firewire: core: integrate software-forced bus resets with bus management
[pandora-kernel.git] / drivers / firewire / core-card.c
index d0f15c2..2bb5c03 100644 (file)
@@ -204,17 +204,62 @@ void fw_core_remove_descriptor(struct fw_descriptor *desc)
 }
 EXPORT_SYMBOL(fw_core_remove_descriptor);
 
+static int reset_bus(struct fw_card *card, bool short_reset)
+{
+       int reg = short_reset ? 5 : 1;
+       int bit = short_reset ? PHY_BUS_SHORT_RESET : PHY_BUS_RESET;
+
+       return card->driver->update_phy_reg(card, reg, 0, bit);
+}
+
+void fw_schedule_bus_reset(struct fw_card *card, bool delayed, bool short_reset)
+{
+       /* We don't try hard to sort out requests of long vs. short resets. */
+       card->br_short = short_reset;
+
+       /* Use an arbitrary short delay to combine multiple reset requests. */
+       fw_card_get(card);
+       if (!schedule_delayed_work(&card->br_work,
+                                  delayed ? DIV_ROUND_UP(HZ, 100) : 0))
+               fw_card_put(card);
+}
+EXPORT_SYMBOL(fw_schedule_bus_reset);
+
+static void br_work(struct work_struct *work)
+{
+       struct fw_card *card = container_of(work, struct fw_card, br_work.work);
+
+       /* Delay for 2s after last reset per IEEE 1394 clause 8.2.1. */
+       if (card->reset_jiffies != 0 &&
+           time_is_after_jiffies(card->reset_jiffies + 2 * HZ)) {
+               if (!schedule_delayed_work(&card->br_work, 2 * HZ))
+                       fw_card_put(card);
+               return;
+       }
+
+       fw_send_phy_config(card, FW_PHY_CONFIG_NO_NODE_ID, card->generation,
+                          FW_PHY_CONFIG_CURRENT_GAP_COUNT);
+       reset_bus(card, card->br_short);
+       fw_card_put(card);
+}
+
 static void allocate_broadcast_channel(struct fw_card *card, int generation)
 {
        int channel, bandwidth = 0;
 
-       fw_iso_resource_manage(card, generation, 1ULL << 31, &channel,
-                              &bandwidth, true, card->bm_transaction_data);
-       if (channel == 31) {
+       if (!card->broadcast_channel_allocated) {
+               fw_iso_resource_manage(card, generation, 1ULL << 31,
+                                      &channel, &bandwidth, true,
+                                      card->bm_transaction_data);
+               if (channel != 31) {
+                       fw_notify("failed to allocate broadcast channel\n");
+                       return;
+               }
                card->broadcast_channel_allocated = true;
-               device_for_each_child(card->device, (void *)(long)generation,
-                                     fw_device_set_broadcast_channel);
        }
+
+       device_for_each_child(card->device, (void *)(long)generation,
+                             fw_device_set_broadcast_channel);
 }
 
 static const char gap_count_table[] = {
@@ -224,26 +269,25 @@ static const char gap_count_table[] = {
 void fw_schedule_bm_work(struct fw_card *card, unsigned long delay)
 {
        fw_card_get(card);
-       if (!schedule_delayed_work(&card->work, delay))
+       if (!schedule_delayed_work(&card->bm_work, delay))
                fw_card_put(card);
 }
 
-static void fw_card_bm_work(struct work_struct *work)
+static void bm_work(struct work_struct *work)
 {
-       struct fw_card *card = container_of(work, struct fw_card, work.work);
+       struct fw_card *card = container_of(work, struct fw_card, bm_work.work);
        struct fw_device *root_device;
        struct fw_node *root_node;
-       unsigned long flags;
-       int root_id, new_root_id, irm_id, local_id;
+       int root_id, new_root_id, irm_id, bm_id, local_id;
        int gap_count, generation, grace, rcode;
        bool do_reset = false;
        bool root_device_is_running;
        bool root_device_is_cmc;
 
