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From: Selvin Xavier <selvin.xavier@broadcom.com>
To: dledford@redhat.com, linux-rdma@vger.kernel.org
Cc: netdev@vger.kernel.org,
	Selvin Xavier <selvin.xavier@broadcom.com>,
	Eddie Wai <eddie.wai@broadcom.com>,
	Devesh Sharma <devesh.sharma@broadcom.com>,
	Somnath Kotur <somnath.kotur@broadcom.com>,
	Sriharsha Basavapatna <sriharsha.basavapatna@broadcom.com>
Subject: [PATCH V2  15/22] bnxt_re: Support post_recv
Date: Thu,  8 Dec 2016 22:48:09 -0800	[thread overview]
Message-ID: <1481266096-23331-16-git-send-email-selvin.xavier@broadcom.com> (raw)
In-Reply-To: <1481266096-23331-1-git-send-email-selvin.xavier@broadcom.com>

Enables the fastpath verb ib_post_recv.

Signed-off-by: Eddie Wai <eddie.wai@broadcom.com>
Signed-off-by: Devesh Sharma <devesh.sharma@broadcom.com>
Signed-off-by: Somnath Kotur <somnath.kotur@broadcom.com>
Signed-off-by: Sriharsha Basavapatna <sriharsha.basavapatna@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
---
 drivers/infiniband/hw/bnxtre/bnxt_qplib_fp.c    | 100 ++++++++++++++++++
 drivers/infiniband/hw/bnxtre/bnxt_qplib_fp.h    |   8 ++
 drivers/infiniband/hw/bnxtre/bnxt_re_ib_verbs.c | 133 ++++++++++++++++++++++++
 drivers/infiniband/hw/bnxtre/bnxt_re_ib_verbs.h |   2 +
 drivers/infiniband/hw/bnxtre/bnxt_re_main.c     |   2 +
 5 files changed, 245 insertions(+)

diff --git a/drivers/infiniband/hw/bnxtre/bnxt_qplib_fp.c b/drivers/infiniband/hw/bnxtre/bnxt_qplib_fp.c
index 419efe2..67188ce 100644
--- a/drivers/infiniband/hw/bnxtre/bnxt_qplib_fp.c
+++ b/drivers/infiniband/hw/bnxtre/bnxt_qplib_fp.c
@@ -1107,6 +1107,37 @@ void *bnxt_qplib_get_qp1_sq_buf(struct bnxt_qplib_qp *qp,
 	return NULL;
 }
 
+u32 bnxt_qplib_get_rq_prod_index(struct bnxt_qplib_qp *qp)
+{
+	struct bnxt_qplib_q *rq = &qp->rq;
+
+	return HWQ_CMP(rq->hwq.prod, &rq->hwq);
+}
+
+dma_addr_t bnxt_qplib_get_qp_buf_from_index(struct bnxt_qplib_qp *qp, u32 index)
+{
+	return (qp->rq_hdr_buf_map + index * qp->rq_hdr_buf_size);
+}
+
+void *bnxt_qplib_get_qp1_rq_buf(struct bnxt_qplib_qp *qp,
+				struct bnxt_qplib_sge *sge)
+{
+	struct bnxt_qplib_q *rq = &qp->rq;
+	u32 sw_prod;
+
+	memset(sge, 0, sizeof(*sge));
+
+	if (qp->rq_hdr_buf) {
+		sw_prod = HWQ_CMP(rq->hwq.prod, &rq->hwq);
+		sge->addr = (dma_addr_t)(qp->rq_hdr_buf_map +
+					 sw_prod * qp->rq_hdr_buf_size);
+		sge->lkey = 0xFFFFFFFF;
+		sge->size = qp->rq_hdr_buf_size;
+		return qp->rq_hdr_buf + sw_prod * sge->size;
+	}
+	return NULL;
+}
+
 void bnxt_qplib_post_send_db(struct bnxt_qplib_qp *qp)
 {
 	struct bnxt_qplib_q *sq = &qp->sq;
@@ -1355,6 +1386,75 @@ int bnxt_qplib_post_send(struct bnxt_qplib_qp *qp,
 	return rc;
 }
 
