/* same as hpsb_get_tlabel, except that it returns immediately */
static int hpsb_get_tlabel_atomic(struct hpsb_packet *packet)
{
unsigned long flags, *tp;
u8 *next;
int tlabel, n = NODEID_TO_NODE(packet->node_id);
/* Broadcast transactions are complete once the request has been sent.
* Use the same transaction label for all broadcast transactions. */
if (unlikely(n == ALL_NODES)) {
packet->tlabel = 0;
return 0;
}
tp = packet->host->tl_pool[n].map;
next = &packet->host->next_tl[n];
spin_lock_irqsave(&hpsb_tlabel_lock, flags);
tlabel = find_next_zero_bit(tp, 64, *next);
if (tlabel > 63)
tlabel = find_first_zero_bit(tp, 64);
if (tlabel > 63) {
spin_unlock_irqrestore(&hpsb_tlabel_lock, flags);
return -EAGAIN;
}
__set_bit(tlabel, tp);
*next = (tlabel + 1) & 63;
spin_unlock_irqrestore(&hpsb_tlabel_lock, flags);
packet->tlabel = tlabel;
return 0;
}
/**
* hpsb_get_tlabel - allocate a transaction label
* @packet: the packet who's tlabel/tpool we set
*
* Every asynchronous transaction on the 1394 bus needs a transaction
* label to match the response to the request. This label has to be
* different from any other transaction label in an outstanding request to
* the same node to make matching possible without ambiguity.
*
* There are 64 different tlabels, so an allocated tlabel has to be freed
* with hpsb_free_tlabel() after the transaction is complete (unless it's
* reused again for the same target node).
*
* Return value: Zero on success, otherwise non-zero. A non-zero return
* generally means there are no available tlabels. If this is called out
* of interrupt or atomic context, then it will sleep until can return a
* tlabel.
*/
int hpsb_get_tlabel(struct hpsb_packet *packet)
{
unsigned long flags;
struct hpsb_tlabel_pool *tp;
int n = NODEID_TO_NODE(packet->node_id);
if (unlikely(n == ALL_NODES))
return 0;
tp = &packet->host->tpool[n];
if (irqs_disabled() || in_atomic()) {
if (down_trylock(&tp->count))
return 1;
} else {
down(&tp->count);
}
spin_lock_irqsave(&tp->lock, flags);
packet->tlabel = find_next_zero_bit(tp->pool, 64, tp->next);
if (packet->tlabel > 63)
packet->tlabel = find_first_zero_bit(tp->pool, 64);
tp->next = (packet->tlabel + 1) % 64;
/* Should _never_ happen */
BUG_ON(test_and_set_bit(packet->tlabel, tp->pool));
tp->allocations++;
spin_unlock_irqrestore(&tp->lock, flags);
return 0;
}
static int nodemgr_check_speed(struct nodemgr_csr_info *ci, u64 addr,
quadlet_t *buffer)
{
quadlet_t q;
u8 i, *speed, old_speed, good_speed;
int error;
speed = &(ci->host->speed[NODEID_TO_NODE(ci->nodeid)]);
old_speed = *speed;
good_speed = IEEE1394_SPEED_MAX + 1;
/* Try every speed from S100 to old_speed.
* If we did it the other way around, a too low speed could be caught
* if the retry succeeded for some other reason, e.g. because the link
* just finished its initialization. */
for (i = IEEE1394_SPEED_100; i <= old_speed; i++) {
*speed = i;
error = hpsb_read(ci->host, ci->nodeid, ci->generation, addr,
&q, 4);
if (error)
break;
*buffer = q;
good_speed = i;
}
if (good_speed <= IEEE1394_SPEED_MAX) {
HPSB_DEBUG("Speed probe of node " NODE_BUS_FMT " yields %s",
NODE_BUS_ARGS(ci->host, ci->nodeid),
hpsb_speedto_str[good_speed]);
*speed = good_speed;
ci->speed_unverified = 0;
return 0;
}
*speed = old_speed;
return error;
}
/**
* hpsb_free_tlabel - free an allocated transaction label
* @packet: packet whose tlabel and tl_pool needs to be cleared
*
* Frees the transaction label allocated with hpsb_get_tlabel(). The
* tlabel has to be freed after the transaction is complete (i.e. response
* was received for a split transaction or packet was sent for a unified
* transaction).
*
* A tlabel must not be freed twice.
*/
void hpsb_free_tlabel(struct hpsb_packet *packet)
{
unsigned long flags, *tp;
int tlabel, n = NODEID_TO_NODE(packet->node_id);
if (unlikely(n == ALL_NODES))
return;
tp = packet->host->tl_pool[n].map;
tlabel = packet->tlabel;
BUG_ON(tlabel > 63 || tlabel < 0);
spin_lock_irqsave(&hpsb_tlabel_lock, flags);
BUG_ON(!__test_and_clear_bit(tlabel, tp));
spin_unlock_irqrestore(&hpsb_tlabel_lock, flags);
wake_up_interruptible(&tlabel_wq);
}
/**
* hpsb_free_tlabel - free an allocated transaction label
* @packet: packet whos tlabel/tpool needs to be cleared
*
* Frees the transaction label allocated with hpsb_get_tlabel(). The
* tlabel has to be freed after the transaction is complete (i.e. response
* was received for a split transaction or packet was sent for a unified
* transaction).
*
* A tlabel must not be freed twice.
*/
void hpsb_free_tlabel(struct hpsb_packet *packet)
{
unsigned long flags;
struct hpsb_tlabel_pool *tp;
int n = NODEID_TO_NODE(packet->node_id);
if (unlikely(n == ALL_NODES))
return;
tp = &packet->host->tpool[n];
BUG_ON(packet->tlabel > 63 || packet->tlabel < 0);
spin_lock_irqsave(&tp->lock, flags);
BUG_ON(!test_and_clear_bit(packet->tlabel, tp->pool));
spin_unlock_irqrestore(&tp->lock, flags);
up(&tp->count);
}