-       spin_lock_irqsave(&card->lock, flags);
+       spin_lock_irq(&card->lock);
 
        if (card->local_node == NULL) {
-               spin_unlock_irqrestore(&card->lock, flags);
+               spin_unlock_irq(&card->lock);
                goto out_put_card;
        }
 
@@ -260,7 +304,8 @@ static void fw_card_bm_work(struct work_struct *work)
 
        grace = time_after(jiffies, card->reset_jiffies + DIV_ROUND_UP(HZ, 8));
 
-       if (is_next_generation(generation, card->bm_generation) ||
+       if ((is_next_generation(generation, card->bm_generation) &&
+            !card->bm_abdicate) ||
            (card->bm_generation != generation && grace)) {
                /*
                 * This first step is to figure out who is IRM and
@@ -284,21 +329,26 @@ static void fw_card_bm_work(struct work_struct *work)
                card->bm_transaction_data[0] = cpu_to_be32(0x3f);
                card->bm_transaction_data[1] = cpu_to_be32(local_id);
 
-               spin_unlock_irqrestore(&card->lock, flags);
+               spin_unlock_irq(&card->lock);
 
                rcode = fw_run_transaction(card, TCODE_LOCK_COMPARE_SWAP,
                                irm_id, generation, SCODE_100,
                                CSR_REGISTER_BASE + CSR_BUS_MANAGER_ID,
-                               card->bm_transaction_data,
-                               sizeof(card->bm_transaction_data));
+                               card->bm_transaction_data, 8);
 
                if (rcode == RCODE_GENERATION)
                        /* Another bus reset, BM work has been rescheduled. */
                        goto out;
 
-               if (rcode == RCODE_COMPLETE &&
-                   card->bm_transaction_data[0] != cpu_to_be32(0x3f)) {
+               bm_id = be32_to_cpu(card->bm_transaction_data[0]);
+
+               spin_lock_irq(&card->lock);
+               if (rcode == RCODE_COMPLETE && generation == card->generation)
+                       card->bm_node_id =
+                           bm_id == 0x3f ? local_id : 0xffc0 | bm_id;
+               spin_unlock_irq(&card->lock);
 
+               if (rcode == RCODE_COMPLETE && bm_id != 0x3f) {
                        /* Somebody else is BM.  Only act as IRM. */
                        if (local_id == irm_id)
                                allocate_broadcast_channel(card, generation);
@@ -316,7 +366,7 @@ static void fw_card_bm_work(struct work_struct *work)
                        goto out;
                }
 
-               spin_lock_irqsave(&card->lock, flags);
+               spin_lock_irq(&card->lock);
 
                if (rcode != RCODE_COMPLETE) {
                        /*
@@ -335,7 +385,7 @@ static void fw_card_bm_work(struct work_struct *work)
                 * We weren't BM in the last generation, and the last
                 * bus reset is less than 125ms ago.  Reschedule this job.
                 */
-               spin_unlock_irqrestore(&card->lock, flags);
+               spin_unlock_irq(&card->lock);
                fw_schedule_bm_work(card, DIV_ROUND_UP(HZ, 8));
                goto out;
        }
@@ -358,14 +408,12 @@ static void fw_card_bm_work(struct work_struct *work)
                 * If we haven't probed this device yet, bail out now
                 * and let's try again once that's done.
                 */
-               spin_unlock_irqrestore(&card->lock, flags);
+               spin_unlock_irq(&card->lock);
                goto out;
        } else if (root_device_is_cmc) {
                /*
-                * FIXME: I suppose we should set the cmstr bit in the
-                * STATE_CLEAR register of this node, as described in
-                * 1394-1995, 8.4.2.6.  Also, send out a force root
-                * packet for this node.
+                * We will send out a force root packet for this
+                * node as part of the gap count optimization.
                 */
                new_root_id = root_id;
        } else {
@@ -398,19 +446,33 @@ static void fw_card_bm_work(struct work_struct *work)
            (card->gap_count != gap_count || new_root_id != root_id))
                do_reset = true;
 