+void bnxt_qplib_post_recv_db(struct bnxt_qplib_qp *qp)
+{
+	struct bnxt_qplib_q *rq = &qp->rq;
+	struct dbr_dbr db_msg = { 0 };
+	u32 sw_prod;
+
+	sw_prod = HWQ_CMP(rq->hwq.prod, &rq->hwq);
+	db_msg.index = cpu_to_le32((sw_prod << DBR_DBR_INDEX_SFT) &
+				   DBR_DBR_INDEX_MASK);
+	db_msg.type_xid =
+		cpu_to_le32(((qp->id << DBR_DBR_XID_SFT) & DBR_DBR_XID_MASK) |
+			    DBR_DBR_TYPE_RQ);
+
+	/* Flush the writes to HW Rx WQE before the ringing Rx DB */
+	wmb();
+	__iowrite64_copy(qp->dpi->dbr, &db_msg, sizeof(db_msg) / sizeof(u64));
+}
+
+int bnxt_qplib_post_recv(struct bnxt_qplib_qp *qp,
+			 struct bnxt_qplib_swqe *wqe)
+{
+	struct bnxt_qplib_q *rq = &qp->rq;
+	struct rq_wqe *rqe, **rqe_ptr;
+	struct sq_sge *hw_sge;
+	u32 sw_prod;
+	int i, rc = 0;
+
+	if (qp->state == CMDQ_MODIFY_QP_NEW_STATE_ERR) {
+		dev_err(&rq->hwq.pdev->dev,
+			"QPLIB: FP: QP (0x%x) is in the 0x%x state",
+			qp->id, qp->state);
+		rc = -EINVAL;
+		goto done;
+	}
+	if (HWQ_CMP((rq->hwq.prod + 1), &rq->hwq) ==
+	    HWQ_CMP(rq->hwq.cons, &rq->hwq)) {
+		dev_err(&rq->hwq.pdev->dev,
+			"QPLIB: FP: QP (0x%x) RQ is full!", qp->id);
+		rc = -EINVAL;
+		goto done;
+	}
+	sw_prod = HWQ_CMP(rq->hwq.prod, &rq->hwq);
+	rq->swq[sw_prod].wr_id = wqe->wr_id;
+
+	rqe_ptr = (struct rq_wqe **)rq->hwq.pbl_ptr;
+	rqe = &rqe_ptr[RQE_PG(sw_prod)][RQE_IDX(sw_prod)];
+
+	memset(rqe, 0, BNXT_QPLIB_MAX_RQE_ENTRY_SIZE);
+
+	/* Calculate wqe_size16 and data_len */
+	for (i = 0, hw_sge = (struct sq_sge *)rqe->data;
+	     i < wqe->num_sge; i++, hw_sge++) {
+		hw_sge->va_or_pa = cpu_to_le64(wqe->sg_list[i].addr);
+		hw_sge->l_key = cpu_to_le32(wqe->sg_list[i].lkey);
+		hw_sge->size = cpu_to_le32(wqe->sg_list[i].size);
+	}
+	rqe->wqe_type = wqe->type;
+	rqe->flags = wqe->flags;
+	rqe->wqe_size = wqe->num_sge +
+			((offsetof(typeof(*rqe), data) + 15) >> 4);
+
+	/* Supply the rqe->wr_id index to the wr_id_tbl for now */
+	rqe->wr_id[0] = cpu_to_le32(sw_prod);
+
+	rq->hwq.prod++;
+done:
+	return rc;
+}
+
 /* CQ */
 
