IB/hfi1, qib, rdmavt: Move AETH credit functions into rdmavt

Add rvt_compute_aeth() and rvt_get_credit() as shared functions in
rdmavt, moved from hfi1/qib logic.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Brian Welty <brian.welty@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

4 files changed, 20 insertions, 162 deletions

diff --git a/drivers/infiniband/hw/qib/qib_common.h b/drivers/infiniband/hw/qib/qib_common.h
index 1d6e63eb1146..a4a1f56ce824 100644
--- a/drivers/infiniband/hw/qib/qib_common.h
+++ b/drivers/infiniband/hw/qib/qib_common.h
@@ -742,11 +742,7 @@ struct qib_tid_session_member {
 #define SIZE_OF_CRC 1
 
 #define QIB_DEFAULT_P_KEY 0xFFFF
-#define QIB_AETH_CREDIT_SHIFT 24
-#define QIB_AETH_CREDIT_MASK 0x1F
-#define QIB_AETH_CREDIT_INVAL 0x1F
 #define QIB_PSN_MASK 0xFFFFFF
-#define QIB_MSN_MASK 0xFFFFFF
 #define QIB_EAGER_TID_ID QLOGIC_IB_I_TID_MASK
 #define QIB_MULTICAST_QPN 0xFFFFFF
 
diff --git a/drivers/infiniband/hw/qib/qib_qp.c b/drivers/infiniband/hw/qib/qib_qp.c
index 99d31efe4c2f..e869be01ae86 100644
--- a/drivers/infiniband/hw/qib/qib_qp.c
+++ b/drivers/infiniband/hw/qib/qib_qp.c
@@ -61,43 +61,6 @@ static inline unsigned find_next_offset(struct rvt_qpn_table *qpt,
 	return off;
 }
 
-/*
- * Convert the AETH credit code into the number of credits.
- */
-static u32 credit_table[31] = {
-	0,                      /* 0 */
-	1,                      /* 1 */
-	2,                      /* 2 */
-	3,                      /* 3 */
-	4,                      /* 4 */
-	6,                      /* 5 */
-	8,                      /* 6 */
-	12,                     /* 7 */
-	16,                     /* 8 */
-	24,                     /* 9 */
-	32,                     /* A */
-	48,                     /* B */
-	64,                     /* C */
-	96,                     /* D */
-	128,                    /* E */
-	192,                    /* F */
-	256,                    /* 10 */
-	384,                    /* 11 */
-	512,                    /* 12 */
-	768,                    /* 13 */
-	1024,                   /* 14 */
-	1536,                   /* 15 */
-	2048,                   /* 16 */
-	3072,                   /* 17 */
-	4096,                   /* 18 */
-	6144,                   /* 19 */
-	8192,                   /* 1A */
-	12288,                  /* 1B */
-	16384,                  /* 1C */
-	24576,                  /* 1D */
-	32768                   /* 1E */
-};
-
 const struct rvt_operation_params qib_post_parms[RVT_OPERATION_MAX] = {
 [IB_WR_RDMA_WRITE] = {
 	.length = sizeof(struct ib_rdma_wr),
@@ -354,66 +317,6 @@ u32 qib_mtu_from_qp(struct rvt_dev_info *rdi, struct rvt_qp *qp, u32 pmtu)
 	return ib_mtu_enum_to_int(pmtu);
 }
 
