3 files changed, 177 insertions, 6 deletions

diff --git a/drivers/firewire/fw-card.c b/drivers/firewire/fw-card.c
index 08a7e18526ee..f2b363ea443e 100644
--- a/drivers/firewire/fw-card.c
+++ b/drivers/firewire/fw-card.c
@@ -181,6 +181,147 @@ 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
+
+/*
+ * The abi is set by device_for_each_child(), even though we have no use
+ * for data, nor do we have a meaningful return value.
+ */
+int fw_irm_set_broadcast_channel_register(struct device *dev, void *data)
+{
+        struct fw_device *d;
+        int rcode;
+        int node_id;
+        int max_speed;
+        int retries;
+        int generation;
+        __be32 regval;
+        struct fw_card *card;
+
+        d = fw_device(dev);
+        /* FIXME: do we need locking here? */
+        generation = d->generation;
+        smp_rmb(); /* Ensure generation is at least as old as node_id */
+        node_id = d->node_id;
+        max_speed = d->max_speed;
+        retries = IRM_RETRIES;
+        card = d->card;
+tryagain_r:
+        rcode = fw_run_transaction(card, TCODE_READ_QUADLET_REQUEST,
+                                   node_id, generation, max_speed,
+                                   CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL,
+                                   &regval, 4);
+        switch (rcode) {
+        case RCODE_BUSY:
+                if (retries--)
+                        goto tryagain_r;
+                fw_notify("node %x read broadcast channel busy\n",
+                          node_id);
+                return 0;
+
+        default:
+                fw_notify("node %x read broadcast channel failed %x\n",
+                          node_id, rcode);
+                return 0;
+
+        case RCODE_COMPLETE:
+                /*
+                 * Paranoid reporting of nonstandard broadcast channel
+                 * contents goes here
+                 */
+                if (regval != cpu_to_be32(BROADCAST_CHANNEL_INITIAL))
+                        return 0;
+                break;
+        }
+        retries = IRM_RETRIES;
+        regval = cpu_to_be32(BROADCAST_CHANNEL_INITIAL |
+                             BROADCAST_CHANNEL_VALID);
+tryagain_w:
+        rcode = fw_run_transaction(card,
+                        TCODE_WRITE_QUADLET_REQUEST, node_id,
+                        generation, max_speed,
+                        CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL,
+                        &regval, 4);
+        switch (rcode) {
+        case RCODE_BUSY:
+                if (retries--)
+                        goto tryagain_w;
+                fw_notify("node %x write broadcast channel busy\n",
+                          node_id);
+                return 0;
+
+        default:
+                fw_notify("node %x write broadcast channel failed %x\n",
+                          node_id, rcode);
+                return 0;
+
+        case RCODE_COMPLETE:
+                return 0;
+        }
+        return 0;
+}
+
+static void
+irm_allocate_broadcast(struct fw_device *irm_dev, struct device *locald)
+{
+        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;
+        }
+        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
 };
@@ -198,8 +339,8 @@ 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;
-        struct fw_node *root_node, *local_node;
+        struct fw_device *root_device, *irm_device, *local_device;
+        struct fw_node *root_node, *local_node, *irm_node;
         unsigned long flags;
         int root_id, new_root_id, irm_id, gap_count, generation, grace, rcode;
         bool do_reset = false;
@@ -208,8 +349,10 @@ static void fw_card_bm_work(struct work_struct *work)
         __be32 lock_data[2];
 
         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) {
                 spin_unlock_irqrestore(&card->lock, flags);
@@ -217,6 +360,7 @@ static void fw_card_bm_work(struct work_struct *work)
         }
         fw_node_get(local_node);
         fw_node_get(root_node);
+        fw_node_get(irm_node);
 
         generation = card->generation;
         root_device = root_node->data;
@@ -225,7 +369,8 @@ static void fw_card_bm_work(struct work_struct *work)
         root_device_is_cmc = root_device && root_device->cmc;
         root_id = root_node->node_id;
         grace = time_after(jiffies, card->reset_jiffies + DIV_ROUND_UP(HZ, 10));
-
+        irm_device = irm_node->data;
+        local_device = local_node->data;
         if (is_next_generation(generation, card->bm_generation) ||
             (card->bm_generation != generation && grace)) {
                 /*
@@ -240,8 +385,8 @@ static void fw_card_bm_work(struct work_struct *work)
                  * next generation.
                  */
 
-                irm_id = card->irm_node->node_id;
-                if (!card->irm_node->link_on) {
+                irm_id = irm_node->node_id;
+                if (!irm_node->link_on) {
                         new_root_id = local_node->node_id;
                         fw_notify("IRM has link off, making local node (%02x) root.\n",
                                   new_root_id);
@@ -263,9 +408,15 @@ static void fw_card_bm_work(struct work_struct *work)
                         goto out;
 
                 if (rcode == RCODE_COMPLETE &&
-                    lock_data[0] != cpu_to_be32(0x3f))
+                    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);
+                        }
                         goto out;
+                }
 
                 spin_lock_irqsave(&card->lock, flags);
 
@@ -357,10 +508,19 @@ 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);
         }
+
  out:
         fw_node_put(root_node);
         fw_node_put(local_node);
+        fw_node_put(irm_node);
  out_put_card:
         fw_card_put(card);
 }
diff --git a/drivers/firewire/fw-device.c b/drivers/firewire/fw-device.c
index 633e44de5d1a..a40444e8eb20 100644
--- a/drivers/firewire/fw-device.c
+++ b/drivers/firewire/fw-device.c
@@ -849,6 +849,9 @@ static void fw_device_init(struct work_struct *work)
                                   device->config_rom[3], device->config_rom[4],
                                   1 << device->max_speed);
                 device->config_rom_retries = 0;
+                if (device->card->is_irm)
+                        fw_irm_set_broadcast_channel_register(&device->device,
+                                                              NULL);
         }
 
         /*
diff --git a/drivers/firewire/fw-transaction.h b/drivers/firewire/fw-transaction.h
index eed2e295eb3c..f90f09c05833 100644
--- a/drivers/firewire/fw-transaction.h
+++ b/drivers/firewire/fw-transaction.h
@@ -230,6 +230,11 @@ struct fw_card {
         u8 color; /* must be u8 to match the definition in struct fw_node */
         int gap_count;
         bool beta_repeaters_present;
+        /*
+         * Set if the local device is the IRM and the broadcast channel
+         * was allocated.
+         */
+        bool is_irm;
 
         int index;
 
@@ -438,4 +443,7 @@ void fw_core_handle_bus_reset(struct fw_card *card, int node_id,
 void fw_core_handle_request(struct fw_card *card, struct fw_packet *request);
 void fw_core_handle_response(struct fw_card *card, struct fw_packet *packet);
 
+extern int fw_irm_set_broadcast_channel_register(struct device *dev,
+                                                 void *data);
+
 #endif /* __fw_transaction_h */