firewire: sbp2: fix payload limit at S1600 and S3200
1394-2008 clause 16.3.4.1 (1394b-2002 clause 16.3.1.1) defines tighter
limits than 1394-2008 clause 6.2.2.3 (1394a-2000 clause 6.2.2.3).
Our previously too large limit doesn't matter though if the controller
reports its max_receive correctly.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/drivers/firewire/fw-sbp2.c b/drivers/firewire/fw-sbp2.c
index e88d506..ac80384 100644
--- a/drivers/firewire/fw-sbp2.c
+++ b/drivers/firewire/fw-sbp2.c
@@ -168,6 +168,7 @@
int address_high;
unsigned int workarounds;
unsigned int mgt_orb_timeout;
+ unsigned int max_payload;
int dont_block; /* counter for each logical unit */
int blocked; /* ditto */
@@ -1156,6 +1157,15 @@
sbp2_init_workarounds(tgt, model, firmware_revision);
+ /*
+ * At S100 we can do 512 bytes per packet, at S200 1024 bytes,
+ * and so on up to 4096 bytes. The SBP-2 max_payload field
+ * specifies the max payload size as 2 ^ (max_payload + 2), so
+ * if we set this to max_speed + 7, we get the right value.
+ */
+ tgt->max_payload = min(device->max_speed + 7, 10U);
+ tgt->max_payload = min(tgt->max_payload, device->card->max_receive - 1);
+
/* Do the login in a workqueue so we can easily reschedule retries. */
list_for_each_entry(lu, &tgt->lu_list, link)
sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
@@ -1434,7 +1444,6 @@
struct sbp2_logical_unit *lu = cmd->device->hostdata;
struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
struct sbp2_command_orb *orb;
- unsigned int max_payload;
int generation, retval = SCSI_MLQUEUE_HOST_BUSY;
/*
@@ -1462,17 +1471,9 @@
orb->done = done;
orb->cmd = cmd;
- orb->request.next.high = cpu_to_be32(SBP2_ORB_NULL);
- /*
- * At speed 100 we can do 512 bytes per packet, at speed 200,
- * 1024 bytes per packet etc. The SBP-2 max_payload field
- * specifies the max payload size as 2 ^ (max_payload + 2), so
- * if we set this to max_speed + 7, we get the right value.
- */
- max_payload = min(device->max_speed + 7,
- device->card->max_receive - 1);
+ orb->request.next.high = cpu_to_be32(SBP2_ORB_NULL);
orb->request.misc = cpu_to_be32(
- COMMAND_ORB_MAX_PAYLOAD(max_payload) |
+ COMMAND_ORB_MAX_PAYLOAD(lu->tgt->max_payload) |
COMMAND_ORB_SPEED(device->max_speed) |
COMMAND_ORB_NOTIFY);