-/**
- * qib_compute_aeth - compute the AETH (syndrome + MSN)
- * @qp: the queue pair to compute the AETH for
- *
- * Returns the AETH.
- */
-__be32 qib_compute_aeth(struct rvt_qp *qp)
-{
-	u32 aeth = qp->r_msn & QIB_MSN_MASK;
-
-	if (qp->ibqp.srq) {
-		/*
-		 * Shared receive queues don't generate credits.
-		 * Set the credit field to the invalid value.
-		 */
-		aeth |= QIB_AETH_CREDIT_INVAL << QIB_AETH_CREDIT_SHIFT;
-	} else {
-		u32 min, max, x;
-		u32 credits;
-		struct rvt_rwq *wq = qp->r_rq.wq;
-		u32 head;
-		u32 tail;
-
-		/* sanity check pointers before trusting them */
-		head = wq->head;
-		if (head >= qp->r_rq.size)
-			head = 0;
-		tail = wq->tail;
-		if (tail >= qp->r_rq.size)
-			tail = 0;
-		/*
-		 * Compute the number of credits available (RWQEs).
-		 * XXX Not holding the r_rq.lock here so there is a small
-		 * chance that the pair of reads are not atomic.
-		 */
-		credits = head - tail;
-		if ((int)credits < 0)
-			credits += qp->r_rq.size;
-		/*
-		 * Binary search the credit table to find the code to
-		 * use.
-		 */
-		min = 0;
-		max = 31;
-		for (;;) {
-			x = (min + max) / 2;
-			if (credit_table[x] == credits)
-				break;
-			if (credit_table[x] > credits)
-				max = x;
-			else if (min == x)
-				break;
-			else
-				min = x;
-		}
-		aeth |= x << QIB_AETH_CREDIT_SHIFT;
-	}
-	return cpu_to_be32(aeth);
-}
-
 void *qib_qp_priv_alloc(struct rvt_dev_info *rdi, struct rvt_qp *qp, gfp_t gfp)
 {
 	struct qib_qp_priv *priv;
@@ -474,43 +377,6 @@ void qib_flush_qp_waiters(struct rvt_qp *qp)
 }
 