 /* Spinlock must be held */
diff --git a/drivers/infiniband/hw/bnxtre/bnxt_qplib_fp.h b/drivers/infiniband/hw/bnxtre/bnxt_qplib_fp.h
index 7fe98db..d9f2611 100644
--- a/drivers/infiniband/hw/bnxtre/bnxt_qplib_fp.h
+++ b/drivers/infiniband/hw/bnxtre/bnxt_qplib_fp.h
@@ -395,9 +395,17 @@ int bnxt_qplib_query_qp(struct bnxt_qplib_res *res, struct bnxt_qplib_qp *qp);
 int bnxt_qplib_destroy_qp(struct bnxt_qplib_res *res, struct bnxt_qplib_qp *qp);
 void *bnxt_qplib_get_qp1_sq_buf(struct bnxt_qplib_qp *qp,
 				struct bnxt_qplib_sge *sge);
+void *bnxt_qplib_get_qp1_rq_buf(struct bnxt_qplib_qp *qp,
+				struct bnxt_qplib_sge *sge);
+u32 bnxt_qplib_get_rq_prod_index(struct bnxt_qplib_qp *qp);
+dma_addr_t bnxt_qplib_get_qp_buf_from_index(struct bnxt_qplib_qp *qp,
+					    u32 index);
 void bnxt_qplib_post_send_db(struct bnxt_qplib_qp *qp);
 int bnxt_qplib_post_send(struct bnxt_qplib_qp *qp,
 			 struct bnxt_qplib_swqe *wqe);
+void bnxt_qplib_post_recv_db(struct bnxt_qplib_qp *qp);
+int bnxt_qplib_post_recv(struct bnxt_qplib_qp *qp,
+			 struct bnxt_qplib_swqe *wqe);
 int bnxt_qplib_create_cq(struct bnxt_qplib_res *res, struct bnxt_qplib_cq *cq);
 int bnxt_qplib_destroy_cq(struct bnxt_qplib_res *res, struct bnxt_qplib_cq *cq);
 
diff --git a/drivers/infiniband/hw/bnxtre/bnxt_re_ib_verbs.c b/drivers/infiniband/hw/bnxtre/bnxt_re_ib_verbs.c
index 540f2f2..5d6c89c 100644
--- a/drivers/infiniband/hw/bnxtre/bnxt_re_ib_verbs.c
+++ b/drivers/infiniband/hw/bnxtre/bnxt_re_ib_verbs.c
@@ -1644,6 +1644,61 @@ static int bnxt_re_build_qp1_send_v2(struct bnxt_re_qp *qp,
 	return rc;
 }
 
+/* For the MAD layer, it only provides the recv SGE the size of
+ * ib_grh + MAD datagram.  No Ethernet headers, Ethertype, BTH, DETH,
+ * nor RoCE iCRC.  The Cu+ solution must provide buffer for the entire
+ * receive packet (334 bytes) with no VLAN and then copy the GRH
+ * and the MAD datagram out to the provided SGE.
+ */
+static int bnxt_re_build_qp1_shadow_qp_recv(struct bnxt_re_qp *qp,
+					    struct ib_recv_wr *wr,
+					    struct bnxt_qplib_swqe *wqe,
+					    int payload_size)
+{
+	struct bnxt_qplib_sge ref, sge;
+	int rc = 0;
+	u32 rq_prod_index;
+	struct bnxt_re_sqp_entries *sqp_entry;
+
+	rq_prod_index = bnxt_qplib_get_rq_prod_index(&qp->qplib_qp);
+
+	if (bnxt_qplib_get_qp1_rq_buf(&qp->qplib_qp, &sge)) {
+		/* Create 1 SGE to receive the entire
+		 * ethernet packet
+		 */
+		/* Save the reference from ULP */
+		ref.addr = wqe->sg_list[0].addr;
+		ref.lkey = wqe->sg_list[0].lkey;
+		ref.size = wqe->sg_list[0].size;
+
+		sqp_entry = &qp->rdev->sqp_tbl[rq_prod_index];
+
+		/* SGE 1 */
+		wqe->sg_list[0].addr = sge.addr;
+		wqe->sg_list[0].lkey = sge.lkey;
+		wqe->sg_list[0].size = BNXT_QPLIB_MAX_QP1_RQ_HDR_SIZE_V2;
+		sge.size -= wqe->sg_list[0].size;
+		if (sge.size < 0) {
+			dev_err(rdev_to_dev(qp->rdev),
+				"QP1 rq buffer is empty!");
+			rc = -ENOMEM;
+			goto done;
+		}
+
+		sqp_entry->sge.addr = ref.addr;
+		sqp_entry->sge.lkey = ref.lkey;
+		sqp_entry->sge.size = ref.size;
+		/* Store the wrid for reporting completion */
+		sqp_entry->wrid = wqe->wr_id;
+		/* change the wqe->wrid to table index */
+		wqe->wr_id = rq_prod_index;
+	}
+	return 0;
+done:
+
+	return rc;
+}
+
 static int is_ud_qp(struct bnxt_re_qp *qp)
 {
 	return qp->qplib_qp.type == CMDQ_CREATE_QP_TYPE_UD;
@@ -1988,6 +2043,84 @@ int bnxt_re_post_send(struct ib_qp *ib_qp, struct ib_send_wr *wr,
 	return rc;
 }
 
