[PATCH v3 17/17] net/dpaa2: add devargs alternative for data stashing getenv

[Maxime Leroy]

The DPAA2_DATA_STASHING_OFF environment variable is used by customers
to dynamically disable data stashing without rebuilding their
application. Add a devargs option "drv_no_data_stashing" as an
alternative, consistent with the existing devargs pattern (drv_loopback,
drv_no_prefetch, drv_no_taildrop), while keeping the getenv for
backward compatibility.

Move the check from dpaa2_dev_rx_queue_setup() to dpaa2_dev_init(),
consistent with how other driver flags are handled.

Signed-off-by: Maxime Leroy <maxime at leroys.fr>
---
 drivers/net/dpaa2/dpaa2_ethdev.c | 12 ++++++++++--
 drivers/net/dpaa2/dpaa2_ethdev.h |  3 +++
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/drivers/net/dpaa2/dpaa2_ethdev.c b/drivers/net/dpaa2/dpaa2_ethdev.c
index d9d8ba26a9..31fdef8598 100644
--- a/drivers/net/dpaa2/dpaa2_ethdev.c
+++ b/drivers/net/dpaa2/dpaa2_ethdev.c
@@ -35,6 +35,7 @@
 #define DRIVER_RX_PARSE_ERR_DROP "drv_rx_parse_drop"
 #define DRIVER_ERROR_QUEUE  "drv_err_queue"
 #define DRIVER_NO_TAILDROP  "drv_no_taildrop"
+#define DRIVER_NO_DATA_STASHING "drv_no_data_stashing"
 #define CHECK_INTERVAL         100  /* 100ms */
 #define MAX_REPEAT_TIME        90   /* 9s (90 * 100ms) in total */
 
@@ -929,7 +930,7 @@ dpaa2_dev_rx_queue_setup(struct rte_eth_dev *dev,
 		options |= DPNI_QUEUE_OPT_FLC;
 		cfg.flc.stash_control = true;
 		dpaa2_flc_stashing_clear_all(&cfg.flc.value);
-		if (getenv("DPAA2_DATA_STASHING_OFF")) {
+		if (priv->flags & DPAA2_DATA_STASHING_OFF) {
 			dpaa2_flc_stashing_set(DPAA2_FLC_DATA_STASHING, 0,
 				&cfg.flc.value);
 			dpaa2_q->data_stashing_off = 1;
@@ -2893,6 +2894,12 @@ dpaa2_dev_init(struct rte_eth_dev *eth_dev)
 		DPAA2_PMD_INFO("Rx taildrop disabled");
 	}
 
+	if (dpaa2_get_devargs(dev->devargs, DRIVER_NO_DATA_STASHING) ||
+	    getenv("DPAA2_DATA_STASHING_OFF")) {
+		priv->flags |= DPAA2_DATA_STASHING_OFF;
+		DPAA2_PMD_INFO("Data stashing disabled");
+	}
+
 	/* For secondary processes, the primary has done all the work */
 	if (rte_eal_process_type() != RTE_PROC_PRIMARY) {
 		/* In case of secondary, only burst and ops API need to be
@@ -3391,5 +3398,6 @@ RTE_PMD_REGISTER_PARAM_STRING(NET_DPAA2_PMD_DRIVER_NAME,
 		DRIVER_TX_CONF "=<int>"
 		DRIVER_RX_PARSE_ERR_DROP "=<int>"
 		DRIVER_ERROR_QUEUE "=<int>"
-		DRIVER_NO_TAILDROP "=<int>");
+		DRIVER_NO_TAILDROP "=<int>"
+		DRIVER_NO_DATA_STASHING "=<int>");
 RTE_LOG_REGISTER_DEFAULT(dpaa2_logtype_pmd, NOTICE);
diff --git a/drivers/net/dpaa2/dpaa2_ethdev.h b/drivers/net/dpaa2/dpaa2_ethdev.h
index 86b3022ddb..4da47a543a 100644
--- a/drivers/net/dpaa2/dpaa2_ethdev.h
+++ b/drivers/net/dpaa2/dpaa2_ethdev.h
@@ -97,6 +97,9 @@
  */
 #define DPAA2_TX_DYNAMIC_CONF_ENABLE	RTE_BIT32(9)
 
+/* Disable data stashing (prefetch of packet data into CPU cache) */
+#define DPAA2_DATA_STASHING_OFF		RTE_BIT32(10)
+
 #define DPAAX_RX_ERROR_QUEUE_FLAG	RTE_BIT32(11)
 
 /* DPDMUX index for DPMAC */
-- 
2.43.0