 /**
- * qib_get_credit - flush the send work queue of a QP
- * @qp: the qp who's send work queue to flush
- * @aeth: the Acknowledge Extended Transport Header
- *
- * The QP s_lock should be held.
- */
-void qib_get_credit(struct rvt_qp *qp, u32 aeth)
-{
-	u32 credit = (aeth >> QIB_AETH_CREDIT_SHIFT) & QIB_AETH_CREDIT_MASK;
-
-	/*
-	 * If the credit is invalid, we can send
-	 * as many packets as we like.  Otherwise, we have to
-	 * honor the credit field.
-	 */
-	if (credit == QIB_AETH_CREDIT_INVAL) {
-		if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT)) {
-			qp->s_flags |= RVT_S_UNLIMITED_CREDIT;
-			if (qp->s_flags & RVT_S_WAIT_SSN_CREDIT) {
-				qp->s_flags &= ~RVT_S_WAIT_SSN_CREDIT;
-				qib_schedule_send(qp);
-			}
-		}
-	} else if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT)) {
-		/* Compute new LSN (i.e., MSN + credit) */
-		credit = (aeth + credit_table[credit]) & QIB_MSN_MASK;
-		if (qib_cmp24(credit, qp->s_lsn) > 0) {
-			qp->s_lsn = credit;
-			if (qp->s_flags & RVT_S_WAIT_SSN_CREDIT) {
-				qp->s_flags &= ~RVT_S_WAIT_SSN_CREDIT;
-				qib_schedule_send(qp);
-			}
-		}
-	}
-}
-
-/**
  * qib_check_send_wqe - validate wr/wqe
  * @qp - The qp
  * @wqe - The built wqe
diff --git a/drivers/infiniband/hw/qib/qib_rc.c b/drivers/infiniband/hw/qib/qib_rc.c
index 5b0d01be7e50..6a189310e12d 100644
--- a/drivers/infiniband/hw/qib/qib_rc.c
+++ b/drivers/infiniband/hw/qib/qib_rc.c
@@ -144,7 +144,7 @@ static int qib_make_rc_ack(struct qib_ibdev *dev, struct rvt_qp *qp,
 				qp->s_ack_state = OP(RDMA_READ_RESPONSE_ONLY);
 				e->sent = 1;
 			}
-			ohdr->u.aeth = qib_compute_aeth(qp);
+			ohdr->u.aeth = rvt_compute_aeth(qp);
 			hwords++;
 			qp->s_ack_rdma_psn = e->psn;
 			bth2 = qp->s_ack_rdma_psn++ & QIB_PSN_MASK;
@@ -153,7 +153,7 @@ static int qib_make_rc_ack(struct qib_ibdev *dev, struct rvt_qp *qp,
 			qp->s_cur_sge = NULL;
 			len = 0;
 			qp->s_ack_state = OP(ATOMIC_ACKNOWLEDGE);
-			ohdr->u.at.aeth = qib_compute_aeth(qp);
+			ohdr->u.at.aeth = rvt_compute_aeth(qp);
 			ib_u64_put(e->atomic_data, &ohdr->u.at.atomic_ack_eth);
 			hwords += sizeof(ohdr->u.at) / sizeof(u32);
 			bth2 = e->psn & QIB_PSN_MASK;
@@ -174,7 +174,7 @@ static int qib_make_rc_ack(struct qib_ibdev *dev, struct rvt_qp *qp,
 		if (len > pmtu)
 			len = pmtu;
 		else {
-			ohdr->u.aeth = qib_compute_aeth(qp);
+			ohdr->u.aeth = rvt_compute_aeth(qp);
 			hwords++;
 			qp->s_ack_state = OP(RDMA_READ_RESPONSE_LAST);
 			e = &qp->s_ack_queue[qp->s_tail_ack_queue];
@@ -197,11 +197,11 @@ normal:
 		qp->s_cur_sge = NULL;
 		if (qp->s_nak_state)
 			ohdr->u.aeth =
-				cpu_to_be32((qp->r_msn & QIB_MSN_MASK) |
+				cpu_to_be32((qp->r_msn & RVT_MSN_MASK) |
 					    (qp->s_nak_state <<
-					     QIB_AETH_CREDIT_SHIFT));
+					     RVT_AETH_CREDIT_SHIFT));
 		else
-			ohdr->u.aeth = qib_compute_aeth(qp);
+			ohdr->u.aeth = rvt_compute_aeth(qp);
 		hwords++;
 		len = 0;
 		bth0 = OP(ACKNOWLEDGE) << 24;
@@ -331,7 +331,7 @@ int qib_make_rc_req(struct rvt_qp *qp, unsigned long *flags)
 		case IB_WR_SEND_WITH_IMM:
 			/* If no credit, return. */
 			if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT) &&
-			    qib_cmp24(wqe->ssn, qp->s_lsn + 1) > 0) {
+			    rvt_cmp_msn(wqe->ssn, qp->s_lsn + 1) > 0) {
 				qp->s_flags |= RVT_S_WAIT_SSN_CREDIT;
 				goto bail;
 			}
@@ -362,7 +362,7 @@ int qib_make_rc_req(struct rvt_qp *qp, unsigned long *flags)
 		case IB_WR_RDMA_WRITE_WITH_IMM:
 			/* If no credit, return. */
 			if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT) &&
-			    qib_cmp24(wqe->ssn, qp->s_lsn + 1) > 0) {
+			    rvt_cmp_msn(wqe->ssn, qp->s_lsn + 1) > 0) {
 				qp->s_flags |= RVT_S_WAIT_SSN_CREDIT;
 				goto bail;
 			}
@@ -658,11 +658,11 @@ void qib_send_rc_ack(struct rvt_qp *qp)
 	if (qp->s_mig_state == IB_MIG_MIGRATED)
 		bth0 |= IB_BTH_MIG_REQ;
 	if (qp->r_nak_state)
-		ohdr->u.aeth = cpu_to_be32((qp->r_msn & QIB_MSN_MASK) |
+		ohdr->u.aeth = cpu_to_be32((qp->r_msn & RVT_MSN_MASK) |
 					    (qp->r_nak_state <<
-					     QIB_AETH_CREDIT_SHIFT));
+					     RVT_AETH_CREDIT_SHIFT));
 	else
-		ohdr->u.aeth = qib_compute_aeth(qp);
+		ohdr->u.aeth = rvt_compute_aeth(qp);
 	lrh0 |= ibp->sl_to_vl[qp->remote_ah_attr.sl] << 12 |
 		qp->remote_ah_attr.sl << 4;
 	hdr.lrh[0] = cpu_to_be16(lrh0);
@@ -1098,7 +1098,7 @@ static int do_rc_ack(struct rvt_qp *qp, u32 aeth, u32 psn, int opcode,
 	 * request but will include an ACK'ed request(s).
 	 */
 	ack_psn = psn;
-	if (aeth >> 29)
+	if (aeth >> RVT_AETH_NAK_SHIFT)
 		ack_psn--;
 	wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
 	ibp = to_iport(qp->ibqp.device, qp->port_num);
@@ -1178,7 +1178,7 @@ static int do_rc_ack(struct rvt_qp *qp, u32 aeth, u32 psn, int opcode,
 			break;
 	}
 
