net/sfc/base: more accurately calculate number of PS credits

[dpdk.git] / drivers / net / sfc / base / ef10_ev.c

diff --git a/drivers/net/sfc/base/ef10_ev.c b/drivers/net/sfc/base/ef10_ev.c
index d9389da..2c6edf3 100644 (file)
--- a/drivers/net/sfc/base/ef10_ev.c
+++ b/drivers/net/sfc/base/ef10_ev.c
@@ -774,7 +774,7 @@ ef10_ev_rx_packed_stream(
        __in_opt        void *arg)
 {
        uint32_t label;
-       uint32_t next_read_lbits;
+       uint32_t pkt_count_lbits;
        uint16_t flags;
        boolean_t should_abort;
        efx_evq_rxq_state_t *eersp;
@@ -782,23 +782,28 @@ ef10_ev_rx_packed_stream(
        unsigned int current_id;
        boolean_t new_buffer;
 
-       next_read_lbits = EFX_QWORD_FIELD(*eqp, ESF_DZ_RX_DSC_PTR_LBITS);
+       pkt_count_lbits = EFX_QWORD_FIELD(*eqp, ESF_DZ_RX_DSC_PTR_LBITS);
        label = EFX_QWORD_FIELD(*eqp, ESF_DZ_RX_QLABEL);
        new_buffer = EFX_QWORD_FIELD(*eqp, ESF_DZ_RX_EV_ROTATE);
 
        flags = 0;
 
        eersp = &eep->ee_rxq_state[label];
-       pkt_count = (EFX_MASK32(ESF_DZ_RX_DSC_PTR_LBITS) + 1 +
-           next_read_lbits - eersp->eers_rx_stream_npackets) &
+
+       /*
+        * RX_DSC_PTR_LBITS has least significant bits of the global
+        * (not per-buffer) packet counter. It is guaranteed that
+        * maximum number of completed packets fits in lbits-mask.
+        * So, modulo lbits-mask arithmetic should be used to calculate
+        * packet counter increment.
+        */
+       pkt_count = (pkt_count_lbits - eersp->eers_rx_stream_npackets) &
            EFX_MASK32(ESF_DZ_RX_DSC_PTR_LBITS);
        eersp->eers_rx_stream_npackets += pkt_count;
 
        if (new_buffer) {
                flags |= EFX_PKT_PACKED_STREAM_NEW_BUFFER;
-               if (eersp->eers_rx_packed_stream_credits <
-                   EFX_RX_PACKED_STREAM_MAX_CREDITS)
-                       eersp->eers_rx_packed_stream_credits++;
+               eersp->eers_rx_packed_stream_credits++;
                eersp->eers_rx_read_ptr++;
        }
        current_id = eersp->eers_rx_read_ptr & eersp->eers_rx_mask;
@@ -1336,9 +1341,11 @@ ef10_ev_rxlabel_init(
        __in            efx_evq_t *eep,
        __in            efx_rxq_t *erp,
        __in            unsigned int label,
-       __in            boolean_t packed_stream)
+       __in            efx_rxq_type_t type)
 {
        efx_evq_rxq_state_t *eersp;
+       boolean_t packed_stream = (type >= EFX_RXQ_TYPE_PACKED_STREAM_1M) &&
+           (type <= EFX_RXQ_TYPE_PACKED_STREAM_64K);
 
        EFSYS_ASSERT3U(label, <, EFX_ARRAY_SIZE(eep->ee_rxq_state));
        eersp = &eep->ee_rxq_state[label];
@@ -1363,7 +1370,7 @@ ef10_ev_rxlabel_init(
        eersp->eers_rx_packed_stream = packed_stream;
        if (packed_stream) {
                eersp->eers_rx_packed_stream_credits = (eep->ee_mask + 1) /
-                   (EFX_RX_PACKED_STREAM_MEM_PER_CREDIT /
+                   EFX_DIV_ROUND_UP(EFX_RX_PACKED_STREAM_MEM_PER_CREDIT,
                    EFX_RX_PACKED_STREAM_MIN_PACKET_SPACE);
                EFSYS_ASSERT3U(eersp->eers_rx_packed_stream_credits, !=, 0);
                /*