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