firewire: core: simplify broadcast channel allocation
Stefan Richter [Tue, 10 Mar 2009 20:08:37 +0000 (21:08 +0100)]
fw-iso.c has channel allocation code now, use it.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

drivers/firewire/fw-card.c

index b3463b8..d63d0ed 100644 (file)
@@ -181,10 +181,6 @@ void fw_core_remove_descriptor(struct fw_descriptor *desc)
        mutex_unlock(&card_mutex);
 }
 
-/* ------------------------------------------------------------------ */
-/* Code to handle 1394a broadcast channel */
-
-#define THIRTY_TWO_CHANNELS (0xFFFFFFFFU)
 #define IRM_RETRIES 2
 
 /*
@@ -265,62 +261,18 @@ tryagain_w:
        return 0;
 }
 
-static void
-irm_allocate_broadcast(struct fw_device *irm_dev, struct device *locald)
+static void allocate_broadcast_channel(struct fw_card *card, int generation)
 {
-       u32 generation;
-       u32 node_id;
-       u32 max_speed;
-       u32 retries;
-       __be32 old_data;
-       __be32 lock_data[2];
-       int rcode;
-
-       /*
-        * The device we are updating is the IRM, so we must do
-        * some extra work.
-        */
-       retries = IRM_RETRIES;
-       generation = irm_dev->generation;
-       /* FIXME: do we need locking here? */
-       smp_rmb();
-       node_id = irm_dev->node_id;
-       max_speed = irm_dev->max_speed;
-
-       lock_data[0] = cpu_to_be32(THIRTY_TWO_CHANNELS);
-       lock_data[1] = cpu_to_be32(THIRTY_TWO_CHANNELS & ~1);
-tryagain:
-       old_data = lock_data[0];
-       rcode = fw_run_transaction(irm_dev->card, TCODE_LOCK_COMPARE_SWAP,
-                                  node_id, generation, max_speed,
-                                  CSR_REGISTER_BASE+CSR_CHANNELS_AVAILABLE_HI,
-                                  &lock_data[0], 8);
-       switch (rcode) {
-       case RCODE_BUSY:
-               if (retries--)
-                       goto tryagain;
-               /* fallthrough */
-       default:
-               fw_error("node %x: allocate broadcast channel failed (%x)\n",
-                        node_id, rcode);
-               return;
-
-       case RCODE_COMPLETE:
-               if (lock_data[0] == old_data)
-                       break;
-               if (retries--) {
-                       lock_data[1] = cpu_to_be32(be32_to_cpu(lock_data[0])&~1);
-                       goto tryagain;
-               }
-               fw_error("node %x: allocate broadcast channel failed: too many"
-                        " retries\n", node_id);
-               return;
+       int channel, bandwidth = 0;
+
+       fw_iso_resource_manage(card, generation, 1ULL << 31,
+                              &channel, &bandwidth, true);
+       if (channel == 31) {
+               card->is_irm = true;
+               device_for_each_child(card->device, NULL,
+                                     fw_irm_set_broadcast_channel_register);
        }
-       irm_dev->card->is_irm = true;
-       device_for_each_child(locald, NULL, fw_irm_set_broadcast_channel_register);
 }
-/* ------------------------------------------------------------------ */
-
 
 static const char gap_count_table[] = {
        63, 5, 7, 8, 10, 13, 16, 18, 21, 24, 26, 29, 32, 35, 37, 40
@@ -339,10 +291,11 @@ void fw_schedule_bm_work(struct fw_card *card, unsigned long delay)
 static void fw_card_bm_work(struct work_struct *work)
 {
        struct fw_card *card = container_of(work, struct fw_card, work.work);
-       struct fw_device *root_device, *irm_device, *local_device;
-       struct fw_node *root_node, *local_node, *irm_node;
+       struct fw_device *root_device;
+       struct fw_node *root_node;
        unsigned long flags;
-       int root_id, new_root_id, irm_id, gap_count, generation, grace, rcode;
+       int root_id, new_root_id, irm_id, local_id;
+       int gap_count, generation, grace, rcode;
        bool do_reset = false;
        bool root_device_is_running;
        bool root_device_is_cmc;
@@ -350,26 +303,22 @@ static void fw_card_bm_work(struct work_struct *work)
 
        spin_lock_irqsave(&card->lock, flags);
        card->is_irm = false;
-       local_node = card->local_node;
-       root_node  = card->root_node;
-       irm_node = card->irm_node;
 
