rdma/cxgb4: Add support for srq functions & structs

This patch adds kernel mode t4_srq structures and support functions,
uapi structures and defines, as well as firmware work request structures.
Signed-off-by: Raju Rangoju <rajur@chelsio.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/cxgb4/iw_cxgb4.h

@@ -97,6 +97,7 @@ struct c4iw_resource {
 	struct c4iw_id_table tpt_table;
 	struct c4iw_id_table qid_table;
 	struct c4iw_id_table pdid_table;
+	struct c4iw_id_table srq_table;
 };
 
 struct c4iw_qid_list {
@@ -130,6 +131,8 @@ struct c4iw_stats {
 	struct c4iw_stat stag;
 	struct c4iw_stat pbl;
 	struct c4iw_stat rqt;
+	struct c4iw_stat srqt;
+	struct c4iw_stat srq;
 	struct c4iw_stat ocqp;
 	u64  db_full;
 	u64  db_empty;
@@ -549,6 +552,7 @@ struct c4iw_qp {
 	struct kref kref;
 	wait_queue_head_t wait;
 	int sq_sig_all;
+	struct c4iw_srq *srq;
 	struct work_struct free_work;
 	struct c4iw_ucontext *ucontext;
 	struct c4iw_wr_wait *wr_waitp;
@@ -559,6 +563,26 @@ static inline struct c4iw_qp *to_c4iw_qp(struct ib_qp *ibqp)
 	return container_of(ibqp, struct c4iw_qp, ibqp);
 }
 
+struct c4iw_srq {
+	struct ib_srq ibsrq;
+	struct list_head db_fc_entry;
+	struct c4iw_dev *rhp;
+	struct t4_srq wq;
+	struct sk_buff *destroy_skb;
+	u32 srq_limit;
+	u32 pdid;
+	int idx;
+	u32 flags;
+	spinlock_t lock; /* protects srq */
+	struct c4iw_wr_wait *wr_waitp;
+	bool armed;
+};
+
+static inline struct c4iw_srq *to_c4iw_srq(struct ib_srq *ibsrq)
+{
+	return container_of(ibsrq, struct c4iw_srq, ibsrq);
+}
+
 struct c4iw_ucontext {
 	struct ib_ucontext ibucontext;
 	struct c4iw_dev_ucontext uctx;
@@ -1040,6 +1064,13 @@ struct ib_cq *c4iw_create_cq(struct ib_device *ibdev,
 			     struct ib_udata *udata);
 int c4iw_resize_cq(struct ib_cq *cq, int cqe, struct ib_udata *udata);
 int c4iw_arm_cq(struct ib_cq *ibcq, enum ib_cq_notify_flags flags);
+int c4iw_modify_srq(struct ib_srq *ib_srq, struct ib_srq_attr *attr,
+		    enum ib_srq_attr_mask srq_attr_mask,
+		    struct ib_udata *udata);
+int c4iw_destroy_srq(struct ib_srq *ib_srq);
+struct ib_srq *c4iw_create_srq(struct ib_pd *pd,
+			       struct ib_srq_init_attr *attrs,
+			       struct ib_udata *udata);
 int c4iw_destroy_qp(struct ib_qp *ib_qp);
 struct ib_qp *c4iw_create_qp(struct ib_pd *pd,
 			     struct ib_qp_init_attr *attrs,
@@ -1076,12 +1107,19 @@ extern c4iw_handler_func c4iw_handlers[NUM_CPL_CMDS];
 void __iomem *c4iw_bar2_addrs(struct c4iw_rdev *rdev, unsigned int qid,
 			      enum cxgb4_bar2_qtype qtype,
 			      unsigned int *pbar2_qid, u64 *pbar2_pa);
+int c4iw_alloc_srq_idx(struct c4iw_rdev *rdev);
+void c4iw_free_srq_idx(struct c4iw_rdev *rdev, int idx);
 extern void c4iw_log_wr_stats(struct t4_wq *wq, struct t4_cqe *cqe);
 extern int c4iw_wr_log;
 extern int db_fc_threshold;
 extern int db_coalescing_threshold;
 extern int use_dsgl;
 void c4iw_invalidate_mr(struct c4iw_dev *rhp, u32 rkey);
+void c4iw_dispatch_srq_limit_reached_event(struct c4iw_srq *srq);
+void c4iw_copy_wr_to_srq(struct t4_srq *srq, union t4_recv_wr *wqe, u8 len16);
+void c4iw_flush_srqidx(struct c4iw_qp *qhp, u32 srqidx);
+int c4iw_post_srq_recv(struct ib_srq *ibsrq, struct ib_recv_wr *wr,
+		       struct ib_recv_wr **bad_wr);
 struct c4iw_wr_wait *c4iw_alloc_wr_wait(gfp_t gfp);
 
