Commit 647dcb5f authored by Ben Collins's avatar Ben Collins
Browse files

ieee1394: support for slow links or slow 1394b phy ports 



Add support for the following types of hardware:
 + nodes that have a link speed < PHY speed
 + 1394b PHYs that are less than S800 capable
 + 1394b/1394a adapter cable between two 1394b PHYs
Also, S1600 and S3200 are now supported if IEEE1394_SPEED_MAX is raised.

A probing function is added to nodemgr's config ROM fetching routine
which adjusts the allowable speed if an access problem was encountered.
Pros and Cons of the approach:
 + minimum code footprint to support this less widely used hardware
 + nearly no overhead for unaffected hardware
 - ineffective before nodemgr began to read the ROM of affected nodes
 - ineffective if ieee1394 is loaded with disable_nodemgr=1
The speed map CSRs which are published to the bus are not touched by the
patch.

Signed-off-by: default avatarStefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Hakan Ardo <hakan@debian.org>
Cc: Calculex <linux@calculex.com>
Cc: Robert J. Kosinski <robk@cmcherald.com>
Signed-off-by: default avatarBen Collins <bcollins@ubuntu.com>
parent 57fdb58f

drivers/ieee1394/eth1394.c

+2 −4
Original line number Diff line number Diff line
@@ -502,10 +502,8 @@ static void ether1394_reset_priv (struct net_device *dev, int set_mtu) 


	/* Determine speed limit */

	for (i = 0; i < host->node_count; i++)

		if (max_speed > host->speed_map[NODEID_TO_NODE(host->node_id) *

						64 + i])

			max_speed = host->speed_map[NODEID_TO_NODE(host->node_id) *

						    64 + i];

		if (max_speed > host->speed[i])

			max_speed = host->speed[i];

	priv->bc_sspd = max_speed;



	/* We'll use our maxpayload as the default mtu */

drivers/ieee1394/hosts.h

+6 −5
Original line number Diff line number Diff line
@@ -32,7 +32,8 @@ struct hpsb_host { 


	int node_count;     /* number of identified nodes on this bus */

	int selfid_count;   /* total number of SelfIDs received */

	int nodes_active; /* number of nodes that are actually active */

	int nodes_active;   /* number of nodes with active link layer */

	u8 speed[63];       /* speed between each node and local node */



	nodeid_t node_id;   /* node ID of this host */

	nodeid_t irm_id;    /* ID of this bus' isochronous resource manager */

drivers/ieee1394/ieee1394_core.c

+9 −5
Original line number Diff line number Diff line
@@ -285,9 +285,9 @@ static int check_selfids(struct hpsb_host *host) 


static void build_speed_map(struct hpsb_host *host, int nodecount)

{

	u8 speedcap[nodecount];

	u8 cldcnt[nodecount];

	u8 *map = host->speed_map;

	u8 *speedcap = host->speed;

	struct selfid *sid;

	struct ext_selfid *esid;

	int i, j, n;
@@ -354,6 +354,11 @@ static void build_speed_map(struct hpsb_host *host, int nodecount) 
			}

		}

	}



	/* assume maximum speed for 1394b PHYs, nodemgr will correct it */

	for (n = 0; n < nodecount; n++)

		if (speedcap[n] == 3)

			speedcap[n] = IEEE1394_SPEED_MAX;

}
@@ -554,11 +559,10 @@ int hpsb_send_packet(struct hpsb_packet *packet) 
		return 0;

	}



	if (packet->type == hpsb_async && packet->node_id != ALL_NODES) {

	if (packet->type == hpsb_async &&

	    NODEID_TO_NODE(packet->node_id) != ALL_NODES)

		packet->speed_code =

			host->speed_map[NODEID_TO_NODE(host->node_id) * 64

				       + NODEID_TO_NODE(packet->node_id)];

	}

			host->speed[NODEID_TO_NODE(packet->node_id)];



	dump_packet("send packet", packet->header, packet->header_size, packet->speed_code);

drivers/ieee1394/nodemgr.c

+58 −3
Original line number Diff line number Diff line
@@ -38,6 +38,7 @@ struct nodemgr_csr_info { 
	struct hpsb_host *host;

	nodeid_t nodeid;

	unsigned int generation;

	unsigned int speed_unverified:1;

};
@@ -57,23 +58,75 @@ static char *nodemgr_find_oui_name(int oui) 
	return NULL;

}



/*

 * Correct the speed map entry.  This is necessary

 *  - for nodes with link speed < phy speed,

 *  - for 1394b nodes with negotiated phy port speed < IEEE1394_SPEED_MAX.

 * A possible speed is determined by trial and error, using quadlet reads.

 */

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 ret;



	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;

		ret = hpsb_read(ci->host, ci->nodeid, ci->generation, addr,

				&q, sizeof(quadlet_t));

		if (ret)

			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 ret;

}



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;

	int i, ret;



	for (i = 1; ; i++) {

		ret = hpsb_read(ci->host, ci->nodeid, ci->generation, addr,

				buffer, length);

		if (!ret || i == 3)

		if (!ret) {

			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 && length == sizeof(quadlet_t)) {

			ret = nodemgr_check_speed(ci, addr, buffer);

			if (!ret)

				break;

		}

		if (msleep_interruptible(334))

			return -EINTR;

	}



	return ret;

}
@@ -1204,6 +1257,8 @@ static void nodemgr_node_scan_one(struct host_info *hi, 
	ci->host = host;

	ci->nodeid = nodeid;

	ci->generation = generation;

	ci->speed_unverified =

		host->speed[NODEID_TO_NODE(nodeid)] > IEEE1394_SPEED_100;



	/* We need to detect when the ConfigROM's generation has changed,

	 * so we only update the node's info when it needs to be.  */

drivers/ieee1394/sbp2.c

+1 −3
Original line number Diff line number Diff line
@@ -1664,10 +1664,8 @@ static int sbp2_max_speed_and_size(struct scsi_id_instance_data *scsi_id) 


	SBP2_DEBUG_ENTER();



	/* Initial setting comes from the hosts speed map */

	scsi_id->speed_code =

	    hi->host->speed_map[NODEID_TO_NODE(hi->host->node_id) * 64 +

				NODEID_TO_NODE(scsi_id->ne->nodeid)];

	    hi->host->speed[NODEID_TO_NODE(scsi_id->ne->nodeid)];



	/* Bump down our speed if the user requested it */

	if (scsi_id->speed_code > max_speed) {

CRA Git | Maintained and supported by SUSTech CRA and CCSE