+int bnxt_re_post_recv_shadow_qp(struct bnxt_re_dev *rdev,
+				struct bnxt_re_qp *qp,
+				struct ib_recv_wr *wr)
+{
+	struct bnxt_qplib_swqe wqe;
+	int rc = 0, payload_sz = 0;
+
+	memset(&wqe, 0, sizeof(wqe));
+	while (wr) {
+		/* House keeping */
+		memset(&wqe, 0, sizeof(wqe));
+
+		/* Common */
+		wqe.num_sge = wr->num_sge;
+		if (wr->num_sge > qp->qplib_qp.rq.max_sge) {
+			dev_err(rdev_to_dev(rdev),
+				"Limit exceeded for Receive SGEs");
+			rc = -EINVAL;
+			goto bad;
+		}
+		payload_sz = bnxt_re_build_sgl(wr->sg_list, wqe.sg_list,
+					       wr->num_sge);
+		wqe.wr_id = wr->wr_id;
+		wqe.type = BNXT_QPLIB_SWQE_TYPE_RECV;
+
+		if (!rc)
+			rc = bnxt_qplib_post_recv(&qp->qplib_qp, &wqe);
+bad:
+		if (rc)
+			break;
+
+		wr = wr->next;
+	}
+	bnxt_qplib_post_recv_db(&qp->qplib_qp);
+	return rc;
+}
+
+int bnxt_re_post_recv(struct ib_qp *ib_qp, struct ib_recv_wr *wr,
+		      struct ib_recv_wr **bad_wr)
+{
+	struct bnxt_re_qp *qp = to_bnxt_re(ib_qp, struct bnxt_re_qp, ib_qp);
+	struct bnxt_qplib_swqe wqe;
+	int rc = 0, payload_sz = 0;
+
+	while (wr) {
+		/* House keeping */
+		memset(&wqe, 0, sizeof(wqe));
+
+		/* Common */
+		wqe.num_sge = wr->num_sge;
+		if (wr->num_sge > qp->qplib_qp.rq.max_sge) {
+			dev_err(rdev_to_dev(qp->rdev),
+				"Limit exceeded for Receive SGEs");
+			rc = -EINVAL;
+			goto bad;
+		}
+
+		payload_sz = bnxt_re_build_sgl(wr->sg_list, wqe.sg_list,
+					       wr->num_sge);
+		wqe.wr_id = wr->wr_id;
+		wqe.type = BNXT_QPLIB_SWQE_TYPE_RECV;
+
+		if (ib_qp->qp_type == IB_QPT_GSI)
+			rc = bnxt_re_build_qp1_shadow_qp_recv(qp, wr, &wqe,
+							      payload_sz);
+		if (!rc)
+			rc = bnxt_qplib_post_recv(&qp->qplib_qp, &wqe);
+bad:
+		if (rc) {
+			*bad_wr = wr;
+			break;
+		}
+		wr = wr->next;
+	}
+	bnxt_qplib_post_recv_db(&qp->qplib_qp);
+	return rc;
+}
+
 /* Completion Queues */
 int bnxt_re_destroy_cq(struct ib_cq *ib_cq)
 {
diff --git a/drivers/infiniband/hw/bnxtre/bnxt_re_ib_verbs.h b/drivers/infiniband/hw/bnxtre/bnxt_re_ib_verbs.h
index becdcdc..9f3dd49 100644
--- a/drivers/infiniband/hw/bnxtre/bnxt_re_ib_verbs.h
+++ b/drivers/infiniband/hw/bnxtre/bnxt_re_ib_verbs.h
@@ -164,6 +164,8 @@ int bnxt_re_query_qp(struct ib_qp *qp, struct ib_qp_attr *qp_attr,
 int bnxt_re_destroy_qp(struct ib_qp *qp);
 int bnxt_re_post_send(struct ib_qp *qp, struct ib_send_wr *send_wr,
 		      struct ib_send_wr **bad_send_wr);
+int bnxt_re_post_recv(struct ib_qp *qp, struct ib_recv_wr *recv_wr,
+		      struct ib_recv_wr **bad_recv_wr);
 struct ib_cq *bnxt_re_create_cq(struct ib_device *ibdev,
 				const struct ib_cq_init_attr *attr,
 				struct ib_ucontext *context,
diff --git a/drivers/infiniband/hw/bnxtre/bnxt_re_main.c b/drivers/infiniband/hw/bnxtre/bnxt_re_main.c
index 14d1147..73dfadd 100644
--- a/drivers/infiniband/hw/bnxtre/bnxt_re_main.c
+++ b/drivers/infiniband/hw/bnxtre/bnxt_re_main.c
@@ -452,6 +452,8 @@ static int bnxt_re_register_ib(struct bnxt_re_dev *rdev)
 	ibdev->destroy_qp		= bnxt_re_destroy_qp;
 
