openwrt/target/linux/bcm27xx/patches-4.19/950-0470-bcmgenet-Better-coalescing-parameter-defaults.patch

From bb3075a2edb5c55d0ea7470da8bb44cc9f36aa02 Mon Sep 17 00:00:00 2001
From: Phil Elwell <phil@raspberrypi.org>
Date: Wed, 27 Mar 2019 13:45:46 +0000
Subject: [PATCH] bcmgenet: Better coalescing parameter defaults

Set defaults for TX and RX packet coalescing to be equivalent to:

  # ethtool -C eth0 tx-frames 10
  # ethtool -C eth0 rx-usecs 50

This may be something we want to set via DT parameters in the
future.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
---
 drivers/net/ethernet/broadcom/genet/bcmgenet.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
@@ -2147,7 +2147,7 @@ static void bcmgenet_init_tx_ring(struct
 
 	bcmgenet_tdma_ring_writel(priv, index, 0, TDMA_PROD_INDEX);
 	bcmgenet_tdma_ring_writel(priv, index, 0, TDMA_CONS_INDEX);
-	bcmgenet_tdma_ring_writel(priv, index, 1, DMA_MBUF_DONE_THRESH);
+	bcmgenet_tdma_ring_writel(priv, index, 10, DMA_MBUF_DONE_THRESH);
 	/* Disable rate control for now */
 	bcmgenet_tdma_ring_writel(priv, index, flow_period_val,
 				  TDMA_FLOW_PERIOD);
@@ -3576,9 +3576,12 @@ static int bcmgenet_probe(struct platfor
 	netif_set_real_num_rx_queues(priv->dev, priv->hw_params->rx_queues + 1);
 
 	/* Set default coalescing parameters */
-	for (i = 0; i < priv->hw_params->rx_queues; i++)
+	for (i = 0; i < priv->hw_params->rx_queues; i++) {
 		priv->rx_rings[i].rx_max_coalesced_frames = 1;
+		priv->rx_rings[i].rx_coalesce_usecs = 50;
+	}
 	priv->rx_rings[DESC_INDEX].rx_max_coalesced_frames = 1;
+	priv->rx_rings[DESC_INDEX].rx_coalesce_usecs = 50;
 
 	/* libphy will determine the link state */
 	netif_carrier_off(dev);