static int nodemgr_bus_read(struct csr1212_csr *csr, u64 addr,
void *buffer, void *__ci)
{
struct nodemgr_csr_info *ci = (struct nodemgr_csr_info*)__ci;
int i, error;
for (i = 1; ; i++) {
error = hpsb_read(ci->host, ci->nodeid, ci->generation, addr,
buffer, 4);
if (!error) {
ci->speed_unverified = 0;
break;
}
/* Give up after 3rd failure. */
if (i == 3)
break;
/* The ieee1394_core guessed the node's speed capability from
* the self ID. Check whether a lower speed works. */
if (ci->speed_unverified) {
error = nodemgr_check_speed(ci, addr, buffer);
if (!error)
break;
}
if (msleep_interruptible(334))
return -EINTR;
}
return error;
}
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;
}
static int nodemgr_bus_read(struct csr1212_csr *csr, u64 addr, u16 length,
void *buffer, void *__ci)
{
struct nodemgr_csr_info *ci = (struct nodemgr_csr_info*)__ci;
int i, ret = 0;
for (i = 0; i < 3; i++) {
ret = hpsb_read(ci->host, ci->nodeid, ci->generation, addr,
buffer, length);
if (!ret)
break;
if (msleep_interruptible(334))
return -EINTR;
}
return ret;
}