-       if (local_node == NULL) {
+       if (card->local_node == NULL) {
                spin_unlock_irqrestore(&card->lock, flags);
                goto out_put_card;
        }
-       fw_node_get(local_node);
-       fw_node_get(root_node);
-       fw_node_get(irm_node);
 
        generation = card->generation;
+       root_node = card->root_node;
+       fw_node_get(root_node);
        root_device = root_node->data;
        root_device_is_running = root_device &&
                        atomic_read(&root_device->state) == FW_DEVICE_RUNNING;
        root_device_is_cmc = root_device && root_device->cmc;
-       root_id = root_node->node_id;
-       irm_device = irm_node->data;
-       local_device = local_node->data;
+       root_id  = root_node->node_id;
+       irm_id   = card->irm_node->node_id;
+       local_id = card->local_node->node_id;
 
        grace = time_after(jiffies, card->reset_jiffies + DIV_ROUND_UP(HZ, 8));
 
@@ -387,16 +336,15 @@ static void fw_card_bm_work(struct work_struct *work)
                 * next generation.
                 */
 
-               irm_id = irm_node->node_id;
-               if (!irm_node->link_on) {
-                       new_root_id = local_node->node_id;
+               if (!card->irm_node->link_on) {
+                       new_root_id = local_id;
                        fw_notify("IRM has link off, making local node (%02x) root.\n",
                                  new_root_id);
                        goto pick_me;
                }
 
                lock_data[0] = cpu_to_be32(0x3f);
-               lock_data[1] = cpu_to_be32(local_node->node_id);
+               lock_data[1] = cpu_to_be32(local_id);
 
                spin_unlock_irqrestore(&card->lock, flags);
 
@@ -411,12 +359,11 @@ static void fw_card_bm_work(struct work_struct *work)
 
                if (rcode == RCODE_COMPLETE &&
                    lock_data[0] != cpu_to_be32(0x3f)) {
-                       /* Somebody else is BM, let them do the work. */
-                       if (irm_id == local_node->node_id) {
-                               /* But we are IRM, so do irm-y things */
-                               irm_allocate_broadcast(irm_device,
-                                                      card->device);
-                       }
+
+                       /* Somebody else is BM.  Only act as IRM. */
+                       if (local_id == irm_id)
+                               allocate_broadcast_channel(card, generation);
+
                        goto out;
                }
 
@@ -429,7 +376,7 @@ static void fw_card_bm_work(struct work_struct *work)
                         * do a bus reset and pick the local node as
                         * root, and thus, IRM.
                         */
-                       new_root_id = local_node->node_id;
+                       new_root_id = local_id;
                        fw_notify("BM lock failed, making local node (%02x) root.\n",
                                  new_root_id);
                        goto pick_me;
@@ -456,7 +403,7 @@ static void fw_card_bm_work(struct work_struct *work)
                 * Either link_on is false, or we failed to read the
                 * config rom.  In either case, pick another root.
                 */
-               new_root_id = local_node->node_id;
+               new_root_id = local_id;
        } else if (!root_device_is_running) {
                /*
                 * If we haven't probed this device yet, bail out now
@@ -478,7 +425,7 @@ static void fw_card_bm_work(struct work_struct *work)
                 * successfully read the config rom, but it's not
                 * cycle master capable.
                 */
-               new_root_id = local_node->node_id;
+               new_root_id = local_id;
        }
 
  pick_me:
@@ -509,19 +456,14 @@ static void fw_card_bm_work(struct work_struct *work)
                          card->index, new_root_id, gap_count);
                fw_send_phy_config(card, new_root_id, generation, gap_count);
                fw_core_initiate_bus_reset(card, 1);
-       } else if (irm_node->node_id == local_node->node_id) {
-               /*
-                * We are IRM, so do irm-y things.
-                * There's no reason to do this if we're doing a reset. . .
-                * We'll be back.
-                */
-               irm_allocate_broadcast(irm_device, card->device);
+               /* Will allocate broadcast channel after the reset. */
+       } else {
+               if (local_id == irm_id)
+                       allocate_broadcast_channel(card, generation);
        }
 
  out:
        fw_node_put(root_node);
-       fw_node_put(local_node);
-       fw_node_put(irm_node);
  out_put_card:
        fw_card_put(card);
 }