drivers/ieee1394/hosts.c

   1 /*
   2  * IEEE 1394 for Linux
   3  *
   4  * Low level (host adapter) management.
   5  *
   6  * Copyright (C) 1999 Andreas E. Bombe
   7  * Copyright (C) 1999 Emanuel Pirker
   8  *
   9  * This code is licensed under the GPL.  See the file COPYING in the root
  10  * directory of the kernel sources for details.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/types.h>
  15 #include <linux/list.h>
  16 #include <linux/init.h>
  17 #include <linux/slab.h>
  18 #include <linux/pci.h>
  19 #include <linux/timer.h>
  20 #include <linux/jiffies.h>
  21 #include <linux/mutex.h>
  22
  23 #include "csr1212.h"
  24 #include "ieee1394.h"
  25 #include "ieee1394_types.h"
  26 #include "hosts.h"
  27 #include "ieee1394_core.h"
  28 #include "highlevel.h"
  29 #include "nodemgr.h"
  30 #include "csr.h"
  31 #include "config_roms.h"
  32
  33
  34 static void delayed_reset_bus(struct work_struct *work)
  35 {
  36         struct hpsb_host *host =
  37                 container_of(work, struct hpsb_host, delayed_reset.work);
  38         int generation = host->csr.generation + 1;
  39
  40         /* The generation field rolls over to 2 rather than 0 per IEEE
  41          * 1394a-2000. */
  42         if (generation > 0xf || generation < 2)
  43                 generation = 2;
  44
  45         CSR_SET_BUS_INFO_GENERATION(host->csr.rom, generation);
  46         if (csr1212_generate_csr_image(host->csr.rom) != CSR1212_SUCCESS) {
  47                 /* CSR image creation failed, reset generation field and do not
  48                  * issue a bus reset. */
  49                 CSR_SET_BUS_INFO_GENERATION(host->csr.rom, host->csr.generation);
  50                 return;
  51         }
  52
  53         host->csr.generation = generation;
  54
  55         host->update_config_rom = 0;
  56         if (host->driver->set_hw_config_rom)
  57                 host->driver->set_hw_config_rom(host, host->csr.rom->bus_info_data);
  58
  59         host->csr.gen_timestamp[host->csr.generation] = jiffies;
  60         hpsb_reset_bus(host, SHORT_RESET);
  61 }
  62
  63 static int dummy_transmit_packet(struct hpsb_host *h, struct hpsb_packet *p)
  64 {
  65         return 0;
  66 }
  67
  68 static int dummy_devctl(struct hpsb_host *h, enum devctl_cmd c, int arg)
  69 {
  70         return -1;
  71 }
  72
  73 static int dummy_isoctl(struct hpsb_iso *iso, enum isoctl_cmd command, unsigned long arg)
  74 {
  75         return -1;
  76 }
  77
  78 static struct hpsb_host_driver dummy_driver = {
  79         .transmit_packet = dummy_transmit_packet,
  80         .devctl =          dummy_devctl,
  81         .isoctl =          dummy_isoctl
  82 };
  83
  84 static int alloc_hostnum_cb(struct hpsb_host *host, void *__data)
  85 {
  86         int *hostnum = __data;
  87
  88         if (host->id == *hostnum)
  89                 return 1;
  90
  91         return 0;
  92 }
  93
  94 /*
  95  * The pending_packet_queue is special in that it's processed
  96  * from hardirq context too (such as hpsb_bus_reset()). Hence
  97  * split the lock class from the usual networking skb-head
  98  * lock class by using a separate key for it:
  99  */
 100 static struct lock_class_key pending_packet_queue_key;
 101
 102 static DEFINE_MUTEX(host_num_alloc);
 103
 104 /**
 105  * hpsb_alloc_host - allocate a new host controller.
 106  * @drv: the driver that will manage the host controller
 107  * @extra: number of extra bytes to allocate for the driver
 108  *
 109  * Allocate a &hpsb_host and initialize the general subsystem specific
 110  * fields.  If the driver needs to store per host data, as drivers
 111  * usually do, the amount of memory required can be specified by the
 112  * @extra parameter.  Once allocated, the driver should initialize the
 113  * driver specific parts, enable the controller and make it available
 114  * to the general subsystem using hpsb_add_host().
 115  *
 116  * Return Value: a pointer to the &hpsb_host if successful, %NULL if
 117  * no memory was available.
