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 COMPONENT "zPCI hpc"
  11 #define pr_fmt(fmt) 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 <linux/init.h>
  19 #include <asm/pci_debug.h>
  20 #include <asm/sclp.h>
  21
  22 #define SLOT_NAME_SIZE  10
  23 static LIST_HEAD(s390_hotplug_slot_list);
  24
  25 MODULE_AUTHOR("Jan Glauber <jang@linux.vnet.ibm.com");
  26 MODULE_DESCRIPTION("Hot Plug PCI Controller for System z");
  27 MODULE_LICENSE("GPL");
  28
  29 static int zpci_fn_configured(enum zpci_state state)
  30 {
  31         return state == ZPCI_FN_STATE_CONFIGURED ||
  32                state == ZPCI_FN_STATE_ONLINE;
  33 }
  34
  35 /*
  36  * struct slot - slot information for each *physical* slot
  37  */
  38 struct slot {
  39         struct list_head slot_list;
  40         struct hotplug_slot *hotplug_slot;
  41         struct zpci_dev *zdev;
  42 };
  43
  44 static inline int slot_configure(struct slot *slot)
  45 {
  46         int ret = sclp_pci_configure(slot->zdev->fid);
  47
  48         zpci_dbg(3, "conf fid:%x, rc:%d\n", slot->zdev->fid, ret);
  49         if (!ret)
  50                 slot->zdev->state = ZPCI_FN_STATE_CONFIGURED;
  51
  52         return ret;
  53 }
  54
  55 static inline int slot_deconfigure(struct slot *slot)
  56 {
  57         int ret = sclp_pci_deconfigure(slot->zdev->fid);
  58
  59         zpci_dbg(3, "deconf fid:%x, rc:%d\n", slot->zdev->fid, ret);
  60         if (!ret)
  61                 slot->zdev->state = ZPCI_FN_STATE_STANDBY;
  62
  63         return ret;
  64 }
  65
  66 static int enable_slot(struct hotplug_slot *hotplug_slot)
  67 {
  68         struct slot *slot = hotplug_slot->private;
  69         int rc;
  70
  71         if (slot->zdev->state != ZPCI_FN_STATE_STANDBY)
  72                 return -EIO;
  73
  74         rc = slot_configure(slot);
  75         if (rc)
  76                 return rc;
  77
  78         rc = zpci_enable_device(slot->zdev);
  79         if (rc)
  80                 goto out_deconfigure;
  81
  82         pci_scan_slot(slot->zdev->bus, ZPCI_DEVFN);
  83         pci_bus_add_devices(slot->zdev->bus);
  84
  85         return rc;
  86
  87 out_deconfigure:
  88         slot_deconfigure(slot);
  89         return rc;
  90 }
  91
  92 static int disable_slot(struct hotplug_slot *hotplug_slot)
  93 {
  94         struct slot *slot = hotplug_slot->private;
  95         int rc;
  96
  97         if (!zpci_fn_configured(slot->zdev->state))
  98                 return -EIO;
  99
 100         if (slot->zdev->pdev)
 101                 pci_stop_and_remove_bus_device(slot->zdev->pdev);
 102
 103         rc = zpci_disable_device(slot->zdev);
 104         if (rc)
 105                 return rc;
 106
 107         return slot_deconfigure(slot);
 108 }
 109
 110 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
 111 {
 112         struct slot *slot = hotplug_slot->private;
 113
 114         switch (slot->zdev->state) {
 115         case ZPCI_FN_STATE_STANDBY:
 116                 *value = 0;
 117                 break;
 118         default:
 119                 *value = 1;
 120                 break;
 121         }
 122         return 0;
 123 }
 124
 125 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
 126 {
 127         /* if the slot exits it always contains a function */
 128         *value = 1;
 129         return 0;
 130 }
 131
 132 static void release_slot(struct hotplug_slot *hotplug_slot)
 133 {
 134         struct slot *slot = hotplug_slot->private;
 135
 136         pr_debug("%s - physical_slot = %s\n", __func__, hotplug_slot_name(hotplug_slot));
 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                 pr_err("pci_hp_register failed with error %d\n", rc);
 188                 goto error_reg;
 189         }
 190         list_add(&slot->slot_list, &s390_hotplug_slot_list);
 191         return 0;
 192
 193 error_reg:
 194         kfree(info);
 195 error_info:
 196         kfree(hotplug_slot);
 197 error_hp:
 198         kfree(slot);
 199 error:
 200         return -ENOMEM;
 201 }
 202
 203 void zpci_exit_slot(struct zpci_dev *zdev)
 204 {
 205         struct list_head *tmp, *n;
 206         struct slot *slot;
 207
 208         list_for_each_safe(tmp, n, &s390_hotplug_slot_list) {
 209                 slot = list_entry(tmp, struct slot, slot_list);
 210                 if (slot->zdev != zdev)
 211                         continue;
 212                 list_del(&slot->slot_list);
 213                 pci_hp_deregister(slot->hotplug_slot);
 214         }
 215 }