RDMA/cxgb4: Limit MAXBURST EQ context field to 256B

MAXBURST cannot exceed 256B for on-chip queues.  With a 512B MAXBURST,
we can lock up the chip.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Cc: <stable@kernel.org>
Signed-off-by: Roland Dreier <roland@purestorage.com>

drivers/infiniband/hw/cxgb4/qp.c

@@ -220,7 +220,7 @@ static int create_qp(struct c4iw_rdev *rdev, struct t4_wq *wq,
 		V_FW_RI_RES_WR_DCAEN(0) |
 		V_FW_RI_RES_WR_DCACPU(0) |
 		V_FW_RI_RES_WR_FBMIN(2) |
-		V_FW_RI_RES_WR_FBMAX(3) |
+		V_FW_RI_RES_WR_FBMAX(2) |
 		V_FW_RI_RES_WR_CIDXFTHRESHO(0) |
 		V_FW_RI_RES_WR_CIDXFTHRESH(0) |
 		V_FW_RI_RES_WR_EQSIZE(eqsize));
@@ -243,7 +243,7 @@ static int create_qp(struct c4iw_rdev *rdev, struct t4_wq *wq,
 		V_FW_RI_RES_WR_DCAEN(0) |
 		V_FW_RI_RES_WR_DCACPU(0) |
 		V_FW_RI_RES_WR_FBMIN(2) |
-		V_FW_RI_RES_WR_FBMAX(3) |
+		V_FW_RI_RES_WR_FBMAX(2) |
 		V_FW_RI_RES_WR_CIDXFTHRESHO(0) |
 		V_FW_RI_RES_WR_CIDXFTHRESH(0) |
 		V_FW_RI_RES_WR_EQSIZE(eqsize));