net/bnxt: fix max rings calculation

Max Tx rings count could be lesser than max Rx rings in some
cases, so take this into account as well.

Account for stat contexts available(one for each ring) along with
no: of completion rings(one for each ring) to cap the max no: of
Tx /Rx rings that can be possibly created.

Fixes: f03e66cb64ce ("net/bnxt: limit queue count for NS3/Stingray devices")
Cc: stable@dpdk.org
Signed-off-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>

diff --git a/drivers/net/bnxt/bnxt.h b/drivers/net/bnxt/bnxt.h
index 3487b91..ddb2681 100644 (file)
--- a/drivers/net/bnxt/bnxt.h
+++ b/drivers/net/bnxt/bnxt.h
@@ -622,12 +622,19 @@ struct bnxt {
        uint16_t                max_tx_rings;
        uint16_t                max_rx_rings;
 #define MAX_STINGRAY_RINGS             128U
-#define BNXT_MAX_RINGS(bp) \
+/* For sake of symmetry, max Tx rings == max Rx rings, one stat ctx for each */
+#define BNXT_MAX_RX_RINGS(bp) \
        (BNXT_STINGRAY(bp) ? RTE_MIN(RTE_MIN(bp->max_rx_rings, \
                                             MAX_STINGRAY_RINGS), \
-                                    bp->max_stat_ctx) : \
-                               RTE_MIN(bp->max_rx_rings, bp->max_stat_ctx))
+                                    bp->max_stat_ctx / 2U) : \
+                               RTE_MIN(bp->max_rx_rings, \
+                                       bp->max_stat_ctx / 2U))
+#define BNXT_MAX_TX_RINGS(bp) \
+       (RTE_MIN((bp)->max_tx_rings, BNXT_MAX_RX_RINGS(bp)))
 
+#define BNXT_MAX_RINGS(bp) \
+       (RTE_MIN((((bp)->max_cp_rings - BNXT_NUM_ASYNC_CPR(bp)) / 2U), \
+                BNXT_MAX_TX_RINGS(bp)))
        uint16_t                max_nq_rings;
        uint16_t                max_l2_ctx;
        uint16_t                max_rx_em_flows;