 	ibdev->post_send		= bnxt_re_post_send;
+	ibdev->post_recv		= bnxt_re_post_recv;
+
 	ibdev->create_cq		= bnxt_re_create_cq;
 	ibdev->destroy_cq		= bnxt_re_destroy_cq;
 	ibdev->req_notify_cq		= bnxt_re_req_notify_cq;
-- 
2.5.5

  parent reply	other threads:[~2016-12-09  6:48 UTC|newest]

Thread overview: 46+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-12-09  6:47 [PATCH V2 00/22] Broadcom RoCE Driver (bnxt_re) Selvin Xavier
2016-12-09  6:47 ` [PATCH V2 01/22] bnxt_re: Add bnxt_re RoCE driver files Selvin Xavier
2016-12-09  6:47 ` [PATCH V2 02/22] bnxt_re: Introducing autogenerated Host Software Interface(hsi) file Selvin Xavier
2016-12-09  6:47 ` [PATCH V2 03/22] bnxt_re: register with the NIC driver Selvin Xavier
2016-12-10  0:03   ` Jonathan Toppins
2016-12-09  6:47 ` [PATCH V2 04/22] bnxt_re: Enabling RoCE control path Selvin Xavier
2016-12-09  6:47 ` [PATCH V2 05/22] bnxt_re: Adding Notification Queue support Selvin Xavier
2016-12-09  6:48 ` [PATCH V2 06/22] bnxt_re: Support for PD, ucontext and mmap verbs Selvin Xavier
     [not found] ` <1481266096-23331-1-git-send-email-selvin.xavier-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>
2016-12-09  6:48   ` [PATCH V2 07/22] bnxt_re: Support for query and modify device verbs Selvin Xavier
2016-12-09  6:48   ` [PATCH V2 10/22] bnxt_re: Support for CQ verbs Selvin Xavier
     [not found]     ` <1481266096-23331-11-git-send-email-selvin.xavier-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>
2016-12-12 21:03       ` Jonathan Toppins
2016-12-09  6:48   ` [PATCH V2 22/22] bnxt_re: Add bnxt_re driver build support Selvin Xavier
2016-12-09 11:21     ` kbuild test robot
2016-12-10  5:36   ` [PATCH V2 00/22] Broadcom RoCE Driver (bnxt_re) Selvin Xavier
     [not found]     ` <CA+sbYW1ZEa5fndGkvN8OXr-orcUx4jaL73Di8zBJQX_uCdK=Ww-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2016-12-12 17:07       ` Jason Gunthorpe
     [not found]         ` <20161212170701.GA28387-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>
2016-12-13  6:04           ` Selvin Xavier
2016-12-12 16:54   ` Jonathan Toppins
     [not found]     ` <9cf03e2b-a16d-19ec-a8ce-14f24272bf6a-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2016-12-13  4:52       ` Selvin Xavier
2016-12-13  6:41         ` Michael Chan
2016-12-12 23:52   ` Doug Ledford
