cxgb4/iw_cxgb4: use firmware ord/ird resource limits

Advertise a larger max read queue depth for qps, and gather the resource limits
from fw and use them to avoid exhaustinq all the resources.

Design:

cxgb4:

Obtain the max_ordird_qp and max_ird_adapter device params from FW
at init time and pass them up to the ULDs when they attach.  If these
parameters are not available, due to older firmware, then hard-code
the values based on the known values for older firmware.
iw_cxgb4:

Fix the c4iw_query_device() to report these correct values based on
adapter parameters.  ibv_query_device() will always return:

max_qp_rd_atom = max_qp_init_rd_atom = min(module_max, max_ordird_qp)
max_res_rd_atom = max_ird_adapter

Bump up the per qp max module option to 32, allowing it to be increased
by the user up to the device max of max_ordird_qp.  32 seems to be
sufficient to maximize throughput for streaming read benchmarks.

Fail connection setup if the negotiated IRD exhausts the available
adapter ird resources.  So the driver will track the amount of ird
resource in use and not send an RI_WR/INIT to FW that would reduce the
available ird resources below zero.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 25 insertions, 0 deletions

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4.h b/drivers/net/ethernet/chelsio/cxgb4/cxgb4.h
index f338a7fcebf7..46156210df34 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4.h
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4.h
@@ -310,6 +310,9 @@ struct adapter_params {
 
 	unsigned int ofldq_wr_cred;
 	bool ulptx_memwrite_dsgl;          /* use of T5 DSGL allowed */
+
+	unsigned int max_ordird_qp;       /* Max read depth per RDMA QP */
+	unsigned int max_ird_adapter;     /* Max read depth per adapter */
 };
 
 #include "t4fw_api.h"
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
index a7ce996630ed..767cbbaa3d1e 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
@@ -4113,6 +4113,8 @@ static void uld_attach(struct adapter *adap, unsigned int uld)
 	lli.sge_egrstatuspagesize = adap->sge.stat_len;
 	lli.sge_pktshift = adap->sge.pktshift;
 	lli.enable_fw_ofld_conn = adap->flags & FW_OFLD_CONN;
+	lli.max_ordird_qp = adap->params.max_ordird_qp;
+	lli.max_ird_adapter = adap->params.max_ird_adapter;
 	lli.ulptx_memwrite_dsgl = adap->params.ulptx_memwrite_dsgl;
 
 	handle = ulds[uld].add(&lli);
@@ -5877,6 +5879,22 @@ static int adap_init0(struct adapter *adap)
 		adap->vres.cq.size = val[3] - val[2] + 1;
 		adap->vres.ocq.start = val[4];
 		adap->vres.ocq.size = val[5] - val[4] + 1;
+
+		params[0] = FW_PARAM_DEV(MAXORDIRD_QP);
+		params[1] = FW_PARAM_DEV(MAXIRD_ADAPTER);
+		ret = t4_query_params(adap, 0, 0, 0, 2, params, val);
+		if (ret < 0) {
+			adap->params.max_ordird_qp = 8;
+			adap->params.max_ird_adapter = 32 * adap->tids.ntids;
+			ret = 0;
+		} else {
+			adap->params.max_ordird_qp = val[0];
+			adap->params.max_ird_adapter = val[1];
+		}
+		dev_info(adap->pdev_dev,
+			 "max_ordird_qp %d max_ird_adapter %d\n",
+			 adap->params.max_ordird_qp,
+			 adap->params.max_ird_adapter);
 	}
 	if (caps_cmd.iscsicaps) {
 		params[0] = FW_PARAM_PFVF(ISCSI_START);
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.h b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.h
index 962458f5d5b3..df1d9446768a 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.h
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.h
@@ -258,6 +258,8 @@ struct cxgb4_lld_info {
 	unsigned int pf;		     /* Physical Function we're using */
 	bool enable_fw_ofld_conn;            /* Enable connection through fw */
 					     /* WR */
+	unsigned int max_ordird_qp;          /* Max ORD/IRD depth per RDMA QP */
+	unsigned int max_ird_adapter;        /* Max IRD memory per adapter */
 	bool ulptx_memwrite_dsgl;            /* use of T5 DSGL allowed */
 };
 
diff --git a/drivers/net/ethernet/chelsio/cxgb4/t4fw_api.h b/drivers/net/ethernet/chelsio/cxgb4/t4fw_api.h
index 4a6ae4db7397..ff709e3b3e7e 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/t4fw_api.h
+++ b/drivers/net/ethernet/chelsio/cxgb4/t4fw_api.h
@@ -934,6 +934,8 @@ enum fw_params_param_dev {
 	FW_PARAMS_PARAM_DEV_FWREV = 0x0B,
 	FW_PARAMS_PARAM_DEV_TPREV = 0x0C,
 	FW_PARAMS_PARAM_DEV_CF = 0x0D,
+	FW_PARAMS_PARAM_DEV_MAXORDIRD_QP = 0x13, /* max supported QP IRD/ORD */
+	FW_PARAMS_PARAM_DEV_MAXIRD_ADAPTER = 0x14, /* max supported adap IRD */
 	FW_PARAMS_PARAM_DEV_ULPTX_MEMWRITE_DSGL = 0x17,
 };