[PATCH v4 8/9] net/enetc: set user configurable priority to TX rings

[Gagandeep Singh <g.singh@nxp.com>]

From: Vanshika Shukla <vanshika.shukla@nxp.com>

Add devarg 'enetc4_txq_prior' to allow per-queue TX ring priority
configuration. The value is a '|'-separated list of TBMR priority
bits, one per TX queue (e.g. 'enetc4_txq_prior=1|2|3').
The configuration accepts values only up to the maximum supported
TX queues. Any additional values beyond this supported range
are discarded.

Store the parsed priorities in hw->txq_prior and apply them in
enetc4_tx_queue_setup() when enabling the ring.

Signed-off-by: Vanshika Shukla <vanshika.shukla@nxp.com>
---
 doc/guides/nics/enetc4.rst             | 12 ++++
 doc/guides/rel_notes/release_26_07.rst |  1 +
 drivers/net/enetc/enetc.h              |  1 +
 drivers/net/enetc/enetc4_ethdev.c      | 81 +++++++++++++++++++++++++-
 4 files changed, 94 insertions(+), 1 deletion(-)

diff --git a/doc/guides/nics/enetc4.rst b/doc/guides/nics/enetc4.rst
index 3c4af22..844b290 100644
--- a/doc/guides/nics/enetc4.rst
+++ b/doc/guides/nics/enetc4.rst
@@ -128,3 +128,15 @@ VF-specific devargs
   Usage example::
 
     dpdk-testpmd -a 0000:00:01.0,enetc4_vsi_delay=10 -- -i
+
+PF/Common devargs
+~~~~~~~~~~~~~~~~~
+
+``enetc4_txq_prior``
+  Set per-queue TX ring priority (TBMR bits).
+  The value is a ``|``-separated list of priority values, one per TX queue.
+  Values beyond the maximum supported TX queue count are discarded.
+
+  Usage example::
+
+    dpdk-testpmd -a 0000:00:00.0,enetc4_txq_prior=1|2|3 -- -i
diff --git a/doc/guides/rel_notes/release_26_07.rst b/doc/guides/rel_notes/release_26_07.rst
index 192623d..495eba0 100644
--- a/doc/guides/rel_notes/release_26_07.rst
+++ b/doc/guides/rel_notes/release_26_07.rst
@@ -195,6 +195,7 @@ New Features
     messaging.
   * Added devargs options ``enetc4_vsi_timeout`` and ``enetc4_vsi_delay``
     for VSI-PSI messaging timeout and delay.
+  * Added devargs option ``enetc4_txq_prior`` to set TX queues priorities.
 
 Removed Items
 -------------
diff --git a/drivers/net/enetc/enetc.h b/drivers/net/enetc/enetc.h
index 80844e9..c12597b 100644
--- a/drivers/net/enetc/enetc.h
+++ b/drivers/net/enetc/enetc.h
@@ -114,6 +114,7 @@ struct enetc_eth_hw {
 	uint32_t max_tx_queues;
 	uint32_t vsi_timeout; /* VSI-PSI message wait timeout (iterations) */
 	uint32_t vsi_delay;   /* VSI-PSI message wait delay (us) */
+	uint32_t *txq_prior;  /* per-queue TX priority (TBMR priority bits) */
 };
 
 /*
diff --git a/drivers/net/enetc/enetc4_ethdev.c b/drivers/net/enetc/enetc4_ethdev.c
index ad1ef4d..7e2d665 100644
--- a/drivers/net/enetc/enetc4_ethdev.c
+++ b/drivers/net/enetc/enetc4_ethdev.c
@@ -3,6 +3,7 @@
  */
 
 #include <stdbool.h>
+#include <rte_kvargs.h>
 #include <rte_random.h>
 #include <dpaax_iova_table.h>
 
@@ -10,6 +11,67 @@
 #include "enetc_logs.h"
 #include "enetc.h"
 
