diff options
| -rw-r--r-- | drivers/ieee1394/nodemgr.c | 42 |
1 files changed, 32 insertions, 10 deletions
diff --git a/drivers/ieee1394/nodemgr.c b/drivers/ieee1394/nodemgr.c index f7c3dbaf580..0ea37b1bccb 100644 --- a/drivers/ieee1394/nodemgr.c +++ b/drivers/ieee1394/nodemgr.c @@ -1349,6 +1349,33 @@ static void nodemgr_update_pdrv(struct node_entry *ne) } +/* Write the BROADCAST_CHANNEL as per IEEE1394a 8.3.2.3.11 and 8.4.2.3. This + * seems like an optional service but in the end it is practically mandatory + * as a consequence of these clauses. + * + * Note that we cannot do a broadcast write to all nodes at once because some + * pre-1394a devices would hang. */ +static void nodemgr_irm_write_bc(struct node_entry *ne, int generation) +{ + const u64 bc_addr = (CSR_REGISTER_BASE | CSR_BROADCAST_CHANNEL); + quadlet_t bc_remote, bc_local; + int ret; + + if (!ne->host->is_irm || ne->generation != generation || + ne->nodeid == ne->host->node_id) + return; + + bc_local = cpu_to_be32(ne->host->csr.broadcast_channel); + + /* Check if the register is implemented and 1394a compliant. */ + ret = hpsb_read(ne->host, ne->nodeid, generation, bc_addr, &bc_remote, + sizeof(bc_remote)); + if (!ret && bc_remote & cpu_to_be32(0x80000000) && + bc_remote != bc_local) + hpsb_node_write(ne, bc_addr, &bc_local, sizeof(bc_local)); +} + + static void nodemgr_probe_ne(struct host_info *hi, struct node_entry *ne, int generation) { struct device *dev; @@ -1360,6 +1387,8 @@ static void nodemgr_probe_ne(struct host_info *hi, struct node_entry *ne, int ge if (!dev) return; + nodemgr_irm_write_bc(ne, generation); + /* If "needs_probe", then this is either a new or changed node we * rescan totally. If the generation matches for an existing node * (one that existed prior to the bus reset) we send update calls @@ -1431,9 +1460,7 @@ static int nodemgr_send_resume_packet(struct hpsb_host *host) return ret; } -/* Because we are a 1394a-2000 compliant IRM, we need to inform all the other - * nodes of the broadcast channel. (Really we're only setting the validity - * bit). Other IRM responsibilities go in here as well. */ +/* Perform a few high-level IRM responsibilities. */ static int nodemgr_do_irm_duties(struct hpsb_host *host, int cycles) { quadlet_t bc; @@ -1442,13 +1469,8 @@ static int nodemgr_do_irm_duties(struct hpsb_host *host, int cycles) if (!host->is_irm || host->irm_id == (nodeid_t)-1) return 1; - host->csr.broadcast_channel |= 0x40000000; /* set validity bit */ - - bc = cpu_to_be32(host->csr.broadcast_channel); - - hpsb_write(host, LOCAL_BUS | ALL_NODES, get_hpsb_generation(host), - (CSR_REGISTER_BASE | CSR_BROADCAST_CHANNEL), - &bc, sizeof(quadlet_t)); + /* We are a 1394a-2000 compliant IRM. Set the validity bit. */ + host->csr.broadcast_channel |= 0x40000000; /* If there is no bus manager then we should set the root node's * force_root bit to promote bus stability per the 1394 |