 typedef int c4iw_restrack_func(struct sk_buff *msg,

drivers/infiniband/hw/cxgb4/t4.h

@@ -52,12 +52,16 @@ struct t4_status_page {
 	__be16 pidx;
 	u8 qp_err;	/* flit 1 - sw owns */
 	u8 db_off;
-	u8 pad;
+	u8 pad[2];
 	u16 host_wq_pidx;
 	u16 host_cidx;
 	u16 host_pidx;
+	u16 pad2;
+	u32 srqidx;
 };
 
+#define T4_RQT_ENTRY_SHIFT 6
+#define T4_RQT_ENTRY_SIZE  BIT(T4_RQT_ENTRY_SHIFT)
 #define T4_EQ_ENTRY_SIZE 64
 
 #define T4_SQ_NUM_SLOTS 5
@@ -248,6 +252,7 @@ struct t4_cqe {
 /* used for RQ completion processing */
 #define CQE_WRID_STAG(x)  (be32_to_cpu((x)->u.rcqe.stag))
 #define CQE_WRID_MSN(x)   (be32_to_cpu((x)->u.rcqe.msn))
+#define CQE_ABS_RQE_IDX(x) (be32_to_cpu((x)->u.srcqe.abs_rqe_idx))
 
 /* used for SQ completion processing */
 #define CQE_WRID_SQ_IDX(x)	((x)->u.scqe.cidx)
@@ -331,6 +336,7 @@ struct t4_swrqe {
 	u64 wr_id;
 	ktime_t	host_time;
 	u64 sge_ts;
+	int valid;
 };
 
 struct t4_rq {
@@ -360,8 +366,98 @@ struct t4_wq {
 	void __iomem *db;
 	struct c4iw_rdev *rdev;
 	int flushed;
+	u8 *qp_errp;
+	u32 *srqidxp;
+};
+
+struct t4_srq_pending_wr {
+	u64 wr_id;
+	union t4_recv_wr wqe;
+	u8 len16;
+};
+
+struct t4_srq {
+	union t4_recv_wr *queue;
+	dma_addr_t dma_addr;
+	DECLARE_PCI_UNMAP_ADDR(mapping);
+	struct t4_swrqe *sw_rq;
+	void __iomem *bar2_va;
+	u64 bar2_pa;
+	size_t memsize;
+	u32 bar2_qid;
+	u32 qid;
+	u32 msn;
+	u32 rqt_hwaddr;
+	u32 rqt_abs_idx;
+	u16 rqt_size;
+	u16 size;
+	u16 cidx;
+	u16 pidx;
+	u16 wq_pidx;
+	u16 wq_pidx_inc;
+	u16 in_use;
+	struct t4_srq_pending_wr *pending_wrs;
+	u16 pending_cidx;
+	u16 pending_pidx;
+	u16 pending_in_use;
+	u16 ooo_count;
 };
 
+static inline u32 t4_srq_avail(struct t4_srq *srq)
+{
+	return srq->size - 1 - srq->in_use;
+}
+
+static inline void t4_srq_produce(struct t4_srq *srq, u8 len16)
+{
+	srq->in_use++;
+	if (++srq->pidx == srq->size)
+		srq->pidx = 0;
+	srq->wq_pidx += DIV_ROUND_UP(len16 * 16, T4_EQ_ENTRY_SIZE);
+	if (srq->wq_pidx >= srq->size * T4_RQ_NUM_SLOTS)
+		srq->wq_pidx %= srq->size * T4_RQ_NUM_SLOTS;
+	srq->queue[srq->size].status.host_pidx = srq->pidx;
+}
+
+static inline void t4_srq_produce_pending_wr(struct t4_srq *srq)
+{
+	srq->pending_in_use++;
+	srq->in_use++;
+	if (++srq->pending_pidx == srq->size)
+		srq->pending_pidx = 0;
+}
+
+static inline void t4_srq_consume_pending_wr(struct t4_srq *srq)
+{
+	srq->pending_in_use--;
+	srq->in_use--;
+	if (++srq->pending_cidx == srq->size)
+		srq->pending_cidx = 0;
+}
+
+static inline void t4_srq_produce_ooo(struct t4_srq *srq)
+{
+	srq->in_use--;
+	srq->ooo_count++;
+}
+
+static inline void t4_srq_consume_ooo(struct t4_srq *srq)
+{
+	srq->cidx++;
+	if (srq->cidx == srq->size)
+		srq->cidx  = 0;
+	srq->queue[srq->size].status.host_cidx = srq->cidx;
+	srq->ooo_count--;
+}
+
+static inline void t4_srq_consume(struct t4_srq *srq)
+{
+	srq->in_use--;
+	if (++srq->cidx == srq->size)
+		srq->cidx = 0;
+	srq->queue[srq->size].status.host_cidx = srq->cidx;
+}
+
 static inline int t4_rqes_posted(struct t4_wq *wq)
 {
 	return wq->rq.in_use;
@@ -475,6 +571,25 @@ static inline void pio_copy(u64 __iomem *dst, u64 *src)
 	}
 }
 