+#define ENETC4_TXQ_PRIORITIES	"enetc4_txq_prior"
+
+static int
+parse_txq_prior(const char *key __rte_unused, const char *value, void *opaque)
+{
+	struct rte_eth_dev *dev = (struct rte_eth_dev *)opaque;
+	struct enetc_eth_hw *hw =
+		ENETC_DEV_PRIVATE_TO_HW(dev->data->dev_private);
+	char *input_str = strdup(value);
+	char *str;
+	uint32_t i = 0;
+
+	if (!input_str)
+		return -ENOMEM;
+
+	hw->txq_prior = calloc(hw->max_tx_queues, sizeof(uint32_t));
+	if (!hw->txq_prior) {
+		free(input_str);
+		return -ENOMEM;
+	}
+
+	str = strtok(input_str, "|");
+	while (str != NULL && i < hw->max_tx_queues) {
+		hw->txq_prior[i++] = (uint32_t)atoi(str);
+		str = strtok(NULL, "|");
+	}
+
+	free(input_str);
+	return 0;
+}
+
+static int
+enetc4_get_devargs(struct rte_eth_dev *dev, const char *key)
+{
+	struct rte_devargs *devargs = dev->device->devargs;
+	struct rte_kvargs *kvlist;
+
+	if (!devargs)
+		return 0;
+
+	kvlist = rte_kvargs_parse(devargs->args, NULL);
+	if (!kvlist)
+		return 0;
+
+	if (!rte_kvargs_count(kvlist, key)) {
+		rte_kvargs_free(kvlist);
+		return 0;
+	}
+
+	if (!strcmp(key, ENETC4_TXQ_PRIORITIES)) {
+		if (rte_kvargs_process(kvlist, key,
+				       parse_txq_prior, (void *)dev) < 0) {
+			rte_kvargs_free(kvlist);
+			return 0;
+		}
+	}
+
+	rte_kvargs_free(kvlist);
+	return 0;
+}
+
 /* Supported Rx offloads */
 static uint64_t dev_rx_offloads_sup =
 	RTE_ETH_RX_OFFLOAD_IPV4_CKSUM |
@@ -316,9 +378,14 @@ enetc4_tx_queue_setup(struct rte_eth_dev *dev,
 	data->tx_queues[queue_idx] = tx_ring;
 	tx_ring->tx_deferred_start = tx_conf->tx_deferred_start;
 	if (!tx_conf->tx_deferred_start) {
+		uint32_t tx_en = ENETC_TBMR_EN;
+
+		/* apply TX queue priority if configured */
+		if (priv->hw.txq_prior)
+			tx_en |= priv->hw.txq_prior[tx_ring->index];
 		/* enable ring */
 		enetc4_txbdr_wr(&priv->hw.hw, tx_ring->index,
-			       ENETC_TBMR, ENETC_TBMR_EN);
+			       ENETC_TBMR, tx_en);
 		dev->data->tx_queue_state[tx_ring->index] =
 			       RTE_ETH_QUEUE_STATE_STARTED;
 	} else {
@@ -1015,6 +1082,8 @@ enetc4_dev_init(struct rte_eth_dev *eth_dev)
 	hw->max_tx_queues = si_cap & ENETC_SICAPR0_BDR_MASK;
 	hw->max_rx_queues = (si_cap >> 16) & ENETC_SICAPR0_BDR_MASK;
 
+	enetc4_get_devargs(eth_dev, ENETC4_TXQ_PRIORITIES);
+
 	ENETC_PMD_DEBUG("Max RX queues = %d Max TX queues = %d",
 			hw->max_rx_queues, hw->max_tx_queues);
 	error = enetc4_mac_init(hw, eth_dev);
@@ -1041,8 +1110,16 @@ enetc4_dev_init(struct rte_eth_dev *eth_dev)
 static int
 enetc4_dev_uninit(struct rte_eth_dev *eth_dev)
 {
+	struct enetc_eth_hw *hw =
+		ENETC_DEV_PRIVATE_TO_HW(eth_dev->data->dev_private);
+
 	PMD_INIT_FUNC_TRACE();
 
+	if (hw->txq_prior) {
+		free(hw->txq_prior);
+		hw->txq_prior = NULL;
+	}
+
 	return enetc4_dev_close(eth_dev);
 }
 
@@ -1071,4 +1148,6 @@ static struct rte_pci_driver rte_enetc4_pmd = {
 RTE_PMD_REGISTER_PCI(net_enetc4, rte_enetc4_pmd);
 RTE_PMD_REGISTER_PCI_TABLE(net_enetc4, pci_id_enetc4_map);
 RTE_PMD_REGISTER_KMOD_DEP(net_enetc4, "* vfio-pci");
+RTE_PMD_REGISTER_PARAM_STRING(net_enetc4,
+			      ENETC4_TXQ_PRIORITIES "=<string>");
 RTE_LOG_REGISTER_DEFAULT(enetc4_logtype_pmd, NOTICE);
-- 
2.25.1