-       spin_unlock_irqrestore(&card->lock, flags);
+       spin_unlock_irq(&card->lock);
 
        if (do_reset) {
                fw_notify("phy config: card %d, new root=%x, gap_count=%d\n",
                          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);
+               reset_bus(card, true);
                /* Will allocate broadcast channel after the reset. */
-       } else {
-               if (local_id == irm_id)
-                       allocate_broadcast_channel(card, generation);
+               goto out;
        }
 
+       if (root_device_is_cmc) {
+               /*
+                * Make sure that the cycle master sends cycle start packets.
+                */
+               card->bm_transaction_data[0] = cpu_to_be32(CSR_STATE_BIT_CMSTR);
+               rcode = fw_run_transaction(card, TCODE_WRITE_QUADLET_REQUEST,
+                               root_id, generation, SCODE_100,
+                               CSR_REGISTER_BASE + CSR_STATE_SET,
+                               card->bm_transaction_data, 4);
+               if (rcode == RCODE_GENERATION)
+                       goto out;
+       }
+
+       if (local_id == irm_id)
+               allocate_broadcast_channel(card, generation);
+
  out:
        fw_node_put(root_node);
  out_put_card:
@@ -442,7 +504,8 @@ void fw_card_initialize(struct fw_card *card,
 
        card->local_node = NULL;
 
-       INIT_DELAYED_WORK(&card->work, fw_card_bm_work);
+       INIT_DELAYED_WORK(&card->br_work, br_work);
+       INIT_DELAYED_WORK(&card->bm_work, bm_work);
 }
 EXPORT_SYMBOL(fw_card_initialize);
 
@@ -468,7 +531,6 @@ int fw_card_add(struct fw_card *card,
 }
 EXPORT_SYMBOL(fw_card_add);
 
-
 /*
  * The next few functions implement a dummy driver that is used once a card
  * driver shuts down an fw_card.  This allows the driver to cleanly unload,
@@ -484,6 +546,11 @@ static int dummy_enable(struct fw_card *card,
        return -1;
 }
 
+static int dummy_read_phy_reg(struct fw_card *card, int address)
+{
+       return -ENODEV;
+}
+
 static int dummy_update_phy_reg(struct fw_card *card, int address,
                                int clear_bits, int set_bits)
 {
@@ -524,6 +591,7 @@ static int dummy_enable_phys_dma(struct fw_card *card,
 
 static const struct fw_card_driver dummy_driver_template = {
        .enable          = dummy_enable,
+       .read_phy_reg    = dummy_read_phy_reg,
        .update_phy_reg  = dummy_update_phy_reg,
        .set_config_rom  = dummy_set_config_rom,
        .send_request    = dummy_send_request,
@@ -545,7 +613,7 @@ void fw_core_remove_card(struct fw_card *card)
 
        card->driver->update_phy_reg(card, 4,
                                     PHY_LINK_ACTIVE | PHY_CONTENDER, 0);
-       fw_core_initiate_bus_reset(card, 1);
+       fw_schedule_bus_reset(card, false, true);
 
        mutex_lock(&card_mutex);
        list_del_init(&card->link);
@@ -565,12 +633,3 @@ void fw_core_remove_card(struct fw_card *card)
        WARN_ON(!list_empty(&card->transaction_list));
 }
 EXPORT_SYMBOL(fw_core_remove_card);
-
-int fw_core_initiate_bus_reset(struct fw_card *card, int short_reset)
-{
-       int reg = short_reset ? 5 : 1;
-       int bit = short_reset ? PHY_BUS_SHORT_RESET : PHY_BUS_RESET;
-
-       return card->driver->update_phy_reg(card, reg, 0, bit);
-}
-EXPORT_SYMBOL(fw_core_initiate_bus_reset);