-	switch (aeth >> 29) {
+	switch (aeth >> RVT_AETH_NAK_SHIFT) {
 	case 0:         /* ACK */
 		this_cpu_inc(*ibp->rvp.rc_acks);
 		if (qp->s_acked != qp->s_tail) {
@@ -1201,7 +1201,7 @@ static int do_rc_ack(struct rvt_qp *qp, u32 aeth, u32 psn, int opcode,
 			qp->s_flags &= ~RVT_S_WAIT_ACK;
 			qib_schedule_send(qp);
 		}
-		qib_get_credit(qp, aeth);
+		rvt_get_credit(qp, aeth);
 		qp->s_rnr_retry = qp->s_rnr_retry_cnt;
 		qp->s_retry = qp->s_retry_cnt;
 		update_last_psn(qp, psn);
@@ -1232,8 +1232,8 @@ static int do_rc_ack(struct rvt_qp *qp, u32 aeth, u32 psn, int opcode,
 		qp->s_flags |= RVT_S_WAIT_RNR;
 		qp->s_timer.function = qib_rc_rnr_retry;
 		qp->s_timer.expires = jiffies + usecs_to_jiffies(
-			ib_qib_rnr_table[(aeth >> QIB_AETH_CREDIT_SHIFT) &
-					   QIB_AETH_CREDIT_MASK]);
+			ib_qib_rnr_table[(aeth >> RVT_AETH_CREDIT_SHIFT) &
+					   RVT_AETH_CREDIT_MASK]);
 		add_timer(&qp->s_timer);
 		goto bail;
 
@@ -1242,8 +1242,8 @@ static int do_rc_ack(struct rvt_qp *qp, u32 aeth, u32 psn, int opcode,
 			goto bail;
 		/* The last valid PSN is the previous PSN. */
 		update_last_psn(qp, psn - 1);
-		switch ((aeth >> QIB_AETH_CREDIT_SHIFT) &
-			QIB_AETH_CREDIT_MASK) {
+		switch ((aeth >> RVT_AETH_CREDIT_SHIFT) &
+			RVT_AETH_CREDIT_MASK) {
 		case 0: /* PSN sequence error */
 			ibp->rvp.n_seq_naks++;
 			/*
@@ -1400,8 +1400,8 @@ static void qib_rc_rcv_resp(struct qib_ibport *ibp,
 		/* Update credits for "ghost" ACKs */
 		if (diff == 0 && opcode == OP(ACKNOWLEDGE)) {
 			aeth = be32_to_cpu(ohdr->u.aeth);
-			if ((aeth >> 29) == 0)
-				qib_get_credit(qp, aeth);
+			if ((aeth >> RVT_AETH_NAK_SHIFT) == 0)
+				rvt_get_credit(qp, aeth);
 		}
 		goto ack_done;
 	}
diff --git a/drivers/infiniband/hw/qib/qib_verbs.h b/drivers/infiniband/hw/qib/qib_verbs.h
index e399cb0fb4ee..226e81fe39d6 100644
--- a/drivers/infiniband/hw/qib/qib_verbs.h
+++ b/drivers/infiniband/hw/qib/qib_verbs.h
@@ -270,8 +270,6 @@ int qib_snapshot_counters(struct qib_pportdata *ppd, u64 *swords,
 int qib_get_counters(struct qib_pportdata *ppd,
 		     struct qib_verbs_counters *cntrs);
 
-__be32 qib_compute_aeth(struct rvt_qp *qp);
-
 /*
  * Functions provided by qib driver for rdmavt to use
  */
@@ -294,8 +292,6 @@ void qib_qp_iter_print(struct seq_file *s, struct qib_qp_iter *iter);
 
 #endif
 
-void qib_get_credit(struct rvt_qp *qp, u32 aeth);
-
 unsigned qib_pkt_delay(u32 plen, u8 snd_mult, u8 rcv_mult);
 
 void qib_verbs_sdma_desc_avail(struct qib_pportdata *ppd, unsigned avail);