
 109 }
 110
 111 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
 112 {
 113         struct slot *slot = hotplug_slot->private;
 114
 115         switch (slot->zdev->state) {
 116         case ZPCI_FN_STATE_STANDBY:
 117                 *value = 0;
 118                 break;
 119         default:
 120                 *value = 1;
 121                 break;
 122         }
 123         return 0;
 124 }
 125
 126 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
 127 {
 128         /* if the slot exits it always contains a function */
 129         *value = 1;
 130         return 0;
 131 }
 132
 133 static void release_slot(struct hotplug_slot *hotplug_slot)
 134 {
 135         struct slot *slot = hotplug_slot->private;
 136
 137         kfree(slot->hotplug_slot->info);
 138         kfree(slot->hotplug_slot);
 139         kfree(slot);
 140 }
 141
 142 static struct hotplug_slot_ops s390_hotplug_slot_ops = {
 143         .enable_slot =          enable_slot,
 144         .disable_slot =         disable_slot,
 145         .get_power_status =     get_power_status,
 146         .get_adapter_status =   get_adapter_status,
 147 };
 148
 149 int zpci_init_slot(struct zpci_dev *zdev)
 150 {
 151         struct hotplug_slot *hotplug_slot;
 152         struct hotplug_slot_info *info;
 153         char name[SLOT_NAME_SIZE];
 154         struct slot *slot;
 155         int rc;
 156
 157         if (!zdev)
 158                 return 0;
 159
 160         slot = kzalloc(sizeof(*slot), GFP_KERNEL);
 161         if (!slot)
 162                 goto error;
 163
 164         hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL);
 165         if (!hotplug_slot)
 166                 goto error_hp;
 167         hotplug_slot->private = slot;
 168
 169         slot->hotplug_slot = hotplug_slot;
 170         slot->zdev = zdev;
 171
 172         info = kzalloc(sizeof(*info), GFP_KERNEL);
 173         if (!info)
 174                 goto error_info;
 175         hotplug_slot->info = info;
 176
 177         hotplug_slot->ops = &s390_hotplug_slot_ops;
 178         hotplug_slot->release = &release_slot;
 179
 180         get_power_status(hotplug_slot, &info->power_status);
 181         get_adapter_status(hotplug_slot, &info->adapter_status);
 182
 183         snprintf(name, SLOT_NAME_SIZE, "%08x", zdev->fid);
 184         rc = pci_hp_register(slot->hotplug_slot, zdev->bus,
 185                              ZPCI_DEVFN, name);
 186         if (rc)
 187                 goto error_reg;
 188
 189         list_add(&slot->slot_list, &s390_hotplug_slot_list);
 190         return 0;
 191
 192 error_reg:
 193         kfree(info);
 194 error_info:
 195         kfree(hotplug_slot);
 196 error_hp:
 197         kfree(slot);
 198 error:
 199         return -ENOMEM;
 200 }
 201
 202 void zpci_exit_slot(struct zpci_dev *zdev)
 203 {
 204         struct list_head *tmp, *n;
 205         struct slot *slot;
 206
 207         list_for_each_safe(tmp, n, &s390_hotplug_slot_list) {
 208                 slot = list_entry(tmp, struct slot, slot_list);
 209                 if (slot->zdev != zdev)
 210                         continue;
 211                 list_del(&slot->slot_list);
 212                 pci_hp_deregister(slot->hotplug_slot);
 213         }
 214 }