 118  */
 119 struct hpsb_host *hpsb_alloc_host(struct hpsb_host_driver *drv, size_t extra,
 120                                   struct device *dev)
 121 {
 122         struct hpsb_host *h;
 123         int i;
 124         int hostnum = 0;
 125
 126         h = kzalloc(sizeof(*h) + extra, SLAB_KERNEL);
 127         if (!h)
 128                 return NULL;
 129
 130         h->csr.rom = csr1212_create_csr(&csr_bus_ops, CSR_BUS_INFO_SIZE, h);
 131         if (!h->csr.rom) {
 132                 kfree(h);
 133                 return NULL;
 134         }
 135
 136         h->hostdata = h + 1;
 137         h->driver = drv;
 138
 139         skb_queue_head_init(&h->pending_packet_queue);
 140         lockdep_set_class(&h->pending_packet_queue.lock,
 141                            &pending_packet_queue_key);
 142         INIT_LIST_HEAD(&h->addr_space);
 143
 144         for (i = 2; i < 16; i++)
 145                 h->csr.gen_timestamp[i] = jiffies - 60 * HZ;
 146
 147         atomic_set(&h->generation, 0);
 148
 149         INIT_DELAYED_WORK(&h->delayed_reset, delayed_reset_bus);
 150
 151         init_timer(&h->timeout);
 152         h->timeout.data = (unsigned long) h;
 153         h->timeout.function = abort_timedouts;
 154         h->timeout_interval = HZ / 20; // 50ms by default
 155
 156         h->topology_map = h->csr.topology_map + 3;
 157         h->speed_map = (u8 *)(h->csr.speed_map + 2);
 158
 159         mutex_lock(&host_num_alloc);
 160
 161         while (nodemgr_for_each_host(&hostnum, alloc_hostnum_cb))
 162                 hostnum++;
 163
 164         h->id = hostnum;
 165
 166         memcpy(&h->device, &nodemgr_dev_template_host, sizeof(h->device));
 167         h->device.parent = dev;
 168         snprintf(h->device.bus_id, BUS_ID_SIZE, "fw-host%d", h->id);
 169
 170         h->class_dev.dev = &h->device;
 171         h->class_dev.class = &hpsb_host_class;
 172         snprintf(h->class_dev.class_id, BUS_ID_SIZE, "fw-host%d", h->id);
 173
 174         device_register(&h->device);
 175         class_device_register(&h->class_dev);
 176         get_device(&h->device);
 177
 178         mutex_unlock(&host_num_alloc);
 179
 180         return h;
 181 }
 182
 183 int hpsb_add_host(struct hpsb_host *host)
 184 {
 185         if (hpsb_default_host_entry(host))
 186                 return -ENOMEM;
 187
 188         hpsb_add_extra_config_roms(host);
 189
 190         highlevel_add_host(host);
 191
 192         return 0;
 193 }
 194
 195 void hpsb_remove_host(struct hpsb_host *host)
 196 {
 197         host->is_shutdown = 1;
 198
 199         cancel_delayed_work(&host->delayed_reset);
 200         flush_scheduled_work();
 201
 202         host->driver = &dummy_driver;
 203
 204         highlevel_remove_host(host);
 205
 206         hpsb_remove_extra_config_roms(host);
 207
 208         class_device_unregister(&host->class_dev);
 209         device_unregister(&host->device);
 210 }
 211
 212 int hpsb_update_config_rom_image(struct hpsb_host *host)
 213 {
 214         unsigned long reset_delay;
 215         int next_gen = host->csr.generation + 1;
 216
 217         if (!host->update_config_rom)
 218                 return -EINVAL;
 219
 220         if (next_gen > 0xf)
 221                 next_gen = 2;
 222
 223         /* Stop the delayed interrupt, we're about to change the config rom and
 224          * it would be a waste to do a bus reset twice. */
 225         cancel_delayed_work(&host->delayed_reset);
 226
 227         /* IEEE 1394a-2000 prohibits using the same generation number
 228          * twice in a 60 second period. */
 229         if (time_before(jiffies, host->csr.gen_timestamp[next_gen] + 60 * HZ))
 230                 /* Wait 60 seconds from the last time this generation number was
 231                  * used. */
 232                 reset_delay = (60 * HZ) + host->csr.gen_timestamp[next_gen] - jiffies;
 233         else
 234                 /* Wait 1 second in case some other code wants to change the
 235                  * Config ROM in the near future. */
 236                 reset_delay = HZ;
 237
 238         PREPARE_DELAYED_WORK(&host->delayed_reset, delayed_reset_bus);
 239         schedule_delayed_work(&host->delayed_reset, reset_delay);
 240
 241         return 0;
 242 }