+static inline void t4_ring_srq_db(struct t4_srq *srq, u16 inc, u8 len16,
+				  union t4_recv_wr *wqe)
+{
+	/* Flush host queue memory writes. */
+	wmb();
+	if (inc == 1 && srq->bar2_qid == 0 && wqe) {
+		pr_debug("%s : WC srq->pidx = %d; len16=%d\n",
+			 __func__, srq->pidx, len16);
+		pio_copy(srq->bar2_va + SGE_UDB_WCDOORBELL, (u64 *)wqe);
+	} else {
+		pr_debug("%s: DB srq->pidx = %d; len16=%d\n",
+			 __func__, srq->pidx, len16);
+		writel(PIDX_T5_V(inc) | QID_V(srq->bar2_qid),
+		       srq->bar2_va + SGE_UDB_KDOORBELL);
+	}
+	/* Flush user doorbell area writes. */
+	wmb();
+}
+
 static inline void t4_ring_sq_db(struct t4_wq *wq, u16 inc, union t4_wr *wqe)
 {
 

drivers/infiniband/hw/cxgb4/t4fw_ri_api.h

@@ -263,6 +263,7 @@ enum fw_ri_res_type {
 	FW_RI_RES_TYPE_SQ,
 	FW_RI_RES_TYPE_RQ,
 	FW_RI_RES_TYPE_CQ,
+	FW_RI_RES_TYPE_SRQ,
 };
 
 enum fw_ri_res_op {
@@ -296,6 +297,20 @@ struct fw_ri_res {
 			__be32 r6_lo;
 			__be64 r7;
 		} cq;
+		struct fw_ri_res_srq {
+			__u8   restype;
+			__u8   op;
+			__be16 r3;
+			__be32 eqid;
+			__be32 r4[2];
+			__be32 fetchszm_to_iqid;
+			__be32 dcaen_to_eqsize;
+			__be64 eqaddr;
+			__be32 srqid;
+			__be32 pdid;
+			__be32 hwsrqsize;
+			__be32 hwsrqaddr;
+		} srq;
 	} u;
 };
 
@@ -707,6 +722,10 @@ enum fw_ri_init_p2ptype {
 	FW_RI_INIT_P2PTYPE_DISABLED		= 0xf,
 };
 
+enum fw_ri_init_rqeqid_srq {
+	FW_RI_INIT_RQEQID_SRQ			= 1 << 31,
+};
+
 struct fw_ri_wr {
 	__be32 op_compl;
 	__be32 flowid_len16;

include/uapi/rdma/cxgb4-abi.h

@@ -84,6 +84,23 @@ struct c4iw_create_qp_resp {
 	__u32 flags;
 };
 
+struct c4iw_create_srq_resp {
+	__aligned_u64 srq_key;
+	__aligned_u64 srq_db_gts_key;
+	__aligned_u64 srq_memsize;
+	__u32 srqid;
+	__u32 srq_size;
+	__u32 rqt_abs_idx;
+	__u32 qid_mask;
+	__u32 flags;
+	__u32 reserved; /* explicit padding */
+};
+
+enum {
+	/* HW supports SRQ_LIMIT_REACHED event */
+	T4_SRQ_LIMIT_SUPPORT = 1 << 0,
+};
+
 struct c4iw_alloc_ucontext_resp {
 	__aligned_u64 status_page_key;
 	__u32 status_page_size;