On 9/14/21 11:21 PM, Aleksander Jan Bajkowski wrote:
Configure the burst length in Ethernet drivers. This improves
Ethernet performance by 58%. According to the vendor BSP,
8W burst length is supported by ar9 and newer SoCs.
The NAT benchmark results on xRX200 (Down/Up):
* 2W: 330 Mb/s
* 4W: 432 Mb/s 372 Mb/s
* 8W: 520 Mb/s 389 Mb/s
Tested on xRX200 and xRX330.
Signed-off-by: Aleksander Jan Bajkowski <olek2@xxxxx>
---
drivers/net/ethernet/lantiq_etop.c | 21 ++++++++++++++++++---
drivers/net/ethernet/lantiq_xrx200.c | 21 ++++++++++++++++++---
2 files changed, 36 insertions(+), 6 deletions(-)
.....
diff --git a/drivers/net/ethernet/lantiq_xrx200.c b/drivers/net/ethernet/lantiq_xrx200.c
index fb78f17d734f..5d96248ce83b 100644
--- a/drivers/net/ethernet/lantiq_xrx200.c
+++ b/drivers/net/ethernet/lantiq_xrx200.c
@@ -71,6 +71,9 @@ struct xrx200_priv {
struct net_device *net_dev;
struct device *dev;
+ int tx_burst_len;
+ int rx_burst_len;
+
__iomem void *pmac_reg;
};
@@ -316,8 +319,8 @@ static netdev_tx_t xrx200_start_xmit(struct sk_buff *skb,
if (unlikely(dma_mapping_error(priv->dev, mapping)))
goto err_drop;
- /* dma needs to start on a 16 byte aligned address */
- byte_offset = mapping % 16;
+ /* dma needs to start on a burst length value aligned address */
+ byte_offset = mapping % (priv->tx_burst_len * 4);
desc->addr = mapping - byte_offset;
/* Make sure the address is written before we give it to HW */
@@ -369,7 +372,7 @@ static int xrx200_dma_init(struct xrx200_priv *priv)
int ret = 0;
int i;
- ltq_dma_init_port(DMA_PORT_ETOP);
+ ltq_dma_init_port(DMA_PORT_ETOP, priv->tx_burst_len, rx_burst_len);
ch_rx->dma.nr = XRX200_DMA_RX;
ch_rx->dma.dev = priv->dev;
@@ -478,6 +481,18 @@ static int xrx200_probe(struct platform_device *pdev)
if (err)
eth_hw_addr_random(net_dev);
+ err = device_property_read_u32(dev, "lantiq,tx-burst-length", &priv->tx_burst_len);
+ if (err < 0) {
+ dev_err(dev, "unable to read tx-burst-length property\n");
+ return err;
+ }
+
+ err = device_property_read_u32(dev, "lantiq,rx-burst-length", &priv->rx_burst_len);
+ if (err < 0) {
+ dev_err(dev, "unable to read rx-burst-length property\n");
+ return err;
+ }
+
I would prefer if you would hard code these values to 8 for the xrx200
driver. All SoCs with this IP block should support this.
/* bring up the dma engine and IP core */
err = xrx200_dma_init(priv);
if (err)
Hauke
