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.
  48                  * Reset generation field and do not issue a bus reset. */
  49                 CSR_SET_BUS_INFO_GENERATION(host->csr.rom,
  50                                             host->csr.generation);
  51                 return;
  52         }
  53
  54         host->csr.generation = generation;
  55
  56         host->update_config_rom = 0;
  57         if (host->driver->set_hw_config_rom)
  58                 host->driver->set_hw_config_rom(host,
  59                                                 host->csr.rom->bus_info_data);
  60
  61         host->csr.gen_timestamp[host->csr.generation] = jiffies;
  62         hpsb_reset_bus(host, SHORT_RESET);
  63 }
  64
  65 static int dummy_transmit_packet(struct hpsb_host *h, struct hpsb_packet *p)
  66 {
  67         return 0;
  68 }
  69
  70 static int dummy_devctl(struct hpsb_host *h, enum devctl_cmd c, int arg)
  71 {
  72         return -1;
  73 }
  74
  75 static int dummy_isoctl(struct hpsb_iso *iso, enum isoctl_cmd command,
  76                         unsigned long arg)
  77 {
  78         return -1;
  79 }
  80
  81 static struct hpsb_host_driver dummy_driver = {
  82         .transmit_packet = dummy_transmit_packet,
  83         .devctl =          dummy_devctl,
  84         .isoctl =          dummy_isoctl
  85 };
  86
  87 static int alloc_hostnum_cb(struct hpsb_host *host, void *__data)
  88 {
  89         int *hostnum = __data;
  90
  91         if (host->id == *hostnum)
  92                 return 1;
  93
  94         return 0;
  95 }
  96
  97 /*
  98  * The pending_packet_queue is special in that it's processed
  99  * from hardirq context too (such as hpsb_bus_reset()). Hence
 100  * split the lock class from the usual networking skb-head
 101  * lock class by using a separate key for it:
 102  */
 103 static struct lock_class_key pending_packet_queue_key;
 104
 105 static DEFINE_MUTEX(host_num_alloc);
 106
 107 /**
 108  * hpsb_alloc_host - allocate a new host controller.
 109  * @drv: the driver that will manage the host controller
 110  * @extra: number of extra bytes to allocate for the driver
 111  *
 112  * Allocate a &hpsb_host and initialize the general subsystem specific
 113  * fields.  If the driver needs to store per host data, as drivers
 114  * usually do, the amount of memory required can be specified by the
 115  * @extra parameter.  Once allocated, the driver should initialize the
 116  * driver specific parts, enable the controller and make it available
 117  * to the general subsystem using hpsb_add_host().
 118  *
 119  * Return Value: a pointer to the &hpsb_host if successful, %NULL if
 120  * no memory was available.
 121  */
 122 struct hpsb_host *hpsb_alloc_host(struct hpsb_host_driver *drv, size_t extra,
 123                                   struct device *dev)
 124 {
 125         struct hpsb_host *h;
 126         int i;
 127         int hostnum = 0;
 128
 129         h = kzalloc(sizeof(*h) + extra, GFP_KERNEL);
 130         if (!h)
 131                 return NULL;
 132
 133         h->csr.rom = csr1212_create_csr(&csr_bus_ops, CSR_BUS_INFO_SIZE, h);
 134         if (!h->csr.rom)
 135                 goto fail;
 136
 137         h->hostdata = h + 1;
 138         h->driver = drv;
 139
 140         skb_queue_head_init(&h->pending_packet_queue);
 141         lockdep_set_class(&h->pending_packet_queue.lock,
 142                            &pending_packet_queue_key);
 143         INIT_LIST_HEAD(&h->addr_space);
 144
 145         for (i = 2; i < 16; i++)
 146                 h->csr.gen_timestamp[i] = jiffies - 60 * HZ;
 147
 148         atomic_set(&h->generation, 0);
 149
 150         INIT_DELAYED_WORK(&h->delayed_reset, delayed_reset_bus);
 151
 152         init_timer(&h->timeout);
 153         h->timeout.data = (unsigned long) h;
 154         h->timeout.function = abort_timedouts;
 155         h->timeout_interval = HZ / 20; /* 50ms, half of minimum SPLIT_TIMEOUT */
 156
 157         h->topology_map = h->csr.topology_map + 3;
 158         h->speed_map = (u8 *)(h->csr.speed_map + 2);
 159
 160         mutex_lock(&host_num_alloc);
 161         while (nodemgr_for_each_host(&hostnum, alloc_hostnum_cb))
 162                 hostnum++;
 163         mutex_unlock(&host_num_alloc);
 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         if (device_register(&h->device))
 175                 goto fail;
 176         if (class_device_register(&h->class_dev)) {
 177                 device_unregister(&h->device);
 178                 goto fail;
 179         }
 180         get_device(&h->device);
 181
 182         return h;
 183
 184 fail:
 185         kfree(h);
 186         return NULL;
 187 }
 188
 189 int hpsb_add_host(struct hpsb_host *host)
 190 {
 191         if (hpsb_default_host_entry(host))
 192                 return -ENOMEM;
 193         hpsb_add_extra_config_roms(host);
 194         highlevel_add_host(host);
 195         return 0;
 196 }
 197
 198 void hpsb_resume_host(struct hpsb_host *host)
 199 {
 200         if (host->driver->set_hw_config_rom)
 201                 host->driver->set_hw_config_rom(host,
 202                                                 host->csr.rom->bus_info_data);
 203         host->driver->devctl(host, RESET_BUS, SHORT_RESET);
 204 }
 205
 206 void hpsb_remove_host(struct hpsb_host *host)
 207 {
 208         host->is_shutdown = 1;
 209
 210         cancel_delayed_work(&host->delayed_reset);
 211         flush_scheduled_work();
 212
 213         host->driver = &dummy_driver;
 214         highlevel_remove_host(host);
 215         hpsb_remove_extra_config_roms(host);
 216
 217         class_device_unregister(&host->class_dev);
 218         device_unregister(&host->device);
 219 }
 220
 221 int hpsb_update_config_rom_image(struct hpsb_host *host)
 222 {
 223         unsigned long reset_delay;
 224         int next_gen = host->csr.generation + 1;
 225
 226         if (!host->update_config_rom)
 227                 return -EINVAL;
 228
 229         if (next_gen > 0xf)
 230                 next_gen = 2;
 231
 232         /* Stop the delayed interrupt, we're about to change the config rom and
 233          * it would be a waste to do a bus reset twice. */
 234         cancel_delayed_work(&host->delayed_reset);
 235
 236         /* IEEE 1394a-2000 prohibits using the same generation number
 237          * twice in a 60 second period. */
 238         if (time_before(jiffies, host->csr.gen_timestamp[next_gen] + 60 * HZ))
 239                 /* Wait 60 seconds from the last time this generation number was
 240                  * used. */
 241                 reset_delay =
 242                         (60 * HZ) + host->csr.gen_timestamp[next_gen] - jiffies;
 243         else
 244                 /* Wait 1 second in case some other code wants to change the
 245                  * Config ROM in the near future. */
 246                 reset_delay = HZ;
 247
 248         PREPARE_DELAYED_WORK(&host->delayed_reset, delayed_reset_bus);
 249         schedule_delayed_work(&host->delayed_reset, reset_delay);
 250
 251         return 0;
 252 }