2016-12-13  3:54     ` Selvin Xavier
     [not found]     ` <23e26353-4317-2836-9f94-d1fc3274a770-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2016-12-13  7:59       ` Or Gerlitz
     [not found]         ` <CAJ3xEMh98kC1KXGf7uHKD-H91f_NiZXaz-3yTtwQ2s-D7rYqMQ-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2016-12-13  8:36           ` Selvin Xavier
2016-12-09  6:48 ` [PATCH V2 08/22] bnxt_re: Adding support for port related verbs Selvin Xavier
2016-12-09  6:48 ` [PATCH V2 09/22] bnxt_re: Support for GID " Selvin Xavier
2016-12-09  6:48 ` [PATCH V2 11/22] bnxt_re: Support for AH verbs Selvin Xavier
2016-12-09  6:48 ` [PATCH V2 12/22] bnxt_re: Support memory registration verbs Selvin Xavier
2016-12-09  6:48 ` [PATCH V2 13/22] bnxt_re: Support QP verbs Selvin Xavier
     [not found]   ` <1481266096-23331-14-git-send-email-selvin.xavier-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>
2016-12-12 18:27     ` Leon Romanovsky
     [not found]       ` <20161212182737.GC8204-U/DQcQFIOTAAJjI8aNfphQ@public.gmane.org>
2016-12-13  6:08         ` Selvin Xavier
2016-12-09  6:48 ` [PATCH V2 14/22] bnxt_re: Support post_send verb Selvin Xavier
2016-12-09  6:48 ` Selvin Xavier [this message]
2016-12-09  6:48 ` [PATCH V2 16/22] bnxt_re: Support poll_cq verb Selvin Xavier
2016-12-09  6:48 ` [PATCH V2 17/22] bnxt_re: Handling dispatching of events to IB stack Selvin Xavier
2016-12-09  6:48 ` [PATCH V2 18/22] bnxt_re: Support for DCB Selvin Xavier
2016-12-10 13:50   ` Or Gerlitz
2016-12-13  6:25     ` Selvin Xavier
     [not found]       ` <CA+sbYW1irBd0cTqJJSGJWRbBi-iFzvX3JpoTfF_daU47EqNtAg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2016-12-13 16:56         ` Jason Gunthorpe
2016-12-09  6:48 ` [PATCH V2 19/22] bnxt_re: Support debugfs Selvin Xavier
2016-12-09  6:48 ` [PATCH V2 20/22] bnxt_re: Set uverbs command mask Selvin Xavier
2016-12-09  6:48 ` [PATCH V2 21/22] bnxt_re: Add QP event handling Selvin Xavier
     [not found]   ` <1481266096-23331-22-git-send-email-selvin.xavier-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>
2016-12-09 12:12     ` Sergei Shtylyov
2016-12-09 15:26 ` [PATCH V2 00/22] Broadcom RoCE Driver (bnxt_re) David Miller
2016-12-09 17:52   ` Selvin Xavier
2016-12-09 16:27 ` Leon Romanovsky
2016-12-13  6:54 ` Or Gerlitz

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