cxgb4: Enable doorbell drop recovery only for T4 adapter

Signed-off-by: Santosh Rastapur <santosh@chelsio.com>
Signed-off-by: Vipul Pandya <vipul@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 71 insertions, 16 deletions

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
index ce1451cb5a26..177d0c199e01 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
@@ -3227,10 +3227,18 @@ EXPORT_SYMBOL(cxgb4_port_chan);
 unsigned int cxgb4_dbfifo_count(const struct net_device *dev, int lpfifo)
 {
         struct adapter *adap = netdev2adap(dev);
-        u32 v;
+        u32 v1, v2, lp_count, hp_count;
 
-        v = t4_read_reg(adap, A_SGE_DBFIFO_STATUS);
-        return lpfifo ? G_LP_COUNT(v) : G_HP_COUNT(v);
+        v1 = t4_read_reg(adap, A_SGE_DBFIFO_STATUS);
+        v2 = t4_read_reg(adap, SGE_DBFIFO_STATUS2);
+        if (is_t4(adap->chip)) {
+                lp_count = G_LP_COUNT(v1);
+                hp_count = G_HP_COUNT(v1);
+        } else {
+                lp_count = G_LP_COUNT_T5(v1);
+                hp_count = G_HP_COUNT_T5(v2);
+        }
+        return lpfifo ? lp_count : hp_count;
 }
 EXPORT_SYMBOL(cxgb4_dbfifo_count);
 
@@ -3368,14 +3376,23 @@ static struct notifier_block cxgb4_netevent_nb = {
 
 static void drain_db_fifo(struct adapter *adap, int usecs)
 {
-        u32 v;
+        u32 v1, v2, lp_count, hp_count;
 
         do {
+                v1 = t4_read_reg(adap, A_SGE_DBFIFO_STATUS);
+                v2 = t4_read_reg(adap, SGE_DBFIFO_STATUS2);
+                if (is_t4(adap->chip)) {
+                        lp_count = G_LP_COUNT(v1);
+                        hp_count = G_HP_COUNT(v1);
+                } else {
+                        lp_count = G_LP_COUNT_T5(v1);
+                        hp_count = G_HP_COUNT_T5(v2);
+                }
+
+                if (lp_count == 0 && hp_count == 0)
+                        break;
                 set_current_state(TASK_UNINTERRUPTIBLE);
                 schedule_timeout(usecs_to_jiffies(usecs));
-                v = t4_read_reg(adap, A_SGE_DBFIFO_STATUS);
-                if (G_LP_COUNT(v) == 0 && G_HP_COUNT(v) == 0)
-                        break;
         } while (1);
 }
 
@@ -3484,24 +3501,62 @@ static void process_db_drop(struct work_struct *work)
 
         adap = container_of(work, struct adapter, db_drop_task);
 
+        if (is_t4(adap->chip)) {
+                disable_dbs(adap);
+                notify_rdma_uld(adap, CXGB4_CONTROL_DB_DROP);
+                drain_db_fifo(adap, 1);
+                recover_all_queues(adap);
+                enable_dbs(adap);
+        } else {
+                u32 dropped_db = t4_read_reg(adap, 0x010ac);
+                u16 qid = (dropped_db >> 15) & 0x1ffff;
+                u16 pidx_inc = dropped_db & 0x1fff;
+                unsigned int s_qpp;
+                unsigned short udb_density;
+                unsigned long qpshift;
+                int page;
+                u32 udb;
+
+                dev_warn(adap->pdev_dev,
+                         "Dropped DB 0x%x qid %d bar2 %d coalesce %d pidx %d\n",
+                         dropped_db, qid,
+                         (dropped_db >> 14) & 1,
+                         (dropped_db >> 13) & 1,
+                         pidx_inc);
+
+                drain_db_fifo(adap, 1);
+
+                s_qpp = QUEUESPERPAGEPF1 * adap->fn;
+                udb_density = 1 << QUEUESPERPAGEPF0_GET(t4_read_reg(adap,
+                                SGE_EGRESS_QUEUES_PER_PAGE_PF) >> s_qpp);
+                qpshift = PAGE_SHIFT - ilog2(udb_density);
+                udb = qid << qpshift;
+                udb &= PAGE_MASK;
+                page = udb / PAGE_SIZE;
+                udb += (qid - (page * udb_density)) * 128;
+
+                writel(PIDX(pidx_inc),  adap->bar2 + udb + 8);
+
+                /* Re-enable BAR2 WC */
+                t4_set_reg_field(adap, 0x10b0, 1<<15, 1<<15);
+        }
+
         t4_set_reg_field(adap, A_SGE_DOORBELL_CONTROL, F_DROPPED_DB, 0);
-        disable_dbs(adap);
-        notify_rdma_uld(adap, CXGB4_CONTROL_DB_DROP);
-        drain_db_fifo(adap, 1);
-        recover_all_queues(adap);
-        enable_dbs(adap);
 }
 
 void t4_db_full(struct adapter *adap)
 {
-        t4_set_reg_field(adap, SGE_INT_ENABLE3,
-                         DBFIFO_HP_INT | DBFIFO_LP_INT, 0);
-        queue_work(workq, &adap->db_full_task);
+        if (is_t4(adap->chip)) {
+                t4_set_reg_field(adap, SGE_INT_ENABLE3,
+                                 DBFIFO_HP_INT | DBFIFO_LP_INT, 0);
+                queue_work(workq, &adap->db_full_task);
+        }
 }
 
 void t4_db_dropped(struct adapter *adap)
 {
-        queue_work(workq, &adap->db_drop_task);
+        if (is_t4(adap->chip))
+                queue_work(workq, &adap->db_drop_task);
 }
 
 static void uld_attach(struct adapter *adap, unsigned int uld)